PHARMAVENE INC
S-1/A, 1996-07-05
PHARMACEUTICAL PREPARATIONS
Previous: UROHEALTH SYSTEMS INC, PRE 14A, 1996-07-05
Next: PHARMAVENE INC, 8-A12G, 1996-07-05



<PAGE>
      AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JULY 5, 1996
                                                       REGISTRATION NO. 33-98706
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
 
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------
                                AMENDMENT NO. 2
                                       TO
                                    FORM S-1
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933
                            ------------------------
                                PHARMAVENE, INC.
             (Exact name of Registrant as specified in its charter)
 
<TABLE>
<S>                        <C>                         <C>
        DELAWARE                      2834                  52-1666548
     (State or other           (Primary standard         (I.R.S. employer
      jurisdiction                 industrial             identification
    of incorporation)         classification code             number)
                                    number)
</TABLE>
 
                              1550 EAST GUDE DRIVE
                           ROCKVILLE, MARYLAND 20850
                                 (301) 838-2500
  (Address, including zip code, and telephone number, including area code, of
                   Registrant's principal executive offices)
                           --------------------------
                               JAMES D. ISBISTER
                      CHAIRMAN AND CHIEF EXECUTIVE OFFICER
                                PHARMAVENE, INC.
                              1550 EAST GUDE DRIVE
                           ROCKVILLE, MARYLAND 20850
                                 (301) 838-2500
 (Name, including zip code, and telephone number, including area code, of agent
                                  for service)
                           --------------------------
                                   COPIES TO:
 
<TABLE>
<S>                                           <C>
          Sheldon E. Misher, Esq.                             Mark Kessel
          Steven A. Fishman, Esq.                           Jonathan Jewett
    Bachner, Tally, Polevoy & Misher LLP                  Shearman & Sterling
             380 Madison Avenue                           599 Lexington Avenue
          New York, New York 10017                      New York, New York 10022
               (212) 687-7000                                 212-848-4000
</TABLE>
 
          APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO PUBLIC:
  AS SOON AS PRACTICABLE AFTER THIS REGISTRATION STATEMENT BECOMES EFFECTIVE.
 
    If  any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to  Rule 415 under the Securities Act  of
1933, please check the following box.  / /
 
    If  this Form  is filed  to register  additional securities  for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list  the  Securities  Act  registration statement  number  of  the  earlier
registration statement for the same offering.  / /
 
    If  this Form  is a post-effective  amendment filed pursuant  to Rule 462(c)
under the Securities Act,  check the following box  and list the Securities  Act
registration  statement number  of the earlier  effective registration statement
for the same offering.  / /
 
    If delivery of the prospectus is expected  to be made pursuant to Rule  434,
please check the following box.  / /
                           --------------------------
 
                        CALCULATION OF REGISTRATION FEE
 
<TABLE>
<CAPTION>
               TITLE OF EACH CLASS OF                       AMOUNT TO            AGGREGATE            AMOUNT OF
             SECURITIES TO BE REGISTERED                BE REGISTERED (1)   OFFERING PRICE (2)    REGISTRATION FEE
<S>                                                    <C>                  <C>                  <C>
Shares of Common Stock, $.01 par value...............       2,530,000           $30,360,000          $10,469(3)
</TABLE>
 
(1) Includes 330,000 shares subject to the Underwriters' over-allotment option.
(2) Estimated solely for purposes of calculating the registration fee.
(3) A registration fee of $9,518 has previously been paid.
                           --------------------------
 
    THE  REGISTRANT HEREBY  AMENDS THIS REGISTRATION  STATEMENT ON  SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A  FURTHER  AMENDMENT  WHICH SPECIFICALLY  STATES  THAT  THIS  REGISTRATION
STATEMENT  SHALL THEREAFTER BECOME EFFECTIVE IN  ACCORDANCE WITH SECTION 8(A) OF
THE SECURITIES ACT  OF 1933  OR UNTIL  THE REGISTRATION  STATEMENT SHALL  BECOME
EFFECTIVE  ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(A),
MAY DETERMINE.
 
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
<PAGE>
                                PHARMAVENE, INC.
 
                             CROSS REFERENCE SHEET
 
                   PURSUANT TO ITEM 501(B) OF REGULATION S-K
 
<TABLE>
<CAPTION>
ITEM AND CAPTION                                                                   LOCATION IN PROSPECTUS
- -----------------------------------------------------------------  ------------------------------------------------------
<S>        <C>                                                     <C>
           Forepart of Registration Statement and Outside Front
           Cover Page of Prospectus..............................
 1.                                                                Outside Front Cover Page
 
           Inside Front and Outside Back Cover Pages of
           Prospectus............................................
 2.                                                                Inside Front and Outside Back Cover Pages
 
           Summary Information, Risk Factors and Ratio of
           Earnings to Fixed Charges.............................
 3.                                                                Prospectus Summary; Risk Factors; Financial Statements
 
           Use of Proceeds.......................................  Prospectus Summary; Use of Proceeds
 4.
 
           Determination of Offering Price.......................
 5.                                                                Outside Front Cover Page; Risk Factors;
                                                                   Underwriting
 
           Dilution..............................................  Risk Factors; Dilution
 6.
 
           Selling Security Holders..............................
 7.                                                                Not Applicable
 
           Plan of Distribution..................................
 8.                                                                Outside Front Cover Page; Underwriting
 
           Description of Securities to be Registered............
 9.                                                                Outside Front Cover Page; Description of Capital Stock
 
           Interests of Named Experts and Counsel................  Legal Matters; Experts
10.
 
           Information With Respect to the Registrant............
11.                                                                Prospectus   Summary;  Risk  Factors;  Capitalization;
                                                                   Selected Financial Data;  Management's Discussion  and
                                                                   Analysis;  Business; Management; Certain Transactions;
                                                                   Principal Stockholders; Financial Statements
 
           Disclosure of Commission Position on Indemnification
           for Securities Act Liabilities........................  Not Applicable
12.
</TABLE>
<PAGE>
INFORMATION   CONTAINED  HEREIN  IS  SUBJECT   TO  COMPLETION  OR  AMENDMENT.  A
REGISTRATION STATEMENT  RELATING TO  THESE SECURITIES  HAS BEEN  FILED WITH  THE
SECURITIES  AND EXCHANGE  COMMISSION. THESE SECURITIES  MAY NOT BE  SOLD NOR MAY
OFFERS TO BUY BE ACCEPTED PRIOR  TO THE TIME THE REGISTRATION STATEMENT  BECOMES
EFFECTIVE.  THIS  PROSPECTUS  SHALL  NOT  CONSTITUTE AN  OFFER  TO  SELL  OR THE
SOLICITATION OF AN OFFER TO BUY NOR SHALL THERE BE ANY SALE OF THESE  SECURITIES
IN  ANY STATE IN WHICH SUCH OFFER,  SOLICITATION OR SALE WOULD BE UNLAWFUL PRIOR
TO REGISTRATION OR QUALIFICATION UNDER THE SECURITIES LAWS OF ANY SUCH STATE.
<PAGE>
PROSPECTUS
                                2,200,000 SHARES
 
                                     [LOGO]
                                PHARMAVENE, INC.
 
                                  COMMON STOCK
                                ----------------
 
    All of the  shares of  Common Stock  offered hereby  are being  sold by  the
Company.  Prior to this offering, there has been no public market for the Common
Stock of  the Company.  It  is currently  anticipated  that the  initial  public
offering  price will be between $10 and  $12 per share. See "Underwriting" for a
discussion of the  factors to be  considered in determining  the initial  public
offering  price. The Common  Stock has been  approved for listing  on the Nasdaq
National Market under the symbol "PHVN," subject to official notice of issuance.
 
    Athena Neurosciences, Inc.,  a wholly-owned subsidiary  of Elan  Corporation
plc, in connection with its license agreement with the Company, has been granted
the right to purchase 220,000 shares of Common Stock in this offering.
                             ---------------------
 
      THE SHARES OF COMMON STOCK OFFERED HEREBY INVOLVE A HIGH DEGREE OF RISK.
                    SEE "RISK FACTORS" BEGINNING ON PAGE 6.
                             ---------------------
THESE  SECURITIES  HAVE  NOT  BEEN APPROVED  OR  DISAPPROVED  BY  THE SECURITIES
   AND   EXCHANGE   COMMISSION   OR    ANY   STATE   SECURITIES    COMMISSION
     NOR   HAS  THE  SECURITIES  AND   EXCHANGE  COMMISSION  OR  ANY  STATE
       SECURITIES   COMMISSION    PASSED    UPON    THE    ACCURACY    OR
           ADEQUACY    OF   THIS   PROSPECTUS.   ANY   REPRESENTATION
                     TO THE CONTRARY IS A CRIMINAL OFFENSE.
 
<TABLE>
<CAPTION>
                                                    Underwriting
                                Price to             Discounts             Proceeds to
                                 Public         and Commissions (1)        Company (2)
<S>                       <C>                   <C>                   <C>
Per Share...............           $                     $                      $
Total (3)...............           $                     $                      $
</TABLE>
 
(1) The Company  has  agreed  to  indemnify  the  Underwriters  against  certain
    liabilities,  including  liabilities under  the Securities  Act of  1933, as
    amended. See "Underwriting."
 
(2) Before deducting estimated expenses of $900,000 payable by the Company.
 
(3) The Company has granted the Underwriters  a 30-day option to purchase up  to
    330,000  additional shares of Common Stock  on the same terms and conditions
    as set forth herein, solely to cover over-allotments, if any. If such option
    is exercised in full, the total Price to Public, Underwriting Discounts  and
    Commissions  and Proceeds  to Company  will be  $            ,  $        and
    $        , respectively. See "Underwriting."
                             ---------------------
 
    The shares of Common Stock offered  by this Prospectus are being offered  by
the  Underwriters,  subject  to  prior  sale,  to  withdrawal,  cancellation  or
modification of the  offer without  notice, to  delivery and  acceptance by  the
Underwriters  and to certain further conditions. It is expected that delivery of
certificates for the  shares of  Common Stock  will be  made at  the offices  of
Lehman Brothers Inc., New York, New York, on or about         , 1996.
                             ---------------------
 
LEHMAN BROTHERS                                           VOLPE, WELTY & COMPANY
 
        , 1996
<PAGE>
    The  following table lists  each of the Company's  12 product candidates and
its intended therapeutic indication, method  of drug delivery and current  stage
of  development. There can  be no assurance  that any of  these products will be
developed successfully or approved by the FDA in a timely manner.
 
<TABLE>
<CAPTION>
   PRODUCT CANDIDATE              INDICATION             DRUG DELIVERY TECHNOLOGY         DEVELOPMENT STAGE
- -----------------------  ----------------------------  ----------------------------  ----------------------------
<S>                      <C>                           <C>                           <C>
Carbatrol                Epilepsy                      Oral sustained-release        505(b)(2) NDA accepted for
                                                                                      filing by the FDA on June
                                                                                      1, 1996/
                                                                                      licensed to Athena
                                                                                      Neurosciences, Inc.
Selegiline SR            Cocaine craving and           Oral sustained-release        Phase III commenced in
                          withdrawal                                                  November 1994
Selegiline SR            Parkinson's Disease           Oral sustained-release        Ready to enter Phase III
BChE Injectable          Cocaine overdose              Injectable                    Preclinical safety and
                                                                                      efficacy studies
                                                                                      substantially completed/
                                                                                      licensed to Rhone-Poulenc
                                                                                      Rorer
BChE Injectable          Post-surgical apnea           Injectable                    Preclinical safety and
                                                                                      efficacy studies
                                                                                      substantially completed/
                                                                                      licensed to Rhone-Poulenc
                                                                                      Rorer
Acyclovir CD             Viral infection               Peptitrol/sustained-release   Formulation development
DHE IR                   Migraine headache             Transmucosal                  Formulation development
                                                        immediate-release/
                                                        Peptitrol
Alprazolam TD            Anxiety                       Transdermal sustained-        Formulation development
                                                        release
Lorazepam TD             Anxiety                       Transdermal sustained-        Formulation development
                                                        release
PI 181.2 TD              Emesis                        Transdermal sustained-        Formulation development
                                                        release
Nifedipine SR            Cardiovascular disease        Oral sustained-release        Formulation development
Insulin CD               Diabetes                      Peptitrol                     Formulation development
</TABLE>
 
    The following are  trademarks of the  Company: Carbatrol-TM-,  Peptitrol-TM-
and Peptiscreen-TM-.
    All  other trademarks appearing in this Prospectus are the property of their
respective holders.
 
                             ---------------------
 
IN CONNECTION  WITH THIS  OFFERING, THE  UNDERWRITERS MAY  OVER-ALLOT OR  EFFECT
TRANSACTIONS  WHICH STABILIZE OR  MAINTAIN THE MARKET PRICE  OF THE COMMON STOCK
OFFERED HEREBY AT A LEVEL ABOVE THAT  WHICH MIGHT OTHERWISE PREVAIL IN THE  OPEN
MARKET.  SUCH STABILIZING, IF  COMMENCED, MAY BE DISCONTINUED  AT ANY TIME. SUCH
TRANSACTIONS MAY  BE  EFFECTED  THROUGH  THE  NASDAQ  NATIONAL  MARKET,  IN  THE
OVER-THE-COUNTER MARKET OR OTHERWISE.
 
                                       2
<PAGE>
                               PROSPECTUS SUMMARY
 
    THE  FOLLOWING SUMMARY  IS QUALIFIED  IN ITS  ENTIRETY BY  THE MORE DETAILED
INFORMATION AND THE FINANCIAL STATEMENTS  AND NOTES THERETO APPEARING  ELSEWHERE
IN  THIS  PROSPECTUS. INVESTORS  SHOULD CAREFULLY  CONSIDER THE  INFORMATION SET
FORTH  UNDER  THE  HEADING  "RISK  FACTORS."  EXCEPT  AS  OTHERWISE  NOTED,  ALL
INFORMATION  IN  THIS  PROSPECTUS  ASSUMES  NO  EXERCISE  OF  THE  UNDERWRITERS'
OVER-ALLOTMENT OPTION  AND REFLECTS  (I) THE  ONE-FOR-SIX REVERSE  SPLIT OF  THE
COMMON  STOCK EFFECTIVE IN MARCH  1996 AND (II) THE  AUTOMATIC CONVERSION OF ALL
OUTSTANDING SHARES  OF MANDATORILY  REDEEMABLE  SERIES A  CONVERTIBLE  PREFERRED
STOCK,  $.01 PAR VALUE (THE "PREFERRED STOCK"),  INTO SHARES OF COMMON STOCK AND
CERTAIN RELATED TRANSACTIONS UPON THE CLOSING OF THIS OFFERING.
 
                                  THE COMPANY
 
    Pharmavene, Inc. (the "Company") develops pharmaceutical products  utilizing
advanced  drug delivery systems.  The Company has developed  a portfolio of drug
delivery and screening technologies  designed to produce  optimal delivery of  a
particular  pharmaceutical product  for a  given indication.  These technologies
include  its   proprietary  Peptitrol   systems  for   the  oral   delivery   of
hard-to-deliver   compounds,   oral  controlled-release   and  sustained-release
delivery,  transmucosal  delivery  through  tissues  in  the  oral  cavity   and
transdermal  delivery. Instead of  emphasizing a specific  drug delivery system,
the Company selects the drug delivery system that it believes is most  effective
for  delivery of a specific  compound and that can  result in such advantages as
convenient dosing,  reduced side  effects,  improved bioavailability  or  easier
administration.  The Company has also  developed various screening technologies,
including its proprietary Peptiscreen system, to systematically and rapidly test
a large number of formulations.
 
    The Company's strategy in selecting its current product candidates has  been
to  generally select pharmaceutical products  for reformulation that the Company
believes have a significant commercial market, that are off-patent or for  which
patent  protection will no longer be available at the time the Company's product
is introduced and  where enhancement of  the method of  delivery is expected  to
have  measurable clinical value as compared to the existing delivery method. The
Company generally selects products for reformulation that treat indications that
have relatively simple,  clear-cut clinical  end-points. Most  of the  Company's
product candidates are reformulations of existing compounds approved by the U.S.
Food  and Drug  Administration (the  "FDA") and  the Company's  delivery systems
usually contain  inactive  ingredients that  are  generally recognized  as  safe
(GRAS)  for food use as  determined by the FDA  or are inactive ingredients that
the Company believes are safe for such use. Therefore, the Company believes that
the development  process for  its products  may  be expedited  and some  of  the
regulatory  approval risks may be reduced. In addition to reformulating existing
compounds, the Company also  intends to seek  arrangements with other  companies
developing  pharmaceutical products based  on new molecular  entities to use the
Company's drug delivery systems to formulate these products.
 
    The  Company's   initial   product   is  expected   to   be   Carbatrol,   a
sustained-release,  patented formulation  of carbamazepine for  the treatment of
epilepsy. In 1994, U.S. sales of carbamazepine were approximately $148  million.
A  major cause of  seizures in epileptic patients  is patient noncompliance with
the treatment regimen,  which can be  caused by frequent  dosing and an  adverse
side  effect profile. Carbatrol would  provide convenient twice-a-day dosing and
could be administered orally as a capsule or sprinkled on food. On June 1, 1996,
the Company's New Drug Application ("NDA") under Section 505(b)(2) (a "505(b)(2)
NDA") of  the Federal  Food, Drug  and  Cosmetic Act,  as amended,  relating  to
Carbatrol  was  accepted  for filing  by  the  FDA. If  approved  for marketing,
Carbatrol, which has been licensed  to Athena Neurosciences, Inc. ("Athena"),  a
wholly-owned  subsidiary of Elan Corporation plc ("Elan"), will compete directly
with CIBA-Geigy's twice-a-day, extended-release formulation of carbamazepine.
 
    The   Company   has   11   other   product   candidates,   including    oral
controlled-release  formulations  of  Selegiline  SR  for  treatment  of cocaine
craving and  for the  treatment of  Parkinson's Disease,  Acyclovir CD  for  the
treatment of viral infections, Nifedipine SR (a generic version of Procardia XL)
for  the treatment of cardiovascular disorders  and Insulin CD for diabetes. The
Company is also developing a transmucosal formulation of dihydroergotamine (DHE)
for  the  treatment   of  migraine  headache,   an  injectable  formulation   of
butyrylcholinesterase  (BChE) for the treatment of  cocaine overdose and for the
treatment of post-
 
                                       3
<PAGE>
surgical  apnea,  as  well  as  three  transdermal  sustained-release  products,
Alprazolam  TD and Lorazepam TD for the treatment of anxiety and PI 181.2 TD for
the treatment of emesis. A number of  these product candidates are in the  early
stages of development.
 
    The   Company  has   developed  its  proprietary   Peptitrol  drug  delivery
technologies for the enhanced oral delivery of pharmaceutical compounds that are
hard to deliver or  have poor oral bioavailability,  such as peptides and  other
large molecules. The Peptitrol drug delivery systems use one or more hydrophobic
or hydrophilic materials to protect the pharmaceutical compound from degradation
and  to increase absorption of the compound from the gastrointestinal tract. The
Company then uses its  proprietary Peptiscreen cell  culture screens to  rapidly
test  the formulations  developed using  Peptitrol technologies.  The Company is
currently in the process of developing Acyclovir CD, Insulin CD and DHE IR using
its Peptitrol and Peptiscreen technologies.
 
    The Company generally intends to develop its products and commence  clinical
testing  in humans and then to  seek collaborators to undertake further testing,
obtain regulatory  approval, manufacture  and market  such products.  In  August
1994,  the Company entered  into its first  license agreement with Rhone-Poulenc
Rorer, Inc. and its Armour Pharmaceutical Company subsidiary, which subsequently
merged  with  Behringwerke  to  form   the  Centeon  joint  venture   (together,
"Rhone-Poulenc  Rorer") to develop,  manufacture and market  its BChE Injectable
products for the  treatment of  cocaine overdose and  reversal of  post-surgical
apnea.  The Company's  BChE Injectable products  have been  designated as Orphan
Drugs by the FDA for each of these indications. As a result, the Company may  be
entitled to marketing exclusivity for these indications for a seven-year period,
subject  to  certain limitations,  if it  is  the first  sponsor to  receive FDA
approval for such indications. See "Business -- Government Regulation."
 
    On July 1,  1996, the Company  entered into an  exclusive license  agreement
with  Athena for  the worldwide marketing,  sale and  distribution of Carbatrol.
Carbatrol will be marketed in the United States by Athena and by its  affiliates
or  sublicensees in the rest of the  world. Under the agreement, Athena (i) will
make a $2.0 million payment within ten  days of the execution of the  agreement,
(ii)  will fund all future development costs associated with Carbatrol which are
approved by a steering committee, (iii) will  make a milestone payment of up  to
$8.0  million upon FDA  approval of the  Company's Carbatrol NDA,  of which $5.0
million is creditable  against future royalty  payments which may  be earned  on
product  sales, and (iv) will make future  royalty payments to the Company based
on net sales of Carbatrol. The milestone payment is conditioned upon the absence
of any finding  of exclusivity  for CIBA-Geigy's Tegretol  XR or  any actual  or
threatened  proceeding seeking such a finding. Athena has been granted the right
to purchase 220,000 shares of Common Stock in this offering.
 
    The Company was incorporated in Delaware on December 22, 1989, as  Substance
Abuse  Sciences,  Inc.  In  February  1990,  the  Company  changed  its  name to
Pharmavene, Inc. The Company's executive offices  are located at 1550 East  Gude
Drive, Rockville, Maryland 20850 and its telephone number is (301) 838-2500.
 
                                  THE OFFERING
 
<TABLE>
<S>                                             <C>
Common Stock offered..........................  2,200,000 shares
Common Stock to be outstanding after the
 offering.....................................  8,672,332 shares (1)
Use of proceeds...............................  To fund research and development activities,
                                                including   the  continued   development  of
                                                Carbatrol,   and   for   general   corporate
                                                purposes. See "Use of Proceeds."
Proposed Nasdaq National Market symbol........  "PHVN"
</TABLE>
 
- ------------------
 
(1)  Includes  an aggregate  of 6,182,818  shares of  Common Stock  that will be
     issued upon  consummation  of  this  offering, or  that  have  been  issued
     subsequent  to  March  31,  1996,  in  connection  with  the  conversion of
     Preferred Stock and certain convertible  notes and the exercise of  options
     under  the Stock Option Plan. See  "Capitalization." Excludes as of July 1,
     1996: (i)  1,827,759 shares  of  Common Stock  reserved for  issuance  upon
     exercise of options granted, to be granted or available for grant under the
     Company's  1991  Stock  Option Plan  (the  "Stock Option  Plan");  and (ii)
     665,084 shares  of Common  Stock  reserved for  issuance upon  exercise  of
     warrants  that are outstanding or that the Company has agreed to issue. See
     "Capitalization," "Management -- Stock Options," "Certain Transactions" and
     "Description of Capital Stock."
 
                                       4
<PAGE>
                             SUMMARY FINANCIAL DATA
 
<TABLE>
<CAPTION>
                                                                                                             FOR THE
                                                                                                             PERIOD
                                                                                   FOR THE THREE MONTHS   FEBRUARY 16,
                                               FOR THE YEARS ENDED DECEMBER 31,                           1990 (DATE OF
                                                                                     ENDED MARCH 31,      INCEPTION) TO
                                               ---------------------------------  ----------------------    MARCH 31,
                                                  1993        1994       1995       1995        1996          1996
                                               -----------  ---------  ---------  ---------  -----------  -------------
                                                                (IN THOUSANDS, EXCEPT PER SHARE DATA)
<S>                                            <C>          <C>        <C>        <C>        <C>          <C>
STATEMENT OF OPERATIONS DATA:
  Revenues:
    Licensing revenue........................  $   --       $   2,000  $  --      $  --      $   --         $   2,000
    Research and development revenue.........      --          --            111         95         19            130
    Research and development grants..........        269          194     --         --          --               513
    Interest income..........................         19           46         35          5         10            201
                                               -----------  ---------  ---------  ---------  -----------  -------------
  Total revenues.............................        288        2,240        146        100         29          2,844
                                               -----------  ---------  ---------  ---------  -----------  -------------
  Expenses:
    Research and development.................      3,932        4,936      4,987      1,230      1,266         20,397
    General and administrative...............      1,413        1,317      1,392        369        478          6,777
    Interest expense.........................        426 (1)       132       446         58      3,572 (1)       5,166
                                               -----------  ---------  ---------  ---------  -----------  -------------
  Total expenses.............................      5,771        6,385      6,825      1,657      5,316         32,340
                                               -----------  ---------  ---------  ---------  -----------  -------------
  Net loss...................................  $  (5,483)   $  (4,145) $  (6,679) $  (1,557) $  (5,287  ) $   (29,496  )
                                               -----------  ---------  ---------  ---------  -----------  -------------
                                               -----------  ---------  ---------  ---------  -----------  -------------
  Net loss per common and common equivalent
   share.....................................  $   (1.59  ) $   (1.20) $   (1.91) $   (0.45) $   (1.51  ) $     (8.76  )
                                               -----------  ---------  ---------  ---------  -----------  -------------
                                               -----------  ---------  ---------  ---------  -----------  -------------
  Weighted average common and common
   equivalent shares outstanding.............      3,455        3,458      3,495      3,466      3,508          3,366
                                               -----------  ---------  ---------  ---------  -----------  -------------
                                               -----------  ---------  ---------  ---------  -----------  -------------
</TABLE>
 
<TABLE>
<CAPTION>
                                                                                      MARCH 31, 1996
                                                                        -------------------------------------------
                                                                                                      PRO FORMA
                                                                         ACTUAL    PRO FORMA (2)  AS ADJUSTED(2)(3)
                                                                        ---------  -------------  -----------------
                                                                                      (IN THOUSANDS)
<S>                                                                     <C>        <C>            <C>
BALANCE SHEET DATA:
  Cash and cash equivalents...........................................  $     586    $   2,590        $  24,288
  Working capital (deficit)...........................................       (225)       1,067           22,766
  Total assets........................................................      3,802        4,901           26,600
  Convertible notes...................................................        938       --               --
  Capital lease obligations, less current portion.....................        784          784              784
  Mandatorily Redeemable Series A Convertible Preferred Stock.........     24,697       --               --
  Deficit accumulated during the development stage....................    (29,496)     (32,694)         (32,694)
  Total stockholders' equity (deficit)................................    (24,293)       2,442           24,142
</TABLE>
 
- ------------------
(1)  Includes non-cash charges of  $292,000 during the  year ended December  31,
     1993,  relating to the issuance of warrants  to purchase Common Stock at an
     exercise price below the  fair market value per  share of the Common  Stock
     and  $3,325,000 during the  period ended March 31,  1996 in connection with
     the  conversion  of  an  aggregate   of  $8,000,000  principal  amount   of
     convertible  notes  (the "Convertible  Notes")  into Preferred  Stock  at a
     conversion price below  the originally  agreed upon  conversion price.  See
     "Management's  Discussion and Analysis," "Certain Transactions" and Notes 5
     and 11 of Notes to Financial Statements.
 
(2)  Gives effect to the following events subsequent to March 31, 1996: (i)  the
     borrowing on April 25, 1996 and June 11, 1996 of an aggregate of $2,000,000
     principal amount under a credit agreement with certain stockholders entered
     into  in 1996 (the "1996 Credit Agreement");  (ii) the conversion of all of
     the shares of Preferred  Stock outstanding into  an aggregate of  5,636,452
     shares  of Common Stock  upon the consummation of  this offering; (iii) the
     conversion of all borrowings under  the 1996 Credit Agreement into  545,455
     shares  of Common Stock  upon consummation of  this offering ($3,000,000 of
     such borrowings were outstanding on July 1, 1996 and the foregoing  assumes
     no  additional borrowings  under the 1996  Credit Agreement  and an initial
     public offering price of $11.00 per  share); and (iv) the issuance on  June
     17,  1996 of 911 shares of Common  Stock upon the exercise of options under
     the  Stock  Option  Plan.  See  "Capitalization,"  "Certain  Transactions,"
     "Description of Capital Stock" and the Notes to the Financial Statements.
 
(3)  Adjusted  to give effect  to the sale  of 2,200,000 shares  of Common Stock
     offered hereby at an  assumed initial public offering  price of $11.00  per
     share. See "Capitalization."
 
                                       5
<PAGE>
                                  RISK FACTORS
 
    AN  INVESTMENT IN THE SHARES BEING OFFERED  HEREBY INVOLVES A HIGH DEGREE OF
RISK.  PROSPECTIVE  INVESTORS  SHOULD  CAREFULLY  CONSIDER  THE  FOLLOWING  RISK
FACTORS,  IN ADDITION TO THE OTHER  INFORMATION CONTAINED IN THIS PROSPECTUS, IN
EVALUATING AN INVESTMENT IN THE SHARES OF COMMON STOCK OFFERED HEREBY.
 
    EARLY STAGE OF PRODUCT DEVELOPMENT; TECHNOLOGICAL UNCERTAINTY.  The  Company
is  in the development  stage and the  development of any  products will require
significant further research, development, testing and regulatory approvals  and
will  be subject  to the  risks of  failure inherent  in the  development of new
products based  on  innovative technologies.  No  assurance can  be  given  that
product development expenditures will result in the generation of revenue by the
Company.  Many of the products  being developed by the  Company are still in the
early stages  of  development. As  the  Company obtains  results  of  particular
preclinical  studies and clinical trials, the  Company may abandon projects that
it might otherwise have believed to be promising, some of which may be described
in this Prospectus.
 
    Additionally, the Company  has only  recently developed  its Peptitrol  drug
delivery  systems for  the oral  delivery of  hard-to-deliver compounds  and the
Peptiscreen cell  screens  to  test  the  extent to  which  such  drugs  may  be
transported from the gastrointestinal tract. The Company is currently developing
reformulations  of three drugs, DHE, acyclovir  and insulin, using the Peptitrol
systems. The Company intends  to focus an increasing  portion of its efforts  on
developing  products  using  these  technologies.  Drugs  developed  using these
delivery systems  have  not yet  been  tested in  humans  and there  can  be  no
assurance that they will prove to be effective in preclinical studies in animals
or in clinical studies in humans.
 
    Additional  risks include the  possibility that the  Company's products will
not be  found  to be  safe  and effective  or  will otherwise  fail  to  receive
necessary  regulatory approvals; that the products,  if safe and effective, will
be difficult to manufacture on a large scale or will be uneconomical to  market;
that  the proprietary rights of third parties will preclude or delay the Company
from  marketing  products;  or  that  third  parties  will  market  superior  or
equivalent  products. Accordingly, there can be  no assurance that the Company's
research and  development  activities will  result  in any  commercially  viable
products.  See "Business -- Products in  Development" and "-- Manufacturing" and
"-- Marketing."
 
    NO PRODUCT REVENUE; ACCUMULATED DEFICIT; CONTINUING LOSSES.  The Company  is
in  the development stage. Through March 31,  1996, it had generated no revenues
from sales of any of its products and had incurred losses in each year since its
inception. As  of March  31, 1996,  the Company  had an  accumulated deficit  of
$29,496,000,  principally from costs incurred in research and development of the
Company's  product  candidates  and   from  general  and  administrative   costs
associated  with the Company's  development programs. As of  March 31, 1996, the
Company had a working capital deficit of $225,000.
 
    Although the Company has received  initial license fees under its  agreement
with  Rhone-Poulenc Rorer during 1994,  and Athena during 1996,  there can be no
assurance that  the Company  will receive  any additional  milestone or  royalty
payments  under  such  agreements or  will  enter into  any  other collaborative
arrangements that will result in revenues.  The Company currently does not  have
any  products ready  to be marketed  or any  rights to receive  royalties on any
products ready to be  marketed, and there  can be no assurance  that it will  be
able  to generate any revenues  from product sales, or  that its operations will
become profitable,  even  if it  is  able  to commercialize  any  products.  The
Company's  most  advanced  product  candidate is  Carbatrol,  and  the Company's
operations will  be  disproportionately dependent  upon  Carbatrol's  successful
development.  The Company expects  to incur significant  additional expenses for
research, development,  testing  and regulatory  compliance  activities,  which,
together  with projected  general and  administrative expenses,  are expected to
result in significant continued operating losses for at least several years.
 
    FUTURE CAPITAL  NEEDS;  UNCERTAINTY  OF ADDITIONAL  FUNDING.    The  Company
believes  that the  net proceeds of  this offering, together  with the Company's
available cash  (including the  $2 million  payment due  from Athena  under  its
license  agreement with the  Company), will be sufficient  to fund the Company's
operations for  at  least  the  next 24  months.  However,  the  Company's  cash
requirements  may vary materially from those now planned depending upon numerous
factors, including  whether  and when  the  Company enters  into  other  license
agreements  for its  product candidates  and the  terms of  any such agreements,
whether the Company
 
                                       6
<PAGE>
receives  license   fees  or   milestone   payments  under   any   collaborative
arrangements,  the  extent  to  which  the  Company  may  have  working  capital
requirements to carry necessary inventory and meet other manufacturing costs  in
connection with the Company's product candidates, which will depend on the terms
of  the license agreement entered into  with respect to such potential products,
the progress of the Company's research and development programs, the results  of
clinical  studies, the timing of regulatory submissions, technological advances,
determinations  as  to  commercial  potential  and  the  status  of  competitive
products.  Expenditures  will  also  be  dependent  upon  the  establishment  of
collaborative arrangements with other  companies, the availability of  financing
and other factors.
 
    The  Company plans to seek collaborative arrangements for the development of
all of its product  candidates at such time  as significant funding is  required
for   clinical  testing.  If  the  Company   is  successful  in  obtaining  such
collaborators,  the  collaborators   may  provide  funding   for  such   product
development.  However, if the  Company decides to conduct  clinical trials or to
seek FDA approval  of any of  its product candidates  in the future,  or if  the
Company  decides to undertake the commercialization of any product candidate, it
would require substantial funds  in addition to the  proceeds of this  offering.
There can be no assurance such collaborative arrangements will be entered into.
 
    Accordingly,  there can  be no assurance  that the Company  will not require
additional  financing  or  that  additional  financing,  if  required,  will  be
available on acceptable terms or at all. The Company may seek additional funding
through public or private financings, including equity financings. If additional
funds  are raised by issuing equity securities, further dilution to stockholders
may result. If adequate funds are not available, the Company may be required  to
delay,  reduce  the  scope of  or  eliminate one  or  more of  its  research and
development programs,  or  to license  the  rights  to certain  of  its  product
candidates  on terms that are less favorable to the Company than might otherwise
have been  available. See  "Use of  Proceeds" and  "Management's Discussion  and
Analysis."
 
    NO ASSURANCE OF FDA APPROVAL; GOVERNMENT REGULATION.  The FDA and comparable
agencies   in  foreign  countries  impose   substantial  requirements  upon  the
introduction of therapeutic pharmaceutical products through lengthy and detailed
laboratory, animal and  human clinical  testing, sampling  activities and  other
procedures   that  are   costly  and   time-consuming.  Satisfaction   of  these
requirements typically  takes several  years or  more and  varies  substantially
based  upon the  type, complexity and  novelty of the  compound. FDA regulations
also govern  the  manufacture  and  marketing  of  pharmaceutical  products.  In
addition,  because  the  Company  handles alprazolam  and  lorazepam,  which are
controlled substances, it must be licensed and its facilities must be  inspected
by  the  U.S.  Drug Enforcement  Administration  (the  "DEA") and  the  State of
Maryland. Failure  to  comply with  applicable  FDA, DEA  and  other  regulatory
requirements  can  result in  sanctions  being imposed  on  the Company  and any
contract manufacturers and distributors of  its products. Typical sanctions  can
include  warning  letters,  fines,  product  recalls  or  seizures, injunctions,
refusals to permit products to  be imported into or  exported out of the  United
States, refusals of the FDA to grant premarket approval of drugs or to allow the
Company  to enter  into government  supply contracts,  withdrawals of previously
approved applications and criminal prosecution.
 
    A company  seeking  FDA approval  of  a drug  for  human use  must  file  an
application  with the FDA  pursuant to the  Federal Food, Drug  and Cosmetic Act
(the "FDC Act"), as  amended in 1984  by the Drug  Price Competition and  Patent
Term  Restoration Act of 1984 (the "DPCPTRA"). The FDC Act, as amended, provides
for several types of  applications, including an NDA,  which may be filed  under
either Section 505(b)(1) or Section 505(b)(2) of the FDC Act, and an Abbreviated
New  Drug Application ("ANDA") under Section 505(j)  of the FDC Act. The type of
application required to be  filed depends upon a  variety of factors,  including
the  nature  of the  drug and  the  extent and  availability of  scientific data
supporting the application. Biologics, such  as the Company's BChE product,  are
licensed  pursuant to Section 351  of the Public Health  Service Act and require
submission and FDA approval of both a product license application ("PLA") and an
establishment license application  ("ELA") for  the particular  product and  the
facility manufacturing the product.
 
    The  procedures  that the  Company and  other drug  sponsors must  follow in
submitting these applications are sometimes uncertain and are subject to change.
The   type   of   application   that   the   FDA   is   willing   or   able   to
 
                                       7
<PAGE>
accept  to review a  new drug product  determines the nature  of the information
that must be prepared and submitted in  support of the application and the  time
required  to obtain  FDA approval.  Although the  statutory requirements  may be
subject to  interpretation,  under  their current  administration  by  the  FDA,
Section  505(b)(2) of the  FDC Act permits drug  sponsors to submit applications
for which the investigations required in Section 505(b)(1)(A) and relied upon by
the applicant for approval of the application  were not conducted by or for  the
applicant  and for which the applicant has  not obtained a right of reference or
use from the person by  or for whom the  investigations were conducted. In  this
connection, a petition was filed with the FDA by Pfizer, Inc. ("Pfizer") in 1993
seeking to prohibit reliance by an applicant under a 505(b)(2) NDA on safety and
other  data previously submitted by Pfizer in  support of its NDA for nifedipine
(Procardia XL). While the  FDA recently denied the  petition, it did not  decide
the  legal merits of  the issues presented. Accordingly,  any future decision by
the FDA to accept these or similar  legal arguments could delay the approval  of
505(b)(2) NDA applications generally. See "Business -- Government Regulation."
 
    An  NDA for Carbatrol for the treatment  of epilepsy was accepted for filing
by the FDA on  June 1, 1996  and the clinical  portion of a  Phase III study  of
Selegiline SR for cocaine craving and withdrawal was completed in December 1995.
Selegiline  SR for the treatment of Parkinson's  Disease is ready to enter Phase
III clinical testing. Five of the Company's product candidates could be ready to
enter Phase  I,  II or  III  clinical trials  during  the next  12  months.  See
"Business -- Products in Development." The Company believes that the development
process  for its products may include reduced regulatory submissions and some of
the regulatory approval risks may be reduced because the Company's drug delivery
systems usually  contain inactive  ingredients that  are GRAS  for food  use  as
determined  by the FDA or are inactive ingredients that the Company believes are
safe for such use. However, there are  a number of other factors related to  the
FDA   approval  process,  including  the   requirement,  for  certain  types  of
applications, that manufacturers establish bioequivalence and bioavailability or
the safety and efficacy of proposed  drug products and certain factors  relating
to  the manufacturing processes involved with  making any drug product, that may
delay or preclude approval of one  or more of the Company's product  candidates.
There  can  be no  assurance that  the  Company will  not encounter  problems in
clinical trials that  will cause  the Company  or the  FDA to  delay or  suspend
clinical  trials.  In  addition, there  can  be  no assurance  that  any  of the
Company's product candidates will obtain FDA approval for any indication.
 
    The effect  of  government regulation  may  be  to delay  marketing  of  new
products  for a considerable period of time  or to impose costly procedures upon
the Company's activities, which  may give a  competitive advantage to  companies
with  greater resources that compete with the Company. There can be no assurance
that FDA or other  regulatory approval for any  product candidates developed  by
the  Company will be  granted on a  timely basis, if  at all. Any  such delay in
obtaining, or  failure to  obtain,  such approvals  would adversely  affect  the
marketing  of  the  Company's potential  products  and its  ability  to generate
revenues  or  royalties.  Any  additional  regulation  or  changes  in  existing
regulations could result in limitations or restrictions on the Company's ability
to utilize one or more of its technologies or could delay regulatory approval of
the Company's potential products and could have a material adverse effect on the
Company. See "Business -- Government Regulation."
 
    POSSIBLE  DELAY  IN  BRINGING TO  MARKET  REFORMULATED DRUG  PRODUCTS.   The
Company could  be  delayed  in  bringing some  of  its  potential  drug  product
candidates   to   market  by   marketing   exclusivity  rights   accorded  other
manufacturers under  the DPCPTRA.  Under  the DPCPTRA,  a  drug sponsor  may  be
entitled  to three years  of marketing exclusivity  in the United  States for an
FDA-approved  drug   product  if   new  clinical   investigations  (other   than
bioavailability  studies),  conducted  or  sponsored by  the  drug  sponsor, are
submitted to the FDA and found to be essential to the FDA's approval. Until  FDA
approval  of an NDA,  FDA filings are not  public and it  is typically not known
what, if any, clinical studies are  submitted by a sponsor. In this  connection,
however,  the Company received information pursuant  to a Freedom of Information
Act ("FOIA") request that CIBA-Geigy obtained approval on March 25, 1996 for  an
NDA  supplement for an  extended-release formulation of  carbamazepine under its
brand name Tegretol.  The FOIA documentation  further discloses that  CIBA-Geigy
requested  that the FDA grant it three years marketing exclusivity commencing on
the date of  approval of the  Tegretol NDA  supplement and that  the FDA  denied
CIBA-Geigy's   request  for  such  exclusivity.   See  "Business  --  Government
Regulation."
 
                                       8
<PAGE>
    DEPENDENCE ON PATENTS AND  PROPRIETARY RIGHTS.   The Company's success  will
depend,  in part, on its  ability to obtain patent  protection for its processes
for formulating drug delivery systems and products both in the United States and
in other  countries,  to preserve  its  trade  secrets and  to  operate  without
infringing  upon the proprietary  rights of others. The  Company intends to file
applications as appropriate for patents covering its technologies, products  and
processes. In 1994, a patent expiring in 2011 was issued to the Company covering
the  process for obtaining BChE from plasma. The Company is aware that there may
be an approach for producing BChE using recombinant methods. As a result,  other
parties  may  be able  to  manufacture BChE  for  any and  all  purposes without
infringing the Company's  patent. In 1994,  a patent expiring  in 2011 was  also
issued,  covering the formulation  of the Company's  Carbatrol product. In 1995,
two patents were issued  based on the Company's  Peptitrol technologies. One  of
the  patents, which expires in 2014, is directed to a pharmaceutical preparation
of a drug  which is  poorly soluble  in water,  and which  is incorporated  into
particles  comprised of hydrophobic  fatty acid ester.  The second patent, which
also expires in  2014, is  directed to a  pharmaceutical preparation  of a  drug
incorporated  into  particles  formed  of alternate  layers  of  hydrophobic and
hydrophilic materials.  The  issued  patents  do  not  cover  the  microemulsion
formulations,  which  are  a  significant  component  of  the  Company's product
development efforts using its  Peptitrol technologies. The  Company is aware  of
other   pharmaceutical  companies  that  are  working  with  microemulsions  and
hydrophobic materials for use in drug  delivery. In 1996, a patent, expiring  in
2015,  was issued for  the Company's formulation of  Selegiline SR. No assurance
can be given that any  additional patents will issue  from any of the  Company's
patent  applications or that,  if patents do  issue, the claims  allowed will be
sufficiently broad to protect the Company's technologies. Although a patent  has
a  statutory presumption  of validity  in the United  States, the  issuance of a
patent is not conclusive as to such  validity or as to the enforceable scope  of
the  claims of the patent.  There can be no  assurance that the Company's issued
patents or any patents  subsequently issued to or  licensed by the Company  will
not  be successfully challenged in the future. The validity or enforceability of
a patent  after  its  issuance  by  the  patent  office  can  be  challenged  in
litigation.  If the  outcome of the  litigation is  adverse to the  owner of the
patent, third parties  may then  be able  to use  the invention  covered by  the
patent,  in  some cases  without payment.  There  can be  no assurance  that the
Company's patents will not be  infringed or successfully avoided through  design
innovation.
 
    There  can be no assurance  that patents or patent  applications owned by or
licensed to the Company will result in patents being issued or that, if  issued,
the  patents will afford protection against competitors with similar technology.
For  example,  other  companies  are  evaluating  microemulsions,   hydrophobic,
transdermal,  transmucosal and  sustained-release oral formulations.  It is also
possible that third parties may obtain  patent or other proprietary rights  that
may  be necessary  or useful to  the Company.  In cases where  third parties are
first to invent a  particular product or technology,  it is possible that  those
parties will obtain patents that will be sufficiently broad so as to prevent the
Company   from  using  certain  technologies   or  from  further  developing  or
commercializing certain products. If licenses  from third parties are  necessary
but  cannot  be obtained,  commercialization of  the  related products  would be
delayed or prevented.  The Company is  aware of patent  applications and  issued
patents  that belong to competitors and it is uncertain whether any of these, or
any other  filed patent  applications of  which the  Company does  not have  any
knowledge,  will  require  the  Company  to  alter  its  potential  products  or
processes, pay licensing fees or cease certain activities.
 
    The Company's principal  product candidates are  reformulations of  existing
products.  Therefore, patents, if any, issued to the Company will only cover the
Company's formulation  of  the product  or  the process  for  manufacturing  the
product.  Others  may  be able  to  develop formulations  which  provide similar
advantages to the  Company's, but which  do not infringe  the Company's  patent.
Additionally,  patents issued or which may be  issued in the future with respect
to Peptitrol or  other drug delivery  systems may not  be sufficiently broad  to
preclude others from developing products that compete with products developed by
the  Company.  For example,  although the  Company's  issued patents  and patent
applications relating  to  Peptitrol  may prevent  competitors  from  developing
products  using formulations covered by the Company's patents, the patents would
not preclude  other companies  from formulating  drugs using  technologies  that
could provide similar results.
 
                                       9
<PAGE>
    The Company's product candidates may conflict with patents that have been or
may  be granted to competitors, universities  or others. In addition, such other
persons could  bring legal  actions  against the  Company claiming  damages  and
seeking  to enjoin manufacturing and marketing  of the affected products. If any
such actions are successful, in addition to any potential liability for damages,
the Company  could be  required to  obtain a  license in  order to  continue  to
manufacture  or market the affected products. There can be no assurance that the
Company would prevail in any such action or that any license required under  any
such  patent would be  made available on acceptable  terms. The Company believes
that there may be  significant litigation in the  industry regarding patent  and
other  intellectual property  rights. If  the Company  becomes involved  in such
litigation, it could consume substantial resources.
 
    The Company is conducting research to identify and develop a formulation  of
nifedipine  that is bioequivalent  to Procardia XL,  marketed by Pfizer, without
infringing Pfizer's existing patents  on Procardia XL. While  the patent on  the
compound  nifedipine has expired, Pfizer has been issued patents with respect to
its once-a-day formulation,  Procardia XL. There  can be no  assurance that  the
Company  will  be  successful  in developing  a  generic  reformulation  that is
bioequivalent to Procardia XL  and that does not  infringe Pfizer's patents.  If
the  Company  successfully  develops  a  nifedipine  reformulation,  the Company
expects that it or its licensee will file  an ANDA with the FDA with respect  to
the  reformulation. Since the filing of an  ANDA or other drug application for a
product covered by  a patent  is an act  of infringement,  the Company  believes
Pfizer  would file a lawsuit against the Company and its licensee, if any, if it
believed that  it had  a claim  that the  Company's formulation  was covered  by
Pfizer's  patents. The filing of a patent  action could delay the approval of an
ANDA for a period of  up to 30 months,  or longer if so  ordered by a court.  If
Pfizer  successfully  asserts  its patents,  the  Company may  be  enjoined from
selling its product until the Pfizer patent expires.
 
    The Company also relies on trade secrets and proprietary know-how, which  it
seeks  to protect,  in part,  by confidentiality  agreements with  its corporate
partners, collaborators, employees  and consultants. There  can be no  assurance
that  these agreements will not be breached, that the Company will have adequate
remedies for any breach or that  the Company's trade secrets will not  otherwise
become known or be independently discovered by competitors.
 
    OTHER  GENERIC  DRUG RISKS;  MARKET ACCEPTANCE.    Certain of  the Company's
product candidates  would  compete with  existing  drugs for  the  treatment  of
epilepsy,   Parkinson's  Disease,  migraine  headache,  anxiety,  cardiovascular
disease, viral infection and diabetes. The Company's strategy generally has been
to develop reformulations for existing compounds for which patent protection  or
market  exclusivity is no longer available or will no longer be available at the
time the  Company's product  is introduced.  To the  extent that  the  Company's
products  consist  of  reformulations  of  available  compounds,  the  Company's
products will be competing with the original brand-name product. Generally, such
brand-name versions of  pharmaceutical compounds  have a  market advantage  over
generic  products  using the  same compound.  Accordingly,  the Company  and any
potential collaborator  may  be required  to  demonstrate to  physicians,  other
heathcare  providers  and administrators  that  the Company's  reformulations of
previously available compounds will in fact offer distinct advantages over  such
products.  In addition, to  the extent that the  manufacturers of the brand-name
products seek  to  develop their  own  generic  or improved  versions  of  these
products  that  provide benefits  similar to  the Company's  reformulations, the
Company may  find  itself  at  a  competitive  disadvantage  by  virtue  of  its
competitors' ability to use the name-brand in the advertising of its products.
 
    DEPENDENCE  UPON OTHERS.   The  Company's strategy  for commercialization of
products  will  generally  require  entering  into  various  arrangements   with
corporate  collaborators. The Company has entered  into a license agreement with
Rhone-Poulenc Rorer with respect to the development, production and marketing of
its two BChE Injectable products and with Athena with respect to the  marketing,
sale  and distribution of  Carbatrol. The Company has  also had discussions with
other parties  concerning  additional  product  development,  manufacturing  and
marketing agreements. Although the Company believes that its collaborators would
have   an  economic  motivation  to  succeed  in  performing  their  contractual
responsibilities, the amount  and timing  of resources  to be  devoted to  these
activities  by them are not  within the control of the  Company. There can be no
assurance that such collaborators will perform their obligations as expected  or
that  the Company  will derive  any additional  revenue from  such arrangements.
There can also be no assurance that
 
                                       10
<PAGE>
the Company's collaborators will not pursue existing or alternative technologies
in preference to products being developed in collaboration with the Company.  In
addition,  there can be  no assurance that the  Company's collaborators will pay
any additional option or license fees to  the Company or that they will  develop
and  market  any products  under the  agreements. Furthermore,  there can  be no
assurance that the Company  will be able  to negotiate additional  collaborative
arrangements  in  the  future on  acceptable  terms,  if at  all,  or  that such
collaborative arrangements will be successful. See "Business -- Strategy."
 
    LIMITED MANUFACTURING  CAPABILITY AND  EXPERIENCE.   The  Company  generally
intends  to  enter  into  collaborative  arrangements  to  complete development,
manufacture and  market its  product candidates.  The Company  expects that  its
collaborators  will  assume responsibility  for manufacturing,  as Rhone-Poulenc
Rorer has done for the Company's BChE  Injectable products and as Athena in  the
future  is  obligated  to do  with  respect  to Carbatrol.  Under  the Company's
agreement with Athena, Athena  has agreed to pay  the Company's costs under  its
current  manufacturing  agreements  and,  upon  expiration  of  such agreements,
directly to  arrange for  manufacture of  Carbatrol. However,  there can  be  no
assurance  that the Company will  be able to enter  into any other collaborative
arrangements  or  will  enter  into   a  collaborative  arrangement  where   the
collaborator  assumes  responsibility for  manufacturing. The  Company currently
does not  have facilities  or  personnel capable  of directly  manufacturing  in
commercial quantities any of the products it may develop.
 
    The  Company has entered into an exclusive agreement with Niro Inc. ("Niro")
for the manufacture of  the pellets to  be used in  Carbatrol. In addition,  the
Company has entered into an agreement in with The P.F. Laboratories, Inc. ("P.F.
Labs")  to encapsulate  and package  Carbatrol. Initially,  the Company  will be
relying solely  on  Niro for  the  manufacture of  the  pellets to  be  used  in
Carbatrol  and on P.F. Labs for encapsulation  and packaging of this product. In
addition, the Company will initially have only a single source of  carbamazepine
and  capsules qualified by the FDA. Although the Company believes that there are
alternative  sources   available  to   manufacture  Carbatrol   and  to   supply
carbamazepine  and the capsules, the substitution of an alternative manufacturer
would require additional FDA  approval and could result  in delays, which  could
materially  adversely affect the Company. In addition, Niro has no experience in
manufacturing pharmaceutical  products and  its facility  will be  subject to  a
pre-approval  inspection by the FDA. See "Business -- Government Regulation." No
assurance can be given that manufacturing or control problems will not arise  or
that the manufacturing process will not be disrupted by circumstances beyond the
Company's control.
 
    It  is  possible  that,  in  the future,  the  Company  may,  if  it becomes
economically attractive to do so, establish its own manufacturing facilities  to
produce  products,  if  any,  that  it may  develop.  In  order  to  establish a
manufacturing facility, the Company will require substantial additional  funding
and  will be  required to hire  and retain significant  additional personnel and
comply  with  the  extensive  current  Good  Manufacturing  Practices   ("cGMP")
regulations imposed by the FDA on such facilities. The Company has no experience
in manufacturing, and no assurance can be given that the Company will be able to
make  the transition successfully to commercial  production, should it choose to
do so. See "Business -- Manufacturing."
 
    NO MARKETING  AND  SALES  CAPABILITY;  DEPENDENCE  UPON  THIRD  PARTIES  FOR
MARKETING.   The Company has no marketing and sales staff and no experience with
respect to marketing pharmaceutical products.  The Company generally intends  to
enter   into   collaborative  arrangements   for  completing   the  development,
manufacturing, distribution  and  marketing  of  its  products.  Therefore,  the
Company  will  be  dependent on  the  efforts  of third  parties  to  market its
products. There can  be no assurance  that the Company's  collaborators will  be
successful  in penetrating the markets for  any products developed. In the event
that the collaborator fails to develop a marketable product or fails to market a
product successfully, the Company's business may be adversely affected.
 
    If  the   Company   markets  products   directly,   significant   additional
expenditures  and management resources would be  required to develop an external
sales force  and implement  a marketing  strategy  for a  product. The  sale  of
certain  products  outside  the United  States  will  also be  dependent  on the
successful  completion  of  arrangements  with  future  partners,  licensees  or
distributors in each territory. There can be no
 
                                       11
<PAGE>
assurance  that the Company will be successful in establishing any collaborative
arrangements or that, if established, such future partners will be successful in
commercializing products. See "Business -- Marketing."
 
    UNCERTAINTY OF SUPPLY  OF BCHE; PRODUCT  SAFETY.  The  Company has  licensed
exclusive, worldwide rights for the development, production and marketing of its
BChE  Injectable products to Rhone-Poulenc Rorer.  Because BChE is purified from
human blood plasma,  the ability  of Rhone-Poulenc  Rorer to  produce BChE  will
depend  upon its  ability to  obtain an adequate  supply of  human blood plasma.
While Rhone-Poulenc  Rorer  obtains and  fractionates  blood for  other  of  its
products, there can be no assurance it will have, or be able to, contract for an
adequate  supply of blood plasma to  meet commercial needs. Additionally, plasma
suppliers obtain their supply from human donors who are limited as to the amount
and frequency of donations. Should the supply of suitable plasma donors decline,
Rhone-Poulenc Rorer's ability to produce and sell the Company's BChE  Injectable
products could be adversely affected. In addition, although the Company believes
that  plasma from human donors is screened for infectious diseases, there can be
no assurance  that  regulatory  agencies,  such as  the  FDA,  will  not  impose
additional restrictions on products derived from human plasma or take regulatory
actions  such  as  recalls  of  finished products  already  on  the  market. See
"Business -- Manufacturing."
 
    COMPETITION.    There  are  many  companies  engaged  in  the  research  and
development  of products using  drug delivery systems that  may compete with the
Company's, most of  which have substantially  greater financial,  technological,
research  and development, marketing  and personnel resources  than the Company.
The Company is aware of several drug delivery companies and large pharmaceutical
companies  that  develop  or  market  sustained-release  oral  dosage   systems,
transdermal  or transmucosal drug  delivery systems or  have active research and
development programs  in controlled-release  methods.  Many companies  also  are
developing  technologies  for the  oral delivery  of  peptides and  other poorly
absorbed molecules. The Company is  aware that CIBA-Geigy has recently  received
FDA  approval to market  an extended-release formulation  of carbamazepine under
its brand name Tegretol, which will compete directly with Carbatrol, if and when
it is approved. In addition, the Company is aware of a number of other companies
developing  generic  formulations  of  sustained-release  nifedipine,   improved
formulations  of selegiline,  transmucosal formulations  of DHE  and transdermal
formulations of certain benzodiazepines, including alprazolam and lorazepam  and
improved  methods  of  delivering anti-emetics.  The  Company is  also  aware of
companies working on antivirals with less frequent dosing requirements and  oral
delivery  systems  for insulin  and other  peptides or  proteins. Many  of these
competitors  have  significantly   greater  experience  than   the  Company   in
undertaking  preclinical testing and human clinical trials of new pharmaceutical
products and obtaining FDA and other regulatory approvals. Accordingly,  certain
of  the Company's competitors may succeed in obtaining FDA approval for products
more rapidly  than the  Company. Furthermore,  if the  Company is  permitted  to
commence commercial sales of products, it will also be competing with respect to
manufacturing  efficiency and marketing with  companies having greater resources
and experience  in  these  areas.  The  Company  currently  has  limited  or  no
experience in these areas.
 
    Some  of the Company's  competitors may succeed  in developing products that
are more effective or less costly than any that may be developed by the  Company
and  may  also prove  to be  more  successful than  the Company's  products. The
Company  will   compete   with   off-patent   drug   manufacturers,   brand-name
pharmaceutical  companies  that  manufacture  or  market  off-patent  drugs, the
original manufacturers of brand-name drugs  that continue to produce such  drugs
after patents expire or introduce generic versions or improved reformulations of
their branded products, and manufacturers of new drugs that may compete with the
Company's  products. In addition,  the Company's products  will compete not only
with products employing advanced drug  delivery systems, but also with  products
in  traditional dosage forms. Because selling prices of off-patent drug products
typically decline  as competition  intensifies,  the maintenance  of  profitable
operations  will be dependent, in part,  on the Company's cost of manufacturing,
its ability to demonstrate the benefits of the Company's product and its ability
to develop and introduce new products in a timely manner. The industry in  which
the  Company  proposes to  compete is  characterized  by extensive  research and
 
                                       12
<PAGE>
development efforts and rapid technological progress. There can be no  assurance
that   developments  by  others  will  not  render  the  Company's  products  or
technologies noncompetitive or obsolete. See "Business -- Competition."
 
    DEPENDENCE UPON  KEY  PERSONNEL.    The Company's  success  depends  on  the
continued  contributions  of its  executive  officers, scientific  and technical
personnel and consultants. During the Company's limited operating history,  many
key responsibilities within the Company have been assigned to a relatively small
number  of individuals. The competition for  qualified personnel is intense, and
the loss  of  services of  certain  key  personnel could  adversely  affect  the
business  of the Company. As the Company's development of products advances, the
Company will require additional expertise in areas such as preclinical  testing,
analytical  testing,  clinical  trial  management,  regulatory  affairs, quality
assurance and control  and, if applicable,  manufacturing. Such activities  will
require the addition of new personnel, including management, and the development
of  additional  expertise by  existing  management personnel.  The  inability to
acquire such services or to develop such expertise could have a material adverse
effect on the Company's operations.
 
    UNCERTAINTY RELATED TO HEALTH  CARE REIMBURSEMENT AND  REFORM MEASURES.   In
recent years, there have been numerous proposals to reform the healthcare system
in  the  United  States,  including currently  pending  legislation  relating to
Medicare and Medicaid. Some of these proposals have included measures that would
limit or eliminate  payments for  certain medical procedures  and treatments  or
subject  the  pricing of  pharmaceuticals  to government  control.  In addition,
significant uncertainty exists as to the reimbursement status of  newly-approved
healthcare  products. The Company's success in  generating revenue from sales of
human therapeutic  products  may  depend,  in  part,  on  the  extent  to  which
reimbursement  for the  costs of  such products  and related  treatments will be
available from  third-party  payors  such as  government  health  administration
authorities, private health insurers and other organizations. Third-party payors
are  increasingly  challenging  the  price  and  cost-effectiveness  of  medical
products, and significant uncertainty exists  as to the reimbursement status  of
newly-approved  health care products. If the Company succeeds in bringing one or
more products to market, there  can be no assurance  that such products will  be
considered  cost-effective or that adequate  third-party insurance coverage will
be available for the Company to  establish and maintain price levels  sufficient
to  realize  an appropriate  return on  its  investment in  product development.
Third-party payors are increasingly attempting  to contain health care costs  by
limiting  both  coverage  and  the level  of  reimbursement  of  new therapeutic
products approved for marketing by  the FDA and by  refusing, in some cases,  to
provide  any coverage of  uses of approved products  for disease indications for
which the  FDA has  not granted  marketing approval.  If adequate  coverage  and
reimbursement  levels are not provided by  government and third-party payors for
uses of  the Company's  therapeutic  products, the  market acceptance  of  these
products would be adversely affected.
 
    RISK  OF  PRODUCT LIABILITY;  AVAILABILITY  OF INSURANCE.    The use  of the
Company's product  candidates  in  clinical  trials and  the  marketing  of  any
pharmaceutical  products may expose the Company to product liability claims. The
Company has  obtained a  level of  liability insurance  coverage that  it  deems
appropriate  for  its current  stage of  development. However,  there can  be no
assurance that  the  Company's  present insurance  coverage  is  adequate.  Such
existing coverage will not be adequate as the Company further develops products,
and  no assurance can  be given that  in the future  adequate insurance coverage
will be available  in sufficient  amounts or  at a  reasonable cost,  or that  a
successful  product liability claim or recall  would not have a material adverse
effect on the business or financial condition of the Company.
 
    HAZARDOUS MATERIALS;  ENVIRONMENTAL MATTERS.    The Company's  research  and
development  processes involve the use  of hazardous, controlled and radioactive
materials. The  Company  is  subject  to  federal,  state  and  local  laws  and
regulations  governing the use,  manufacture, storage, handling  and disposal of
such materials and certain  waste products. Although  the Company believes  that
its  procedures for  handling and  disposing of  such materials  comply with the
standards prescribed  by  such laws  and  regulations, the  risk  of  accidental
contamination or injury from these materials cannot be completely eliminated. In
the  event of such an accident, the Company could be held liable for any damages
that result and any  such liability could exceed  the resources of the  Company.
There   can  be  no  assurance  that  the   Company  will  not  be  required  to
 
                                       13
<PAGE>
incur significant costs to comply with environmental laws and regulations in the
future, or that the business or financial  condition of the Company will not  be
materially  or adversely  affected by  current or  future environmental  laws or
regulations. See "Business -- Government Regulation."
 
    CONTROL BY  EXISTING  STOCKHOLDERS;  ANTI-TAKEOVER  PROVISIONS.    Upon  the
completion  of this  offering, the  principal stockholders  of the  Company will
beneficially own  or control  approximately  77% of  the outstanding  shares  of
Common   Stock,   including   immediately  exercisable   options   and  warrants
(approximately 74% if  the Underwriters' over-allotment  option is exercised  in
full).  As a  result, such persons  will be able  to elect all  of the Company's
directors, determine the outcome of all corporate actions requiring  stockholder
approval  and otherwise control the business  of the Company. Such control could
preclude any unsolicited acquisition of  the Company and consequently  adversely
affect the market price of the Common Stock. In addition, the Company's Board of
Directors  is authorized to issue  from time to time  shares of preferred stock,
without stockholder authorization, in one or more designated series or  classes.
The  issuance of preferred stock could make the possible takeover of the Company
or the removal of  the Company's management  more difficult, discourage  hostile
bids  for control of the Company in which stockholders may receive a premium for
their shares of Common Stock or otherwise dilute the rights of holders of Common
Stock and  depress  the  market  price  of  the  Common  Stock.  See  "Principal
Stockholders" and "Description of Capital Stock."
 
    ABSENCE  OF PRIOR TRADING MARKET; POSSIBLE VOLATILITY OF STOCK PRICE.  Prior
to this offering,  there has been  no public  market for the  Common Stock,  and
there  is no assurance that an active  market will develop or be sustained after
this  offering.  The  initial  public  offering  price  will  be  determined  by
negotiation  between the Company and the Representatives of the Underwriters and
may not be indicative of the market  price at which the Common Stock will  trade
after  completion  of  this  offering.  See  "Underwriting"  for  factors  to be
considered in determining such offering price. The market price of the shares of
Common  Stock,  like  that  of  the  common  stock  of  many  other  early-stage
pharmaceutical  companies, is likely to be  highly volatile. Factors such as the
results of  preclinical  studies and  clinical  trials  by the  Company  or  its
competitors, other evidence of the safety or efficacy of products of the Company
or its competitors, announcements of technological innovations or new commercial
therapeutic products by the Company or its competitors, governmental regulation,
changes  in  reimbursement  policies,  healthcare  legislation,  developments in
patent or other proprietary rights, developments in the Company's  relationships
with  future collaborators, if any, public concern as to the safety and efficacy
of drugs  developed by  the  Company, fluctuations  in the  Company's  operating
results,  and general  market conditions  may have  a significant  impact on the
market price of the Common Stock.
 
    FUTURE SALES OF COMMON STOCK; REGISTRATION  RIGHTS.  Future sales of  shares
of  Common  Stock  by  existing  stockholders pursuant  to  Rule  144  under the
Securities Act of 1933, as amended (the "Securities Act"), through the  exercise
of  outstanding registration rights or through  the issuance of shares of Common
Stock upon exercise  of options, warrants  or otherwise, could  have an  adverse
effect  on the price of the Company's Common Stock. In addition to the 2,200,000
shares of Common Stock offered hereby, approximately 4,756,577 shares of  Common
Stock  will be eligible for sale in the public market subject to compliance with
Rule 144 and Rule 701 under the Securities Act, beginning 90 days from the  date
of  this Prospectus. All  of the Company's executive  officers and directors and
certain stockholders, beneficially  owning an aggregate  of 7,569,968 shares  of
Common  Stock (including 3,752,114  shares eligible for  sale commencing 90 days
after the date of this Prospectus),  however, have agreed with the  Underwriters
not  to sell or otherwise dispose of their  shares for a period of 180 days from
the date of this Prospectus without the prior written consent of Lehman Brothers
Inc. Additionally,  commencing  180 days  after  the date  of  this  Prospectus,
holders  of 7,015,616 shares  of Common Stock, including  shares of Common Stock
issuable upon exercise of warrants, will have registration rights under  certain
conditions.  Additional shares of  Common Stock, including  shares issuable upon
exercise of options  and warrants,  will also become  eligible for  sale in  the
public  market from time to time in the  future. No prediction can be made as to
the effect,  if  any, that  future  sales of  shares  of Common  Stock,  or  the
availability  of such shares for  future sale, will have  on the market price of
the Common Stock prevailing from time  to time. Sales of substantial amounts  of
Common  Stock (including  shares issued upon  exercise of stock  options) in the
public market, or the  perception that such sales  could occur, could  adversely
affect the
 
                                       14
<PAGE>
prevailing  market price of  the Common Stock  or the ability  of the Company to
raise  capital  through  a  public  offering  of  its  equity  securities.   See
"Description  of Capital Stock -- Registration  Rights" and "Shares Eligible for
Future Sale."
 
    DILUTION.  The initial  public offering price  will be substantially  higher
than  the book value per share of  the Common Stock. Investors purchasing shares
of Common Stock in  this offering will incur  immediate net tangible book  value
dilution of $8.22 per share, assuming an initial public offering price of $11.00
per share. See "Dilution."
 
    ABSENCE  OF DIVIDENDS.  The Company has never paid any cash dividends on its
Common Stock and does  not anticipate paying cash  dividends in the  foreseeable
future. See "Dividend Policy."
 
                                USE OF PROCEEDS
 
    The  net proceeds to  the Company from  the sale of  the 2,200,000 shares of
Common Stock offered  hereby, at  an assumed  initial public  offering price  of
$11.00  per share  and after deducting  the underwriting  discount and estimated
expenses payable by the Company,  are estimated to be approximately  $21,700,000
($25,085,000  if the Underwriters' over-allotment  option is exercised in full).
The Company currently anticipates using  substantially all of the net  proceeds,
including  interest  thereon, for  research  and development  and  other product
development activities and  the balance  of the net  proceeds will  be used  for
general corporate purposes.
 
    The amounts and timing of such expenditures may vary significantly depending
upon  numerous  factors,  including whether  and  when the  Company  enters into
license agreements for product candidates and the terms of any such  agreements,
whether  the  Company  receives license  fees  or milestone  payments  under any
collaborative  arrangements,  the  progress   of  the  Company's  research   and
development  programs, the results of clinical studies, the timing of regulatory
submissions, technological advances, determinations  as to commercial  potential
and the status of competitive products. Expenditures will also be dependent upon
the  establishment  of  collaborative  arrangements  with  other  companies, the
availability of  financing and  other  factors. Subject  to the  foregoing,  the
Company  believes  that the  net proceeds  of this  offering, together  with its
available cash  (including the  $2 million  payment due  from Athena  under  its
license  agreement  with  the  Company),  will  be  sufficient  to  finance  its
operations for at least the next 24 months.
 
    Pending such uses, the net proceeds  from this offering will be  temporarily
invested  by  the  Company  in  short-term,  interest  bearing  investment grade
securities.
 
                                DIVIDEND POLICY
 
    The Company has never paid cash dividends on its capital stock and does  not
anticipate  paying  cash  dividends  in  the  foreseeable  future.  The  Company
currently intends to  retain all earnings,  if any, for  the development of  its
business.
 
                                       15
<PAGE>
                                 CAPITALIZATION
 
    The  following  table  sets forth  as  of  March 31,  1996:  (a)  the actual
capitalization of the Company, (b) the  pro forma capitalization of the  Company
after  giving effect to the transactions described in the footnotes to the table
below, and (c) the pro forma capitalization  as adjusted to reflect the sale  by
the  Company of 2,200,000  shares of Common  Stock offered hereby  at an assumed
initial public offering price of $11.00 per share. This table should be read  in
conjunction  with  the  Financial  Statements  and  the  Notes  thereto included
elsewhere in this Prospectus.
 
<TABLE>
<CAPTION>
                                                                                AS OF MARCH 31, 1996
                                                                        ------------------------------------
                                                                                                 PRO FORMA,
                                                                          ACTUAL     PRO FORMA   AS ADJUSTED
                                                                        ----------  -----------  -----------
                                                                                   (IN THOUSANDS)
<S>                                                                     <C>         <C>          <C>
Long-term debt, less current portion
  Convertible Notes...................................................  $      938   $  --        $  --
  Obligations under capital leases....................................         784         784          784
                                                                        ----------  -----------  -----------
      Total long-term debt............................................       1,722         784          784
                                                                        ----------  -----------  -----------
Mandatorily Redeemable Series A Convertible Preferred Stock, $.01 par
 value, 25,363,997 issued and outstanding, actual; no shares
 authorized, issued or outstanding, pro forma and as adjusted.........      24,697      --    (  (2)     --
                                                                        ----------  -----------  -----------
Stockholders' (deficit) equity:
  Preferred Stock -- $.01 par value; 5,000,000 shares authorized, no
   shares issued and outstanding......................................      --          --           --
  Common Stock -- $.01 par value; 25,000,000 shares authorized,
   289,514 shares issued and outstanding, actual; 6,472,332 shares
   issued and outstanding, pro forma; 8,672,332 shares issued and
   outstanding, as adjusted (3)(4)....................................           3          65           87
  Paid-in capital.....................................................       5,200      35,071       56,749
  Deficit accumulated during the development stage....................     (29,496)    (32,694)     (32,694)
                                                                        ----------  -----------  -----------
      Total stockholders' (deficit) equity............................     (24,293)      2,442       24,142
                                                                        ----------  -----------  -----------
          Total capitalization........................................  $    2,126   $   3,226    $  24,926
                                                                        ----------  -----------  -----------
                                                                        ----------  -----------  -----------
</TABLE>
 
- --------------
(1) Upon consummation of this offering, the 25,363,997 shares of Preferred Stock
    then outstanding will be converted into an aggregate of 5,636,452 shares  of
    Common Stock.
 
(2) In  January 1996,  the Company amended  its Certificate  of Incorporation to
    authorize the issuance  of an  additional 5,000,000  shares of  undesignated
    preferred  stock. Upon  conversion of  the outstanding  Preferred Stock upon
    consummation of  this  offering, such  shares  of Preferred  Stock  will  be
    cancelled  and,  accordingly, immediately  thereafter,  the Company  will be
    authorized to issue 5,000,000 shares of preferred stock.
 
(3) 6,182,818 shares of Common Stock were or will be issued subsequent to  March
    31,  1996, as follows: (i) 5,636,452 shares to  be issued at the time of the
    consummation of this offering  upon conversion of  the Preferred Stock  (see
    Note  (2)  above); (ii)  545,455  shares to  be issued  at  the time  of the
    consummation of this offering  upon conversion of  all borrowings under  the
    1996  Credit Agreement into Common Stock ($3,000,000 of such borrowings were
    outstanding on  July  1,  1996  and  the  foregoing  assumes  no  additional
    borrowings  under the 1996  Credit Agreement and  an initial public offering
    price of $11.00 per share); and (iii)  the issuance on June 17, 1996 of  991
    shares of Common Stock upon exercise of options under the Stock Option Plan.
 
(4) Excludes  as of July 1, 1996: (i)  1,827,759 shares of Common Stock reserved
    for issuance upon exercise  of options granted, to  be granted or  available
    for  grant under the Stock Option Plan,  as follows: (a) options to purchase
    an aggregate of  1,202,608 shares  that have  been granted,  (b) options  to
    purchase  53,336 shares that  the Company has committed  to grant to certain
    officers upon consummation of  this offering at an  exercise price equal  to
    the  initial  public offering  price, and  (c)  options to  purchase 571,815
    shares that are available for grant; and (ii) 665,084 shares of Common Stock
    reserved for issuance upon exercise of warrants that are outstanding or that
    the Company has agreed to issue. See "Management -- Stock Options," "Certain
    Transactions" and "Description of Capital Stock."
 
                                       16
<PAGE>
                                    DILUTION
 
    The pro forma  net tangible book  value of  the Company at  March 31,  1996,
after  giving  effect  to transaction  described  in footnote  (1)  to "Selected
Financial Data," would have  been $2,441,727, or $0.38  per share. Net  tangible
book  value per share is  equal to the Company's  total tangible assets less its
total liabilities, divided by the number of shares of Common Stock  outstanding.
After  giving effect to the sale of the 2,200,000 shares of Common Stock offered
hereby at an  assumed initial  public offering price  of $11.00  per share,  and
after  deducting the underwriting discount and estimated expenses payable by the
Company, the pro forma net tangible book value at March 31, 1996 would have been
$24,141,727, or $2.78 per share. This  represents an immediate increase in  such
net  tangible book  value of  $2.40 per  share to  existing stockholders  and an
immediate dilution  in  net  tangible book  value  of  $8.22 per  share  to  new
investors  purchasing shares in  this offering. The  following table illustrates
this per share dilution:
 
<TABLE>
<CAPTION>
Assumed initial public offering price per share...........             $   11.00
<S>                                                         <C>        <C>
  Pro forma net tangible book value per share.............  $    0.38
  Increase per share attributable to new investors........       2.40
                                                            ---------
Pro forma net tangible book value per share after
 offering.................................................                  2.78
                                                                       ---------
Dilution per share to new investors.......................             $    8.22
                                                                       ---------
                                                                       ---------
</TABLE>
 
    The following table summarizes on a pro  forma basis, as of March 31,  1996,
the  difference between the number of shares  of Common Stock purchased from the
Company, the total consideration  paid and the average  price per share paid  by
existing stockholders and by new investors in this offering (assuming an initial
public  offering price of $11.00 per share and before deducting the underwriting
discount and estimated expenses payable by the Company):
 
<TABLE>
<CAPTION>
                                                                            AVERAGE TOTAL
                                                SHARES PURCHASED            CONSIDERATION
                                             -----------------------  --------------------------   PRICE PER
                                               NUMBER      PERCENT       AMOUNT        PERCENT       SHARE
                                             ----------  -----------  -------------  -----------  -----------
<S>                                          <C>         <C>          <C>            <C>          <C>
Existing Stockholders......................   6,472,332       74.6%   $  27,748,168       53.4%    $    4.29
New Investors..............................   2,200,000       25.4       24,200,000       46.6         11.00
                                             ----------      -----    -------------      -----
    Total..................................   8,672,332      100.0%   $  51,948,168      100.0%
                                             ----------      -----    -------------      -----
                                             ----------      -----    -------------      -----
</TABLE>
 
    The foregoing assumes no exercise of the Underwriters' over-allotment option
and assumes no exercise of any outstanding stock options or warrants. At July 1,
1996: (i) there were outstanding options under the Stock Option Plan to purchase
an aggregate of 1,202,608 shares of Common Stock at a weighted average  exercise
price of $4.39 per share; (ii) the Company had agreed to grant options under the
Stock  Option Plan to purchase 53,336 shares of Common Stock to certain officers
upon consummation of this  offering, at an exercise  price equal to the  initial
public  offering price; and (iii) there were outstanding warrants to purchase up
to an aggregate of 665,084 shares of Common Stock at a weighted average exercise
price of $4.17 per  share, assuming an initial  public offering price of  $11.00
per  share. To  the extent  additional shares and  warrants are  issued and such
outstanding options and warrants are  exercised, there will be further  dilution
to  new investors. However,  if all of  the foregoing options  and warrants were
exercised, the amount of dilution per share to new investors would decrease. See
"Management -- Stock Options,"  "Certain Transactions," "Description of  Capital
Stock" and Notes 5 and 6 of Notes to Financial Statements.
 
                                       17
<PAGE>
                            SELECTED FINANCIAL DATA
 
    The  statement of operations data for each  of the three years in the period
ended December 31, 1995 and for the period February 16, 1990 (date of inception)
to December 31, 1995 and balance sheet  data at December 31, 1994 and 1995  have
been  derived from the financial statements of the Company included elsewhere in
this Prospectus that have been audited by Coopers & Lybrand L.L.P.,  independent
accountants, as indicated in their report included elsewhere in this Prospectus.
The  statement of operations data for the years ended December 31, 1991 and 1992
and the balance sheet data at December 31, 1991, 1992 and 1993 have been derived
from the  financial statements  audited  by Coopers  &  Lybrand L.L.P.  but  not
included  in this  Prospectus. The  statement of  operations data  for the three
months ended March 31,  1995 and 1996  and the balance sheet  data at March  31,
1996 are derived from unaudited financial statements included in this Prospectus
and,  in the opinion of management,  include all adjustments (consisting only of
normal recurring  adjustments)  necessary  for  the  fair  presentation  of  the
Company's  financial position and  results of operations  at the end  of and for
such periods. Operating results  for the three months  ended March 31, 1996  are
not  necessarily indicative of results  that may be expected  for the full year.
The following  selected  financial  data  should be  read  in  conjunction  with
"Management's  Discussion and Analysis"  and the Financial  Statements and Notes
related thereto included elsewhere in this Prospectus.
<TABLE>
<CAPTION>
                                                                                                  FOR THE
                                                                                                  PERIOD
                                                                                               FEBRUARY 16,   FOR THE THREE MONTHS
                                                                                               1990 (DATE OF
                                                  FOR THE YEARS ENDED DECEMBER 31,             INCEPTION) TO    ENDED MARCH 31,
                                        -----------------------------------------------------  DECEMBER 31,   --------------------
                                          1991       1992       1993       1994       1995         1995         1995       1996
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
                                                                  (IN THOUSANDS, EXCEPT PER SHARE DATA)
<S>                                     <C>        <C>        <C>        <C>        <C>        <C>            <C>        <C>
STATEMENT OF OPERATIONS DATA:
Revenues:
  Licensing revenue...................  $  --      $  --      $  --      $   2,000  $  --        $   2,000    $  --      $  --
  Research and development revenue....     --         --         --         --            111          111           95         19
  Research and development grants.....         50     --            269        194     --              513       --         --
  Interest income.....................         59         27         19         46         35          191            5         10
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
    Total revenues....................        109         27        288      2,240        146        2,815          100         29
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
Expenses:
  Research and development............      1,570      3,385      3,932      4,936      4,987       19,131        1,230      1,266
  General and administrative..........        675      1,164      1,413      1,317      1,392        6,299          369        478
  Interest expense....................          5      581(1)     426(1)       132        446        1,594           58    3,572(1)
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
    Total expenses....................      2,250      5,130      5,771      6,385      6,825       27,024        1,657      5,316
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
Net loss..............................  $  (2,141) $  (5,103) $  (5,483) $  (4,145) $  (6,679)   $ (24,209)   $  (1,557) $  (5,287)
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
Net loss per common and common
 equivalent share.....................  $   (0.66) $   (1.54) $   (1.59) $   (1.20) $   (1.91)   $   (7.19)   $   (0.45) $   (1.51)
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
Weighted average common and common
 equivalent shares outstanding........      3,243      3,307      3,455      3,458      3,495        3,366        3,466      3,508
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
                                        ---------  ---------  ---------  ---------  ---------  -------------  ---------  ---------
 
<CAPTION>
                                           FOR THE
                                           PERIOD
                                        FEBRUARY 16,
                                        1990 (DATE OF
                                        INCEPTION) TO
                                          MARCH 31,
                                            1996
                                        -------------
 
<S>                                     <C>
STATEMENT OF OPERATIONS DATA:
Revenues:
  Licensing revenue...................    $   2,000
  Research and development revenue....          130
  Research and development grants.....          513
  Interest income.....................          201
                                        -------------
    Total revenues....................        2,844
                                        -------------
Expenses:
  Research and development............       20,397
  General and administrative..........        6,777
  Interest expense....................        5,166
                                        -------------
    Total expenses....................       32,340
                                        -------------
Net loss..............................    $ (29,496)
                                        -------------
                                        -------------
Net loss per common and common
 equivalent share.....................    $   (8.76)
                                        -------------
                                        -------------
Weighted average common and common
 equivalent shares outstanding........        3,366
                                        -------------
                                        -------------
</TABLE>
 
                                                   (FOOTNOTES ON FOLLOWING PAGE)
 
                                       18
<PAGE>
<TABLE>
<CAPTION>
                                                                                                  MARCH 31, 1996
                                                          DECEMBER 31,                       ------------------------
                                      -----------------------------------------------------
                                        1991       1992       1993       1994       1995      ACTUAL    PRO FORMA (2)
                                      ---------  ---------  ---------  ---------  ---------  ---------  -------------
                                                                      (IN THOUSANDS)
<S>                                   <C>        <C>        <C>        <C>        <C>        <C>        <C>
BALANCE SHEET DATA:
Cash and cash equivalents...........  $   1,163  $     529  $   1,187  $   1,045  $     408  $     586    $   2,590
Working capital (deficit)...........        550     (2,096)       348     (2,470)      (955)      (225)       1,067
Total assets........................      1,626      1,189      2,016      1,737      2,613      3,802        4,901
Series A Convertible Preferred
 Stock..............................      3,700      5,697     13,372     14,697     16,697     24,697       --
Capital lease obligations, less
 current portion....................         80        196        218        167        748        784          784
Deficit accumulated during the
 development stage..................     (2,800)    (7,902)   (13,385)   (17,530)   (24,209)   (29,496)     (32,694)
Paid-in capital.....................          6        515        808        811        838      5,200       35,071
Total stockholders' (deficit)
 equity.............................     (2,793)    (7,384)   (12,574)   (16,716)   (23,368)   (24,293)       2,442
 
<CAPTION>
 
                                          PRO FORMA
                                      AS ADJUSTED(2)(3)
                                      -----------------
 
<S>                                   <C>
BALANCE SHEET DATA:
Cash and cash equivalents...........     $    24,288
Working capital (deficit)...........          22,766
Total assets........................          26,600
Series A Convertible Preferred
 Stock..............................         --
Capital lease obligations, less
 current portion....................             784
Deficit accumulated during the
 development stage..................         (32,694)
Paid-in capital.....................          56,749
Total stockholders' (deficit)
 equity.............................          24,142
</TABLE>
 
- --------------
(1) Includes non-cash charges of $501,000  and $292,000 during the fiscal  years
    ended  December 31, 1992 and 1993, respectively, relating to the issuance of
    warrants to purchase Common Stock at an exercise price below the fair market
    value per share  of the  Common Stock and  of $3,325,000  during the  period
    ended  March 31, 1996 in  connection with the conversion  of an aggregate of
    $8,000,000 principal amount of Convertible  Notes into Preferred Stock at  a
    conversion  price  below the  originally agreed  upon conversion  price. See
    "Management's Discussion and Analysis,"  "Certain Transactions" and Notes  5
    and 11 of Notes to Financial Statements.
 
(2) Gives  effect  to following  events subsequent  to March  31, 1996:  (i) the
    borrowing on  April 25  and June  11,  1996 of  an aggregate  of  $2,000,000
    principal amount under the 1996 Credit Agreement; (ii) the conversion of all
    of  the shares of Preferred Stock outstanding into an aggregate of 5,636,452
    shares of Common  Stock upon the  consummation of this  offering; (iii)  the
    conversion  of all borrowings  under the 1996  Credit Agreement into 545,455
    shares of Common  Stock upon  consummation of this  offering ($3,000,000  of
    such  borrowings were outstanding on July  1, 1996 and the foregoing assumes
    no additional  borrowings under  the 1996  Credit Agreement  and an  initial
    public  offering price of $11.00  per share); and (iv)  the issuance on June
    17, 1996 of 911 shares  of Common Stock upon  the exercise of options  under
    the   Stock  Option  Plan.  See  "Capitalization,"  "Certain  Transactions,"
    "Description of Capital Stock" and the Notes to the Financial Statements.
 
(3) Adjusted to give  effect to  the sale of  2,200,000 shares  of Common  Stock
    offered  hereby at  an assumed initial  public offering price  of $11.00 per
    share. See "Capitalization."
 
                                       19
<PAGE>
                      MANAGEMENT'S DISCUSSION AND ANALYSIS
 
OVERVIEW
 
    The Company commenced  operations in February  1990. The Company  is in  the
development  stage and  has devoted  substantially all  of its  resources to the
research  and   development  of   its  product   candidates  and   general   and
administrative  expenses.  Since inception,  the Company  has not  generated any
revenue from  product sales,  but has  received an  aggregate of  $2,643,000  in
licensing  and research and development revenues and grants, its sole sources of
revenue. There  can be  no assurance  that  the Company  will receive  any  such
revenue in the future.
 
    The  Company has  not been profitable  since inception and  expects to incur
substantial operating losses  for at least  the next few  years. For the  period
from  inception to March 31, 1996, the Company incurred a cumulative net loss of
$29,496,000 and,  as  of  March 31,  1996,  had  a working  capital  deficit  of
$225,000.  The  Company expects  its expenses  to  increase substantially  as it
expands its product development activities. The Company's results of  operations
may  vary  significantly  from  quarter  to quarter  due  to  timing  of license
payments, if any,  as well  as the pace  of research  and development  expenses.
Accordingly,  quarterly operating results  may not necessarily  be indicative of
results that may be expected for the full year.
 
RESULTS OF OPERATIONS
 
    THREE MONTHS ENDED MARCH 31, 1996 AND 1995
 
    Total revenues  were  $29,000 in  the  three  months ended  March  31,  1996
compared  to  $100,000 in  the  same period  in  1995. Research  and development
revenue was $19,000 in the three months ended March 31, 1996 compared to $95,000
in the same period in 1995 as a result of payments under the Company's licensing
agreement with Rhone-Poulenc Rorer for the  BChE technology in the three  months
ended  March 31, 1995. The Company does not expect that research and development
revenue will be significant in the  future unless additional licensing or  other
collaborative  agreements are completed. Interest income increased to $10,000 in
the three months ended  March 31, 1996  from $5,000 for the  same period in  the
prior  year  due  primarily  to  higher  average  cash  balances  available  for
short-term investment.
 
    Research and development expenses primarily consist of compensation expenses
for research and development personnel, contract research and development costs,
costs of  clinical  trials, clinical  and  laboratory supplies  and  facilities.
Research and development expenses increased 3% to $1,266,000 in the three months
ended  March 31, 1996 from $1,230,000 in  the three months ended March 31, 1995.
The increase  was  attributable to  higher  compensation expenses  and  facility
costs, partially offset by lower costs of clinical trials and clinical supplies.
Research  and development expenses accounted for  73% and 77% of total operating
expenses for the three months ended March 31, 1996 and 1995 respectively.
 
    General  and  administrative  expenses  primarily  consist  of  compensation
expenses  for  management and  administrative  personnel, professional  fees and
other expenses. General and administrative expenses increased 30% to $478,000 in
the three months ended March  31, 1996 from $369,000 in  the same period in  the
prior  year due primarily  to higher compensation costs  and recruiting costs of
management and administrative personnel.
 
    Interest expense increased to $3,572,000 in the three months ended March 31,
1996 from $58,000 for  the same period  in the prior  year. Interest expense  in
1996  included  a  non-cash  charge  of  $3,394,000  related  primarily  to  the
conversion of Convertible Notes into Preferred Stock at a conversion price below
the  originally  negotiated  conversion   price.  See  "Liquidity  and   Capital
Resources"  and Note 11 of Notes to Financial Statements. Excluding the non-cash
charge, interest expense increased to $178,000  in the three months ended  March
31,  1996 from  $58,000 in  the same  period of  the prior  year as  a result of
increased borrowings under credit agreements and capitalized leases.
 
    FISCAL YEARS ENDED DECEMBER 31, 1995, 1994 AND 1993
 
    Total revenues were  $146,000 in 1995,  $2,240,000 in 1994  and $288,000  in
1993.  Research and development revenue was  $111,000 in the year ended December
31,  1995  resulting   from  payments   under  the   licensing  agreement   with
Rhone-Poulenc  Rorer  relating to  the BChE  technology  transfer. In  1994, the
 
                                       20
<PAGE>
Company received licensing  revenue of $2,000,000,  attributable to the  initial
payment under the Company's licensing agreement with Rhone-Poulenc Rorer for its
BChE technology and $194,000 in research and development revenue from a Phase II
Small Business Innovation Research ("SBIR") grant from the National Institute on
Drug  Abuse  ("NIDA") for  the study  of cocaine  detoxification. The  study was
completed in 1994. The Company was awarded the grant in 1993 in the total amount
of $500,000, under which $194,000 was recognized as revenue in 1994 and $220,000
was recognized as revenue in 1993. The remaining balance of $86,000 has expired.
In addition, the  Company was  awarded a  $49,000 Phase  I SBIR  grant from  the
National  Institute of General Medical Sciences ("NIGMS") to study post-surgical
apnea. The  study was  completed in  1993,  and the  $49,000 was  recognized  as
revenue  in  1993. Interest  income was  $34,000  in 1995,  $46,000 in  1994 and
$19,000  in  1993.  Interest  income  resulted  primarily  from  the   temporary
investment of proceeds from the Company's private placements of Preferred Stock.
 
    Research  and development  expenses increased 1%  to $4,987,000  in the year
ended December 31,  1995 from $4,936,000  in the year  ended December 31,  1994.
Research and development expenses increased 26% in 1994 from $3,932,000 in 1993.
In  1995,  higher  compensation  expenses and  recruiting  costs  for additional
research and development  personnel, consulting expenses  relating to review  of
clinical  and  regulatory progress  on the  Carbatrol  505(b)(2) NDA  and higher
facilities costs due to the Company's relocation, were offset by lower costs  of
clinical  trials, clinical and  laboratory supplies and  lower contract research
and development costs.  The increase  in 1994 from  1993 were  primarily due  to
higher  compensation expenses and  recruiting costs for  additional research and
development personnel,  costs of  clinical  and laboratory  supplies,  equipment
costs  and the costs  of clinical trials.  The number of  full-time employees in
research and development was 44  at December 31, 1995,  35 at December 31,  1994
and  30 at  December 31, 1993.  Research and development  expenses accounted for
78%, 79% and 74% of  total operating expenses of the  Company in 1995, 1994  and
1993, respectively.
 
    General  and administrative expenses increased 6%  to $1,392,000 in the year
ended December 31,  1995 from $1,317,000  in the year  ended December 31,  1994,
primarily as a result of increased professional fees. General and administrative
expenses  in 1994 decreased 7%  from $1,413,000 in 1993,  primarily due to lower
recruiting and relocation expenses  for management and administrative  personnel
and  lower  professional fees,  which were  partially offset  by an  increase in
compensation expenses.
 
    Interest expense increased 238% to $446,000  in 1995 from $132,000 in  1994.
Interest  expense decreased 69% in 1994  from $426,000 in 1993. Interest expense
in 1993 included $292,000  of non-cash charges relating  to interest expense  on
warrants  issued at an exercise price below fair market value in connection with
the Company's  credit  agreements. See  "--  Liquidity and  Capital  Resources,"
"Certain  Transactions" and Note  4 of Notes  to Financial Statements. Excluding
the non-cash  charges,  increased  interest  expense  resulted  from  additional
financings under credit agreements and capitalized leases.
 
LIQUIDITY AND CAPITAL RESOURCES
 
    Since  its  inception  in  1990, the  Company  has  financed  its operations
primarily from (i) private sales of its Preferred Stock, (ii) loans from certain
of its stockholders, (iii) licensing  and research and development revenues  and
grants and (iv) to a lesser extent, capital leases.
 
    Through  March 31,  1996, the Company  had received  proceeds of $24,697,000
from the sale of its Preferred Stock, primarily to HealthCare Ventures II, L.P.,
HealthCare Ventures III, L.P.,  HealthCare Ventures IV,  L.P. and certain  other
institutional investors. Upon consummation of this offering, the Preferred Stock
will be converted into Common Stock.
 
    Since  1991,  the  Company  has  also obtained  loans  from  certain  of its
stockholders. In  1994,  the Company  entered  into the  1994  Credit  Agreement
permitting  it to borrow,  under certain circumstances, up  to $4,395,000 at the
rate of 7 1/4% per annum. The Company borrowed $2,000,000 under the 1994  Credit
Agreement.  These loans were converted into Preferred Stock and the facility was
terminated in May 1995.
 
    In May 1995, the Company entered into the 1995 Credit Agreement with certain
of its stockholders permitting it to borrow  up to $8,000,000 at the rate of  9%
per annum. The Company issued $8,000,000 of
 
                                       21
<PAGE>
Convertible  Notes under the 1995 Credit  Agreement through January 1996. All of
the Convertible Notes were converted into 8,000,000 shares of Preferred Stock in
March 1996. In  connection with  the conversion  of the  Convertible Notes  into
Preferred  Stock at a conversion  price of $1.00 per  share, which was $0.25 per
share less than the originally negotiated conversion price, the Company recorded
a non-cash expense of $3,325,000 in the first quarter of 1996.
 
    Also in March  1996, the  Company entered  into the  1996 Credit  Agreement,
permitting  it to borrow up to $7,300,000 at  the rate of 8 1/2% per annum prior
to the  consummation of  this offering.  As of  July 1,  1996, the  Company  had
borrowed  $3,000,000 under the  1996 Credit Agreement.  All borrowings under the
1996 Credit Agreement will convert into Common Stock at one-half of the  initial
public  offering price  upon consummation of  this offering and  the 1996 Credit
Agreement will  be  terminated.  The  Company expects  to  record  a  $2,100,000
non-cash  expense upon  closing of  this offering  to reflect  this discount. In
connection with the  issuance of  880,000 warrants to  purchase Preferred  Stock
under  the 1996 Credit Agreement, the Company expects to record, upon closing of
this offering,  a  non-cash  expense  of $1,098,000  to  reflect  ascribed  debt
issuance costs. See Note 12 of Notes to Financial Statements.
 
    From its inception through March 31, 1996, the Company received an aggregate
of  $2,643,000 in licensing and research and development revenues and grants. Of
this amount,  $2,000,000 represented  an upfront  fee from  Rhone-Poulenc  Rorer
under the BChE license agreement and most of the balance represented grants from
NIDA, an organization that is part of the National Institutes of Health, to fund
the  Company's research of a treatment  for cocaine addiction. Over this period,
the Company also entered into capital  leases of certain equipment, which had  a
balance of $1,167,000 at March 31, 1996.
 
    On  July 1, 1996, the Company  entered into an exclusive licensing agreement
with Athena for  the worldwide  marketing, sale and  distribution of  Carbatrol.
Under the agreement, Athena (i) will make a $2.0 million payment within ten days
of  execution  of the  agreement, (ii)  will fund  all future  development costs
associated with Carbatrol which are approved by a steering committee, (iii) will
make a milestone payment, upon satisfaction of certain conditions, of up to $8.0
million, of which  $5.0 million  is creditable against  future royalty  payments
which may be earned on product sales, and (iv) will make future royalty payments
to  the Company  based on  net sales  of Carbatrol.  See "Business  -- Licensing
Agreements."
 
    The cash generated by the Company was used to fund its operating activities,
which  used  $24,778,000  through  March  31,  1996,  as  well  as  its  capital
expenditures  for  the  purchase  of  equipment  and  leasehold  improvements of
$866,000 and principal payments on its capital leases of $817,000. At March  31,
1996, the Company had $586,000 of cash and cash equivalents and negative working
capital of $225,000. The increase at December 31, 1995 from December 31, 1994 in
prepaid  assets of $117,000 and in fixed assets of $999,000 related primarily to
deposits, equipment  and  leasehold  improvements  for  the  renovation  of  the
subleased  facility the  Company occupied  in 1995  in Rockville,  Maryland. The
increase in other assets of $416,000 related primarily to the deferred costs  of
this offering.
 
    At  December 31, 1995, the Company  had net operating loss carryforwards for
federal income tax purposes of approximately $18,002,000, which may be available
to reduce future federal income taxes. The utilization of the loss carryforwards
to reduce future income taxes will  depend on the Company's ability to  generate
sufficient  taxable income  prior to  the expiration  of the  net operating loss
carryforwards. The carryforwards begin to expire in the year 2005. However,  the
Tax  Reform Act of 1986 limits the maximum  annual use of net operating loss and
tax credit carryforwards in certain situations where changes occur in the  stock
ownership  of a corporation. As a result of a private sale of Preferred Stock in
June 1993, a change of ownership  was deemed to occur restricting the  Company's
use  of its net operating loss carryforwards. As a result, the Company estimates
that  its  use  of  approximately   $7,500,000  of  these  net  operating   loss
carryforwards (those incurred before June 1993) will be subject to an annual use
limitation. See Note 8 of Notes to Financial Statements.
 
    Following  this offering,  the Company  will require  funds to  continue its
research and development and other  product development activities, to fund  its
other  operating activities  and to fund  its capital expenditures.  In 1996 and
1997, the Company plans to  substantially increase its research and  development
and other product development activities.
 
                                       22
<PAGE>
    Following  this offering, the Company will not have any credit facilities in
place and will not be entitled to a significant amount of licensing payments  or
research  and  development payments  or  grants, unless  certain  milestones are
achieved under its BChE license agreement, its Carbatrol license agreement or it
enters into a license agreement relating  to another of its product  candidates.
The Company's future capital requirements will depend on many factors, including
the  progress of the Company's research and development programs, its success in
entering into  new collaborative  arrangements  and the  amount of  payments  it
receives  thereunder, the results and costs  of preclinical and clinical testing
for the Company's product candidates, the  costs associated with and the  timing
of  regulatory approvals and product  introductions, technological advances, the
status of  competitive products  and  the commercial  success of  the  Company's
products.  There can be no assurance that additional funds, if required, will be
available to the Company on favorable terms, if at all, to permit the Company to
continue with its  plan for operations.  Subject to the  foregoing, the  Company
believes  that the  net proceeds of  this offering, together  with its available
cash (including  the  $2 million  payment  due  from Athena  under  its  license
agreement  with the Company) will be sufficient to finance its operations for at
least the next 24 months. See "Risk Factors -- Future Capital Needs; Uncertainty
of Additional Funding" and "Use of Proceeds."
 
                                       23
<PAGE>
                                    BUSINESS
 
GENERAL
 
    The  Company  develops  pharmaceutical  products  utilizing  advanced   drug
delivery  systems. The  Company has developed  a portfolio of  drug delivery and
screening technologies  designed to  produce optimal  delivery of  a  particular
pharmaceutical  product for a  given indication. These  technologies include its
proprietary  Peptitrol  systems  for   the  oral  delivery  of   hard-to-deliver
compounds,  oral controlled-release and sustained-release delivery, transmucosal
delivery through tissues in the oral cavity and transdermal delivery. Instead of
emphasizing a  specific  drug delivery  system,  the Company  selects  the  drug
delivery  system that it believes  is most effective for  delivery of a specific
compound and that can  result in such advantages  as convenient dosing,  reduced
side effects, improved bioavailability or easier administration. The Company has
also   developed  various  screening  technologies,  including  its  proprietary
Peptiscreen system,  to  systematically  and  rapidly test  a  large  number  of
formulations.
 
    The  Company's strategy in selecting its current product candidates has been
to select a pharmaceutical  product for reformulation based  on its analysis  of
the  potential market and  the likely time  and expense required  to develop the
reformulated pharmaceutical  product.  Accordingly,  the  Company  has  selected
pharmaceutical  products that the Company believes have a significant commercial
market, that are  off-patent or for  which patent protection  will no longer  be
available  at the time the Company's product is introduced and where enhancement
of the  method of  delivery is  expected to  have measurable  clinical value  as
compared to the existing delivery method. The Company generally selects products
for reformulation that treat indications which have relatively simple, clear-cut
clinical end-points. Most of the Company's product candidates are reformulations
of  existing compounds  approved by the  FDA and the  Company's delivery systems
usually contain  inactive  ingredients that  are  generally recognized  as  safe
(GRAS)  for food use as  determined by the FDA  or are inactive ingredients that
the Company believes are safe for such use. Therefore, the Company believes that
the development  process for  its products  may  be expedited  and some  of  the
regulatory  approval risks may be reduced. In addition to reformulating existing
compounds, the Company also  intends to seek  arrangements with other  companies
developing  pharmaceutical products based  on new molecular  entities to use the
Company's drug delivery systems to formulate these products.
 
DRUG DELIVERY SYSTEMS
 
    Many  pharmaceutical  products   on  the  market   are  administered   using
conventional  oral,  injectable and  other  delivery methods  that  have certain
limitations. For example,  injections are  uncomfortable and  frequently can  be
given  only in a hospital or  physician's office and, accordingly, are generally
not  suitable  for  home  use.  Conventional  immediate-release   pharmaceutical
compounds  can  initially produce  higher drug  levels  in blood  than required,
increasing risks of side effects and subsequently producing lower drug levels in
blood than are therapeutically  optimal as the drug  is metabolized and  cleared
from  the body.  While some  of these  problems can  be alleviated  through more
frequent administration of lower doses  or continuous infusions, these modes  of
drug  therapy can  increase costs  and can  result in  patient inconvenience and
patient noncompliance.
 
    Advanced  drug  delivery  technologies  are  designed  to  allow  for   more
consistent  and  appropriate drug  levels in  the bloodstream  than conventional
methods of  drug  delivery, thereby  usually  improving a  drug's  efficacy  and
reducing  its side  effects. Sustained-release delivery  technologies also allow
for  the  development  of  dosage  forms  that  reduce  the  need  for  frequent
administration,   thus   improving  patient   compliance.   Additionally,  these
technologies may  permit  the  more  convenient  oral  delivery  of  drugs  that
otherwise could only be delivered by injection.
 
    The  Company  believes  that, for  most  indications, oral  delivery  is the
preferred method  of administration  and  that once-  or twice-a-day  dosing  is
convenient  and results in greater patient compliance than more frequent dosing.
The Company uses  a variety of  oral technologies for  the sustained-release  of
drugs  aimed at  controlling the  pattern of  drug delivery.  These technologies
include multiparticulate formulations that  use a variety of  controlled-release
coatings  and  sustained-release matrix  tablet  technologies. In  addition, the
Company has developed  its Peptitrol  drug delivery systems,  which enhance  the
oral delivery of hard-to-deliver pharmaceutical products by using materials that
increase absorption of a compound from the gastrointestinal tract.
 
                                       24
<PAGE>
    In reformulating hard-to-deliver pharmaceutical compounds, the Company seeks
to  improve the "bioavailability" of a  drug. Bioavailability, which is the rate
and extent  to which  the  active ingredient  of a  drug  is absorbed  into  the
bloodstream  and  becomes  available at  the  site  of action,  is  an important
component of the determination  of the effectiveness of  a drug. The Company  is
seeking  to increase the bioavailability  of certain hard-to-deliver drugs using
its Peptitrol delivery systems.
 
    The Company also designs controlled-release reformulations through which  it
seeks  to  develop  formulations  which  have  more  convenient  dosing  but are
bioequivalent to the existing  drug in order to  expedite the regulatory  review
process and the time for the development of a commercial pharmaceutical product.
When  the administration  of one compound  results in  the same bioavailability,
peak drug concentration and time to reach peak concentration in the blood as the
already FDA-approved drug, the compounds are said to be "bioequivalent."
STRATEGY
 
    PRODUCT SELECTION.  The Company's strategy in selecting its current  product
candidates  has been to select a  pharmaceutical product for reformulation based
on its analysis of the potential market and the likely time and expense required
to  develop  the  reformulated  pharmaceutical  product.  The  Company   selects
pharmaceutical  products for  reformulation that  have a  significant commercial
market, that are off-patent or that have patent protection expiring prior to the
expected market introduction of the  Company's product and where enhancement  of
the method of delivery is expected to have measurable clinical value as compared
to  the existing  delivery method.  The Company  generally selects  products for
reformulation that  treat indications  that  have relatively  simple,  clear-cut
clinical  end-points,  which  the  Company  believes  should  result  in  a more
straightforward development  and  regulatory  review  process.  In  addition  to
reformulating  existing compounds, the Company also intends to seek arrangements
with other companies developing pharmaceutical  products based on new  molecular
entities to use the Company's drug delivery systems to formulate these products.
 
    SELECTION  OF DRUG DELIVERY  SYSTEM.  Instead  of focusing on  a single drug
delivery system, the  Company has  developed an expertise  in a  number of  drug
delivery  technologies. The  Company selects  the drug  delivery system  that it
believes will optimize  delivery and  address the  clinical needs  that are  not
being  met  by existing  formulations.  The drug  delivery  systems used  by the
Company generally do  not chemically  modify the compounds  being delivered  and
usually contain inactive ingredients that are GRAS for food use as determined by
the  FDA or are inactive ingredients that the Company believes are safe for such
use. Therefore,  the  Company believes  that  the development  process  for  its
reformulated products may be expedited and some of the regulatory approval risks
may be reduced.
 
    SCREENING.   Because of  the time and expense  involved in clinical testing,
the Company seeks to optimize each  reformulation of a drug before such  testing
begins.   The  Company   has  developed   efficient,  high-throughput  screening
technologies  to  evaluate  specific  drug  delivery  approaches.  The   Company
generally  uses  these  screening  systems to  rapidly  and  systematically test
different reformulations of  a compound  to determine the  formulation with  the
greatest chance of success.
 
    COMMERCIALIZATION.   The Company  generally intends to  develop its products
and commence  clinical testing  in  humans and  then  to seek  collaborators  to
undertake  further testing, obtain  regulatory approval, manufacture, distribute
and market such  products. The Company  intends to evaluate  each product  under
development to determine the optimal time for seeking a collaborator. Generally,
the  Company  believes that  the  optimal time  to  seek collaborators  is after
successful results from the  first bioavailability studies  in humans have  been
obtained. The Company believes that this is the stage in the development process
which  will allow the  Company to obtain  the most favorable  terms for up-front
licensing fees, milestone payments  and royalties in  relation to the  Company's
costs for developing the product.
 
PRODUCTS IN DEVELOPMENT
    The  Company currently has 12  product candidates, one for  which an NDA was
accepted for filing by the FDA on June 1, 1996 and one of which is in Phase  III
clinical  trials.  The  Company has  been  concentrating its  recent  efforts on
developing and commercializing Carbatrol for the treatment of epilepsy and, to a
lesser extent, on the development of Selegiline SR for the treatment of  cocaine
craving,  Nifedipine SR and Acyclovir CD. During the next two years, the Company
expects to  focus substantial  efforts  to support  the 505(b)(2)  NDA  approval
process  for  Carbatrol and  market introduction  of  Carbatrol. In  addition to
Carbatrol, the Company intends to focus  most of its development efforts  during
the next year on Nifedipine SR and Acyclovir CD.
 
                                       25
<PAGE>
    The  following table lists  each of the Company's  12 product candidates and
its intended therapeutic indication, method  of drug delivery and current  stage
of  development. There can  be no assurance  that any of  these products will be
developed successfully or approved by the FDA in a timely manner.
 
<TABLE>
<CAPTION>
   PRODUCT CANDIDATE              INDICATION             DRUG DELIVERY TECHNOLOGY        DEVELOPMENT STAGE(1)
- -----------------------  ----------------------------  ----------------------------  ----------------------------
<S>                      <C>                           <C>                           <C>
Carbatrol                Epilepsy                      Oral sustained-release        505(b)(2) NDA accepted for
                                                                                      filing by the FDA on June
                                                                                      1, 1996/
                                                                                      licensed to Athena
Selegiline SR            Cocaine craving and           Oral sustained-release        Phase III commenced in
                          withdrawal                                                  November 1994
Selegiline SR            Parkinson's Disease           Oral sustained-release        Ready to enter Phase III
BChE Injectable          Cocaine overdose              Injectable                    Preclinical safety and
                                                                                      efficacy studies
                                                                                      substantially completed/
                                                                                      licensed to Rhone-Poulenc
                                                                                      Rorer
BChE Injectable          Post-surgical apnea           Injectable                    Preclinical safety and
                                                                                      efficacy studies
                                                                                      substantially completed/
                                                                                      licensed to Rhone-Poulenc
                                                                                      Rorer
Acyclovir CD             Viral infection               Peptitrol/sustained-release   Formulation development
DHE IR                   Migraine headache             Transmucosal                  Formulation development
                                                        immediate-release/
                                                        Peptitrol
Alprazolam TD            Anxiety                       Transdermal sustained-        Formulation development
                                                        release
Lorazepam TD             Anxiety                       Transdermal sustained-        Formulation development
                                                        release
PI 181.2 TD              Emesis                        Transdermal sustained-        Formulation development
                                                        release
Nifedipine SR            Cardiovascular disease        Oral sustained-release        Formulation development
Insulin CD               Diabetes                      Peptitrol                     Formulation development
</TABLE>
 
- ------------------
 
(1) The tests required by  the FDA before approval  of a pharmaceutical  product
    are generally divided into three categories. "Phase I clinical trials" refer
    to  the first phase of human pharmaceutical trials required to gain evidence
    of safety  and to  characterize the  pharmacokinetic and/or  pharmacodynamic
    profile  of  a drug.  "Phase  II clinical  trials"  are designed  to provide
    evidence of  efficacy, dose  response  and safety  in  a limited  number  of
    patients  with  the  targeted  disease.  "Phase  III  clinical  trials"  are
    generally designed to provide evidence of the efficacy and further safety of
    a compound in a large number of patients with the targeted disease. See  "--
    Government Regulation."
 
    "Preclinical  safety and efficacy  studies" are conducted  in the laboratory
    using animal  models to  evaluate the  potential safety  and efficacy  of  a
    product.
 
    "Formulation development" refers to the process of developing a prototype of
    a drug using a variety of materials to achieve a desired pattern of delivery
    of the drug and screening and optimizing the formulation.
 
                                       26
<PAGE>
     CARBATROL:     Carbatrol  is  an  oral,  controlled-release,  twice-per-day
formulation of carbamazepine for the treatment  of epilepsy. A major problem  in
the treatment of epilepsy is patient noncompliance with treatment regimen, which
often  may be  caused by frequent  daily dosing requirements  or unpleasant side
effects. A consequence of patient noncompliance is a greater risk of  developing
seizures.   Utilizing  a  novel  multiparticulate  oral  drug  delivery  system,
Carbatrol consists  of three  different  types of  pellets incorporated  into  a
capsule.  The Company  believes Carbatrol has  the potential  to improve patient
compliance since  its twice-a-day  dosing regimen  is more  convenient than  the
dosing  requirements  of  currently marketed  immediate-release  formulations of
carbamazepine, which should be taken three to four times a day. Carbatrol 200 mg
and 300 mg capsules  are designed to  deliver steady blood  levels of the  drug,
both  during the day  and at night.  Finally, Carbatrol offers  the potential of
being administered orally as a capsule, or sprinkled on the food of patients who
have difficulty swallowing  (e.g., young children,  the elderly); however,  such
use  is specifically  subject to  FDA approval. In  1994, a  patent covering the
Company's formulation of Carbatrol was issued.
 
    Approximately one  percent of  the population  in the  United States  (e.g.,
2.0-2.5  million  people)  suffers from  epilepsy.  There are  several  types of
seizures associated with epilepsy. Carbamazepine is a drug of choice in treating
two types of  epileptic seizures,  complex partial  and secondarily  generalized
tonic-clonic  seizures  (occurring  in approximately  one-half  of  all epilepsy
patients). In  1993, three  products --  CIBA-Geigy's Tegretol  (carbamazepine),
Warner   Lambert's   Dilantin  (phenytoin)   and  Abbott's   Depakene/  Depakote
(valproate) accounted for  approximately 70%  of the  prescriptions written  for
anti-convulsants.
 
    In   1993,  U.S.  sales  of  carbamazepine   were  $142  million,  of  which
approximately 80% represented sales of Tegretol. Since 1993, three new  products
have  been introduced --  Carter Wallace's Felbatol,  Warner Lambert's Neurontin
and Glaxo Wellcome's Lamictal.  The latter two of  these products are  indicated
for  use as adjunct  therapy in the  treatment of complex  partial seizures. The
Company is aware  that CIBA-Geigy  received FDA approval  on March  25, 1996  to
market  Tegretol XR, an extended-release formulation of carbamazepine permitting
twice-a-day dosing,  and has  announced  a possible  third quarter  1996  market
introduction  of the  product. Carbatrol,  should it  be approved,  will compete
directly in the marketplace with Tegretol XR.
 
    The  Company  completed   a  Phase  II/III   double  blind,  double   dummy,
placebo-controlled  clinical  trial  in  24 patients  with  epilepsy,  which the
Company  believes  demonstrated  that  Carbatrol   given  every  12  hours   was
bioequivalent  with Tegretol  given every six  hours. In 1995,  the Company also
completed a multi-center Phase III  efficacy/safety study of Carbatrol. In  this
study,  75% of the patients furnished Carbatrol did not have a level of seizures
requiring withdrawal from  the study as  compared to  20% of the  patients in  a
control  group. The  Company believes that  the study showed  that Carbatrol was
statistically significantly  more efficacious  than the  control medication.  In
1996,  the Company completed an additional  multi-center Phase III safety study.
To date, the Company  has documented no  serious treatment-related adverse  side
effects  from  Carbatrol. The  Company's 505(b)(2)  NDA which  was based  on the
bioequivalence of its product to Tegretol, was accepted for filing by the FDA on
June 1, 1996.
 
    In July 1996, the Company  licensed the exclusive worldwide marketing,  sale
and  distribution rights relating  to Carbatrol to Athena.  Athena has agreed to
fund  all  future  costs  of   development  of  Carbatrol.  See  "--   Licensing
Agreements."
 
    SELEGILINE  SR FOR COCAINE  CRAVING AND WITHDRAWAL:   Selegiline SR, an oral
sustained-release formulation  of  selegiline, a  drug  currently used  for  the
treatment  of  Parkinson's  Disease, is  being  developed  by the  Company  as a
medication  to  reduce  craving  for   cocaine.  Selegiline  SR,  a   once-a-day
formulation,  uses  the  Company's oral  sustained-release  delivery technology.
Since there  are no  adequate animal  models for  cocaine craving,  the  Company
selected selegeline for clinical evaluation based on the pharmacology of cocaine
and  the  presumed  mechanism  of action  of  selegeline.  Cocaine,  among other
actions, increases levels  of the  neurotransmitter dopamine in  the brain.  The
Company believes that, in chronic cocaine users, the levels of dopamine decrease
below  normal levels in the  absence of cocaine. The  Company also believes that
such decreased  levels  of  dopamine may  lead  to  a craving  for  cocaine  and
withdrawal symptoms. Selegiline
 
                                       27
<PAGE>
elevates  dopamine levels by inhibiting the enzyme, monoamine oxidase B (MAO-B),
which degrades dopamine. The Company believes that this increase in dopamine may
suppress the craving for cocaine and the symptoms of withdrawal.
 
    The  National  Institute   on  Drug  Abuse   ("NIDA")  has  estimated   that
approximately  five million  people in the  United States used  cocaine at least
once during 1992 and approximately 1.3 million people used cocaine at least once
a month during such  year. The Company believes  that many of these  individuals
could  benefit from treatment.  Despite the need for  an effective medication to
reduce physiological  craving  and serve  as  part of  an  integrated  treatment
program,  no such  product exists. The  Company believes that  Selegiline SR, if
safe and effective, could be used in treatment programs as part of an integrated
approach for treatment of cocaine addiction.
 
    Since there are no adequate animal  models for this indication, the  Company
proceeded  directly into clinical studies in  humans to evaluate Selegiline SR's
safety and efficacy. A Phase II  safety/drug interaction study of Selegiline  SR
and  cocaine was conducted  in a limited  number of cocaine  addicts. The study,
supported by NIDA, showed no problematic effects when cocaine and Selegiline  SR
were  administered together. In November 1994, the Company commenced a Phase III
multi-center clinical trial of Selegiline SR as a cocaine craving reducer, which
is being funded by  NIDA. The clinical  portion of this  trial was completed  in
December  1995. This Phase III trial will  be the first indication of Selegiline
SR's potential efficacy. If  Selegiline SR proves to  be effective, the  Company
plans  to seek a collaborative partner for  the remainder of the development and
testing of  this product.  In 1996,  a patent  was issued  to the  Company  with
respect to its formulation of Selegiline SR.
 
    SELEGILINE  SR  FOR PARKINSON'S  DISEASE:   The  Company is  also developing
Selegiline SR for the treatment of Parkinson's Disease. Selegiline, marketed  as
Eldepryl  by  Somerset/Sandoz,  is  currently  indicated  for  the  treatment of
Parkinson's Disease as an adjunct  to levodopa therapy. Orphan Drug  exclusivity
for  the use of  Eldepryl for this  indication expires in  1996. Selegiline is a
selective inhibitor of  the enzyme monoamine  oxidase type B  (MAO-B), which  is
responsible  for the degradation  of dopamine in the  human brain. By inhibiting
MAO-B, selegiline increases dopamine levels, thereby potentiating and prolonging
the effect  of  levodopa,  which is  the  primary  drug currently  used  in  the
treatment  of  Parkinson's Disease.  Certain  studies have  also  indicated that
selegiline may be effective as monotherapy in early Parkinson's Disease.
 
    There are approximately  500,000 patients  with Parkinson's  Disease in  the
United   States.  In  1994,  the  U.S.  market  for  selegiline  (Eldepryl)  was
approximately $84 million.
 
    Selegiline SR is designed  to provide more  convenient dosing than  Eldepryl
(once versus twice-a-day). The Company has completed a Phase I clinical study of
Selegiline  SR,  which the  Company believes,  demonstrated that  it selectively
inhibits MAO-B  and that  it has  equivalent bioavailability  to Eldepryl  given
twice-a-day. The Company anticipates that if it enters into an agreement for the
development  and testing  of Selegiline SR  for cocaine  craving, development of
Selegiline SR for  Parkinson's Disease will  also be included.  The Company  has
received a patent in 1996 with respect to its formulation of Selegiline SR.
 
    BCHE  INJECTABLE  FOR  COCAINE  OVERDOSE:    The  Company  is  developing an
injectable form of  BChE as  an antidote  for use  in the  treatment of  cocaine
overdose.  BChE is an enzyme  found principally in human  blood plasma that acts
rapidly to metabolize cocaine.  The Company's BChE  Injectable formulation is  a
highly  stable  solution  that can  be  stored  at room  temperature,  making it
convenient for  use in  emergency rooms  and emergency  vehicles.  Historically,
there have been approximately 100,000 emergency room visits in the United States
each  year  for cocaine  overdose. There  is currently  no antidote  for cocaine
overdose and current therapies focus on the treatment of its symptoms.
 
    The Company has completed preclinical safety and efficacy studies funded  by
grants  from  NIDA,  which the  Company  believes  showed BChE  to  be  safe and
well-tolerated in animal  models. These  studies showed  no effects  of BChE  on
cardiovascular  and central nervous system  parameters or general behavior. They
also showed  that BChE  significantly reduced  the development  of seizures  and
death in animals given large doses of
 
                                       28
<PAGE>
cocaine.  Preclinical  toxicity  and  viral  inactivation  studies  need  to  be
completed prior to submission of an Investigational New Drug ("IND") filing  for
this  product. Clinical testing cannot  begin until the Company  files an IND to
which the FDA does not object.
 
    A patent  was issued  in January  1994 covering  the Company's  process  for
obtaining  BChE  derived  from  human  plasma.  See  "--  Patents,  Licenses and
Proprietary Rights." In March 1992, the FDA granted Orphan Drug designation  for
the  use of  the BChE in  the reduction and  clearance of toxic  blood levels of
cocaine encountered during a drug overdose. See "-- Government Regulation."
 
    In August 1994, the Company licensed exclusive, worldwide rights to develop,
produce and  market its  two BChE  Injectable products  to Rhone-Poulenc  Rorer.
Rhone-Poulenc   Rorer  has  the  responsibility  for  conducting  the  necessary
preclinical  and   clinical   studies,  obtaining   regulatory   approvals   and
manufacturing  and  marketing  the  product worldwide.  The  Company  will, upon
request, provide consultation to  Rhone-Poulenc Rorer pursuant  to the terms  of
the license agreement. See "-- Licensing Agreements."
 
    BCHE  INJECTABLE  FOR  POST-SURGICAL  APNEA:    The  Company  has  also been
developing BChE Injectable as a  treatment for post-surgical apnea, a  condition
that  sometimes results in  death. Anesthesiologists use  muscle blocking agents
such as succinylcholine or mivacurium  in connection with the administration  of
general  anesthesia to patients undergoing surgery. After surgery, most patients
resume breathing on their own because  plasma BChE, which is naturally found  in
the  blood, inactivates the neuromuscular blocker over a period of time. A small
number of patients who have BChE  deficiency, which can be genetic or  acquired,
do  not resume  breathing on  their own  and require  mechanical ventilation. In
addition, BChE could be  useful in those  situations where the  anesthesiologist
may  wish  to have  control  over neuromuscular  blockade  (such as  with failed
intubation, interrupted surgery, or surgery  involving high risk patients).  The
Company  estimates that there are approximately  30,000 surgical patients in the
United States each year with a genetic or an acquired BChE deficiency.
 
    There is currently  no adequate treatment  for post-surgical apnea.  Current
treatments  include ventilating  the patient or  using neostigmine. Neostigmine,
although  effective  in  certain  situations,  is  ineffective  during  complete
neuromuscular  paralysis  with mivacurium.  The Company  believes that  its BChE
Injectable product may be useful in these circumstances.
 
    The Company has completed  preclinical studies suggesting  BChE is safe  and
effective  in  reversing neuromuscular  blockade. The  Company has  been granted
Orphan Drug Designation for  BChE Injectable in  the treatment of  post-surgical
apnea.  Such designation, however, does not assure  that the FDA has not granted
or will not grant orphan drug designation to similar products under  development
nor  does it assure  that the Company  or its licensee  will receive or maintain
marketing exclusivity  nor  that  it  may  be  blocked  from  the  market  by  a
competitor's  product.  See "Business  --  Government Regulations."  The license
granted to Rhone-Poulenc Rorer  to develop, produce  and market BChE  Injectable
also  applies  to BChE  Injectable for  post-surgical  apnea. See  "-- Licensing
Agreements."
 
    ACYCLOVIR  CD  FOR   VIRAL  INFECTION:     The  Company   is  developing   a
controlled-release formulation of acyclovir, a compound used in the treatment of
viral  infections. The Company's formulation uses its Peptitrol technologies and
is designed  to  enhance  oral  bioavailability  and  to  be  administered  less
frequently (e.g., once or twice-a-day). Acyclovir is currently available in oral
form  (tablets, capsules or as a suspension), as a topical application and as an
injectable. The oral  formulations are  indicated for the  treatment of  initial
episodes  and management of recurrent episodes  of genital herpes infections and
acute treatment of herpes  zoster ("shingles"). In addition  to these uses,  the
injectable  is approved for the treatment of herpes simplex encephalitis and for
use in immunocompromised  patients (e.g., AIDS  and transplantation  patients.).
Acyclovir,  marketed  by  Glaxo  Wellcome as  Zovirax,  is  the  largest selling
antiviral drug, with 1994  U.S. sales of  approximately $569 million.  Acyclovir
will be off-patent in 1997.
 
    While  current oral  formulations of  acyclovir allow  the use  of acyclovir
outside of the institutional setting,  there are problems associated with  these
formulations.  Acyclovir is poorly and erratically  absorbed (i.e., about 10% to
20% of the dose is absorbed), and bioavailability decreases with increasing dose
levels.  Therefore,  in  certain  circumstances,   the  drug  may  need  to   be
administered in very large doses
 
                                       29
<PAGE>
(e.g.,  600-4000 mg per day). In addition, the drug may need to be given several
times a day (e.g., every four hours, five times a day). This profile can  result
in  poor patient compliance that can,  in turn, compromise efficacy. The Company
believes that these limitations can be addressed by a formulation that has  good
oral  bioavailablity and  that can  be dosed  more conveniently  (e.g., once- or
twice-a-day).
 
    The Company  has  substantially  completed formulation  development  on  two
prototypes  of Acyclovir CD.  The Company has  observed substantial increases in
cellular transport  in  its  Peptiscreen model  using  these  formulations.  The
Company  intends to file  an IND for  Acyclovir CD during  1997. The Company has
applied for  a patent  covering one  of  its formulations  of Acyclovir  CD  and
intends to file a patent application covering the other formulation of Acyclovir
CD,  which  is  currently  the  Company's  lead  formulation  for  this  product
candidate.
 
    DHE IR FOR MIGRAINE HEADACHE:  Using its Peptitrol technologies, the Company
is designing  a  transmucosal  formulation  of DHE  for  treatment  of  migraine
(vascular)  headache by means of  a buccal or sublingual  tablet or a sublingual
spray.
 
    Approximately 10% of the  population (i.e., 25  million people) suffer  from
migraine  headache. Of these, the Company believes that only about 40% (i.e., 10
million people) seek treatment. Currently marketed drugs can be classified  into
those  used  to: (a)  terminate headache,  (b) prevent  headache or  (c) provide
symptomatic relief. Despite the large potential market and the availability of a
large number of medications, none is ideal. Many products have poor efficacy  or
side  effect profiles. In addition,  the means of administration  of many of the
available medications (e.g., injectables  or suppositories) are poorly  accepted
by patients.
 
    An  injectable  form of  DHE,  marketed as  DHE-45  by Sandoz,  is  a highly
effective medication  that  is  indicated  for  both  the  termination  and  the
prevention  of migraine headache. Sumatriptan,  indicated for the termination of
migraine headache, was introduced originally by Glaxo Wellcome as an injectable,
and in 1995 in  oral form. In 1994,  sumatriptan had sales in  the U.S. of  $241
million.  The Company  believes that the  headache market has  expanded with the
introduction of sumatriptan formulations  and could be  expanded further if  DHE
were  available in  a formulation that  could be  administered transmucosally or
orally instead of by injection.
 
    The current method of administering  DHE-45 by injection is poorly  accepted
by  patients and most patients need to see  their physician or go to a clinic or
hospital emergency room  for treatment. In  addition, a delay  in treatment  may
reduce  the potential efficacy  of DHE because the  longer the migraine headache
lasts, the more difficult it is to terminate. The formulation being developed by
the Company  is designed  for  administration at  first  sign of  migraine.  The
Company's  DHE product candidate could be  self-administered by the patient. The
transmucosal  approach  would  offer  the  additional  advantage  over  an  oral
formulation  of rapid absorption of the drug directly into the bloodstream (with
no first pass metabolism by the  liver), resulting in more rapid termination  of
the headache.
 
    The  Company  initiated a  Phase I  clinical study  of a  rapidly dissolving
buccal tablet  formulation  of DHE,  but  the results  of  this study  were  not
favorable.  Thereafter, the Company has used its Peptitrol drug delivery system,
which is  designed for  oral delivery,  to  develop a  new formulation  of  DHE.
Preliminary  screening in Peptiscreen has shown positive results in transport of
DHE formulations across cell lines, as well as from the gastrointestinal  tracts
of  animals. Because  of the  advantages of  transmucosal delivery,  the Company
intends to  initially focus  on transmucosal  delivery of  DHE. If  transmucosal
delivery  is not  successful, the  Company will focus  on oral  delivery of this
product. The  Company is  seeking  a collaborator  prior to  conducting  further
research and development of its DHE IR product.
 
    ALPRAZOLAM  TD AND LORAZEPAM  TD FOR ANXIETY:   The Company  is developing a
once-a-day transdermal formulation of alprazolam and of lorazepam, both of which
are benzodiazepine compounds for the  treatment of anxiety. Currently  available
medications  for the  treatment of anxiety  are immediate  release and, although
effective, result in fluctuating blood levels that the Company believes can lead
to product  dependence.  The  Company  has  utilized  its  transdermal  delivery
technology using flux enhancers to facilitate
 
                                       30
<PAGE>
delivery  of  both  alprazolam  and lorazepam  across  skin.  Alprazolam  TD and
Lorazepam TD,  the Company's  products under  development, are  both  once-a-day
transdermal  formulations,  designed  to  deliver  steady  blood  levels  of the
medication.
 
    Research conducted by  the American Psychiatric  Association indicates  that
8.3% of Americans (i.e. approximately 21 million people) suffer from anxiety. In
1992, $1.2 billion of anti-anxiety agents were marketed in the United States and
Canada,  and $2.4 billion were marketed worldwide. Alprazolam (marketed as Xanax
by Upjohn) was the largest selling anti-anxiety medication in the United States,
with sales in 1993 of approximately $510 million, which sales fell significantly
in 1994 due to  sales of generic  versions of the  drug. Lorazepam (marketed  as
Ativan by Wyeth Ayerst) is the second largest selling benzodiazepine medication,
with 1994 sales of $148 million in the United States.
 
    Although  the currently  marketed anti-anxiety  products are therapeutically
effective, they have frequent dosing requirements (typically three to four times
a day),  the potential  for adverse  side effects  (attributable to  peak  blood
levels seen with administration of immediate-release products) and the potential
for  patients becoming dependent on the  anti-anxiety product (which the Company
believes is related to  the sharp peaks  and troughs in  blood levels seen  with
immediate-release  formulations). The Company believes  that these drawbacks can
be overcome with a sustained-release, long-acting (e.g., once-a-day) transdermal
product. Should undesirable side effects  occur, delivery of the medication  can
be stopped by simple removal of the transdermal patch.
 
    The  Company is in the process of formulating prototypes of Lorazepam TD and
Aprazolam TD to deliver the required dosage in transdermal screening models. The
Company has developed  a prototype  of Lorazepam TD  that is  of a  cosmetically
acceptable size and that delivers the proper drug dosage but further development
work  is  necessary  in  order  to control  the  stability  of  the formulation.
Preclinical testing in animal models has  not yet commenced. The development  of
Lorazepam  TD and Alprazolam TD is still in  the very early stages and there can
be no assurance  that the  Company will be  successful in  formulating a  stable
formulation of a cosmetically acceptable size.
 
    PI   181.2  TD  FOR  EMESIS:    The  Company  is  developing  a  long-acting
(once-a-day) transdermal  formulation  of  an  FDA-approved  compound  that  the
Company   believes  has  anti-emetic  (anti-vomiting)  properties.  The  Company
believes that  this compound  (which it  calls PI  181.2) could  be used  for  a
variety  of  indications, including  chemotherapy-induced  emesis, post-surgical
nausea, pre-surgical nausea prophylaxis and weight maintenance in patients  with
AIDS.  The Company  estimates that  there are  2.5 million  episodes annually of
chemotherapy in the  United States requiring  administration of an  anti-emetic.
Post-operative  nausea occurs  in about  one-third of  the estimated  25 million
surgical procedures  performed  annually  in the  United  States.  Additionally,
weight  loss is a significant complication in  many AIDS patients, and an easily
administered, well-tolerated anti-emetic  is expected to  have benefits in  this
area.
 
    Most  of the products sold in this  area are off-patent medications that are
administered orally or by injection. The  major new entrant into this market  is
Zofran,  an injectable  marketed by  Glaxo Wellcome.  Both injectables  and oral
medications have  certain drawbacks  for this  indication. Injectables  must  be
given  every few hours by  a caregiver, are uncomfortable  and can exacerbate an
already traumatic  procedure. Administration  of  oral medications  can  trigger
emesis  (vomiting)  and,  if emesis  occurs  subsequently, it  is  impossible to
determine how much of the anti-emetic the patient absorbed. Transdermal delivery
is the preferred route of administration because a patch can be easily  applied,
either  by a caregiver in the hospital setting or by the patient at home, making
it more cost effective  than an injectable.  Transdermal delivery also  provides
steady blood levels and a transdermal patch can be removed when desired.
 
    The  Company  has conducted  experiments with  different flux  enhancers for
transdermal delivery of PI  181.2 TD and has  found drug delivery vehicles  that
deliver targeted amounts of the drug through human skin samples. The development
of  PI 181.2 TD is still in the very  early stages and there can be no assurance
that the Company  will be successful  in formulating a  stable formulation of  a
cosmetically acceptable size.
 
    NIFEDIPINE  SR  FOR  CARDIOVASCULAR  DISEASE:    The  Company  is conducting
research for the purpose  of developing a generic  version of a once-a-day  oral
sustained-release formulation of nifedipine. Nifedipine is a
 
                                       31
<PAGE>
calcium  channel  blocker used  for the  treatment  of hypertension  and angina.
Nifedipine is marketed as Procardia by Pfizer in the United States and as Adalat
by Bayer  AG  both  inside and  outside  of  the United  States.  Procardia  was
originally  introduced as a three to four  times a day product for the treatment
of angina.  Subsequently, Pfizer  introduced Procardia  XL, an  extended-release
tablet  that has expanded labeling  (as a treatment for  hypertension as well as
angina) and  is administered  once a  day.  In 1993,  sales of  calcium  channel
blockers were estimated at $2.4 billion in the United States. In 1994, Procardia
XL, the leading calcium channel blocker, had approximately $1.2 billion in sales
in the United States.
 
    The  Company believes  that there  is a  significant market  opportunity for
products that  are bioequivalent  to  Procardia XL.  The Company  is  conducting
research  for  the  purpose  of  identifying  and  developing  a  formulation of
nifedipine that is bioequivalent  to Procardia XL, but  which does not  infringe
Pfizer's existing patents on Procardia XL. The Company is aware that a number of
companies  are also attempting to develop  generic formulations of Procardia XL.
Although the patent  on the  compound nifedipine  has expired,  Pfizer has  been
issued  patents with respect to its  once-a-day formulation of nifedipine, which
it markets as Procardia XL. There can  be no assurance that the Company will  be
successful  in  developing  a  generic  formulation  that  is  bioequivalent  to
Procardia XL  and  that does  not  infringe  Pfizer's patents.  If  the  Company
successfully  develops the  reformulation, the  Company expects  that it  or its
licensee will file an ANDA with the FDA with respect to the reformulation. Since
the filing  of  an  ANDA  for a  product  covered  by  a patent  is  an  act  of
infringement,  the  Company believes  Pfizer would  file  a lawsuit  against the
Company and  its licensee,  if any,  if  it believed  it had  a claim  that  the
Company's formulation was covered by Pfizer's patents. The Company is also aware
that  Pfizer has raised objections  with the FDA in  connection with attempts by
other developers of generic  sustained-release nifedipine to  file ANDAs on  the
basis  of bioequivalence to Procardia XL and Pfizer may institute other legal or
regulatory  challenges   against   developers   of   sustained-release   generic
nifedipine. See "Risk Factors -- Dependence on Patents and Proprietary Rights."
 
    INSULIN  CD FOR  DIABETES:  The  Company is  in the process  of evaluating a
microemulsion formulation  of  insulin  using its  Peptitrol  technologies.  The
Company's product candidate is designed to be administered orally as a liquid or
in   a  soft  gelatin  capsule,   with  either  immediate  or  sustained-release
characteristics. Diabetes mellitus  is the  most common  endocrine disease.  The
American Diabetes Association estimates that 14 million Americans have diabetes,
only  half  of which  are diagnosed;  about  10% have  insulin-dependent disease
(IDDM) and 90% have non-insulin-dependent  disease (NIDDM). Insulin is  required
for treatment of all patients with IDDM and many patients with NIDDM.
 
    In  preliminary tests using the Company's Peptiscreen model, a microemulsion
formulation of insulin has exhibited increased cellular transport. A significant
number of  companies have  attempted to  develop an  oral insulin  product  and,
because  of  the  difficulties of  development,  have not  been  successful. The
development and testing of the Company's formulation of insulin is still in  the
very  early  stages and  there  can be  no assurance  that  the Company  will be
successful in developing a product based on this research. The Company has filed
a patent application on its formulation of insulin.
 
PEPTITROL AND PEPTISCREEN TECHNOLOGIES
 
    The Company  has  developed  a  portfolio of  drug  delivery  and  screening
technologies designed to produce optimal delivery of a particular pharmaceutical
product  for  a given  indication.  These technologies  include  its proprietary
Peptitrol systems  for  the oral  delivery  of hard-to-deliver  compounds,  oral
controlled-release and sustained-release delivery, transmucosal delivery through
tissues in the oral cavity and transdermal delivery.
 
    The   Company  has   developed  its  proprietary   Peptitrol  drug  delivery
technologies for the  enhanced oral delivery  of poorly absorbed  pharmaceutical
compounds   that   are   hard   to  deliver   or   have   poor   oral  bioavail-
ability, such as peptides and other large molecules. The Peptitrol drug delivery
systems use one  or more  hydrophobic or  hydrophilic materials  to protect  the
pharmaceutical  compound  from degradation  and  to increase  absorption  of the
compound from the gastrointestinal tract. The Company then uses its  Peptiscreen
cell  culture  screens to  rapidly test  formulations developed  using Peptitrol
technologies. Peptitrol consists of
 
                                       32
<PAGE>
several drug  delivery  approaches  --  a drug  delivery  system  consisting  of
hydrophobic materials to enhance absorption; a multilamellar system comprised of
alternating layers of hydrophobic and hydrophilic materials that can incorporate
the  compound  as well  as  sustained-release materials,  and  two microemulsion
systems.
 
    The Company  uses  its  Peptiscreen  system  to  systematically  screen  its
formulations. Peptiscreen permits high throughput screening of a large number of
formulations  to test the  extent to which various  formulations may be absorbed
from the gastrointestinal  tract and  which of  the formulations  may result  in
commercially acceptable levels of transport. The screens utilize cell lines that
mimic  different aspects of  the gastrointestinal mucosa.  One principal screen,
for example, uses cells  that grow and  differentiate, develop tight  junctions,
which  prevent most materials from passing between the cells, actively transport
glucose, develop a  brush border, and  have barrier properties,  all similar  to
gastrointestinal  cells. Different screens are used depending on the formulation
characteristics desired.
 
    The Company believes that its  Peptitrol systems have general  applicability
to  the  formulation  of  peptides  and proteins  (such  as  those  developed by
biotechnology companies), as well as  small molecular weight compounds (such  as
those  traditionally  developed by  pharmaceutical  companies). The  Company has
tested its  systems  in its  Peptiscreen  cell  cultures on  peptides  having  a
molecular  weight of up to approximately 5600 daltons, and the systems appear to
be able  to transport  peptides having  a  molecular weight  up to  this  level.
However,  the Company's testing is preliminary and  there can be no assurance of
the extent to which the  technology will prove to  be effective for peptides  or
other large molecules in clinical testing.
 
LICENSING AGREEMENTS
 
    On  August 25, 1994, the Company  and Rhone-Poulenc Rorer signed a worldwide
licensing agreement to develop BChE for use in the treatment of cocaine overdose
and the  reversal of  post-surgical apnea.  The agreement  grants  Rhone-Poulenc
Rorer  the exclusive right to develop, produce  and market, at its sole expense,
human pharmaceutical  or diagnostic  products that  contains BChE  as an  active
ingredient  for the diagnosis,  prevention or treatment of  any human disease or
medical condition. Under  the terms  of the  agreement, the  Company received  a
$2,000,000  license  fee  upon  execution  and  will  receive  certain milestone
payments and  royalties based  on  net sales.  Rhone-Poulenc Rorer  has  assumed
responsibility   for  the  further  preclinical  and  clinical  development  and
commercialization of this product and the  Company has agreed to assist in  such
development   by  providing  consultation,   at  the  request   and  expense  of
Rhone-Poulenc Rorer. Rhone-Poulenc Rorer has the right to investigate additional
indications for this product.
 
    On July 1,  1996, the Company  entered into an  exclusive license  agreement
with  Athena for  the worldwide marketing,  sale and  distribution of Carbatrol.
Carbatrol will  be marketed  (under the  name Carbatrol  or under  another  name
selected  by Athena)  in the United  States by  Athena and by  its affiliates or
sublicensees in the rest of the world. Under the agreement, Athena (i) will make
a $2.0 million payment within ten days of execution of the agreement, (ii)  will
fund all future development cost associated with Carbatrol which are approved by
a  steering committee, (iii) will make a milestone payment of up to $8.0 million
upon FDA  approval of  the Company's  Carbatrol NDA,  of which  $5.0 million  is
creditable against future royalty payments which may be earned on product sales,
and  (iv) will make future royalty payments to the Company based on net sales of
Carbatrol and sublicensing revenues. The  milestone payment is conditioned  upon
the  absence of any finding  of exclusivity for CIBA-Geigy's  Tegretol XR or any
actual or threatened proceeding seeking  such a finding. Further, the  agreement
may  be  terminated  in  Athena's discretion  under  certain  circumstances. The
Company is responsible initially for supplying Carbatrol to Athena. The  Company
has  entered into an exclusive  agreement with a third  party to manufacture the
pellets that contain the active ingredient of Carbatrol and has entered into  an
agreement  with  another third  party to  encapsulate  and package  the product.
Athena has agreed to be responsible for the costs under these agreements and for
the manufacture of Carbatrol after the expiration of these agreements. See "  --
Manufacturing."  Athena has been granted the right to purchase 220,000 shares of
Common Stock in this offering.
 
COMPETITION
 
    Most of the Company's  product candidates are  reformulations of drugs  that
will  be  off-patent when  the  Company's products  are  introduced. All  of the
Company's proposed products will face competition from
 
                                       33
<PAGE>
existing therapies,  more  traditional  forms  of  drug  delivery  and  advanced
delivery  systems  and  drugs being  developed  by others.  Competition  for the
development of drug delivery products is  intense and expected to increase.  The
Company is aware of a number of drug delivery companies and large pharmaceutical
companies  that develop  or market  sustained-release oral  dosage systems, have
developed transdermal drug delivery systems, transmucosal systems or have active
research and development programs in controlled-release methods. Many  companies
also  are developing  technologies for the  oral delivery of  peptides and other
poorly absorbed molecules. Most of the Company's competitors have  substantially
greater  financial resources and larger research and development staffs than the
Company, as well as substantially greater experience in developing products,  in
obtaining regulatory approvals and in manufacturing and marketing pharmaceutical
products.  There can be no assurance  that the Company will successfully develop
technologies and products that  are more convenient,  more effective, result  in
fewer  side effects  or are  more affordable than  those being  developed by its
competitors. Furthermore, there can be  no assurance that product  introductions
or developments by others will not render the Company's products or technologies
noncompetitive or obsolete or that patents issued to competitors may not prevent
the Company from pursuing certain products.
 
    The  Company  will compete  with  off-patent drug  manufacturers, brand-name
pharmaceutical companies  that  manufacture  or  market  off-patent  drugs,  the
original  manufacturers of brand-name drugs that  continue to produce such drugs
after patent  expirations or  introduce generic  or improved  versions of  their
branded products, drug companies developing formulations of off-patent drugs and
manufacturers  of new drugs that may  compete with the Company's formulations of
off-patent products and other drug delivery companies developing formulations of
off-patent drugs or new chemical entities. For example, CIBA-Geigy has developed
an extended-release formulation of Tegretol which was approved in March 1996 and
will compete directly with Carbatrol, if  and when it is approved. In  addition,
the  Company is aware of several  companies with significantly greater resources
that are seeking to develop generic formulations of sustained-release nifedipine
(Procardia XL).
 
    The  Company's  products  under  development  will  compete  with   existing
therapies for epilepsy, Parkinson's Disease, migraine headache, anxiety, emesis,
cardiovascular  disease,  viral  infection and  diabetes.  Specifically,  to the
extent that the active ingredient in the Company's products consist of available
compounds such as carbamazepine  or selegiline, the  Company's products will  be
competing  with the  brand-name product originally  making use  of the compound.
Generally,  brand-name  versions  of  pharmaceutical  compounds  have  a  market
advantage  over  other products  using the  same compound.  In addition,  to the
extent that the  manufacturers of  the brand-name  products seek  to develop  or
market  their own sustained-release  versions of products,  such as CIBA-Geigy's
extended-release formulation  of Tegretol,  the  Company may  find itself  at  a
competitive disadvantage by virtue of their ability to use the name-brand in the
advertising of their products.
 
    The  Company's competitive position also depends upon its ability to attract
and retain qualified  personnel, obtain patent  protection or otherwise  develop
proprietary  products or processes  and secure sufficient  capital resources for
the often lengthy period between technological conception and commercial sales.
 
MANUFACTURING
 
    The Company generally intends to develop its products and commence  clinical
testing  in humans and then to seek a collaborator to undertake further testing,
obtain regulatory approval,  manufacture, distribute and  market such  products.
The  Company  expects  that  its collaborators  will  assume  responsibility for
manufacturing, distribution and  marketing. If  the Company is  unable to  enter
into a collaborative arrangement for a particular product on acceptable terms or
enters  into a license agreement  where the licensee is  unwilling to assume the
responsibility for manufacturing, then the Company may assume responsibility for
manufacturing the  product.  The Company  has  no manufacturing  facilities  and
generally  plans to rely upon contract  manufacturers to manufacture its initial
products. The  Company  believes that  there  is currently  sufficient  capacity
worldwide  for the production of its  product candidates. The Company intends to
establish  manufacturing  arrangements  with  manufacturers  that  comply   with
FDA-mandated  cGMP requirements and other applicable regulations, although there
is no assurance that the Company will be able to do so.
 
                                       34
<PAGE>
    The Company has  contracted with Niro  Inc. ("Niro") for  the production  of
pellets  for Carbatrol. The  Company's agreement with Niro  provides for Niro to
act as  the exclusive  manufacturer of  carbamazepine pellets  according to  the
Company's   specification  for  a  minimum  period   of  three  years  from  the
commencement of production. The Company is obligated to order a minimum quantity
of pellets and  pay Niro a  fixed price per  kilogram of pellets  for the  first
three  years of production under  the agreement. Niro has  further agreed not to
manufacture any carbamazepine product for a third party so long as the agreement
is in effect. The agreement with Niro will automatically renew from year to year
on terms mutually agreed  upon not less  than two years  prior to such  renewal.
Niro must provide a minimum of two-years prior written notice of non-renewal and
the  Company must provide a minimum of  one-year prior notice of non-renewal. If
the Company cancels this  agreement prior to the  initial year of production  or
does  not give notice to  commence production on or  before October 1, 1996, the
Company may be required to reimburse  Niro for certain direct costs incurred  by
Niro. The Company has also entered into an agreement with The P.F. Laboratories,
Inc.  ("P.F.  Labs")  for  the encapsulation  and  packaging  of  Carbatrol. The
Company's agreement  with  P.F.  Labs provides  for  P.F.  Labs to  act  as  the
exclusive  encapsulator of  Carbatrol according to  the Company's specifications
and requirements. The Company is obligated to order a minimum number of capsules
from P.F. Labs at a fixed price for the first year of the agreement, which price
shall be subject to negotiation thereafter. Under its agreement with Athena, the
Company will  be  responsible  for  supplying  Carbatrol  through  its  contract
manufacturers  and Athena has agreed to pay  the costs of manufacture under such
contracts. Athena  is  obligated to  assume  responsibility for  manufacture  of
Carbatrol after expiration of these agreements.
 
    The  Company has no experience in  volume manufacturing. The Company intends
to establish and  maintain its own  quality control program  for certain of  its
products,  including a set  of standard operating  procedures designed to assure
that the Company's products are manufactured  in accordance with cGMP and  other
applicable  regulations.  Should  the  Company  need  or  elect  to  establish a
manufacturing facility, it  will require substantial  additional funds and  will
need to hire significant additional qualified personnel.
 
    The  Company's  revenues  from  BChE  are  dependent  upon  the  ability  of
Rhone-Poulenc Rorer to develop, produce, register and market the BChE Injectable
products and to obtain an adequate  supply of blood plasma necessary to  produce
commercial  quantities  of  BChE. Additionally,  plasma  suppliers  obtain their
supply from human  donors who  are limited  as to  the amount  and frequency  of
donations.  Should the supply of suitable  plasma donors decline, the ability of
Rhone-Poulenc Rorer  to  produce and  sell  BChE Injectable  products  could  be
adversely  affected. See "Risk  Factors -- Limited  Manufacturing Capability and
Experience" and "-- Uncertainty of Supply of BChE; Product Safety."
 
MARKETING
 
    The Company's  revenues from  BChE will  be dependent  upon the  ability  of
Rhone-Poulenc Rorer to develop and market the BChE Injectable products. Revenues
from  Carbatrol  will be  dependent upon  Athena's ability  to market,  sell and
distribute Carbatrol on its own  in the United States  and by its affiliates  or
sublicensees  in the rest of  the world. The Company  generally intends to enter
into  collaborative   arrangements  to   complete  development,   manufacturing,
distribution  and marketing of  its product candidates  or enter into agreements
for the distribution and marketing of the product. In either case, third parties
would be  primarily  responsible for  marketing.  However, in  the  future,  the
Company  may  co-promote  or retain  U.S.  marketing  rights to  certain  of its
products.  In  selecting   these  products,  the   Company  expects  to   target
concentrated  market segments that  can be addressed  adequately by a relatively
small sales force; however,  significant additional expenditures and  management
resources  will be required to develop an external sales force and implement its
marketing strategy if the Company decides to market products directly. There can
be no assurance that the Company's collaborators will be successful in marketing
products, or that the Company will  be able to establish a successful  marketing
force.  See "Risk Factors -- No  Marketing and Sales Capability; Dependence Upon
Third Parties for Marketing."
 
PATENTS, LICENSES AND PROPRIETARY RIGHTS
 
    The Company's policy is  to protect its technology  by, among other  things,
filing  patent applications for technologies and products it considers important
in   the    development   of    its   business.    In   addition    to    filing
 
                                       35
<PAGE>
patent  applications in the United States, the Company has filed, and intends to
file, patent applications in foreign countries on a selective basis. The Company
also relies on trade secrets,  unpatented know-how and technological  innovation
to develop and maintain its competitive position.
 
    In  1994, a patent expiring  in 2011 was issued  to the Company covering the
process for  obtaining  BChE from  plasma.  The Company  believes  that  another
approach  may be  available for producing  BChE using recombinant  methods. As a
result, other parties may be able to  manufacture BChE for any and all  purposes
without  infringing the Company's patent. In 1994, a patent expiring in 2011 was
also issued  covering the  formulation of  the Company's  Carbatrol product.  In
1995, two patents were issued based on the Company's Peptitrol technologies. One
of  the  patents,  which  expires  in  2014,  is  directed  to  a pharmaceutical
preparation of a drug which is poorly soluble in water and which is incorporated
into particles comprised  of hydrophobic  fatty acid ester.  The second  patent,
which  also expires in  2014, is directed  to a pharmaceutical  preparation of a
drug incorporated into particles formed  of alternate layers of hydrophobic  and
hydrophilic  materials. In addition,  in 1996, a patent,  which expires in 2015,
was issued covering the formulation of the Company's Selegiline SR product.
 
    Applications have also been filed for patents covering specific formulations
of acyclovir  and insulin  based on  the Company's  Peptitrol technologies.  The
Company  is  aware  of  other pharmaceutical  companies  that  are  working with
microemulsions or hydrophobic materials  for use in  drug delivery. The  Company
intends  to  prepare additional  patent applications  relating primarily  to its
transdermal products and products using  its Peptitrol technologies. Although  a
patent  has  a  statutory presumption  of  validity  in the  United  States, the
issuance of  a patent  is  not conclusive  as  to such  validity  or as  to  the
enforceable  scope of the claims  of the patent. There  can be no assurance that
the Company's issued patents or any  patents subsequently issued to or  licensed
by  the Company will not be successfully  challenged in the future. The validity
or enforceability of a  patent after its  issuance by the  patent office can  be
challenged  in litigation. If  the outcome of  the litigation is  adverse to the
owner of the patent, third parties may then be able to use the invention covered
by the patent, in some cases without payment. There can be no assurance that the
Company's patents will not be  infringed or successfully avoided through  design
innovation.
 
    There  can be no assurance  that patents or patent  applications owned by or
licensed to the Company will result in patents being issued or that, if  issued,
the  patents will afford protection against competitors with similar technology.
For  example,  other  companies   are  evaluating  microemulsion,   hydrophobic,
transdermal,  transmucosal and  sustained-release oral formulations.  It is also
possible that third parties may obtain  patent or other proprietary rights  that
may  be necessary  or useful to  the Company.  In cases where  third parties are
first to invent a  particular product or technology,  it is possible that  those
parties will obtain patents that will be sufficiently broad so as to prevent the
Company   from  using   certain  technology   or  from   further  developing  or
commercializing certain products. If licenses  from third parties are  necessary
but  cannot  be obtained,  commercialization of  the  related products  would be
delayed or prevented.  The Company is  aware of patent  applications and  issued
patents  belonging to competitors and  it is uncertain whether  any of these, or
other filed patent applications of which the Company may not have any knowledge,
will require  the Company  to alter  its potential  products or  processes,  pay
licensing fees or cease certain activities.
 
    The  Company's principal  products are reformulations  of existing products.
Therefore, patents, if any, issued to the Company will only cover the  Company's
formulation  of the product or the process for manufacturing the product. Others
may be able  to develop  formulations which  provide similar  advantages to  the
Company's, but which do not infringe the Company's patent. Additionally, patents
issued  or which may be issued in the  future with respect to Peptitrol or other
drug delivery systems  may not  be sufficiently  broad to  preclude others  from
developing  products that  compete with products  developed by  the Company. For
example, although the Company's issued patents and patent applications  relating
to Peptitrol may prevent competitors from developing products using formulations
covered  by the  Company's patents,  the patents  would not  completely preclude
other companies  from  formulating  drugs  using  these  technologies  or  other
technologies that could provide similar results.
 
    The Company's product candidates may conflict with patents that have been or
may  be granted to competitors, universities  or others. In addition, such other
persons could bring legal actions against the
 
                                       36
<PAGE>
Company claiming damages and  seeking to enjoin  manufacturing and marketing  of
the  affected products. If any  such actions are successful,  in addition to any
potential liability  for damages,  the Company  could be  required to  obtain  a
license  in order  to continue to  manufacture or market  the affected products.
There can be no assurance that the  Company would prevail in any such action  or
that  any license  required under  any such  patent would  be made  available on
acceptable terms. The Company believes that there may be significant  litigation
in  the industry regarding patent and other intellectual property rights. If the
Company becomes  involved  in  such litigation,  it  could  consume  substantial
resources.
 
    The  Company is conducting research to  identify and develop a reformulation
of nifedipine  which  is  bioequivalent  to  Procardia  XL,  without  infringing
Pfizer's  existing patents  on Procardia  XL. While  the patent  on the compound
nifedipine has  expired, Pfizer  has been  issued patents  with respect  to  its
once-a-day  formulation of nifedipine, which it  markets as Procardia XL. If the
Company successfully develops  a nifedipine reformulation,  the Company  expects
that  it or  its licensee will  file an  ANDA with the  FDA with  respect to the
reformulation. There can be no assurance that the Company will be successful  in
developing  a generic  reformulation that is  bioequivalent to  Procardia XL and
that does not  infringe Pfizer's  patents. Since  the filing  of an  ANDA for  a
product  covered by  a patent  is an act  of infringement,  the Company believes
Pfizer would file a lawsuit against the Company and its licensee, if any, if  it
believed  it had a claim that the  Company's formulation was covered by Pfizer's
patents. The good faith filing of a patent action could delay the approval of an
ANDA for a period  of up to  30 months or longer  if so ordered  by a court.  If
Pfizer  successfully  asserts  its patents,  the  Company may  be  enjoined from
selling its product until Pfizer's patents expire.
 
    The  Company  also  relies  on  unpatented  technology,  trade  secrets  and
information  and no  assurance can be  given that others  will not independently
develop substantially equivalent  information and techniques  or otherwise  gain
access  to the  Company's technology  or disclose  such technology,  or that the
Company can meaningfully protect its rights in such unpatented technology, trade
secrets and information. The Company requires each of its employees, consultants
and advisors to execute  a confidentiality agreement at  the commencement of  an
employment or consulting relationship with the Company. The agreements generally
provide  that  all  inventions conceived  by  the  individual in  the  course of
employment or in the providing of  services to the Company and all  confidential
information  developed by, or made  known to, the individual  during the term of
the relationship shall  be the exclusive  property of the  Company and shall  be
kept confidential and not disclosed to third parties except in limited specified
circumstances.  There can be  no assurance, however,  that these agreements will
provide meaningful  protection for  the Company's  information in  the event  of
unauthorized use or disclosure of such confidential information.
 
GOVERNMENT REGULATION
 
    The  Company's activities and products are subject to extensive and rigorous
regulation by a number  of governmental entities, especially  by the FDA in  the
United  States and by comparable authorities  in other countries. These entities
regulate, among  other  things,  research and  development  activities  and  the
testing,  manufacture, safety, effectiveness, labeling, storage, record keeping,
approval,  advertising,  promotion,  distribution  and  sale  of  the  Company's
products.  Product  development and  approval  within this  regulatory framework
takes a number of  years and involves the  expenditure of substantial  resources
and is often uncertain. Many products that initially appear promising ultimately
do  not reach the market because they are  not found to be safe or effective, as
demonstrated by testing required by government regulation during the development
process. In addition, there can be  no assurance that this regulatory  framework
will not change or that additional regulation will not arise at any stage of the
Company's  product development that may affect approval, delay an application or
require additional expenditure  by the  Company. Moreover, even  if approval  is
obtained,  failure to comply with present  or future regulatory requirements, or
new information  adversely reflecting  on  the safety  or effectiveness  of  the
approved  drug, can lead  to FDA withdrawal  of approval to  market the product.
Failure to  comply with  applicable FDA  and other  regulatory requirements  can
result  in  sanctions being  imposed  on the  Company  and any  of  its contract
manufacturers or distributors. Typical sanctions include warning letters, fines,
product recalls  or seizures,  injunctions, refusals  to permit  products to  be
imported into or exported out of the United States, refusals of the FDA to grant
premarket  approval of drugs  or to allow  the Company to  enter into government
supply contracts, withdrawals of previously approved marketing applications  and
criminal prosecution.
 
                                       37
<PAGE>
    The  activities required before a pharmaceutical  product may be marketed in
the U.S. primarily  begin with  preclinical testing.  Preclinical tests  include
laboratory  evaluation  of product  chemistry and  other  end points  and animal
studies  to  assess  the  potential  safety  and  efficacy  of  the  product  as
formulated.  Many preclinical studies are regulated by the FDA under a series of
regulations called  the current  Good  Laboratory Practice  (cGLP)  regulations.
Violations  of these regulations can, in some cases, lead to invalidation of the
studies, requiring such studies to be replicated.
 
    The entire  body of  preclinical development  work necessary  to  administer
investigational  drugs  to  volunteers  or  patients  is  summarized  in  an IND
submission to the FDA.  FDA regulations provide that  human clinical trials  may
begin  30 days following  the submission and  receipt of an  IND, unless the FDA
advises  otherwise  or   requests  additional   information,  clarification   or
additional  time to review  the IND submission.  There is no  assurance that the
submission of  an IND  will  eventually allow  a  company to  commence  clinical
trials.  Once trials have commenced, the FDA  may stop the trials, or particular
types of trials, by placing a "clinical hold" on such trials because of concerns
about, for example, the safety  of the product being  tested or the adequacy  of
the  trial design. Such holds can cause  substantial delay and in some cases may
require abandonment of a product.
 
    The regulatory process required to be completed by the FDA before a new drug
delivery system may be  marketed in the United  States depends significantly  on
whether  the  drug (which  will  be delivered  by  the drug  delivery  system in
question) has existing approval for use and in what dosage forms. If the drug is
a new chemical entity that has not been approved, then the process includes  (i)
preclinical laboratory and animal tests, (ii) an IND application that has become
effective, (iii) adequate and well-controlled human clinical trials to establish
the  safety and  efficacy of the  drug in  its intended indication  and (iv) FDA
approval of an NDA. If the drug has been previously approved, then the  approval
process is similar, except that certain toxicity tests normally required for the
IND  may  not  be necessary.  Even  with previously  approved  drugs, additional
toxicity testing  may  be  required  when the  delivery  form  is  substantially
changed.  Approval of a drug in a  new delivery system may require demonstration
of bioequivalence  or  clinical  studies to  demonstrate  safety  and  efficacy.
Because  certain of the  Company's drug delivery  mechanisms, by design, produce
high drug concentrations at the surface of the oral mucosa or skin, new toxicity
tests at this site may need to be performed.
 
    Clinical  testing  involves  the  administration  of  the  drug  to  healthy
volunteers  or  to  patients  under the  supervision  of  a  qualified principal
investigator, usually a  physician pursuant  to an FDA  reviewed protocol.  Each
clinical  study  is conducted  under the  auspices of  independent Institutional
Review Boards (IRBs) at the institutions  at which the study will be  conducted.
An  IRB will consider, among other things,  ethical factors, the safety of human
subjects and the possible  liability of the  institution. Human clinical  trials
are  typically conducted in three sequential phases, but the phases may overlap.
Phase I trials consist of testing the  product in a small number of patients  or
normal  volunteers, primarily  for safety,  in one or  more dosages,  as well as
characterization of a drug's pharmacokinetic and/or pharmacodynamic profile.  In
Phase  II, in addition to safety, the efficacy  of the product is evaluated in a
patient population. Phase  III trials typically  involve additional testing  for
safety  and  clinical  efficacy  and an  expanded  population  at geographically
dispersed test  sites.  A  clinical  plan, or  "protocol,"  accompanied  by  the
approval  of the IRB, must be submitted to  the FDA prior to the commencement of
each clinical trial. All patients involved  in the clinical trials must  provide
informed  consent prior  to their  participation. The  FDA has  the authority to
order the temporary or permanent discontinuation of a clinical trial.
 
    A company seeking FDA approval of a  drug must file an application with  the
FDA  pursuant to the FDC Act, as amended in 1984 by the DPCPTRA. The FDC Act, as
amended, provides for several types of applications, including an NDA, which may
be filed under either Section 505(b)(1) or Section 505(b)(2) of the Act, and  an
ANDA under Section 505(j) of the FDC Act. The type of application required to be
filed  depends upon a variety  of factors, including the  nature of the drug and
the extent and availability of scientific data supporting the application.
 
    A 505(b)(2) NDA is an NDA submitted under section 505(b) of the FDC Act  for
a drug for which the investigations described in section 505(b)(1)(A) of the FDC
Act  (full reports of safety and effectiveness) and relied upon by the applicant
for approval of the application were not  conducted by or for the applicant  and
 
                                       38
<PAGE>
are not investigations for which the applicant has obtained a right of reference
or  use from  the person by  or for  whom the investigations  were conducted. In
contrast, an ANDA may not contain human clinical data other than bioavailability
studies. Under the DPCPTRA,  the FDA may  not approve any  version of a  pioneer
drug  for marketing which is submitted to FDA  either in the form of a 505(b)(2)
NDA or an ANDA until all relevant patents for the pioneer drug have expired,  or
until  the patent owner is notified of  the application and given an opportunity
to litigate any patent  related disputes. The patent  holder can bring a  patent
suit  against the ANDA or  505(b)(2) NDA applicant. If  such a lawsuit is filed,
the DPCPTRA mandates an automatic stay of approval of the ANDA or 505(b)(2)  NDA
application  for up to 30 months (subject  to extension), unless a court of last
appeal has ruled in  favor of the  ANDA or 505(b)(2)  NDA applicant. A  petition
submitted  by  Pfizer in  1993  to the  FDA sought  to  prohibit reliance  by an
applicant under a  505(b)(2) NDA on  safety and  other data in  an approved  NDA
file.  The FDA recently denied the petition  but did not decide the legal merits
of the issues presented. Accordingly, any future FDA decision in favor of  legal
arguments  similar  to those  in the  denied petition  could have  a significant
adverse effect  on  the  FDA's  approval of  505(b)(2)  NDAs  because  505(b)(2)
applicants  would  have to  obtain required  data on  the original  pioneer drug
formulation that otherwise meets  the data definition in  505(b)(2) or that  the
applicant  conducts itself. This could delay  submission and/or approval of such
an application.
 
    The DPCPTRA permits the FDA to approve for marketing a generic drug (i.e., a
duplicated or related  version of an  approved pioneer new  drug) that has  been
shown  to be  as safe  and effective as  a pioneer  new drug  whose patents have
expired,  but  without  the   submission  of  "full   reports"  of  safety   and
effectiveness.  These provisions do not apply to insulin or biological products.
A sponsor may seek to obtain FDA  approval through the submission of an ANDA  if
the  drug product is: (1) the same as  an approved pioneer new drug product with
respect to active ingredient(s), route of administration, dosage form,  strength
and conditions of use recommended in the labeling; or (2) a product with certain
changes  from an approved  product (i.e., a combination  drug with one different
active ingredient or a product with a different route of administration,  dosage
form  or  strength) if  the FDA  has  approved a  petition from  the prospective
applicant.  Generally,  a  sponsor  of   an  ANDA  need  not  conduct   clinical
investigations  of safety and  effectiveness other than  to demonstrate that its
product is bioequivalent to the pioneer new drug product. By law, the FDA cannot
approve an  ANDA  unless  it  finds  that  the  generic  drug  product  is  both
bioequivalent  and therapeutically equivalent to  the pioneer drug product. Some
states, however, make  their own bioequivalency  determinations for purposes  of
listing  the generic drug on the state pharmacy formulary, which is necessary to
allow the generic drug to be substituted for the pioneer drug.
 
    If the FDA does ultimately approve an NDA or 505(b)(2) NDA for a product, it
may require, among  other things, postmarketing  testing, including  potentially
expensive  Phase  IV  studies,  and  surveillance  to  monitor  the  safety  and
effectiveness of the drug. In addition, the FDA may in some circumstances impose
restrictions on the  use of  the drug  that may  be difficult  and expensive  to
administer.  Product approvals  may be  withdrawn if  compliance with regulatory
requirements are not maintained or if  problems occur after the product  reaches
the  market. After a  product is approved for  a given indication  in an NDA (or
PLA/ELA), subsequent  new  indications  or  dosages for  the  same  product  are
reviewed  by FDA via the filing and  upon approval of a supplemental application
("sNDA"). The  appropriate sNDA  is much  more focused  than the  NDA and  deals
primarily with safety and efficacy data related to the new indication or dosage,
and  labeling information  for the sNDA  indication or dosage.  Finally, the FDA
requires reporting of certain information  that becomes known to a  manufacturer
of an approved drug.
 
    Biologics,  such as  the Company's  BChE product,  are licensed  pursuant to
Section 351 of the Public Health  Service Act, rather than approved pursuant  to
an  NDA, 505(b)(2) NDA or ANDA under the FDC Act, as amended by the DPCPTRA. FDA
approval of  both a  product license  application ("PLA")  and an  establishment
license  application  ("ELA")  for  the  particular  product  and  the  facility
manufacturing the  product, respectively,  are  required. The  requirements  for
approval  of a PLA/ELA  or supplemental PLA  for new dosages  or indications are
comparable to the  requirements for  approval of an  NDA. However,  there is  no
procedure  comparable to an ANDA for the  approval of generic biologics based on
bioquivalence to an approved pioneer biologic.
 
                                       39
<PAGE>
    Under the Orphan Drug Act,  the FDA may designate  a product or products  as
having  Orphan Drug status  to treat a  "rare disease or  condition," which is a
disease or condition that affects  populations of less than 200,000  individuals
in  the United States, or, if victims of a disease number more than 200,000, the
sponsor establishes that it does not realistically anticipate its product  sales
will be sufficient to recover its costs. If a product is designated as an Orphan
Drug,  then the sponsor  is entitled to receive  certain incentives to undertake
the development and marketing of the product, including high-priority FDA review
of an NDA (or PLA/ELA)  if the indication is  for a serious or  life-threatening
disease.  In addition, the sponsor that obtains the first marketing approval for
a designated Orphan Drug for a given indication is eligible to receive marketing
exclusivity for a period of seven  years. There may be multiple designations  of
Orphan Drug status for a given drug and for different indications. However, only
the  sponsor of  the first  approved NDA  (or PLA/  ELA) for  the same  drug (as
defined by the FDA)  for its use  in treating a given  rare disease may  receive
marketing  exclusivity for such  use. Similar products  considered the same drug
will be blocked from the market for  seven years from the approval of the  first
Orphan  Drug  for  that  indication. Even  if  a  sponsor of  a  product  for an
indication for use with an  Orphan Drug designation is  the first to obtain  FDA
approval  of  an  NDA  (or  PLA)  for  that  designation  and  obtains marketing
exclusivity, another  sponsor's application  for the  same drug  product may  be
approved  by the FDA during the period  of exclusivity if the FDA concludes that
the second drug product is  clinically superior or if  the first sponsor is  not
able to supply adequate quantities of the drug product.
 
    Although  it may be  advantageous to obtain Orphan  Drug status for eligible
products, there can be no assurance that the precise scope of protection that is
currently afforded by Orphan Drug status will be available in the future or that
the current  level of  exclusivity will  remain in  effect. The  Company's  BChE
Injectable  product has been designated an Orphan Drug for both cocaine overdose
and post-surgical apnea  indications by  the FDA  and, under  current laws,  the
Company  is  eligible to  receive  seven years  of  market exclusivity  for each
indication if  it  is  the  first  sponsor to  receive  FDA  approval  for  such
indications.  Such designation,  however, does not  assure that the  FDA has not
granted Orphan Drug designation to  similar products under development nor  does
it assure that it will receive or maintain marketing exclusivity nor that it may
not  be  blocked from  the market  by  a competitor's  product. The  Company has
granted  Rhone-Poulenc  Rorer  an   exclusive  worldwide  license  to   develop,
manufacture  and market BChE  Injectable, and its  subsidiary Armour is pursuing
the clinical investigation necessary to obtain the required safety and  efficacy
data  to support the  filing of a PLA  for this product for  the two Orphan Drug
indications. Only  if Rhone-Poulenc  Rorer successfully  completes the  required
clinical investigations and is the first sponsor to obtain FDA approval of a PLA
for  the  two Orphan  Drug indications  will  it be  eligible to  receive market
exclusivity. There is no  assurance, however, that  Rhone-Poulenc Rorer will  be
the  first sponsor  to obtain FDA  approval to  market BChE for  either of these
indications for  use or  obtain a  period  of market  exclusivity. The  FDA  may
approve  a second application  to market a  drug for the  same indication if the
developer establishes that its drug is a clinically superior product or not  the
same  drug as  defined by  FDA regulations.  If FDA  should approve  BChE for an
indication broader than the  Orphan Drug designation, the  product might not  be
entitled  to exclusive marketing  rights. The failure  of Rhone-Poulenc Rorer to
obtain such marketing exclusivity could have an adverse affect on  Rhone-Poulenc
Rorer's ability to market the BChE Injectable product.
 
    Manufacture  of a biologic  product, such as  the Company's BChE Injectable,
must be in a facility covered  by an FDA-approved ELA. Manufacture, holding  and
distribution  of both biologic and non-biologic drugs must be in compliance with
cGMP. Manufacturers must continue to expend  time, money and effort in the  area
of  production and quality control to ensure full technical and other compliance
with those requirements. The  labeling, advertising and promotion  of a drug  or
biologic product must be in compliance with FDA regulatory requirements. Failure
to  comply with applicable requirements relating to manufacture, distribution or
promotion can lead to  FDA demands that  manufacturing, production and  shipment
cease  until  changes are  made and  approved by  the FDA.  In some  cases, such
failures can lead to product recalls, or to enforcement actions that can include
seizures, injunctions and criminal prosecution or FDA withdrawal of approval  to
market  the  product.  If  the  Company  is  required  to  improve manufacturing
operations prior to receiving  FDA approval of  the product, marketing  approval
could be substantially delayed.
 
                                       40
<PAGE>
    To date, the Company has filed INDs and is conducting clinical trials on two
of  its products,  and an  additional five  of the  Company's product candidates
could be ready to enter either Phase  I or Phase III clinical trials during  the
next  12 months. The Company's NDA for Carbatrol was accepted for filing on June
1, 1996 and  the Company has  completed the  clinical portion of  the Phase  III
study  on its Selegiline SR product for the cocaine craving indication (although
the results of  such study  are not yet  available). The  Company has  completed
Phase I clinical trials on its Selegiline SR product for the Parkinson's Disease
indication  and intends to commence Phase  III clinical studies on Selegiline SR
for the foregoing  indication upon  obtaining a collaborative  partner. See  "--
Products  In Development." There  can be no  assurance that any  required FDA or
other governmental  approval  will  be  granted or,  if  granted,  will  not  be
withdrawn.  Governmental  regulation  may  prevent  or  substantially  delay the
marketing of the Company's proposed products and cause the Company to  undertake
costly  procedures.  A  number of  other  factors  related to  the  FDA approval
process, however,  may  delay or  preclude  approval  of any  of  the  Company's
products.  In addition, the extent of potentially adverse government regulations
that might  arise from  future administrative  action or  legislation cannot  be
predicted.  Failure to obtain FDA approval to market Carbatrol, Selegiline SR or
any of its other products under development could have a material adverse effect
on the Company.
 
    The Company has submitted or intends  to submit 505(b)(2) NDAs or ANDAs  for
Carbatrol,  Selegiline SR and certain of  its other non-biological drug products
under development. There can be no assurance, however, that the FDA would permit
the Company  to  obtain  marketing  approval  of  these  products  through  such
submissions.  Nor can  there be any  assurance that the  Company, if challenged,
would be able to demonstrate that any applicable patent relating to the approved
new drug  product will  not be  infringed or  is invalid  or be  able to  defend
successfully  against any  litigation brought by  the patent  holder. Failure to
obtain marketing approval for Carbatrol, Selegiline SR or any other drug product
for which the Company seeks to obtain approval through the submission of an ANDA
or 505(b)(2) NDA on  a timely basis,  if at all, could  have a material  adverse
effect on the Company.
 
    The DPCPTRA grants marketing exclusivity to certain NDAs and NDA supplements
submitted  to  the FDA  after  1984. To  qualify  for three  years  of marketing
exclusivity for an  NDA supplement, the  pioneer must submit  an NDA  supplement
that contains reports of new clinical investigations (other than bioavailability
studies)  that are  "essential to approval"  and "conducted or  sponsored by the
applicant." The  three-year exclusivity  will cover  "a change  approved in  the
supplement."  While the  FDA has  declined to  formally define  what changes are
covered by  this language,  it  could include  a  new indication,  dosage  form,
strength,  route  of administration  or dosing  regimen.  Therefore, if  the FDA
approves a sponsor's NDA  supplement and such  NDA supplement contains  clinical
studies  (other than  bioavailability studies)  that are  new, are  essential to
approval, and  are conducted  or sponsored  by the  applicant, the  FDA may  not
approve  a  505(b)(2)  NDA or  an  ANDA for  the  same "change  approved  in the
supplement" for  three years  from the  date of  approval of  the pioneer's  NDA
supplement.  Thus, 505(b)(2)  NDAs or  ANDAs submitted  after the  sponsor's NDA
supplement has been  approved may  not be  approved or  the product  may not  be
marketed in the United States until the end of that three-year period.
 
    Until FDA approval of an NDA, FDA filings are not public and it is typically
not  known what, if  any, clinical studies  are submitted by  a sponsor. In this
connection, however, the Company received information pursuant to a FOIA request
that CIBA-Geigy has filed, and obtained approval on March 25, 1996, for, an  NDA
supplement  for an extended-release formulation of carbamazepine under its brand
name  Tegretol.  The  FOIA  documentation  further  discloses  that   CIBA-Geigy
requested that the FDA grant it three years market exclusivity commencing on the
date  of  approval  of the  Tegretol  NDA  supplement and  that  the  FDA denied
CIBA-Geigy's request for such exclusivity.
 
    In order to export an unapproved drug  or biologic for commercial sale in  a
foreign  country,  a  company  must  comply  with  the  FDA  Export  Reform  and
Enhancement Act of 1996  (the "EREA"). The EREA  permits a product not  approved
for  sale in the United States to be exported to any country, without FDA export
approval, if the following two requirements are met: first, the product must  be
lawful  in  the  country of  destination;  second,  the product  must  have been
approved   for    marketing    in    one    of    the    following    countries:
 
                                       41
<PAGE>
Australia,  Canada, Israel,  Japan, New  Zealand, Switzerland,  South Africa and
countries in the European  Union (EU) or European  economic area. The EREA  also
provides  other  methods  which  require FDA  authorization  for  the  export of
unapproved products.
 
    In recent years, there have been numerous proposals to reform the healthcare
system in the United States, including currently pending legislation relating to
Medicare and Medicaid. Some of these proposals have included measures that would
limit or eliminate  payments for  certain medical procedures  and treatments  or
subject  the  pricing of  pharmaceuticals  to government  control.  In addition,
significant uncertainty exists as to the reimbursement status of newly  approved
healthcare  products.  The  Company's  ability  to  commercialize  its  products
successfully may also depend  in part on the  extent to which reimbursement  for
the  cost  of  such  products  and  related  treatment  will  be  available from
government health administration authorities, private health insurers and  other
organizations. Such third-party payors are increasingly challenging the price of
medical  products and services. It is  uncertain what legislative proposals will
be adopted or what actions federal, state or private payors for healthcare goods
and services may take in response to proposed or actual legislation. The Company
cannot predict the effect health  care reform may have  on its business, and  no
assurance  can be given that  any such reforms will  not have a material adverse
effect on the company.  Significant uncertainty exists  as to the  reimbursement
status  of newly approved  health care products,  and there can  be no assurance
that adequate third-party coverage  will be available to  enable the Company  to
maintain  price  levels  sufficient to  realize  an appropriate  return  on this
investment in product development.
 
    The Company is  also subject to  regulation by the  Occupational Safety  and
Health Administration ("OSHA"), the Environmental Protection Agency ("EPA"), the
Drug  Enforcement  Administration  ("DEA")  and to  regulation  under  the Toxic
Substances Control Act,  the Resource  Conservation and Recovery  Act and  other
regulatory statutes, and may in the future be subject to other federal, state or
local  regulations. Either or both of OSHA or the EPA may promulgate regulations
that may affect the Company's research and development programs.  Establishments
handling  controlled  substances,  such  as alprazolam  and  lorazepam,  must be
licensed and are inspected by the DEA. The Company is unable to predict  whether
any  agency will adopt any regulation which would have a material adverse effect
on the Company's operations.
 
    To market its products abroad, the  Company is also subject to numerous  and
varying   foreign  regulatory   requirements,  implemented   by  foreign  health
authorities, governing,  among other  things, the  design and  conduct of  human
clinical  trials,  pricing  regulations and  obtaining  marketing  approval. The
approval procedure varies  among countries and  can involve additional  testing,
and  the time  required to obtain  approval may  be longer or  shorter from that
required to obtain FDA approval, and approval or other product requirements  may
differ.  At  present,  foreign marketing  authorizations  are applied  for  at a
national level,  although within  the EU,  certain registration  procedures  are
available  to companies wishing to  market a product in  more than one EU member
country. If  a  regulatory authority  is  satisfied that  adequate  evidence  of
safety,  quality  and efficacy  has been  presented, marketing  authorization is
almost always granted. The foreign regulatory approval includes all of the risks
associated with obtaining FDA approval set forth above. Approval by the FDA does
not ensure approval by other countries.
 
FACILITIES
 
    The Company is  located in  a 44,500  square foot  facility containing  both
office  and laboratory space  in Rockville, Maryland.  The facility is subleased
from Corning  Clinical Laboratories,  Inc. The  sublease has  a five-year  term,
beginning  May 1, 1995,  with the first  and second month  rent abated, and nine
months of additional free rent. The  initial rental rate is $601,000 per  annum,
increasing by 3% per annum in each year of the sublease term.
 
HUMAN RESOURCES
 
    As of July 1, 1996, the Company had 55 employees, 45 of whom were engaged in
research and development activities. The Company's employees are not governed by
any   collective  bargaining  agreement  and   the  Company  believes  that  its
relationship with its employees is good.
 
LEGAL PROCEEDINGS
 
    The Company is not a party to any material legal proceedings.
 
                                       42
<PAGE>
                                   MANAGEMENT
 
EXECUTIVE OFFICERS AND DIRECTORS
 
    The  executive officers and directors  of the Company, and  their ages as of
July 1, 1996, are as follows:
 
<TABLE>
<CAPTION>
                 NAME                        AGE                           POSITION
- ---------------------------------------      ---      ---------------------------------------------------
<S>                                      <C>          <C>
James D. Isbister (1)                            59   Chief Executive Officer and Chairman of the Board
                                                       of Directors
Robert S. Cohen                                  53   President and Chief Operating Officer
Krystyna Belendiuk, Ph.D.                        45   Senior Vice President -- Business Development,
                                                       Director and Secretary
James D. Russo                                   49   Senior Vice President -- Chief Financial Officer
                                                       and Treasurer
Edward M. Rudnic, Ph.D.                          40   Senior Vice President -- Development and Technical
                                                       Operations
James H. Cavanaugh, Ph.D. (1)(3)                 59   Director
Max Link, Ph.D. (2)(3)                           55   Director
Lawrence C. Hoff (2)                             67   Director
</TABLE>
 
- --------------
(1) Member of Executive Committee
 
(2) Member of Audit Committee
 
(3) Member of Compensation Committee
 
    The Board of  Directors currently  consists of five  members. All  directors
hold  office  until the  next  annual meeting  of  stockholders and  until their
successors are  duly  elected and  qualified.  Officers are  elected  to  serve,
subject  to the discretion of the Board of Directors, until their successors are
appointed.
 
    JAMES D. ISBISTER has been President, Chief Executive Officer and a Director
of the Company since January 1990 and was appointed to serve as the Chairman  of
the  Board of Directors  in October 1995.  Effective July 1,  1996, Mr. Isbister
resigned as President of the Company with the appointment of Robert S. Cohen  as
President,  but continues to serve as Chairman  of the Board and Chief Executive
Officer. Mr. Isbister plans to retire  as Chief Executive Officer no later  than
January  1, 1997.  From 1986  until January 1989,  Mr. Isbister  was Senior Vice
President of Consolidated HealthCare and served as President of its  subsidiary,
Combined  Technologies, Inc. Mr. Isbister served as Senior Vice President of the
National Blue Cross and Blue Shield Association (the "Association") from 1980 to
1986 and as a consultant to the  Association from January 1989 to January  1990.
From 1978 to 1980, Mr. Isbister was the Associate Director for Management of the
U.S.  International Communication Agency. Mr. Isbister served as Deputy Director
of the National Institute of  Mental Health from 1970 to  1974 and as the  first
Director  of the U.S. Alcohol, Drug Abuse, and Mental Health Administration from
1974 to 1977.
 
    ROBERT S. COHEN joined the Company as President and Chief Operating  Officer
effective  July 1, 1996. Prior  to joining the Company,  Mr. Cohen had extensive
experience as a pharmaceutical company executive. From September 1995 until June
1996, Mr.  Cohen served  as President  and Chief  Operating Officer  of  Trophix
Pharmaceuticals,  Inc. ("Trophix"),  where he remains  a member of  the Board of
Directors. From June 1993 until August  1995, Mr. Cohen served as President  and
Chief  Executive Officer of  Gynopharma, Inc. From  June 1980 to  June 1993, Mr.
Cohen was employed  by Berlex  Laboratories, Inc.,  a division  of Schering  AG,
serving  as Chief Operating Officer commencing  in 1989. Mr. Cohen will continue
to assist Trophix  with some  projects through 1996  on a  part-time basis.  Mr.
Cohen  has a B.S. and M.S. in Pharmacy from the Brooklyn College of Pharmacy and
is a registered pharmacist.
 
    KRYSTYNA BELENDIUK has been Senior Vice President for Business  Development,
a  Director and Secretary  since April 1991  and served as  Treasurer from April
1991 to  May  1994.  Prior to  joining  the  Company, Dr.  Belendiuk  served  as
Executive  Director, Corporate Planning and Control,  from October 1990 to April
1991, and  as  Director, Corporate  Planning  and  Analysis from  June  1988  to
September  1990,  at CIBA-Geigy  Corp.  From 1984  to  May 1988,  she  served as
Director   and    then    Executive    Director    of    Portfolio    Management
 
                                       43
<PAGE>
with   the  Pharmaceuticals  Division  of  CIBA-Geigy  Corp.  Prior  to  joining
CIBA-Geigy Corp.,  Dr.  Belendiuk  served  as a  marketing  manager  for  Sandoz
Pharmaceuticals  Corp. In addition to a doctorate in Biopsychology, she holds an
M.B.A. in Finance and Marketing, both from the University of Chicago.
 
    JAMES D. RUSSO has been Senior  Vice President, Chief Financial Officer  and
Treasurer  since May, 1994.  Prior to joining  the Company, Mr.  Russo served as
Senior Vice President, Chief Financial Officer and Treasurer of Versar, Inc.  an
environmental  consulting firm from  1992 to 1994.  Mr. Russo was  a Senior Vice
President  and  Chief   Financial  Officer  of   ICF  International,  Inc.,   an
international  environmental engineering  firm and  health care  consulting firm
("ICF") from 1986 to 1992. From 1986 to 1988 he also served as Treasurer of ICF.
From 1977 to 1986, Mr. Russo was Vice President of Finance, Treasurer and served
on the Board  of Directors of  PRC Engineering, Inc.,  a subsidiary of  Planning
Research Corporation, where he managed the international financial operations of
the consulting engineering firm. Mr. Russo is a Certified Public Accountant.
 
    EDWARD  M. RUDNIC has been Senior  Vice President, Development and Technical
Operations, since February 1996. From April  1991 to February 1996, he was  Vice
President  for  Pharmaceutical Research  and  Development. Dr.  Rudnic  has over
fifteen  years  of   industry  experience   in  the   design,  formulation   and
commercialization  of advanced drug delivery systems. From October 1990 to April
1991, Dr. Rudnic was an independent  consultant. From 1987 to October 1990,  Dr.
Rudnic served as Director of Formulation Development with Schering-Plough Corp.,
and  from 1985 until  1987, as a Manager  of Pharmaceutical Process Development.
From 1982 until 1985, Dr. Rudnic was a Research Investigator at E. R. Squibb and
Sons, developing oral  controlled-release dosage forms  and novel drug  delivery
concepts.  Dr. Rudnic  has a B.S.  in Pharmacy,  an M.S. in  Pharmaceutics and a
doctorate in Pharmaceutical Sciences  from the University  of Rhode Island.  Dr.
Rudnic is a registered pharmacist.
 
    JAMES  H.  CAVANAUGH has  served  as a  Director  of the  Company  since its
inception. Since 1989, Dr. Cavanaugh has been President of HealthCare Investment
Corporation LLC ("HIC") and is currently a general partner of each of HealthCare
Partners I, L.P. ("HCP I"), HealthCare Partners II, L.P. ("HCP II"),  HealthCare
Partners  III, L.P. ("HCP III") and HealthCare Partners IV, L.P. ("HCP IV"), the
general partners of HealthCare Ventures  I, L.P. ("HCV I"), HealthCare  Ventures
II,  L.P. ("HCV II"),  HealthCare Ventures III, L.P.  ("HCV III") and HealthCare
Ventures IV, L.P.  ("HCV IV"),  respectively. HCV  II, HCV  III and  HCV IV  are
principal  stockholders of the  Company. Prior thereto,  Dr. Cavanaugh served as
President of SmithKline & French Laboratories  -- U.S., Inc. from March 1985  to
February  1989 and as President of SmithKline Clinical Laboratories from 1981 to
1985. In addition to serving on the  Boards of Directors of several health  care
and    biotechnology    companies,   including    MedImmune,    Inc.,   Magainin
Pharmaceuticals, Inc.,  Human  Genome  Sciences,  Inc.  and  Procept,  Inc.  Dr.
Cavanaugh  currently serves on the Executive  Committee of the Board of Trustees
of the National Committee for Quality Health Care (Chairman, 1988), the National
Committee of the  American Refugee  Committee, the  Board of  Councilors of  the
School  of  Pharmacy of  the University  of Southern  California and  as Trustee
Emeritus of the California College of Medicine. Dr. Cavanaugh received his Ph.D.
from the University of Iowa.
 
    MAX LINK has  served as a  Director of  the Company since  January 1995.  In
addition,  Dr. Link has held a number of executive positions with pharmaceutical
and healthcare companies. Most recently, he served as Chief Executive Officer of
Corange Limited,  from May  1993  until June  1994.  Prior to  joining  Corange,
Limited,  Dr. Link  served in  a number  of positions  with Sandoz  Pharma Ltd.,
including Chief Executive  Officer, from  1990 until April  1992, and  Chairman,
from  April  1992 until  May 1993.  Dr. Link  currently serves  on the  board of
directors  of  Alexion  Pharmaceuticals,  Inc.,  Human  Genome  Sciences,  Inc.,
Procept,  Inc. and  Protein Design  Labs, Inc.  Dr. Link  received his  Ph.D. in
Economics from the University of St. Gallen.
 
    LAWRENCE C. HOFF became a Director of the Company in February 1996. In 1990,
Mr. Hoff retired as President and Chief Operating Officer of the Upjohn  Company
("Upjohn").   Mr.  Hoff  joined  Upjohn  in   1950  as  a  pharmaceutical  sales
representative. He  was appointed  Vice  President for  Domestic  Pharmaceutical
Marketing  in 1969. In 1973,  Mr. Hoff was elected to  the Board of Directors of
Upjohn on which he  served as a  director until the  Upjohn Company merged  with
Pharmacia in 1995. In 1974, he became Vice President
 
                                       44
<PAGE>
and  General Manager of  Domestic Pharmaceutical Operations.  From 1974 to 1984,
Mr. Hoff served as Executive Vice President  at Upjohn. Mr. Hoff was elected  to
the  Board of Directors of  the Pharmaceutical Manufacturers Association ("PMA")
in 1984. He was elected Chairman-elect of the PMA in 1986 and Chairman in  1987.
Mr.  Hoff  currently  serves  as  a  director  of  Curative  Technologies, Inc.,
MedImmune, Inc.,  Alpha  Beta  Technologies  and  Pathogenesis,  Inc.  Mr.  Hoff
graduated  from  Stanford  University  and has  received  honorary  degrees from
Massachusetts College of Pharmacy and Allied Health Sciences and from  Kalamazoo
College.
 
    The  Board of Directors established the Audit Committee in October 1995. The
Audit  Committee  is  authorized  to  review  with  the  Company's   independent
accountants,   the  annual  financial   statements  of  the   Company  prior  to
publication; to review the work of, and approve non-audit services performed by,
such independent accountants; and  to make annual  recommendations to the  Board
for  the appointment of independent public accountants for the ensuing year. The
Audit Committee also reviews the  effectiveness of the financial and  accounting
functions, organization, operations and management of the Company.
 
    The  Board of Directors established the  Compensation Committee in May 1991.
The Compensation Committee is authorized to review and recommend to the Board of
Directors the compensation  and benefits of  all officers and  directors of  the
Company  and  to  review general  policy  matters relating  to  compensation and
benefits  of  employees  of  the   Company.  The  Compensation  Committee   also
administers  the issuance of stock options  to the Company's officers, employees
and consultants pursuant to the Company's 1991 Stock Option Plan.
 
    Directors, with the  exception of  Dr. Link and  Mr. Hoff,  receive no  cash
compensation  for their  services as directors  but are  reimbursed for expenses
actually incurred  in  connection  with  attending  meetings  of  the  Board  of
Directors.  Dr. Link receives $20,000 per annum  and has been granted options to
purchase 7,822 shares of Common  Stock at an exercise  price of $4.50 per  share
and  2,224 shares of Common  Stock at an exercise price  of the greater of $4.50
per share  or  85% of  the  initial public  offering  price per  share  in  this
offering.  Mr.  Hoff receives  $15,000 per  annum, plus  expenses, and  has been
granted options to purchase 6,850 shares of Common Stock at an exercise price of
the greater of $4.50 per share or  85% of the initial public offering price  per
share  in this  offering. In  addition, directors who  are not  employees of the
Company are entitled  to receive automatic  stock option grants.  See "--  Stock
Options."
 
    The   Company's  Restated  Certificate  of  Incorporation  includes  certain
provisions permitted pursuant to Delaware law whereby officers and directors  of
the  Company are to  be indemnified by the  Company against certain liabilities.
The Company's Restated Certificate of Incorporation also limits, to the  fullest
extent  permitted by Delaware  law, a director's  liability for monetary damages
for breach of fiduciary duty,  including gross negligence, except liability  for
(i) breach of the director's duty of loyalty, (ii) acts or omissions not in good
faith or which involve intentional misconduct or a knowing violation of the law,
(iii)  the  unlawful  payment  of  a  dividend  or  unlawful  stock  purchase or
redemption and (iv) any transaction from which the director derives an  improper
personal  benefit. Delaware law does not eliminate a director's duty of care and
this provision has no effect on  the availability of equitable remedies such  as
an  injunction or rescission based upon a director's breach of the duty of care.
In addition, the Company has obtained an insurance policy providing coverage for
certain liabilities of its officers and directors.
 
SCIENTIFIC ADVISORY BOARD
 
    The  Company's  Scientific  Advisory   Board  currently  consists  of   four
individuals  who  have  extensive  experience  in  the  fields  of pharmacology,
chemistry, neurosciences, enzymology  and molecular genetics.  At the  Company's
request,  the  scientific advisors  review and  evaluate the  Company's research
programs and advise the Company about technical matters in the scientific fields
in which  the  Company is  involved.  The Company's  Scientific  Advisory  Board
generally meets as a group at least three times a year to review and discuss the
Company's  progress in research and development. In addition, certain members of
the Scientific Advisory Board meet informally in smaller groups or  individually
with Company scientists on a more frequent basis.
 
                                       45
<PAGE>
    The  following  table  sets forth  the  name  and current  position  of each
scientific advisor:
 
<TABLE>
<CAPTION>
            NAME                                             POSITION
- ----------------------------  -----------------------------------------------------------------------
<S>                           <C>
Floyd Bloom, M.D.             Chairman of the Scientific Advisory Board. Chairman, Department of
                               Neuropharmacology, The Scripps Research Institute
Roscoe Brady, M.D.            Chief, Developmental and Metabolic Neurology Branch, National
                               Institutes of Health
John J. Burns, Ph.D.          Adjunct Member, Roche Institute of Molecular Biology and Adjunct
                               Professor, The Rockefeller University
Paul Greengard, Ph.D.         Vincent Astor Professor, Laboratory of Molecular and Cellular
                               NeuroScience, The Rockefeller University
</TABLE>
 
    The Company has entered into consulting  agreements with each member of  the
Scientific  Advisory Board. The Consulting Agreements  are for varying terms and
provide for each of the members to serve on the Scientific Advisory Board of the
Company and/or to  render advice to  the Company  in the area  of the  Company's
business and such member's expertise for specified annual compensation for their
services.  The Company's scientific advisors are  employed by other entities and
some have consulting agreements  with entities other than  the Company, some  of
which  may in the future  compete with the Company.  The scientific advisors are
expected to devote only a small portion of their time to the Company and are not
expected to participate actively  in the day-to-day  operations of the  Company.
Certain  of the institutions  with which the  scientific advisors are affiliated
may adopt new regulations or policies  that limit the ability of the  scientific
advisors to consult with the Company.
 
    It is possible that any inventions or processes discovered by the scientific
advisors will remain the property of such persons or of such persons' employers.
In  addition, the institutions with which the scientific advisors are affiliated
may make  available the  research  services of  their personnel,  including  the
scientific  advisors,  to  competitors  of  the  Company  pursuant  to sponsored
research agreements.
 
                                       46
<PAGE>
EXECUTIVE COMPENSATION
 
    The  following  summary   compensation  table  sets   forth  the   aggregate
compensation  paid or accrued by the Company  to the Chief Executive Officer and
to the four  most highly  compensated executive  officers other  than the  Chief
Executive  Officer whose  annual compensation  exceeded $100,000  for the fiscal
year ended December 31, 1995 (collectively, the "named executive officers")  for
services  rendered during  the fiscal  years ended  December 31,  1995, 1994 and
1993:
 
                           SUMMARY COMPENSATION TABLE
 
<TABLE>
<CAPTION>
                                                                                                           LONG-TERM
                                                                                                         COMPENSATION
                                                                                                            AWARDS
                                                                                                         -------------
                                                                     ANNUAL COMPENSATION                   NUMBER OF
                                                      -------------------------------------------------   SECURITIES
                                                                                          OTHER ANNUAL    UNDERLYING
NAME AND PRINCIPAL POSITION                             YEAR       SALARY     BONUS (1)   COMPENSATION      OPTIONS
- ----------------------------------------------------  ---------  ----------  -----------  -------------  -------------
<S>                                                   <C>        <C>         <C>          <C>            <C>
James D. Isbister (2)...............................       1995  $  225,239   $  75,000    $   3,516(3)       82,472
Chairman of the Board                                      1994     214,513      75,000        3,373(3)            0
 President and Chief                                       1993     204,298      50,000        1,174(3)       85,696
 Executive Officer
Dr. George W. Belendiuk (4).........................       1995  $  176,248   $  41,964    $  40,403(5)       37,201
Senior Vice President --                                   1994     167,885      31,972       33,805(5)        4,167
 Research & Development                                    1993     159,862      30,450            0          43,334
Dr. Krystyna Belendiuk..............................       1995  $  149,826   $  28,538            0          37,201
Senior Vice President --                                   1994     142,691      27,179            0           4,167
 Business Development                                      1993     135,896      18,598            0          43,334
Dr. Edward M. Rudnic................................       1995  $  131,846   $  25,114            0          23,021
Senior Vice President --                                   1994     125,568      23,918            0           2,500
 Pharmaceutical Operations                                 1993     119,589      16,366            0          19,000
James D. Russo......................................       1995  $  138,961   $  30,000            0          18,113
Senior Vice President --                                   1994      79,219           0            0          16,667
 Chief Financial Officer (5)                               1993           0           0            0               0
</TABLE>
 
- --------------
(1) Bonus in this chart represents the  amount actually paid to the employee  in
    the year indicated, but earned in the preceding year.
 
(2) Effective  July 1, 1996,  Mr. Isbister resigned as  President of the Company
    with the appointment of Robert S. Cohen as President, but continues to serve
    as Chairman of the Board and Chief Executive Officer.
 
(3) Compensation adjustment related to value of automobile provided to employee.
 
(4) Dr. George Belendiuk died on April 20, 1996.
 
(5) Relocation expense reimbursement.
 
(6) Mr. Russo's employment with the Company commenced in May 1994.
 
EMPLOYMENT AGREEMENTS
 
    The Company  has  entered  into  employment agreements  with  each  of  Drs.
Krystyna  Belendiuk and  Edward Rudnic  and Mr.  James Russo,  each of  which is
effective July  1, 1996,  which  provide for  current  annual base  salaries  of
$157,317,   $153,000  and  $153,000,  respectively.  The  agreements  renew  for
successive one year  periods unless terminated  earlier by either  party on  180
days'  written notice. In  the event any of  the officers' employment agreements
are terminated  without cause,  such officer  will be  entitled to  receive  the
unpaid portion of the base salary payable through the date of termination of the
agreement,  plus a payment equal to the lesser  of (i) one year's base salary or
(ii) nine  months'  base salary  or  the base  salary  for the  remaining  term,
whichever  is greater, payable in equal  monthly installments for the applicable
period. The
 
                                       47
<PAGE>
agreements also provide for the  vesting and acceleration of the  exercisability
of unvested stock options if the employee is terminated or his or her duties are
substantially reduced after certain corporate transactions involving a change in
control of the Company.
 
    In  May 1996, the Company paid $92,530 to the estate of Dr. George Belendiuk
pursuant to the terms  of his employment agreement  and awarded Dr. Belendiuk  a
cash  bonus of $20,000 upon acceptance by  the FDA of the Company's NDA relating
to Carbatrol.  Further, the  Company modified  the terms  of all  stock  options
granted to Dr. Belendiuk to provide that stock options which were exercisable as
of  May 14, 1996  or which will become  exercisable on or  before April 20, 1997
shall remain exercisable by his estate  until twelve months from the closing  of
this offering.
 
    The  Company has entered into a  one-year employment agreement with James D.
Isbister effective  December 12,  1995 providing  for a  base annual  salary  of
$236,500. The agreement contains severance provisions similar to those contained
in  the Company's employment agreements with  Drs. Krystyna Belendiuk and Edward
Rudnic and Mr. James Russo and further provides that Mr. Isbister will have  the
right  to terminate the agreement and  for immediate vesting and acceleration of
the  exercisability  of  unvested  stock  options  in  the  event  of  death  or
disability.  Mr.  Isbister plans  to retire  as Chief  Executive Officer  of the
Company no later than January 1, 1997. It is expected that Robert S. Cohen,  the
Company's  President and  Chief Operating Officer  effective July  1, 1996, will
succeed Mr. Isbister as Chief Executive Officer. The Company has entered into an
Agreement with Mr. Isbister under which he will continue to serve as Chairman of
the Company's Board  of Directors  through December 31,  1998 if  he resigns  as
Chief  Executive Officer on  or before December 31,  1998. Under that Agreement,
Mr.  Isbister  will  receive  $65,000  annually  and  certain  other  employment
benefits.
 
    The  Company entered into  a three-year employment  agreement with Robert S.
Cohen effective July 1, 1996 providing for  Mr. Cohen to serve as President  and
Chief  Operating Officer for a  base annual salary of  $200,000. Mr. Cohen shall
also be eligible to receive an annual bonus of up to 33 1/3% of his base salary.
The agreement further  provides for Mr.  Cohen to be  reimbursed for  relocation
expenses  not to exceed  $100,000 in the  aggregate. The agreement automatically
renews for successive one year periods unless terminated earlier by either party
on 180  days'  prior written  notice  commencing 180  days  prior to  the  third
anniversary  of the effective date of the  agreement. In the event the agreement
is terminated  by the  Company without  cause,  Mr. Cohen  will be  entitled  to
receive  the  unpaid portion  of his  base  salary payable  through the  date of
termination of the  agreement plus  a payment  equal to  the lesser  of (i)  one
year's  base salary payable  in 12 equal  monthly installments or  (ii) the base
salary for  the  then remaining  term  of the  agreement,  payable in  the  same
installments as the base salary under the agreement. The agreement also provides
for the vesting and acceleration of the exercisability of unvested stock options
if Mr. Cohen is terminated or his duties are substantially reduced after certain
corporate  transactions involving a change in  control of the Company. Mr. Cohen
was also  granted  options to  purchase  225,000  shares of  Common  Stock.  See
"--Stock Options."
 
    Each  of  the  named executive  officers  and  Mr. Cohen  have  entered into
confidentiality, patent assignment and non-compete agreements with the Company.
 
STOCK OPTIONS
 
    In July 1991, the Board of Directors  of the Company adopted the 1991  Stock
Option  Plan (the "Stock Option Plan"). Under the Stock Option Plan, as amended,
1,900,000 shares  of  Common  Stock  were reserved  for  issuance  to  officers,
employees,  directors, consultants and advisors of the Company (subject to anti-
dilution and  other  adjustments). As  of  July  1, 1996,  625,151  shares  were
available  for  future  grant and  options  to acquire  1,202,608  shares remain
outstanding under  the Stock  Option Plan,  exercisable at  prices ranging  from
$0.06  to $4.50, except that certain  options to purchase shares are exercisable
at the greater of $4.50 or 85% of the initial public offering price per share in
this offering. The Stock Option Plan  provides for the grant of incentive  stock
options  intended to qualify as  such under Section 422  of the Internal Revenue
Code of  1986,  as amended,  and  nonstatutory stock  options  which do  not  so
qualify.
 
    The  Stock Option  Plan is administered  by the  Compensation Committee (the
"Committee") of the  Board of Directors,  which consists of  Drs. Cavanaugh  and
Link. Effective upon consummation of the
 
                                       48
<PAGE>
offering, option grants to "officers" and "directors," as such terms are defined
for  the purposes of Rule 16b-3  ("Rule 16b-3") promulgated under the Securities
Exchange Act of 1934 (the "Exchange Act"), shall be administered by a  committee
which  consists of "disinterested" directors as  defined in Rule 16b-3, but only
if at least  two directors  meet the  criteria of  "disinterested" directors  as
defined  in Rule 16b-3.  The maximum number  of shares for  which options may be
granted to any participant under the Stock Option Plan during any fiscal year is
250,000 shares. Subject to the limitations  set forth in the Stock Option  Plan,
the  Committee has the authority  to determine to whom  options will be granted,
the term  during  which options  granted  under the  Stock  Option Plan  may  be
exercised,  the exercise price of  options and the rate  at which options may be
exercised and may vest. Nonstatutory stock  options may be granted to  officers,
employees,  consultants and advisors of the Company. Incentive stock options may
be granted only to  employees or officers  of the Company.  The maximum term  of
each  incentive stock option granted  under the Stock Option  Plan is ten years.
The exercise price of  shares of Common Stock  subject to options qualifying  as
incentive stock options may not be less than the fair market value of the Common
Stock  on the date of the grant. The exercise price of incentive options granted
under the Stock Option  Plan to any participant  who owns stock possessing  more
than  10% of the total combined voting power of all classes of outstanding stock
of the Company must be at  least equal to 110% of  the fair market value on  the
date  of grant.  Any incentive stock  options granted to  such participants must
also expire within five  years from the  date of grant.  Under the Stock  Option
Plan,  the exercise price of both incentive stock options and nonstatutory stock
options is payable in  cash or, at  the discretion of  the Committee, in  Common
Stock or a combination of cash and Common Stock.
 
    The  Board may  at any time  modify and amend  the Stock Option  Plan in any
respect, PROVIDED that the  approval of at least  a majority of the  outstanding
shares  of stock of the  Company entitled to vote  is required for any amendment
which (i) changes the class of persons  eligible for the grant of options,  (ii)
increases  the maximum  number of  shares subject  to options  granted under the
Stock Option  Plan  or  (iii)  materially increases  the  benefits  accruing  to
participants  under the Stock Option  Plan, within the meaning  of Rule 16b-3 of
the Exchange Act.  Except with respect  to options then  outstanding, the  Stock
Option  Plan expires on (i) the tenth anniversary of the date on which the Stock
Option Plan is adopted by the Board,  (ii) the tenth anniversary of the date  on
which  the Stock Option Plan is approved  by the stockholders of the Company, or
(iii) the date as of  which the Board, in  its sole discretion, determines  that
the  Stock Option Plan  should terminate, whichever  is the first  to occur. Any
options outstanding as  of the  expiration date of  the Stock  Option Plan  will
remain in effect until they have been exercised or have terminated or expired by
their respective terms.
 
    The  Committee, in its discretion,  may in connection with  the grant of any
option under the Stock Option Plan,  grant to the optionee a stock  appreciation
right (an "SAR"). Such SAR shall be granted by the Committee simultaneously with
the  grant of  the related  option. An exercise  of an  SAR shall  result in the
cancellation of the  option as to  the shares  of Common Stock  with respect  to
which  the optionee  exercises such  SAR. As  soon as  practicable following the
exercise of an  SAR, the Company  shall pay to  the optionee in  cash an  amount
equal  to the excess of the Fair Market Value (determined in accordance with the
provisions of the Stock Option  Plan on the date of  exercise) of the shares  of
Common  Stock with respect to which the option is canceled over the option price
of such shares. An  SAR shall be  exercisable to the same  extent and under  the
same  conditions as, and shall terminate upon the termination of, the underlying
option. An SAR,  however, shall be  exercisable only  at such time  as the  Fair
Market  Value (determined in accordance with  the provisions of the Stock Option
Plan) of the shares  of Common Stock  on the date of  exercise exceeds the  Fair
Market Value of the shares on the date of grant. No SAR shall be exercisable for
cash  during the first year  after the Company becomes  subject to Rule 16b-3 of
the  Exchange  Act.  Neither  options  nor  SARS  are  assignable  or  otherwise
transferable  by  the  optionee  except  by will  or  the  laws  of  descent and
distribution.
 
    The Company may  accelerate the  exercisability of the  options, subject  to
limitation  to the extent necessary to prevent the options from being treated as
a parachute  payment  within  the meaning  of  Section  280G of  the  Code.  The
unexercised  portion of the  options automatically terminates  upon the first to
occur of (a) the expiration of the option term; (b) the expiration of 12  months
from  the  date of  termination of  the  optionee's employment  due to  death or
permanent  disability;   (c)   immediately   upon   the   termination   of   the
 
                                       49
<PAGE>
optionee's employment for cause; and (d) the expiration of three months from the
date  of termination of the optionee's employment  by the Company for any reason
other than (b)  or (c) above;  PROVIDED that  if the optionee  dies during  such
three-month  period, the time  of expiration of  the options is  extended for 12
months thereafter and PROVIDED, FURTHER that  if the optionee is rehired  during
the three-month period, such termination shall be deemed not to have occurred.
 
    The  provisions of the Stock Option Plan  provide for the automatic grant of
non-qualified stock  options  to  purchase shares  of  Common  Stock  ("Director
Options")  to  directors  of the  Company  who  are not  employees  or principal
stockholders of the  Company ("Eligible Directors").  Eligible Directors of  the
Company  elected after consummation of this  offering will be granted a Director
Option to purchase 5,333 shares of Common Stock on the date such person is first
elected or  appointed  a  director  (an  "Initial  Director  Option").  Further,
commencing  on the day immediately  following the date of  the annual meeting of
stockholders during the  Company's fiscal  year ending December  31, 1996,  each
Eligible  Director, other than directors who received an Initial Director Option
since the last  annual meeting, will  be granted a  Director Option to  purchase
1,333  shares of Common Stock on the  day immediately following the date of each
annual meeting of stockholders,  as long as  such director is  as member of  the
Board  of Directors.  The exercise  price for each  share subject  to a Director
Option shall be equal to the fair market  value of the Common Stock on the  date
of  grant. Director Options  are exercisable in  five equal annual installments,
commencing on  the  date of  grant  or 90  days  after the  termination  of  the
directors' service on the Board of Directors.
 
    The   following  table  sets  forth  certain  information  with  respect  to
individual grants of stock  options made during the  fiscal year ended  December
31, 1995 to each of the named executive officers:
 
                     OPTION/SAR GRANTS IN LAST FISCAL YEAR
 
<TABLE>
<CAPTION>
                                                                                                 POTENTIAL REALIZABLE
                                                                                                   VALUE AT ASSUMED
                                     NUMBER OF       % OF TOTAL                                 ANNUAL RATES OF STOCK
                                    SECURITIES      OPTIONS/SARS                                PRICE APPRECIATION FOR
                                    UNDERLYING       GRANTED TO      EXERCISE OR                     OPTION TERM
                                   OPTIONS/SARS     EMPLOYEES IN     BASE PRICE    EXPIRATION   ----------------------
NAME                                  GRANTED       FISCAL YEAR     PER SHARE (1)     DATE          5%         10%
- ---------------------------------  -------------  ----------------  -------------  -----------  ----------  ----------
<S>                                <C>            <C>               <C>            <C>          <C>         <C>
James D. Isbister................       16,667            6.5%        $    4.50       1/17/05(2) $   47,167 $  119,531
                                         5,000            1.9              4.50        3/7/05(3)     14,150     35,859
                                        54,138           21.1              4.50       5/22/05(4)    153,212    388,269
                                         6,667            2.6              4.50       12/6/05(3)     18,867     47,812
George W. Belendiuk..............        5,000            1.9%        $    4.50        3/7/05(3) $   14,150 $   35,859
                                        25,534           10.0              4.50       5/22/05(4)     72,258    183,116
                                         6,667            2.6              4.50       12/6/05(3)     18,867     47,812
Krystyna Belendiuk...............        5,000            1.9%        $    4.50        3/7/05(3) $   14,150 $   35,859
                                        25,534           10.0              4.50       5/22/05(4)     72,258    183,116
                                         6,667            2.6              4.50       12/6/05(3)     18,867     47,812
Edward M. Rudnic.................        5,000            1.9%        $    4.50        3/7/05(3) $   14,150 $   35,859
                                        11,354            4.4              4.50       5/22/05(4)     32,130     81,424
                                         6,667            2.6              4.50       12/6/05(3)     18,867     47,812
James D. Russo...................        5,000            1.9%        $    4.50        3/7/05(3) $   14,150 $   35,859
                                         6,446            2.5              4.50       5/22/05(4)     18,242     46,230
                                         6,667            2.6              4.50       12/6/05(3)     18,867     47,812
</TABLE>
 
- --------------
(1) The  Board  of  Directors  determined  that the  fair  market  value  of the
    Company's Common Stock was $4.50 on the date of grant.
 
(2) These options are immediately exercisable.
 
(3) The options become exercisable as to  twenty percent (20%) of the shares  on
    each of the first, second, third, fourth and fifth anniversaries of the date
    of grant.
 
(4) These  options are  exercisable commencing  May 1996  in annual installments
    over either two or four years.
 
                                       50
<PAGE>
    On March 6, 1996, each of Messrs. Isbister and Russo and Drs. G.  Belendiuk,
K.  Belendiuk and Rudnic were granted options to purchase 69,029, 9,888, 34,084,
33,032 and 15,974 shares of Common Stock, respectively, at an exercise price  of
the  greater of $4.50 or  85% of the initial public  offering price per share in
this offering  and exercisable  in three  equal annual  installments  commencing
March 1997. On May 14, 1996, Mr. Isbister and Dr. Rudnic were granted options to
purchase  13,333 and 6,667 shares of  Common Stock, respectively, at an exercise
price of the greater of  $4.50 or 85% of the  initial public offering price  per
share  in  this  offering  and exercisable  in  five  equal  annual installments
commencing May 1997. On July 1, 1996, Messrs. Isbister and Russo and Dr.  Rudnic
were  granted options  to purchase  40,000, 40,000  and 65,000  shares of Common
Stock, respectively, at an exercise price of the greater of $4.50 or 85% of  the
initial  public offering  price in this  offering and exercisable  in five equal
installments commencing  June  1997.  In  connection  with  his  appointment  as
President  and Chief Operating  Officer, Robert S. Cohen  was granted options to
purchase 225,000 shares of Common Stock at  an exercise price of the greater  of
$4.50 or 85% of the initial public offering price per share in this offering and
exercisable in five equal annual installments commencing July 1, 1996.
 
    The  following table  sets forth  certain information  with respect  to each
exercise of stock options during the fiscal year ended December 31, 1995 by each
of the named executive officers and the number and value of unexercised  options
held by such named executive officers as of December 31, 1995:
 
                       AGGREGATED OPTION/SAR EXERCISES IN
             LAST FISCAL YEAR AND FISCAL YEAR-END OPTION/SAR VALUES
 
<TABLE>
<CAPTION>
                                                                NUMBER OF SECURITIES
                                                               UNDERLYING UNEXERCISED      VALUE OF UNEXERCISED
                                NUMBER OF                      OPTIONS/SAR AT DECEMBER  IN-THE-MONEY OPTIONS/SARS
                                 SHARES                               31, 1995           AT DECEMBER 31, 1995 (1)
                               ACQUIRED ON                     -----------------------  --------------------------
NAME                            EXERCISE      VALUE REALIZED   EXERCISABLE/UNEXERCISABLE EXERCISABLE UNEXERCISABLE
- ----------------------------  -------------  ----------------  -----------------------  -----------  -------------
<S>                           <C>            <C>               <C>                      <C>          <C>
James D. Isbister...........       11,593       $   51,473           67,612/117,223      $  27,000    $         0
George W. Belendiuk.........        5,000       $   22,200            23,166/71,537      $   8,100    $    12,800
Krystyna Belendiuk..........       20,000       $   88,800            23,166/74,870      $   8,100    $    27,600
Edward M. Rudnic............        5,000       $   22,200            11,767/39,422      $  10,640    $     9,560
James D. Russo..............            0       $        0             3,333/31,447      $       0    $         0
</TABLE>
 
- --------------
(1) Based on the fair market value of the Company's Common Stock on December 31,
    1995 of $4.50 per share, as determined by the Company's Board of Directors.
 
PENSION PLAN
 
    The  Company maintains no  defined benefit pension plan  but does maintain a
defined contribution pension plan. Effective July 1990, the Company adopted  its
defined  contribution pension plan (the "Pension Plan") intended to be qualified
under sections  401(a) and  401(k) of  the  Internal Revenue  Code of  1986,  as
amended  (the  "Code"). All  full-time employees  of  the Company  are generally
eligible to participate in the Pension  Plan, provided they have at least  three
months  service  with the  Company,  on the  first day  of  the January  or July
following their date of  hire. Participants may elect  to defer a percentage  of
their  compensation on a  pre-tax basis as  a contribution to  the Pension Plan,
subject to maximum annual contribution limits under the Code. Highly compensated
employees are subject to additional  limitations on pre-tax contributions  under
the  Code. The Company may  make contributions to the  Pension Plan, although it
has  not  done  so  to  date.  The  Company  pays  all  costs  associated   with
administering the Pension Plan, which to date have not been material.
 
                              CERTAIN TRANSACTIONS
 
RELATED PARTIES
 
    HCV  II, HCV III and HCV IV are controlling stockholders of the Company. HCP
II, HCP III  and HCP  IV are  limited partnerships  which serve  as the  general
partner of each of HCV II, HCV III and
 
                                       51
<PAGE>
HCV  IV, respectively. Dr.  Cavanaugh, a director  of the Company,  is a general
partner of HCP II, HCP III and HCP IV. See "Principal Stockholders." HIC is  the
management  company for each of HCV I, HCV II, HCV III and HCV IV. Dr. Cavanaugh
is an officer of HIC.
 
FINANCINGS
 
    In January 1991, the Company entered into a convertible preferred stock  and
warrant  purchase agreement whereby  the Company sold  an aggregate of 2,000,000
shares of Preferred Stock to HCV  II for aggregate gross proceeds of  $2,000,000
and  sold to HCV II,  for a price of $.001  each, warrants to purchase 3,000,000
shares of Preferred Stock (the "Preferred Stock Warrants") at an exercise  price
of  $1.00  per share.  In  September 1991,  HCV  II transferred  certain  of the
Preferred Stock Warrants to certain investors and, upon exercise of 1,700,000 of
the Preferred Stock Warrants, the Company sold an additional 1,700,000 shares of
Preferred Stock, of which 1,200,000 were sold to HCV II and 500,000 were sold to
Everest Trust,  for aggregate  gross  proceeds of  $1,700,000, pursuant  to  the
exercise  of  a portion  of the  Preferred Stock  Warrants. All  Preferred Stock
Warrants held by HCV II and other investors were exercisable through January 30,
1994 at an exercise price of $1.00 per share and have expired. In April and  May
1992,   the  Company  sold  an  aggregate   of  1,300,000  and  697,337  shares,
respectively, of Preferred Stock  at a purchase  price of $1.00  per share to  a
group   of  stockholders   including  HCV   II  (876,300   and  413,379  shares,
respectively) and Everest  Trust (323,700 and  173,637 shares respectively).  In
June  1993,  the Company  entered into  a  convertible preferred  stock purchase
agreement (the  "Preferred  Stock Agreement"),  pursuant  to which  it  sold  an
aggregate  of 5,025,000 shares of  Preferred Stock at a  purchase price of $1.00
per share, to a  group of stockholders (the  "Preferred Holders") including  HCV
III,  HCV  IV, The  State  Treasurer of  the State  of  Michigan ("The  State of
Michigan"), The Aetna Casualty and  Surety Company ("Aetna") and Everest  Trust.
The  Preferred Stock Agreement provided for the  purchase of up to an additional
3,975,000 shares of  Preferred Stock  in three stages  upon the  same terms  and
conditions prior to December 31, 1994, upon notification by the Company that its
cash  and cash  equivalents have decreased  to less than  $500,000. In September
1993, November 1993 and  February 1994, an  additional 1,325,001, 1,325,000  and
1,324,999  shares of Preferred Stock, respectively, were purchased by certain of
the Preferred Holders, including HCV III, HCV  IV and The State of Michigan.  In
March  1994,  Everest Trust  transferred 393,054  shares  of Preferred  Stock to
Hudson Trust.
 
    The Company was initially funded by loans from HCV II aggregating  $768,000,
bearing  interest at the  rate of 10%  per annum on  the unpaid principal, which
were repaid, together with accrued interest, out of the proceeds of the sale  of
the  Preferred  Stock in  January  1991. In  August  1991, the  Company borrowed
$150,000 from HCV II pursuant to a promissory note bearing interest at the  rate
of  10% per  annum on  the unpaid principal,  which note,  together with accrued
interest, was repaid out of the proceeds of the exercise of the Preferred  Stock
Warrants in September 1991. In August 1992, the Company borrowed an aggregate of
$1,500,000  for  working  capital pursuant  to  a credit  agreement  between the
Company  and  certain  stockholders,  including  HCV  II  (the  "August   Credit
Agreement").  In December  1992, the  Company entered  into a  $1,000,000 credit
agreement for working capital with a group of stockholders including HCV II (the
"December Credit Agreement"). In  each of December 1992  and February 1993,  the
Company  borrowed $500,000 under the December Credit Agreement. Borrowings under
the August Credit Agreement and the  December Credit Agreement bore interest  at
the  prime rate of interest plus 1%  on the unpaid principal. In connection with
the August  Credit Agreement  and  the December  Credit Agreement,  the  Company
issued warrants to purchase an aggregate of 111,111 shares of Common Stock at an
exercise price of $.06 per share (the "Common Stock Warrants"), 107,960 of which
were issued to HCV II and the remainder of which were issued to other investors.
At  the dates  the Common  Stock Warrants  were issued,  the Company's  Board of
Directors had valued the Company's Common Stock at $2.88 per share. In  December
1992,  HCV II, Everest Trust and  certain stockholders purchased 139,518, 22,422
and 4,729 shares of Common Stock,  respectively. Pursuant to a credit  agreement
in  April 1993 (the "April Credit Agreement"), the Company borrowed an aggregate
of approximately $515,000  from a  group of  stockholders including  HCV II.  In
connection  with the April Credit Agreement,  the Company issued Preferred Stock
Warrants to purchase up to 41,667 shares of Preferred Stock at an exercise price
of $1.00  per  share to  HCV  II and  1,686  Common Stock  warrants  to  certain
shareholders  of which  802 remain  outstanding and  884 were  converted. In May
1993, the Company
 
                                       52
<PAGE>
borrowed $100,000,  $150,200  and $49,800  from  HCV II,  HCV  III and  HCV  IV,
respectively, pursuant to promissory notes bearing interest at the prime rate of
interest  plus  1% on  the  unpaid principal.  All  of the  foregoing  notes and
borrowings were repaid in June 1993, together with accrued interest of  $36,452,
out  of the  proceeds received  by the  Company from  the sale  of the Preferred
Stock.
 
    In June  1993,  the  Company  entered into  a  Third  Amended  and  Restated
Stockholders   Agreement  with   all  holders   of  its   Preferred  Stock  (the
"Stockholders  Agreement")   which   grants  certain   demand   and   piggy-back
registration  rights  with  respect  to shares  of  Common  Stock  issuable upon
conversion of all  outstanding shares  of Preferred Stock.  See "Description  of
Capital Stock -- Registration Rights." The Stockholders Agreement also grants to
the  holders of the Preferred Stock certain other rights with respect to voting,
pre-emptive rights with  respect to the  acquisition and sale  of shares by  the
Company  and certain  matters affecting  corporate governance.  The Stockholders
Agreement will be amended prior to the completion of this offering to  eliminate
these rights (other than registration rights).
 
    In  May 1994, the Company entered into  the 1994 Credit Agreement (the "1994
Credit Agreement") with certain stockholders, including HCV III, HCV IV,  Aetna,
The  State of Michigan, and Everest Trust (the "1994 Lenders") pursuant to which
the 1994 Lenders agreed to loan the  Company up to $4,395,000 through May  1995.
Through  May  1995, the  Company borrowed  $2,000,000  under this  agreement and
issued $2,000,000 principal amount of  promissory notes bearing interest at  the
rate  of 7 1/4% per annum (the "1994 Notes") convertible into Preferred Stock to
the 1994 Lenders.  Also, in  connection with the  execution of  the 1994  Credit
Agreement,  the Company issued warrants to purchase up to an aggregate of 33,337
shares of Common Stock to the Lenders at an exercise price of $10.80 per  share.
See "Description of Capital Stock."
 
    In  May  1995,  the  Company  entered  into  a  Conversion  and Subscription
Agreement (the "Conversion Agreement"), as amended in October 1995, at the  same
time  it entered into the 1995 Credit  Agreement with the 1994 Lenders. Pursuant
to the Conversion Agreement, the  outstanding principal amount of $2,000,000  of
the 1994 Notes converted into Preferred Stock at a conversion price of $1.25 per
share,  resulting in the issuance of 1,599,997 Preferred Stock Adjustment Shares
(the "Adjustment Shares") of the Company to the 1994 Lenders. In February  1996,
the  conversion price of the 1994 Notes was further adjusted to $0.75 per share,
resulting in the issuance of an  additional 1,066,663 shares of Preferred  Stock
to  the 1994  Lenders. As  a result  of this  adjustment, there  was a mandatory
adjustment to the conversion ratio of all Preferred Stock to one share of Common
Stock for each four and one-half shares of Preferred Stock (after giving  effect
to a one-for-six reverse stock split of the Common Stock).
 
    The  1995 Credit Agreement permitted the  Company to borrow up to $8,000,000
through January 15, 1997 from  certain stockholders and officers, including  HCV
III,  HCV IV,  The State of  Michigan, Everest  Trust, James D.  Russo, James D.
Isbister and George W. Belendiuk (the  "1995 Lenders"). The Company borrowed  an
aggregate  of $8,000,000 under the 1995 Credit Agreement and issued an aggregate
of $8,000,000  in  principal amount  of  notes (the  "Convertible  Notes").  The
Convertible  Notes,  which bore  interest  at the  rate  of 9%  per  annum, were
converted into  8,000,000 shares  of Preferred  Stock in  March 1996.  The  1995
Credit  Agreement also  provided for  the issuance  by the  Company to  the 1995
Lenders of 1,200,000 Preferred Stock Warrants at an exercise price of $0.96  per
share.
 
    In  October 1995, in connection  with a commitment by HCV  III and HCV IV to
loan up to $3,000,000  to the Company under  certain circumstances, the  Company
agreed  to issue  to such  holders warrants to  purchase an  aggregate of 50,000
shares of Common  Stock for a  10-year term at  an exercise price  equal to  the
initial public offering price of the Common Stock.
 
    In  March 1996, the Company entered  into two credit agreements with certain
stockholders (collectively the "1996 Credit  Agreement"), including HCV II,  HCV
III,  HCV IV, Everest  Trust, James D.  Russo and Max  Link (the "1996 Lenders")
pursuant to  which the  1996  Lenders have  agreed to  loan  the Company  up  to
$7,300,000  through the  consummation of  this offering  at an  interest rate of
8 1/2%. The terms  of the two  credit agreements are  identical except that  the
first agreement, which provides for borrowing of up to $4,300,000, must be fully
drawn  before any borrowings may  be made under the  second agreement. The loans
are due  May  31,  1997, and  are  convertible  in  the event  of  a  merger  or
acquisition  of the Company into  Preferred Stock at $1.25  per share, or in the
event of an initial public offering, at one-half of the initial public  offering
price  per  share. In  connection with  the 1996  Credit Agreement,  the Company
issued 730,000  warrants to  purchase  shares of  Preferred  Stock to  the  1996
Lenders  at an exercise price of $0.75 per share and is committed to issue up to
365,000 additional warrants based  upon actual funding of  loans at the rate  of
one
 
                                       53
<PAGE>
warrant for each $20.00 of actual borrowing. On each of March 8, 1996, April 25,
1996  and June 11,  1996, the Company  borrowed $1,000,000, for  an aggregate of
$3,000,000, under the 1996 Credit Agreement  and issued an aggregate of  150,000
warrants  to purchase Preferred Stock to the  1996 Lenders under the 1996 Credit
Agreement. All of the foregoing warrants expire in March 2006.
 
                                       54
<PAGE>
                             PRINCIPAL STOCKHOLDERS
 
    The  following table sets forth certain information regarding the beneficial
ownership of the capital  stock of the Company  as of July 1,  1996 by (i)  each
person  known to the Company to  be the beneficial owner of  more than 5% of the
capital stock  of  the Company  (ii)  all Directors,  (iii)  each of  the  named
executive  officers and  (iv) all Directors  and executive officers  as a group,
prior to  this offering  and as  adjusted  to give  effect to  the sale  of  the
2,200,000 shares offered hereby.
 
<TABLE>
<CAPTION>
                                                                                                    PERCENTAGE OF
                                                                                                  OUTSTANDING SHARES
                                                                            NUMBER OF SHARES   ------------------------
                                                                              BENEFICIALLY       BEFORE        AFTER
NAME AND ADDRESS OF BENEFICIAL OWNER (1)                                       OWNED (2)        OFFERING     OFFERING
- -------------------------------------------------------------------------  ------------------  -----------  -----------
<S>                                                                        <C>                 <C>          <C>
HealthCare Ventures II, L.P..............................................     1,431,528(3)           21.6%        16.2%
HealthCare Ventures III, L.P.............................................     2,539,454(3)           37.9%        28.5%
HealthCare Ventures IV, L.P..............................................       745,754(3)           11.4%         8.5%
State Treasurer of The State of Michigan.................................       962,893(4)           14.7%        11.0%
Rho Management Trust II..................................................       646,643(5)            9.8%         7.4%
Aetna Life Insurance Company.............................................       330,002(6)            5.1%         3.8%
James H. Cavanaugh, Ph.D.................................................     4,716,736(3)(7)        70.9%        53.3%
Joshua Ruch..............................................................       646,643(8)            9.8%         7.4%
James D. Isbister........................................................       167,389(9)            2.5%         1.9%
Krystyna Belendiuk, Ph.D.................................................       143,612(10)           2.2%         1.6%
Edward M. Rudnic, Ph.D...................................................        25,307(11)         *            *
James D. Russo...........................................................        67,057(12)           1.0%       *
Max Link, Ph.D...........................................................        21,418(13)         *            *
Lawrence C. Hoff.........................................................             0             *            *
All Directors and Officers as a group (9 persons)........................     5,192,047(14)          72.1%        55.2%
</TABLE>
 
- --------------
 *  Less than 1%.
 
 (1)Except  as otherwise indicated, the address  of each beneficial owner is c/o
    the Company, 1550 East Gude Drive, Rockville, MD 20850.
 
 (2)Except as otherwise  indicated, each of  the parties listed  above has  sole
    voting and investment power over the shares owned.
 
 (3)The  address for HCV II, HCV III, HCV IV and Dr. Cavanaugh is Twin Towers at
    Metro Park,  379  Thornall Street,  Edison,  New Jersey  08837.  The  shares
    beneficially  owned by HCV II include  153,189 shares subject to immediately
    exercisable warrants.  The  shares beneficially  owned  by HCV  III  include
    230,974  shares  subject  to immediately  exercisable  warrants.  The shares
    beneficially owned by HCV  IV include 67,856  shares subject to  immediately
    exercisable warrants.
 
 (4)As  Custodian of  the Michigan  Public School  Employees' Retirement System,
    State Employees' Retirement System, Michigan State Police Retirement  System
    and  Michigan Judges Retirement System. The  address for The State Treasurer
    of the  State  of  Michigan  is c/o  Treasury  Department,  Venture  Capital
    Division,  430 West Allegan, Lansing, Michigan 48922. Includes 62,568 shares
    subject to immediately exercisable warrants.
 
 (5)Managed by Rho Management  Company, Inc. with offices  at 767 Fifth  Avenue,
    New York, New York 10153. The shares beneficially owned by the Trust include
    104,258 shares subject to immediately exercisable warrants. Does not include
    shares  owned by HCV IV. Rho Management  Trust II (formerly known as Everest
    Trust) is a principal limited partner of HCV IV and Rho Management  Company,
    Inc.  may be deemed  to be the  beneficial owner of  shares owned by Everest
    Trust.
 
 (6)The address for Aetna Life Insurance Company is IG7F, 151 Farmington Avenue,
    Hartford, Connecticut 06103. Includes  12,342 shares subject to  immediately
    exercisable warrants.
 
 (7)Dr.  Cavanaugh, a director of the Company, is one of the General Partners of
    HCP II, HCP III and HCP IV, the General Partners of HCV II, HCV III and  HCV
    IV, respectively, and, accordingly, may be deemed to be the beneficial owner
    of shares owned by HCV II, HCV III and HCV IV.
 
                                       55
<PAGE>
 (8)Mr.   Ruch  is  the  President,  Chief  Executive  Officer  and  controlling
    shareholder of Rho Management Company,  Inc., the investment adviser to  Rho
    Management  Trust II,  and accordingly  may be  deemed to  be the beneficial
    owner of shares owned by Rho Management Trust II.
 
 (9)Includes 2,507  shares  subject  to immediately  exercisable  warrants,  and
    90,197  shares issuable  upon exercise of  options to  purchase Common Stock
    within the next 60 days; also includes beneficial ownership of 3,148  shares
    of Common Stock owned by K.D. Hammond, 3,148 shares of Common Stock owned by
    J.M.  Hammond and 3,148  shares of Common Stock  owned by A.C. Kalavritinos,
    his grandchildren and 2,223 owned by W.J. Kalavritinos, his daughter.
 
(10)Includes 42,196 shares issuable upon exercise of options to purchase  Common
    Stock  within 60  days. Includes  beneficial ownership  of 16,712  shares of
    Common Stock, 2,507 shares subject  to immediately exercisable warrants  and
    38,863  shares of Common Stock issuable upon exercise of options exercisable
    within 60  days  in  the  Estate  of  George  W.  Belendiuk;  also  includes
    beneficial  ownership  of  12,592  shares  of  Common  Stock  owned  by A.P.
    Belendiuk and 12,592  shares of Common  Stock owned by  K.A. Belendiuk,  her
    children.
 
(11)Includes  20,307 shares  of Common Stock  issuable upon  exercise of options
    exercisable within 60 days.
 
(12)Includes 13,334  shares subject  to  immediately exercisable  warrants,  and
    9,278  shares issuable  upon exercise  of options  to purchase  Common Stock
    exercisable within 60 days.
 
(13)Includes 2,997 shares subject to  immediately exercisable warrants, and  744
    shares   issuable  upon  exercise  of   options  to  purchase  Common  Stock
    exercisable within 60 days.
 
(14)Includes 473,364  shares subject  to  immediately exercisable  warrants  and
    252,112 shares subject to options exercisable within 60 days.
 
                          DESCRIPTION OF CAPITAL STOCK
 
    Upon  consummation of  this offering,  the authorized  capital stock  of the
Company will consist of 25,000,000 shares  of Common Stock, par value $0.01  per
share, and 5,000,000 shares of Preferred Stock, par value $0.01 per share.
 
COMMON STOCK
    Upon consummation of this offering, there will be 8,672,332 shares of Common
Stock  outstanding. Holders of  Common Stock are  entitled to one  vote for each
share held of record  on all matters  submitted to a  vote of the  stockholders.
Subject  to preferences that may be applicable to any then outstanding Preferred
Stock, holders of Common Stock are entitled to receive ratably such dividends as
may be  declared  by the  Board  of Directors  out  of funds  legally  available
therefor.  In  the event  of a  liquidation,  dissolution or  winding up  of the
Company, holders of  Common Stock are  entitled to share  ratably in all  assets
remaining  after payment  of liabilities and  the liquidation  preference of any
then outstanding Preferred  Stock. Holders  of Common Stock  have no  preemptive
rights and no right to convert their Common Stock into any other securities.
 
PREFERRED STOCK
    All  outstanding shares of  Preferred Stock will  automatically convert into
shares of Common Stock upon  consummation of this offering  on the basis of  one
share of Common Stock for each four and one-half shares of Preferred Stock. Such
shares will be retired and will not be available for reissuance. See Notes 5 and
11  of  Notes  to  Financial  Statements  for  a  description  of  the currently
outstanding Preferred  Stock and  "Capitalization." Accordingly,  following  the
completion  of this offering,  no shares of Preferred  Stock will be outstanding
and all Preferred  Stock Warrants will  be converted into  warrants to  purchase
Common Stock.
 
    The  Company's amended Certificate of  Incorporation authorizes the issuance
of an additional 5,000,000  shares of preferred stock.  The Board of  Directors,
within  the  limitations  and  restrictions  contained  in  the  Certificate  of
Incorporation and without  further action  by the  Company's stockholders,  will
have the authority to issue up to 5,000,000 additional shares of preferred stock
in  one  or more  series  and to  fix  the rights,  preferences,  privileges and
restrictions thereof,  including  dividend  rights,  conversion  rights,  voting
rights,  terms of redemption,  liquidation preferences and  the number of shares
constituting any  series or  the designation  of such  series. The  issuance  of
preferred  stock could  adversely affect the  voting power of  holders of Common
Stock and could have the effect of delaying, deferring or preventing a change in
control of the Company. The Company has  no present plan to issue any shares  of
preferred stock.
 
                                       56
<PAGE>
WARRANTS
    Upon  consummation  of  this  offering, the  Company  will  have outstanding
warrants to purchase an aggregate of 110,260 shares of Common Stock at $0.06 per
share, which warrants are exercisable through June 30, 2003 and March 15,  2003,
warrants  to purchase up to an aggregate  of 33,337 shares of Common Stock which
are exercisable through May 3, 2004 at $10.80 per share, warrants to purchase up
to 9,260  shares of  Common Stock  through April  6, 2003  at $4.50  per  share,
warrants  to  purchase  266,670 shares  of  Common Stock  which  are exercisable
through May 22, 2005 at $4.32 per share, warrants to purchase 195,556 shares  of
Common Stock which are exercisable through March 8, 2006 at $3.375 per share and
warrants to purchase 50,000 shares of Common Stock at an exercise price equal to
the  initial public offering price per share which are exercisable through March
8, 2006. See "Certain Transactions."
 
REGISTRATION RIGHTS
    Upon the closing of the offering, the holders of shares of 6,260,569  Common
Stock  and warrants to purchase 665,084 shares  of Common Stock will be entitled
to demand and "piggyback" registration rights with respect to such shares. Under
the Stockholders Agreement between  the Company and  these holders, the  holders
may  request that the Company file a registration statement under the Securities
Act, and, subject to certain conditions, the Company generally will be  required
to  use its  best efforts to  effect any  such registration. The  Company is not
generally required to effect  more than two  such registrations, although  under
certain  circumstances the  holders will  have the  right to  request additional
registrations. In  addition, if  the Company  proposes to  register any  of  its
securities, either for its own account or for the account of other stockholders,
the  Company  is  required,  with  certain  exceptions,  to  notify  the holders
described above  and,  subject  to  certain  limitations,  to  include  in  such
registration  all of the shares of Common Stock requested to be included by such
holders. Each of  the holders described  above has waived  its right to  include
shares  held  thereby in  the  offering made  hereby.  The Company  is generally
obligated to  bear the  expenses, other  than underwriting  discounts and  sales
commissions, of all of these registrations.
 
    Any  exercise of such registration rights  may hinder efforts by the Company
to arrange future financings of  the Company and may  have an adverse effect  on
the market price of the Company's Common Stock.
 
TRANSFER AGENT
    American  Stock Transfer  & Trust Company  serves as Transfer  Agent for the
shares of Common Stock.
 
SECTION 203 OF THE DELAWARE GENERAL CORPORATION LAW
 
    Section 203 of the Delaware  General Corporation Law (the "DGCL")  prohibits
certain   transactions  between  a  Delaware   corporation  and  an  "interested
shareholder," which is  defined as a  person who, together  with any  affiliates
and/or  associates of such person, beneficially owns, directly or indirectly, 15
percent or more of the outstanding voting shares of a Delaware corporation. This
provision prohibits certain  business combinations (defined  broadly to  include
mergers,  consolidations,  sales  or  other  dispositions  of  assets  having an
aggregate value  of  10  percent or  more  of  the consolidated  assets  of  the
corporation,  and  certain  transactions  that  would  increase  the  interested
shareholder's proportionate  share  ownership  in the  corporation)  between  an
interested  shareholder and a corporation for a  period of three years after the
date the interested  shareholder acquired  its stock, unless:  (i) the  business
combination  is approved  by the corporation's  board of directors  prior to the
date the interested shareholder acquired shares; (ii) the interested shareholder
acquired at least  85 percent  of the  voting stock  of the  corporation in  the
transaction  in which it became an  interested shareholder or (iii) the business
combination is approved  by a  majority of  the board  of directors  and by  the
affirmative  vote  of  two-thirds  of  the  outstanding  voting  stock  owned by
disinterested  shareholders  at  an  annual  or  special  meeting.  A   Delaware
corporation,  pursuant to  a provision  in its  certificate of  incorporation or
by-laws, may elect not to  be governed by Section 203  of the DGCL. The  Company
will  not make such an election and, as a result, the Company will be subject to
the provisions of Section 203 of the DGCL upon consummation of the offering.
 
    At this time, the Company will not  seek to "elect out" of the statute  and,
therefore, upon consummation of this offering and the registration of its shares
of  Common Stock  under the  Securities Exchange  Act of  1934, the restrictions
imposed by Section 203 of the DGCL will apply to the Company.
 
                                       57
<PAGE>
                        SHARES ELIGIBLE FOR FUTURE SALE
 
    Upon consummation of this offering the Company will have 8,672,332 shares of
Common Stock outstanding, assuming that the Underwriters' over-allotment  option
and  other outstanding options and warrants  are not exercised. Of these shares,
the  2,200,000  shares  offered  hereby  will  be  freely  transferable  without
restriction  or further registration  under the Securities  Act, except that any
shares owned by affiliates of the Company will be subject to the limitations  of
Rule  144 under  the Securities  Act. All  remaining shares  will be "restricted
securities" and may not  be sold publicly unless  they are registered under  the
Securities  Act  or  are sold  pursuant  to  Rule 144  or  other  exemption from
registration. Of  the shares  of  Common Stock  outstanding, 3,507,582  of  such
shares  will be eligible for sale in the public market in reliance upon Rule 144
commencing 90 days after  the date of this  Prospectus. The Company's  directors
and   executive  officers  and  certain  stockholders,  beneficially  owning  an
aggregate of  7,569,968  shares  of Common  Stock  (including  3,752,114  shares
eligible  for sale commencing 90  days after the date  of this Prospectus), have
agreed with the Underwriters not to sell  or otherwise dispose of any shares  of
Common  Stock  or  other capital  stock  of  the Company,  with  certain limited
exceptions, without the prior written consent of Lehman Brothers Inc. on  behalf
of  the  Representatives  for  a period  of  180  days after  the  date  of this
Prospectus. See "Underwriting."
 
    In general under Rule 144 as currently in effect, a person (or persons whose
shares are aggregated), including persons who  may be deemed to be  "affiliates"
of  the Company as that term is defined under the Securities Act, is entitled to
sell within any three-month period a  number of restricted shares that does  not
exceed  the greater  of (i) 1%  of the  then outstanding shares  of Common Stock
(approximately 86,700  shares  immediately  after  this  offering,  assuming  no
exercise of the Underwriters' over-allotment option), or (ii) the average weekly
trading volume in the Common Stock during the four calendar weeks preceding such
sale;  provided that at least two years have elapsed since the later of the date
such securities  were acquired  from the  Company or  from an  affiliate of  the
Company. Sales under Rule 144 are also subject to certain requirements as to the
manner  of sale, notice and the availability of current public information about
the Company. However,  a person  who is not  an affiliate  and has  beneficially
owned  such shares  for at  least three  years is  entitled to  sell such shares
without regard to  the volume  or other  resale requirements;  provided that  at
least  three years  have elapsed  since the  later of  the date  the shares were
acquired from the Company or from an affiliate of the Company.
 
    Rule  701  under  the  Securities   Act  provides  an  exemption  from   the
registration  requirements of the Act for  offers and sales of securities issued
pursuant to  certain compensatory  benefit plans,  such as  the Company's  Stock
Option  Plan, of a company not subject  to the reporting requirements of Section
13 or 15(d)  of the Exchange  Act. Securities  issued pursuant to  Rule 701  are
defined  as restricted  securities for  purposes of  Rule 144.  However, 90 days
after the issuer  becomes subject to  the reporting provisions  of the  Exchange
Act,  the  Rule 144  resale restrictions,  except  for the  broker's transaction
requirement, are inapplicable for non-affiliates. Affiliates are subject to  all
Rule  144 restrictions after this 90-day  period, except for the holding period.
If all the requirements of  Rule 701 are met,  an aggregate of 1,274,849  shares
issuable  or issued on  exercise of stock  options which are  outstanding may be
sold pursuant to such rule, although approximately 1,059,019 of these shares are
subject to the lock-up agreements described above.
 
    The holders  of 7,015,616  shares  of Common  Stock, including  warrants  to
purchase  Common Stock and  Preferred Stock have  certain demand and "piggyback"
registration rights. These  holders have waived  their registration rights  with
respect  to this offering and have agreed not to exercise such rights during the
period commencing 180 days  from the date hereof  without the consent of  Lehman
Brothers Inc. See "Description of Capital Stock -- Registration Rights."
 
    Prior  to this  offering, there  has been  no public  market for  the Common
Stock, and  there is  no assurance  that an  active market  will develop  or  be
sustained after this offering. No predictions can be made of the effect, if any,
that  sales of Common  Stock or the  availability of Common  Stock for sale will
have on  the market  price of  such  securities prevailing  from time  to  time.
Nevertheless,  sales of substantial amounts of Common Stock in the public market
could adversely affect prevailing market prices.
 
                                       58
<PAGE>
                                  UNDERWRITING
 
    Under the terms and subject to the conditions contained in the  Underwriting
Agreement,  the  form  of which  is  filed  as an  exhibit  to  the Registration
Statement of which this Prospectus forms  a part, the Underwriters named  below,
for  whom  Lehman  Brothers  Inc.  and Volpe,  Welty  &  Company  are  acting as
representatives (the "Representatives"), have severally agreed to purchase  from
the  Company,  and the  Company  has agreed  to  sell to  each  Underwriter, the
aggregate number of shares of Common Stock  set forth opposite the name of  each
such Underwriter below:
 
<TABLE>
<CAPTION>
                                                                                   NUMBER OF
UNDERWRITER                                                                          SHARES
- ---------------------------------------------------------------------------------  ----------
<S>                                                                                <C>
Lehman Brothers Inc..............................................................
Volpe, Welty & Company...........................................................
 
                                                                                   ----------
    Total........................................................................   2,200,000
                                                                                   ----------
                                                                                   ----------
</TABLE>
 
    The  Company has been  advised by the  Representatives that the Underwriters
propose to offer the shares of Common Stock to the public at the initial  public
offering  price set forth  on the cover  page hereof, and  to certain dealers at
such initial public offering  price less a selling  concession not in excess  of
$     per share.  The Underwriters may  allow, and  such dealers  may reallow, a
concession not in excess of  $   per share  to certain other Underwriters or  to
certain  other brokers or dealers. After the initial offering to the public, the
offering price and other selling terms may be changed by the Representatives.
 
    The Underwriting  Agreement provides  that the  obligations of  the  several
Underwriters  to  pay for  and accept  delivery  of the  shares of  Common Stock
offered hereby are subject to approval  of certain legal matters by counsel  and
to  certain  other  conditions,  including  the  condition  that  no  stop order
suspending the effectiveness of the Registration  Statement is in effect and  no
proceedings  for such  purpose are pending  or threatened by  the Securities and
Exchange Commission  (the "Commission")  and  that there  has been  no  material
adverse  change  or any  development  involving a  prospective  material adverse
change in the condition of the Company  from that set forth in the  Registration
Statement  otherwise than as  set forth or contemplated  in this Prospectus, and
that certain  certificates, opinions  and letters  have been  received from  the
Company and its counsel and independent auditors. The Underwriters are obligated
to  take and pay for all of the above  shares of Common Stock if any such shares
are taken.
 
    The Company and the Underwriters  have agreed in the Underwriting  Agreement
to indemnify each other against certain liabilities, including liabilities under
the Securities Act.
 
    The  Company has granted to the Underwriters  an option to purchase up to an
additional  330,000  shares  of  Common  Stock,  exercisable  solely  to   cover
over-allotments,  at the  initial public  offering price,  less the underwriting
discounts and  commissions shown  on the  cover page  of this  Prospectus.  Such
option  may  be exercised  at  any time  until  30 days  after  the date  of the
Underwriting Agreement.  To  the  extent  that the  option  is  exercised,  each
Underwriter  will be committed to purchase a  number of the additional shares of
Common Stock proportionate to such Underwriter's initial commitment as indicated
in the preceding table.
 
    The Representatives of the Underwriters  have informed the Company that  the
Underwriters do not intend to confirm sales to accounts over which they exercise
discretionary authority.
 
    Stockholders of the Company, including the directors and executive officers,
beneficially  owning an aggregate of 7,569,968 shares of Common Stock (including
shares  that  will  be  issued  upon  conversion  of  the  Preferred  Stock  and
Convertible Notes and shares that may be issued upon the exercise of outstanding
 
                                       59
<PAGE>
options and warrants) have agreed not to, directly or indirectly, offer, sell or
otherwise  dispose  of shares  of Common  Stock  or other  capital stock  of the
Company, or any securities convertible into,  or exchangeable for or any  rights
to  acquire, Common Stock  or other capital  stock of the  Company, with certain
limited exceptions, for a  period of 180  days after the  date of this  offering
without  the prior  written consent  of Lehman  Brothers Inc.  on behalf  of the
Representatives. Except for  the Common Stock  to be sold  in the offering,  the
Company  has agreed not to offer, sell,  contract to sell or otherwise issue any
shares of Common Stock (other than the shares being offered hereby and shares to
be issued upon conversion of the Preferred Stock and Convertible Notes) or other
capital stock or  any securities convertible  into or exchangeable  for, or  any
rights  to acquire,  Common Stock or  other capital stock,  with certain limited
exceptions, prior to the expiration of 180 days from the date of this Prospectus
without the  prior written  consent of  Lehman Brothers  Inc. on  behalf of  the
Representatives.
 
    Athena has been granted the right to purchase 220,000 shares of Common Stock
in this offering.
 
    Prior  to this  offering, there  has been  no public  market for  the Common
Stock. The initial public offering price will be negotiated between the  Company
and  the Representatives. Among the factors  to be considered in determining the
initial public offering price of the Common Stock, in addition to the prevailing
market  conditions,  will  be  the  Company's  historical  performance,  capital
structure,  estimates of  the business potential  and earnings  prospects of the
Company, an  assessment of  the Company's  management and  consideration of  the
above  factors  in  relation  to  market  values  of  the  companies  in related
businesses.
 
                                 LEGAL MATTERS
 
    The validity of the  securities offered hereby will  be passed upon for  the
Company  by Bachner, Tally, Polevoy & Misher LLP, New York, New York and for the
Underwriters by Shearman & Sterling, New York, New York. The statements in  this
Prospectus  under the  captions "Risk  Factors --  Uncertain Ability  to Protect
Proprietary Technology"  and  "Business  -- Patents,  Licenses  and  Proprietary
Rights"  and other  references herein  to patent  and licensing  matters will be
passed upon  by Carella,  Byrne,  Bain, Gilfillan,  Cecchi, Stewart  &  Olstein,
Roseland, New Jersey, patent counsel to the Company. A member of Carella, Byrne,
Bain,  Gilfillan, Cecchi, Stewart & Olstein holds a limited partnership interest
in each of HCV I,  HCV II and HCV III.  The statements in this Prospectus  under
the  captions  "Risk  Factors  --  No  Assurance  of  FDA  Approval;  Government
Regulation," "Risk Factors -- Possible Delay in Bringing to Market  Reformulated
Drug  Products"  and "Business  -- Government  Regulation" and  other references
herein to FDA regulatory matters will be passed upon by Olsson, Frank and Weeda,
P.C., regulatory counsel to the Company.
 
                                    EXPERTS
 
    The balance sheets as of  December 31, 1994 and  1995 and the statements  of
operations,  stockholders' deficit and cash flows for each of the three years in
the period  ended  December 31,  1995,  and for  the  period February  16,  1990
(inception)  to December 31, 1995 included in this Prospectus have been included
herein in reliance  upon the  report of  Coopers &  Lybrand L.L.P.,  independent
accountants,  given on the authority  of that firm as  experts in accounting and
auditing.
 
                             ADDITIONAL INFORMATION
 
    The Company  has  filed a  Registration  Statement  on Form  S-1  under  the
Securities  Act  with the  Commission in  Washington, D.C.  with respect  to the
shares of Common  Stock offered hereby.  This Prospectus, which  is part of  the
Registration Statement, does not contain all of the information set forth in the
Registration  Statement  and the  exhibits  and schedules  thereto.  For further
information with respect  to the Company  and the Common  Stock offered  hereby,
reference  is hereby  made to the  Registration Statement and  such exhibits and
schedules, which may be inspected without charge at the office of the Commission
at 450 Fifth Street, N.W., Washington, D.C. 20549. Reports and other information
filed by the  Company with the  Commission can  be inspected and  copied at  the
public  reference  facilities  maintained  by the  Commission  at  the following
addresses: New York  Regional Office, Seven  World Trade Center,  New York,  New
York
 
                                       60
<PAGE>
10048;  and Chicago Regional  Office, Citicorp Center,  500 West Madison Street,
Chicago, Illinois 60661-2511. Copies of such  material can be obtained from  the
Public   Reference  Section  of  the  Commission  at  450  Fifth  Street,  N.W.,
Washington, D.C.  20549  at  prescribed  rates.  Statements  contained  in  this
Prospectus  as to the contents of any contract or other document referred to are
not necessarily complete and in each instance  reference is made to the copy  of
such  contract or  document filed as  an exhibit to  the Registration Statement,
each such statement being qualified in all respects by such reference.
 
    The  Company  intends  to  furnish  its  stockholders  with  annual  reports
containing  audited financial  statements audited  by its  independent certified
public accountants and with  quarterly reports for the  first three quarters  of
each fiscal year containing unaudited interim financial information.
 
                                       61
<PAGE>
                                    GLOSSARY
 
AGONIST:   A  chemical substance  or drug  that is  capable of  combining with a
receptor on a  cell and initiating  a reaction  or activity similar  to that  of
    another chemical substance or drug.
 
ANDA:   Abbreviated  New Drug Application.  An application  submitted by generic
firms to gain  marketing approval  for a  version of  a marketed  drug based  on
    bioequivalence studies.
 
ANTAGONIST:   A chemical substance  or drug that acts  within the body to reduce
the physiological activity of another chemical substance.
 
ANTICONVULSANT:   An  agent preventing  or  arresting convulsions  or  seizures,
including seizures resulting from epilepsy.
 
APNEA:    Transient cessation  of respiration,  whether  normal or  abnormal, as
caused by certain drugs.
 
BENZODIAZEPINE:  Any of a group of aromatic lipophilic amines, such as  diazepam
and chlordiazepoxide, used as tranquilizers.
 
BIOAVAILABILITY:   An absolute term that  indicates measurement of both the rate
and total amount (extent) of drug  that reaches the general circulation from  an
    administered dosage form.
 
BIOEQUIVALENCE:   A relative term that  compares the bioavailability of one drug
product with another or with a set of standards.
 
BIOLOGIC:  Any virus, therapeutic serum, toxin, antitoxin, vaccine, blood, blood
component or derivative, allergenic product or analogous product or arsphenamine
    or its  derivatives  (or  any other  trivalent  organic  arsenic  compound),
    applicable  to the prevention, treatment, or cure of disease, or injuries in
    man.
 
BUCCAL:  Pertaining to  the cheek, or  to the cavity between  the upper gum  and
lip.
 
DOPAMINE:    A monoamine  that  is a  decarboxylated  form of  dopa  and occurs,
especially as a  neurotransmitter, in the  brain and as  an intermediate in  the
    biosynthesis of epinephrine.
 
DOPAMINERGIC:      Relating  to,   participating   in,  or   activated   by  the
neurotransmitter activity of dopamine or related substances.
 
DOSAGE FORM:   The administered version  of a  drug product, such  as a  tablet,
capsule, syrup, etc.
 
EMESIS:  Vomiting.
 
EXCIPIENTS:   Inactive ingredients  that facilitate the  preparation of a dosage
form.
 
FLUX ENHANCER:   A  chemical that  improves the  transport of  a drug  across  a
biological barrier, such as skin.
 
HYDROPHOBIC:  A substance that does not dissolve in or mix well with water, or a
substance that repels water in the extreme.
 
HYDROPHILIC:  A substance that dissolves readily in, or mixes easily with water.
 
IDDM:  Insulin-dependent diabetes mellitus.
 
IND:   Investigational New Drug Exemption. The application to the FDA requesting
the shipment  in interstate  commerce  of an  experimental  new drug  for  human
    experimentation.  The IND  typically contains pre-clinical  and some limited
    clinical data  and  information and  the  protocol  or plan  for  the  human
    clinical  trial. The FDA has  30 days from receipt  to review and approve or
    deny the IND.  An IND becomes  effective 30  days after receipt  by the  FDA
    unless  the  FDA notifes  the  sponsor not  to  proceed with  human clinical
    testing.
 
INJECTABLE:  Denoting a fluid to be introduced into one of the cavities  beneath
the skin, or into a blood vessel.
 
                                      G-1
<PAGE>
MAO-B:    Monoamine Oxidase,  Type B.  An  enzyme that  metabolizes a  number of
chemicals including dopamine.
 
MICROEMULSION:   A  formulation consisting  of  a surfactant  (and  sometimes  a
cosurfactant), an oily phase and an aqueous phase.
 
MIVACURIUM:    A  basic compound  that  acts  similarly to  curare  and  is used
intravenously, chiefly in the form of a hydrated chloride, as a muscle  relaxant
    in surgery.
 
NDA:   New Drug Application. The application  submitted and reviewed by the FDA,
of the data on the safety and efficacy of a chemical entity. Approval of an  NDA
    allows marketing of the product.
 
NIDDM:  Non-insulin dependent diabetes mellitus.
 
PARENTERAL:   Referring  to the introduction  of substances into  an organism by
means  other  than  through  the  gastrointestinal  tract  (e.g.,   intravenous,
    intramuscular, subcutaneous).
 
PEPTIDE:  A small protein consisting of fifty amino acids or less.
 
PERMEABLE:   The  ability of  a substance  to cross  a barrier,  such as  a drug
crossing a biological membrane.
 
PLA:  Product License  Application. The equivalent of  a "New Drug  Application"
("NDA") for biologics.
 
PLASMA FRACTIONS:  Components of plasma separated on the basis of differences in
physical or chemical properties.
 
SBIR  GRANT:   Small Business Innovation  Research Grant. A  mechanism to obtain
research grants from the federal government for small business.
 
SUCCINYLCHOLINE:    A   compound  similar   to  curare   that  is   administered
intravenously as a muscle relaxant during surgery.
 
TITRATION:  The method or process used by physicians, of gradually adjusting the
dosage  of  a drug  administered to  achieve the  desired clinical  result while
    seeking to minimize adverse side effects.
 
TRANSDERMAL:  Transcutaneous, passing, entering or made by, penetration  through
the skin.
 
TRANSMUCOSAL:   Penetration through the mucous  membranes of the mouth or buccal
cavity.
 
                                      G-2
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                         INDEX TO FINANCIAL STATEMENTS
 
<TABLE>
<CAPTION>
                                                                                                         PAGE
                                                                                                     -------------
<S>                                                                                                  <C>
Report of Independent Accountants..................................................................       F-2
Balance Sheets.....................................................................................       F-3
Statements of Operations...........................................................................       F-4
Statements of Stockholders' Deficit................................................................       F-5
Statements of Cash Flows...........................................................................       F-6
Notes to Financial Statements......................................................................   F-7 to F-16
</TABLE>
 
                                      F-1
<PAGE>
                       REPORT OF INDEPENDENT ACCOUNTANTS
 
To the Board of Directors and Stockholders
Pharmavene, Inc.
 
    We  have  audited the  accompanying balance  sheets  of Pharmavene,  Inc. (A
Development Stage Enterprise) as of December 31, 1994 and 1995, and the  related
statements  of operations, stockholders' deficit, and cash flows for each of the
three years in the period ended December  31, 1995, and for the period  February
16,  1990 (date of  inception) to December 31,  1995. These financial statements
are the responsibility  of the  Company's management. Our  responsibility is  to
express an opinion on these financial statements based on our audits.
 
    We  conducted  our audits  in  accordance with  generally  accepted auditing
standards. Those standards require that we plan and perform the audit to  obtain
reasonable assurance about whether the financial statements are free of material
misstatement.  An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statements. An audit also  includes
assessing  the  accounting principles  used  and significant  estimates  made by
management, as well as evaluating the overall financial statement  presentation.
We believe that our audits provide a reasonable basis for our opinion.
 
    In  our opinion, the financial statements  referred to above present fairly,
in all material respects, the financial  position of the Company as of  December
31, 1994 and 1995, and the results of its operations and its cash flows for each
of  the three years  in the period ended  December 31, 1995,  and for the period
February 16, 1990 (date  of inception) to December  31, 1995 in conformity  with
generally accepted accounting principles.
 
                                          COOPERS & LYBRAND L.L.P.
Rockville, Maryland
January 24, 1996
 (except as to the information presented in Note 11,
 for which the date is March 14, 1996)
 
                                      F-2
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                                 BALANCE SHEETS
                                     ASSETS
 
<TABLE>
<CAPTION>
                                                                      DECEMBER 31,
                                                              ----------------------------
                                                                  1994           1995
                                                              -------------  -------------    MARCH 31,      PRO FORMA
                                                                                                1996         MARCH 31,
                                                                                            -------------      1996
                                                                                             (UNAUDITED)   -------------
                                                                                                            (UNAUDITED)
<S>                                                           <C>            <C>            <C>            <C>
Current assets:
  Cash and cash equivalents.................................  $   1,045,248  $     408,166  $     586,368  $   2,589,794
  Grant and other receivables...............................         19,557            721            734            734
  Prepaid expenses..........................................         54,594        171,266        863,256        152,656
                                                              -------------  -------------  -------------  -------------
    Total current assets....................................      1,119,399        580,153      1,450,358      2,743,184
Property and equipment, net.................................        564,748      1,563,215      1,582,112      1,582,112
Other assets................................................         53,004        469,158        769,964        576,164
                                                              -------------  -------------  -------------  -------------
      Total assets..........................................  $   1,737,151  $   2,612,526  $   3,802,434  $   4,901,460
                                                              -------------  -------------  -------------  -------------
                                                              -------------  -------------  -------------  -------------
 
                                         LIABILITIES AND STOCKHOLDERS' DEFICIT
 
Current liabilities:
  Accounts payable and accrued expenses.....................  $   1,114,474  $     964,089  $   1,215,832  $   1,215,832
  Accrued compensation......................................        265,230        210,520         76,500         76,500
  Obligation under capital leases...........................        209,710        360,277        383,441        383,441
  Convertible notes payable to investors....................      2,000,000       --             --             --
                                                              -------------  -------------  -------------  -------------
    Total current liabilities...............................      3,589,414      1,534,886      1,675,773      1,675,773
                                                              -------------  -------------  -------------  -------------
Convertible notes payable to investors......................       --            7,000,000        938,400       --
Obligation under capital leases, less current portion.......        166,579        748,443        783,960        783,960
                                                              -------------  -------------  -------------  -------------
    Total long-term liabilities.............................        166,579      7,748,443      1,722,360        783,960
                                                              -------------  -------------  -------------  -------------
Commitments and contingencies
Mandatorily Redeemable Series A Convertible Preferred Stock,
 $.01 par value; designated 14,739,004, 17,489,001 and
 27,385,664 (Unaudited) shares at December 31, 1994 and 1995
 and March 31, 1996; issued and outstanding 14,697,337,
 16,297,334 and 25,363,997 (Unaudited) shares at December
 31, 1994 and 1995 and March 31, 1996, (liquidation
 preference of $21,000,000 and $30,600,000 (Unaudited) at
 December 31, 1995 and March 31, 1996; redemption value of
 original purchase price plus any declared but unpaid
 dividends).................................................     14,697,337     16,697,333     24,697,332       --
                                                              -------------  -------------  -------------  -------------
Stockholders' (deficit) equity:
  Preferred stock, $.01 par value; authorized 30,100,000
   shares of which 14,739,004 17,489,001 and 27,385,664
   (Unaudited) shares at December 31, 1994 and 1995 and
   March 31, 1996, respectively, have been designated as
   Series A Convertible Preferred Stock.....................       --             --             --             --
  Common stock, $0.01 par value; authorized 25,000,000
   shares; issued and outstanding, 241,741, 288,980 and
   289,514 (Unaudited) shares at December 31, 1994 and 1995
   and March 31, 1996, respectively and 6,472,332 shares pro
   forma at March 31, 1996 (Unaudited)......................          2,418          2,890          2,895         64,724
  Paid-in capital...........................................        811,096        837,885      5,200,280     35,071,209
  Deficit accumulated during the development stage..........    (17,529,693)   (24,208,911)   (29,496,206)   (32,694,206)
                                                              -------------  -------------  -------------  -------------
    Total stockholders' (deficit) equity....................    (16,716,179)   (23,368,136)   (24,293,031)     2,441,727
                                                              -------------  -------------  -------------  -------------
      Total liabilities and stockholders' (deficit)
       equity...............................................  $   1,737,151  $   2,612,526  $   3,802,434  $   4,901,460
                                                              -------------  -------------  -------------  -------------
                                                              -------------  -------------  -------------  -------------
</TABLE>
 
   The accompanying notes are an integral part of these financial statements.
 
                                      F-3
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                            STATEMENTS OF OPERATIONS
 
<TABLE>
<CAPTION>
                                                                                                             CUMULATIVE FOR
                                                                                                               THE PERIOD
                                                                  FOR THE PERIOD                              FEBRUARY 16,
                                                                 FEBRUARY 16, 1990         FOR THE                1990
                                    FOR THE YEARS ENDED              (DATE OF         THREE MONTHS ENDED        (DATE OF
                                        DECEMBER 31,                INCEPTION)            MARCH 31,            INCEPTION)
                             ----------------------------------   TO DECEMBER 31,   ----------------------    TO MARCH 31,
                                1993        1994        1995           1995            1995        1996           1996
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
<S>                          <C>         <C>         <C>         <C>                <C>         <C>         <C>
                                                                                    (UNAUDITED) (UNAUDITED)   (UNAUDITED)
Revenues:
  Licensing revenue........  $   --      $2,000,000  $   --        $   2,000,000    $   --      $   --        $  2,000,000
  Research and development
   revenue.................      --          --         111,384          111,384        95,284      18,907         130,291
  Research and development
   grants..................     268,891     193,860      --              512,751        --          --             512,751
  Interest income..........      19,596      45,983      34,410          190,611         4,502       9,638         200,249
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
    Total revenues.........     288,487   2,239,843     145,794        2,814,746        99,786      28,545       2,843,291
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
Expenses:
  Research and
   development.............   3,932,133   4,935,641   4,986,538       19,131,095     1,230,045   1,266,187      20,397,282
  General and
   administrative..........   1,413,258   1,317,280   1,392,409        6,298,930       368,829     477,908       6,776,838
  Interest expense.........     425,867     131,904     446,065        1,593,632        58,047   3,571,745       5,165,377
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
    Total expenses.........   5,771,258   6,384,825   6,825,012       27,023,657     1,656,921   5,315,840      32,339,497
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
Net loss...................  $(5,482,771) $(4,144,982) $(6,679,218)   $ (24,208,911) $(1,557,135) $(5,287,295)   $(29,496,206)
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
Net loss per common and
 common share equivalent...  $    (1.59) $    (1.20) $    (1.91)   $       (7.19)   $    (0.45) $    (1.51)   $      (8.76)
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
Weighted average common
 shares and common share
 equivalents outstanding...   3,455,473   3,457,896   3,495,333        3,365,949     3,466,028   3,507,700       3,365,962
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
                             ----------  ----------  ----------  -----------------  ----------  ----------  ----------------
</TABLE>
 
   The accompanying notes are an integral part of these financial statements.
 
                                      F-4
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                      STATEMENTS OF STOCKHOLDERS' DEFICIT
 
<TABLE>
<CAPTION>
                                                                                             DEFICIT
                                                                                           ACCUMULATED
                                                            COMMON STOCK                    DURING THE
                                                       ----------------------   PAID-IN    DEVELOPMENT
                                                        SHARES      AMOUNT      CAPITAL       STAGE         TOTAL
                                                       ---------  -----------  ----------  ------------  -----------
<S>                                                    <C>        <C>          <C>         <C>           <C>
Net loss for the period February 16, 1990 (date of
 inception) to December 31, 1990.....................     --       $  --       $   --       $ (657,757)  $  (657,757)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, December 31, 1990...........................     --          --           --         (657,757)     (657,757)
Initial sale of common stock, $0.06 per share........     48,990         490        2,449       --             2,939
Common stock options exercised.......................     11,595         116          580       --               696
Sale of Series A Preferred warrants..................     --          --            3,000       --             3,000
Net loss.............................................     --          --           --       (2,141,789)   (2,141,789)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, December 31, 1991...........................     60,585         606        6,029   (2,799,546)   (2,792,911)
Common stock options exercised, $0.06-$2.88 per
 share...............................................      8,799          88          440       --               528
Interest ascribed to common stock warrants in
 connection with debt financing......................     --          --          500,569       --           500,569
Exercise of common stock warrants issued in
 connection with debt financing, $0.06 per share.....    166,670       1,667        8,333       --            10,000
Net loss.............................................     --          --           --       (5,102,394)   (5,102,394)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, December 31, 1992...........................    236,054       2,361      515,371   (7,901,940)   (7,384,208)
Common stock options exercised, $0.06-$5.70 per
 share...............................................      1,778          18          479       --               497
Interest ascribed to common stock warrants in
 connection with debt financing......................     --          --          292,268       --           292,268
Net loss.............................................     --          --           --       (5,482,771)   (5,482,771)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, December 31, 1993...........................    237,832       2,379      808,118  (13,384,711)  (12,574,214)
Common stock options exercised, $0.06-$5.70 per
 share...............................................      1,371          14        2,851       --             2,865
Exercise of common stock warrants issued in
 connection with debt financing, $0.06 per share.....      2,538          25          127       --               152
Net loss.............................................     --          --           --       (4,144,982)   (4,144,982)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, December 31, 1994...........................    241,741       2,418      811,096  (17,529,693)  (16,716,179)
Common stock options exercised, $0.06-$4.50 per
 share...............................................     47,239         472       26,789       --            27,261
Net loss.............................................     --          --           --       (6,679,218)   (6,679,218)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, December 31, 1995...........................    288,980       2,890      837,885  (24,208,911)  (23,368,136)
Common stock options exercised, $4.50 per share
 (Unaudited).........................................        534           5        2,395       --             2,400
Interest ascribed to common stock in connection with
 debt conversion (Unaudited).........................     --          --        3,325,000       --         3,325,000
Interest ascribed to common stock warrants issued in
 connection with debt financing, $0.75 per share
 (Unaudited).........................................     --          --          969,000       --           969,000
Interest ascribed to common stock warrants issued in
 connection with draw of $1 million of debt
 financing, $0.75 per share (Unaudited)..............     --          --           66,000       --            66,000
Net loss (Unaudited).................................     --          --           --       (5,287,295)   (5,287,295)
                                                       ---------  -----------  ----------  ------------  -----------
Balance, March 31, 1996 (Unaudited)..................    289,514       2,895    5,200,280  (29,496,206)  (24,293,031)
Pro forma conversion of Mandatorily Redeemable Series
 A Convertible Preferred Stock (Note 12)
 (Unaudited).........................................  5,636,452      56,365   24,640,968       --        24,697,333
Pro forma conversion of convertible notes payable
 drawn under the March 1996 credit agreement (Note
 12) (Unaudited).....................................    545,455       5,455    2,994,545       --         3,000,000
Pro forma interest ascribed to common stock in
 connection with debt conversion (Unaudited).........     --          --        2,100,000   (2,100,000)      --
Pro forma interest ascribed to common stock warrants
 issued in connection with draw of $2 million of debt
 financing, $0.75 per share (Unaudited)..............     --          --          132,000     (132,000)      --
Pro forma common stock options exercised, $0.60-$4.50
 per share (Note 12) (Unaudited).....................        911           9        3,416       --             3,425
Pro forma net loss, balance of interest ascribed to
 common stock $904,400 and $61,600 amortized over the
 term of the agreement (Unaudited)...................     --          --           --         (966,000)     (966,000)
                                                       ---------  -----------  ----------  ------------  -----------
Pro forma Balance, March 31, 1996 (Note 12)
 (Unaudited).........................................  6,472,332   $  64,724   $35,071,209 ($32,694,206) $ 2,441,727
                                                       ---------  -----------  ----------  ------------  -----------
                                                       ---------  -----------  ----------  ------------  -----------
</TABLE>
 
   The accompanying notes are an integral part of these financial statements.
 
                                      F-5
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                            STATEMENTS OF CASH FLOWS
 
<TABLE>
<CAPTION>
                                                                                                                CUMULATIVE
                                                                           FOR THE                               FOR THE
                                                                            PERIOD                                PERIOD
                                                                         FEBRUARY 16,                          FEBRUARY 16,
                                                                          1990 (DATE                            1990 (DATE
                                                  FOR THE                     OF        FOR THE THREE MONTHS        OF
                                          YEARS ENDED DECEMBER 31,        INCEPTION)      ENDED MARCH 31,       INCEPTION)
                                     ----------------------------------  TO DECEMBER   ----------------------  TO MARCH 31,
                                        1993        1994        1995       31, 1995       1995        1996         1996
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
<S>                                  <C>         <C>         <C>         <C>           <C>         <C>         <C>
                                                                                       (UNAUDITED) (UNAUDITED) (UNAUDITED)
Cash flows from operating
 activities:
  Net loss.........................  $(5,482,771) $(4,144,982) $(6,679,218) ($24,208,911) $(1,557,135) $(5,287,295) ($29,496,206)
  Adjustments to reconcile net loss
   to net cash used in operating
   activities:
    Depreciation and
     amortization..................     211,329     282,220     416,190    1,075,635       78,841     135,980    1,211,615
    Interest expense ascribed to
     common stock warrants.........     292,268      --          --          792,837       --       3,394,000    4,186,837
    Gain on sale of assets.........      --          --         (85,081)     (85,081)      --          --          (85,081)
    Increase (decrease) in cash due
     to changes in assets and
     liabilities:
      Grant and other
       receivables.................    (111,582)     92,384      18,836         (721)      10,226         (13)        (734)
      Prepaid expenses.............       5,009      (5,316)   (116,672)    (171,266)     (36,323)   (691,990)    (863,256)
      Other assets.................      (4,331)        649    (416,154)    (469,158)      (5,644)   (300,806)    (769,964)
      Accounts payable and accrued
       expenses....................     173,868     493,289    (378,885)     735,589     (319,393)    226,243      961,832
      Accrued compensation.........      93,952      55,230     (54,710)     210,520     (140,592)   (134,020)      76,500
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
      Net cash used in operating
       activities..................  (4,822,258) (3,226,526) (7,295,694) (22,120,556)  (1,970,020) (2,657,901) (24,778,457)
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
Cash flows from investing
 activities:
  Capital expenditures.............     (61,762)    (44,335)   (417,421)    (863,163)     (21,574)     (2,364)    (865,527)
  Proceeds from sale of
   equipment.......................      --          --         139,845      140,807       --          --          140,807
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
      Net cash used in investing
       activities..................     (61,762)    (44,335)   (277,576)    (722,356)     (21,574)     (2,364)    (724,720)
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
Cash flows from financing
 activities:
  Proceeds from sale of Series A
   Convertible Preferred Stock.....   7,675,001   1,324,999   1,999,996   16,697,333       --       7,999,999   24,697,332
  Proceeds from sale of warrants...      --          --          --            3,000       --          --            3,000
  Proceeds from issuance of common
   stock...........................         497       3,017      27,261       44,938       25,925     968,400    1,013,338
  Proceeds from promissory notes...   1,315,164   2,000,000   8,900,000   15,133,165    1,215,000   1,938,400   17,071,565
  Repayment of promissory notes....  (3,315,165)     --      (3,900,000)  (8,133,165)      --      (8,000,000) (16,133,165)
  Initial public offering costs
   financed by accounts payable....      --          --         228,500      228,500       --          25,500      254,000
  Principal payments under capital
   lease obligations...............    (134,257)   (198,450)   (319,569)    (722,693)     (56,025)    (93,832)    (816,525)
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
      Net cash provided by
       financing activities........   5,541,240   3,129,566   6,936,188   23,251,078    1,184,900   2,838,467   26,089,545
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
Net increase (decrease) in cash and
 cash equivalents..................     657,220    (141,295)   (637,082)     408,166     (806,694)    178,202      586,368
Cash and cash equivalents at the
 beginning of the period...........     529,323   1,186,543   1,045,248       --        1,045,249     408,166       --
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
Cash and cash equivalents at the
 end of the period.................  $1,186,543  $1,045,248  $  408,166   $  408,166   $  238,555  $  586,368   $  586,368
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
Supplemental disclosures of cash
 flow information:
  Cash paid during the period for
   interest........................  $  116,060  $  131,903  $  446,065   $  800,796   $   58,047  $  177,745   $  978,541
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
  Noncash financing activities:
    Capital lease obligations
     incurred to acquire
     equipment.....................  $  208,603  $  187,746  $1,051,999   $1,831,413   $  148,450  $  152,513   $1,983,925
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
                                     ----------  ----------  ----------  ------------  ----------  ----------  ------------
</TABLE>
 
   The accompanying notes are an integral part of these financial statements.
 
                                      F-6
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                         NOTES TO FINANCIAL STATEMENTS
 
1.  ORGANIZATION AND FINANCING
 
    ORGANIZATION
 
    Pharmavene,  Inc.  (the  "Company")  is  a  Delaware  corporation  which was
originally incorporated on December 22,  1989 as Substance Abuse Sciences,  Inc.
On  February 16, 1990,  the Company amended its  Certificate of Incorporation to
change its name to Pharmavene, Inc. The Company develops pharmaceutical products
utilizing advanced drug delivery systems.
 
    The Company is considered to be a development stage enterprise as it has not
derived significant revenues from its planned principal operations.
 
    FINANCING REQUIREMENTS
 
    In the  course of  its  development activities,  the Company  has  sustained
continuing  operating  losses  and  expects  such  losses  to  continue  for the
foreseeable future. As of  December 31, 1995,  the Company is  in a net  working
capital  deficit position. The Company's future capital requirements will depend
on many  factors, including  the  progress of  the Company's  collaborative  and
independent   research  and   development  programs,   payments  received  under
collaborative agreements with other companies, if any, the results and costs  of
preclinical   and  clinical  testing  for  the  Company's  products,  the  costs
associated with and the timing of regulatory approvals, technological  advances,
the  status of competitive products and  the commercial success of the Company's
products. The Company plans to continue to finance operations with a combination
of stock sales, borrowings, payments from future strategic partnerships and,  in
the  longer  term,  revenues  from  product  sales  and  licensing  and  royalty
arrangements (see Notes 11  and 12). There can  be no assurance that  additional
funds  will be available on a timely basis, on favorable terms or at all or that
such funds, if raised, would be sufficient to permit the Company to continue  to
conduct   its  operations  or  that  the  Company's  planned  products  will  be
commercially successful.
 
    SPLIT OF COMMON STOCK
 
    In March 1996, the Board of Directors authorized: (i) a one-for-six  reverse
split of the outstanding shares of the Company's common stock, and (ii) a change
in  the number of authorized shares of  common and preferred stock to 25,000,000
and 30,100,000, respectively. All references to common stock, options, warrants,
per share data and the conversion rates of Series A Convertible Preferred  Stock
and Convertible Notes have been restated to give effect to the reverse split.
 
    REGISTRATION STATEMENT
 
    In  October  1995,  the  Board  of  Directors  authorized  the  filing  of a
registration statement (the  "Registration Statement") with  the Securities  and
Exchange  Commission for the initial public  offering (the "Offering") of shares
of the Company's common stock.
 
2.  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
 
    BASIS OF ACCOUNTING
 
    The Company is  complying with Statement  of Financial Accounting  Standards
No.   7,  which   prescribes  reporting   requirements  for   development  stage
enterprises.
 
    USE OF ESTIMATES
 
    The  preparation  of  financial  statements  in  conformity  with  generally
accepted  accounting  principles  requires  management  to  make  estimates  and
assumptions that  affect the  reported  amounts of  assets and  liabilities  and
disclosure  of contingent  assets and liabilities  at the date  of the financial
statements and  the  reported  amounts  of  revenues  and  expenses  during  the
reporting period. Actual results could differ from those estimates.
 
                                      F-7
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
2.  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)
    DEPRECIATION AND AMORTIZATION
 
    Equipment  is  recorded at  cost.  Depreciation of  laboratory  and computer
equipment is computed on  the straight-line method  based upon estimated  useful
lives  ranging from three to seven years. Equipment held under capital leases is
amortized using the straight-line method over  the terms of the leases or  their
estimated   useful  lives,  whichever  is  shorter.  Amortization  of  leasehold
improvements is computed on the straight-line method based on the shorter of the
estimated useful life of the improvement or the remaining term of the lease.
 
    HISTORICAL NET LOSS PER SHARE
 
    Historical net loss per common share is based on the weighted average number
of  common  shares  outstanding  during  the  periods  presented.  Pursuant   to
Securities  and Exchange Commission Staff Acounting  Bulletin No. 83, all common
shares, Convertible Preferred  Stock and  Convertible Notes  Payable issued  and
stock  options and warrants granted by the Company during the 12 months prior to
the date of the Registration Statement have been included in the calculation  of
weighted  average common shares  and common share  equivalents outstanding as if
they were outstanding for all periods presented. Convertible Preferred Stock and
Convertible Notes Payable issued and stock  options and warrants granted by  the
Company  prior to the  aforementioned 12-month period have  not been included in
the calculation because such items were antidilutive.
 
    REVENUE RECOGNITION
 
    The Company has entered into  a license agreement with Rhone-Poulenc  Rorer,
Inc.,  as  described in  Note 3  below.  Revenue from  the license  agreement is
recognized in  accordance  with  the terms  of  the  agreement.  Non-refundable,
non-creditable fees or milestone payments are recognized when they are earned in
accordance with the performance requirements and contractual terms. Research and
development  grant revenues are recognized over  the period of performance under
the terms of the related agreements.
 
    CASH AND CASH EQUIVALENTS
 
    The Company  considers  all  highly  liquid  investments  with  an  original
maturity  of  three  months  or less  at  the  date of  acquisition  to  be cash
equivalents. The Company's policy regarding  investments, pending their use,  is
to   ensure  safety,  liquidity  and  capital  preservation  while  obtaining  a
reasonable rate of return.
 
    CONCENTRATION OF CREDIT RISK
 
    The Company  has invested  its excess  cash in  a money  market account  and
certificates  of  deposit  with  two  commercial  banks.  The  Company  has  not
experienced any losses on its investments.
 
    INCOME TAXES
 
    Deferred income  taxes are  recognized for  the tax  consequences in  future
years  for differences between the tax bases of assets and liabilities and their
financial reporting  amounts at  each year  end based  on enacted  tax laws  and
statutory  tax  rates applicable  to the  periods in  which the  differences are
expected to affect  taxable income.  Valuation allowances  are established  when
necessary  to reduce deferred tax assets to  the amount expected to be realized.
Income tax expense is the tax payable  for the period and the change during  the
period in deferred tax assets and liabilities.
 
    PATENT COSTS
 
    As a result of research and development efforts conducted by the Company, it
has received and applied for, and is in the process of applying for, a number of
patents  to protect  proprietary inventions.  Costs incurred  in connection with
patent applications have been expensed as incurred and are reflected as  general
and administrative expenses.
 
                                      F-8
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
2.  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)
    RECENT ACCOUNTING PRONOUNCEMENTS
 
    The  Company must adopt Statement of Financial Accounting Standards No. 121,
Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets  to
be  Disposed Of, commencing in fiscal year 1996. Management believes adoption of
this standard  will  not have  a  material  impact on  the  Company's  financial
statements.
 
    The  Company  does  not  intend  to adopt  the  provisions  of  Statement of
Financial Accounting Standards No. 123, Accounting for Stock-Based Compensation,
as they  pertain  to financial  statement  recognition of  compensation  expense
attributable to option grants.
 
3.  LICENSE AGREEMENT
    In   August  1994,  the  Company  entered  into  a  license  agreement  with
Rhone-Poulenc Rorer, Inc.  ("RPR") under which  the Company granted  to RPR  the
exclusive worldwide right to develop, manufacture and market products containing
the  Company's  proprietary Butyrylcholinesterase  (BChE)  technology, resulting
from know-how and patent rights owned by the Company.
 
    Under the agreement, RPR paid  the Company a non-refundable,  non-creditable
license  fee of $2,000,000  in August 1994,  and is obligated  to make milestone
payments and royalty payments on product sales over the longer of the life of an
issued patent  or  15  years.  Additionally, during  the  period  of  technology
transfer,  RPR  will reimburse  the Company  for certain  costs incurred  by the
Company in  the  furtherance of  the  development  of the  BChE  technology  and
preparation  of filings  with U.S.  and foreign  government regulatory agencies.
During 1995 the  Company was  reimbursed $111,384  by RPR  under the  agreement,
which amount is recorded as research and development revenue.
 
4.  PROPERTY AND EQUIPMENT
    Property  and  equipment  at December  31,  1994  and 1995  consists  of the
following:
 
<TABLE>
<CAPTION>
                                                                                  1994          1995
                                                                              ------------  ------------
<S>                                                                           <C>           <C>
Laboratory and office equipment.............................................  $    875,402  $  1,770,836
Leasehold improvements......................................................       160,442       369,565
Computer equipment..........................................................       188,350       328,702
                                                                              ------------  ------------
    Total cost..............................................................     1,224,194     2,469,103
Less accumulated depreciation and amortization..............................      (659,446)     (905,888)
                                                                              ------------  ------------
                                                                              $    564,748  $  1,563,215
                                                                              ------------  ------------
                                                                              ------------  ------------
</TABLE>
 
5.  CAPITAL STRUCTURE
 
    MANDATORILY REDEEMABLE SERIES A CONVERTIBLE PREFERRED STOCK
 
    Under the Convertible Preferred Stock  and Warrant Purchase Agreement  dated
as  of January 31, 1991 (the  "Purchase Agreement"), the Company was capitalized
in the amount of  $2,000,000 through the  sale of 2,000,000  shares of Series  A
Convertible  Preferred Stock to an investor (the "Investor"). In connection with
the Purchase  Agreement, the  Company  also sold  to  the Investor  warrants  to
purchase  up to  3,000,000 additional shares  of Series  A Convertible Preferred
Stock at $1.00 per share, subject to adjustment.
 
    On September 18, 1991, the Investor transferred to two additional  investors
(collectively  the "Investors") warrants to purchase  550,000 shares of Series A
Convertible Preferred Stock. Contemporaneously with this transfer, the Investors
exercised  warrants  to  purchase  1,700,000  shares  of  Series  A  Convertible
Preferred Stock. Warrants to purchase the remaining 1,300,000 shares of Series A
Convertible Preferred Stock lapsed in January 1994.
 
                                      F-9
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
5.  CAPITAL STRUCTURE (CONTINUED)
    On  April 8, 1992  and May 14,  1992, the Company  sold 1,300,000 shares and
697,337 shares, respectively, of Series A Convertible Preferred Stock to certain
investors for $1.00 per share.
 
    On June 1, 1993,  the Company entered into  the Convertible Preferred  Stock
Purchase  Agreement (the "June 1, 1993 Preferred Agreement") whereby the Company
sold to the Investors and  certain other investors (collectively the  "Preferred
Investors")  5,025,000 shares of Series A  Convertible Preferred Stock for $1.00
per share. Of the proceeds, $3,351,616  was used to repay principal and  accrued
interest  thereon in connection with the  credit agreements discussed in Note 7.
On September 10, 1993, November 24, 1993 and February 24, 1994, the Company sold
1,325,001, 1,325,000  and  1,324,999  shares,  respectively,  of  the  Series  A
Convertible  Preferred  Stock for  $1.00 per  share  to the  Preferred Investors
pursuant to the terms of the Preferred Agreement.
 
    Shares of the Series  A Convertible Preferred Stock  are convertible at  the
option of the holder at any time into shares of common stock of the Company at a
conversion  rate,  subject  to  certain antidilutive  adjustments,  of  four and
one-half shares of Series A Convertible Preferred Stock for one share of  common
stock  at  December  31,  1995.  The Series  A  Convertible  Preferred  Stock is
redeemable at the option  of the holder  at a redemption  value of the  original
purchase  price plus any  declared but unpaid dividends.  No dividends have been
declared.  In  addition,  the  Series  A  Convertible  Preferred  Stock  has   a
liquidation  preference equal to its original  purchase price plus 10% per annum
for each  share from  its original  issue  date, plus  any declared  but  unpaid
dividends.
 
    Holders   of   Series  A   Convertible   Preferred  Stock   (the  "Preferred
Stockholders") vote together with the  common stockholders on most matters.  The
approval  of  a super  majority of  the Preferred  Stockholders is  required for
certain significant transactions. The  Preferred Stockholders fully  participate
in  any dividends  declared and have  the exclusive  right to elect  all but one
member  of  the  Company's  Board  of  Directors.  In  addition,  the  Preferred
Stockholders  have the right of first refusal in the event of sale of any equity
securities of the Company, except for certain excluded security transactions.
 
    If the Company  offers any of  its securities to  the public, the  Preferred
Stockholders have the option to have their common stock received upon conversion
of  their  Series A  Convertible Preferred  Stock included  in the  offering. In
addition, the Preferred Stockholders have the  right to demand that the  Company
register  the common stock received upon  conversion of the Series A Convertible
Preferred Stock.
 
    WARRANTS
 
    In connection with a certain credit agreement executed in 1992 (see Note 7),
the Company issued to the lenders warrants to purchase a total of 277,778 shares
of common stock, exercisable at $.06 per share. Warrants to purchase a total  of
168,320  shares  have  been exercised,  and  the remaining  109,458  warrants at
December 31, 1995 are exercisable through March 15, 2003.
 
    In connection with  a certain  1993 credit agreement  (see Note  7), and  as
amended  and restated by the Preferred Agreement, the Company issued warrants to
one of the lenders to purchase  41,667 shares of Series A Convertible  Preferred
Stock  at $1.00 per share, all of which are outstanding and exercisable. Certain
of the lenders also received warrants to purchase 1,685 shares of the  Company's
common  stock at $.06 per share. Warrants to purchase 880 shares of common stock
were exercised and the remaining  805 warrants are outstanding. All  outstanding
warrants  issued in connection  with the 1993  credit agreements are exercisable
through June 30, 2003.
 
    At the dates the 1992 and 1993 warrants were issued, the Company's Board  of
Directors  had valued the Company's  common stock at $2.88  and $5.70 per share,
respectively. Because the common stock warrants
 
                                      F-10
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
5.  CAPITAL STRUCTURE (CONTINUED)
were issued at an  exercise price below their  estimated fair market value,  the
Company recognized non-cash charges of $500,569 and $292,268 as interest expense
and a corresponding increase to additional paid-in capital during 1992 and 1993,
respectively.
 
    In  connection  with the  May 3,  1994  credit agreement  (see Note  7), the
Company issued  to  the  lenders  warrants to  purchase  33,334  shares  of  the
Company's  common stock, exercisable  at $10.80 per  share. The warrants contain
certain antidilutive  provisions that  adjust their  exercise price  should  the
Company  subsequently issue  common shares or  equivalents at a  price per share
below $10.80. Warrants covered by this agreement expire May 3, 2004.
 
    In connection  with the  May 22,  1995 Credit  Agreement (see  Note 7),  the
Company  issued  to the  lenders warrants  to purchase  1,150,000 shares  of the
Company's Series A Convertible Preferred Stock, exercisable at $0.96 per  share.
Warrants covered by this agreement expire in May 2005.
 
    In  connection with the October 1995  financial commitment (see Note 7), the
Company agreed to issue warrants to  purchase 50,000 shares of its common  stock
exercisable  at the  initial public  offering price per  share. In  the event an
initial public offering is not completed by April 30, 1996, the warrant price is
to be set  at the  fair value  as determined by  the Board  of Directors.  These
warrants are exercisable immediately and expire in October 2005.
 
    The  Company has reserved a sufficient number  of shares of its common stock
to effect  conversion of  its convertible  securities and  the exercise  of  its
options and warrants outstanding and available for issuance.
 
6.  COMMON STOCK OPTIONS
    In  1991, the  Board of  Directors adopted the  1991 Stock  Option Plan (the
"Plan"), which, as amended, provides for the granting of options to purchase  up
to  1,400,000 shares of the Company's common stock to employees and consultants.
Common stock option activity under this plan is as follows:
 
<TABLE>
<CAPTION>
                                                                   NUMBER     EXERCISE PRICE
                                                                 OF SHARES      PER SHARE
                                                                 ----------  ----------------
<S>                                                              <C>         <C>
Balance, December 31, 1992.....................................     108,451  $   .06 - $ 2.88
  Granted......................................................     253,909            $ 5.70
  Exercised....................................................      (1,778) $   .06 - $  .60
  Canceled.....................................................      (4,000) $   .06 - $ 5.70
                                                                 ----------
Balance, December 31, 1993.....................................     356,582  $   .06 - $ 5.70
  Granted......................................................      53,333  $  4.50 - $10.80
  Exercised....................................................      (1,371) $   .30 - $ 5.70
  Canceled.....................................................     (38,555) $   .06 - $10.80
                                                                 ----------
Balance, December 31, 1994.....................................     369,989  $   .06 - $ 4.50
  Granted......................................................     256,522            $ 4.50
  Exercised....................................................     (47,239) $   .06 - $ 4.50
  Cancelled....................................................        (201)           $ 4.50
                                                                 ----------
Balance, December 31, 1995.....................................     579,071  $   .06 - $ 4.50
                                                                 ----------
                                                                 ----------
</TABLE>
 
    Common stock options normally vest over a two, four and five year period. At
December 31,  1995, 151,419  stock options  were exercisable  and 750,133  stock
options  were available for grant. The stock option price is periodically set by
the Compensation Committee of the Board of Directors based upon an evaluation of
the fair market value of the Company's common stock. The Company has issued  its
stock  options at an exercise  price commensurate with the  fair market value of
the Company's common stock on the date of
 
                                      F-11
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
6.  COMMON STOCK OPTIONS (CONTINUED)
grant; accordingly, no compensation costs have been charged to the Statements of
Operations for these  stock option  grants. The Compensation  Committee may,  in
connection  with the grant of any option under the Plan, grant to the optionee a
stock appreciation right. No such rights have been granted.
 
    Common stock options covering 260,251 shares  granted at $5.70 per share  in
1993,  and at $10.80 per share  in 1994 were repriced at  $4.50 per share by the
Board of  Directors,  based upon  the  evaluation of  the  market value  of  the
Company's common stock as of October 18, 1994.
 
7.  CREDIT AGREEMENTS
 
    1992 AND 1993 AGREEMENTS
 
    The  Company entered into credit agreements in 1992 and 1993 with certain of
the investors to  finance short-term working  capital requirements. All  amounts
borrowed   under  the  credit  agreements,  totaling  $3,315,165,  inclusive  of
interest, were repaid from proceeds of the June 1, 1993 Preferred Agreement.
 
    MAY 1994 AGREEMENT
 
    The Company entered into a credit  agreement dated May 3, 1994 with  certain
of  its investors  which provided that  the Company could  borrow, under certain
conditions, up to $4,395,000 at an interest rate of 7 1/4%. The amount  borrowed
under  the credit agreement was due the earlier of one year from the date of the
first draw, or upon closing if the Company raises $10,000,000 or more through an
equity offering or is sold  or merges. In connection  with the execution of  the
credit  agreement, the  Company agreed to  issue warrants to  purchase shares of
common stock at $10.80 per share, exercisable  at one share of common stock  for
every  $60 of actual borrowings. The Company  borrowed $1,000,000 on each of May
23, 1994 and  August 4,  1994 under  the terms of  the credit  agreement and  in
connection  therewith 33,334  common stock  warrants were  issued and  are fully
exercisable at December 31, 1995. The warrants expire May 3, 2004. In May  1995,
investors  under the May 3, 1994  Credit Agreement converted loans of $2,000,000
into Series A Preferred Stock at $1.25 per share, adjustable to $0.75 per  share
in  the event  the Company  does not  complete a  corporate equity  financing or
licensing transaction of $15,000,000 or more  or a merger or acquisition of  the
Company  before  December  31,  1995,  or  an  initial  public  offering  of its
securities by February 28, 1996.
 
    MAY 1995 AGREEMENT
 
    The Company entered into a credit agreement dated May 22, 1995 with  certain
of  its  investors which  provides that  the Company  may borrow,  under certain
conditions, up to $8,000,000 at an interest rate of 9%. The loan is due  January
15,  1997, and  is convertible in  the event of  a merger or  acquisition of the
Company into Series A Preferred Stock at $1.25 per share, or in the event of  an
initial  public offering, into shares of the  Company's common stock at the rate
of one-half of the price per share in an initial public offering. In  connection
with  the execution of the credit agreement  and the funding of $7,000,000 loans
thereunder, as of December 31, 1995,  the Company has issued 1,150,000  warrants
to  the investors to purchase shares of Series A Preferred Stock, at an exercise
price of $0.96 per share, and  is committed to issue 50,000 additional  warrants
based upon actual funding of loans at the rate of one warrant for each $20.00 of
actual borrowing. The warrants expire in May 2005. See Note 11.
 
    OCTOBER 1995 COMMITMENT
 
    In  October 1995,  the Company  entered into  an agreement  with two  of its
investors to provide  up to $3,000,000  on terms to  be negotiated. This  credit
commitment was replaced by the 1996 Credit Agreement (see Note 11).
 
    Interest  expense for the years ended December  31, 1993, 1994 and 1995, and
for the period February 16, 1990 (date of inception) to December 31, 1995, under
all  borrowing  arrangements  was  $73,523,  $75,353,  $353,338  and   $540,766,
respectively.
 
                                      F-12
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
8.  INCOME TAXES
    The  components of the Company's net deferred  tax asset and the tax effects
of the primary temporary differences giving  rise to the Company's deferred  tax
asset are as follows at December 31, 1994 and 1995:
 
<TABLE>
<CAPTION>
                                                                1994           1995
                                                            -------------  -------------
<S>                                                         <C>            <C>
Net operating loss carryforwards and credits..............  $   5,387,000   $ 7,578,000
Capitalized start-up costs for tax purposes...............      1,847,000     2,347,000
Other.....................................................         59,000        17,000
                                                            -------------  -------------
Deferred tax asset........................................      7,293,000     9,942,000
Valuation allowance.......................................     (7,293,000)   (9,942,000)
                                                            -------------  -------------
Net deferred tax asset....................................  $    --         $   --
                                                            -------------  -------------
                                                            -------------  -------------
</TABLE>
 
    As  of December 31, 1995,  the Company has the  following net operating loss
carryforwards available for federal income tax purposes:
 
<TABLE>
<CAPTION>
EXPIRATION
- -------------------------------------------------------------------------------
<S>                                                                              <C>
2005...........................................................................  $     313,000
2006...........................................................................      1,259,000
2007...........................................................................      3,818,000
2008...........................................................................      4,403,000
2009...........................................................................      2,834,000
2010...........................................................................      5,375,000
                                                                                 -------------
    Total......................................................................  $  18,002,000
                                                                                 -------------
                                                                                 -------------
</TABLE>
 
    As a result of a greater-than-50%  ownership change in 1993, utilization  of
the net operating loss carryforwards will be limited due to the ownership change
limitations provided by the tax law.
 
9.  PENSION PLAN
    The  Company  offers  a  defined contribution  401(k)  pension  plan  to all
eligible employees. The plan is administered by trustees. Employee contributions
are voluntary and are  determined on an individual  basis with a maximum  annual
amount  equal to  the maximum  allowable under  federal tax  regulations. Highly
compensated employees are  subject to further  limitations and all  participants
are  always fully  vested. There have  been no employer  contributions under the
plan.
 
10. COMMITMENTS AND CONTINGENCIES
 
    FACILITY LEASE
 
    The Company  previously  leased  administrative and  laboratory  space  from
MedImmune,  Inc., a related party, under  a five year sublease arrangement which
was terminated  by  the Company  in  1995.  Total lease  expense  was  $156,560,
$174,155,  $131,016 and $660,179 for the years ended December 31, 1993, 1994 and
1995 and for the period  February 16, 1990 (date  of inception) to December  31,
1995, respectively.
 
    In  January 1995, the Company entered into  a five year lease, commencing in
May 1995 for administrative and  laboratory space in Rockville, Maryland.  Under
the  lease, the  Company is required  to pay  base rent, which  increases 3% per
year, and operating expenses.
 
                                      F-13
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
10. COMMITMENTS AND CONTINGENCIES (CONTINUED)
    The Company's future minimum lease payments under facility operating  leases
at December 31, 1995 are as follows:
 
<TABLE>
<CAPTION>
YEAR ENDING DECEMBER 31,
- --------------------------------------------------------------------------------
<S>                                                                               <C>
1996............................................................................  $    463,000
1997............................................................................       631,000
1998............................................................................       650,000
1999............................................................................       670,000
2000............................................................................       169,000
                                                                                  ------------
    Total Minimum Payments......................................................  $  2,583,000
                                                                                  ------------
                                                                                  ------------
</TABLE>
 
    CAPITAL LEASES
 
    Included  as  assets in  the balance  sheets are  the following  amounts for
capitalized leases as of December 31, 1994 and 1995:
 
<TABLE>
<CAPTION>
                                                                        1994          1995
                                                                     -----------  ------------
<S>                                                                  <C>          <C>
Laboratory and office equipment....................................  $   779,414  $  1,804,730
Less accumulated amortization......................................     (426,333)     (709,008)
                                                                     -----------  ------------
                                                                     $   353,081  $  1,095,722
                                                                     -----------  ------------
                                                                     -----------  ------------
</TABLE>
 
    Future minimum  lease  payments required  under  capitalized leases  are  as
follows:
 
<TABLE>
<CAPTION>
YEAR ENDING DECEMBER 31,
- --------------------------------------------------------------------------------
<S>                                                                               <C>
1996............................................................................  $    449,969
1997............................................................................       400,472
1998............................................................................       295,355
1999............................................................................       207,841
2000............................................................................           827
                                                                                  ------------
Total minimum lease payments....................................................     1,354,464
Less amounts representing interest at 10% to 18%................................      (245,744)
                                                                                  ------------
Present value of net minimum lease payments.....................................  $  1,108,720
                                                                                  ------------
                                                                                  ------------
</TABLE>
 
11. SUBSEQUENT EVENTS
 
    MAY 1994 AGREEMENT
 
    On  February 28,  1996, the  $2,000,000 loan under  the May  31, 1994 Credit
Agreement (see Note 7), which had  previously been converted at $1.25 per  share
into  shares of Series A Convertible Preferred Stock, was adjusted to convert at
a $0.75 per share conversion price and 1,066,663 additional shares were  issued.
As  a result of the adjustment in  the conversion price, the conversion ratio of
all Series A Convertible Preferred Stock  was adjusted from one share of  common
stock  to four shares of  preferred stock to one share  of common stock to three
shares of preferred stock.
 
    MAY 1995 AGREEMENT
 
    On January  10, 1996,  the  Company borrowed  $1,000,000 and  issued  50,000
warrants  to purchase  shares of  Series A  Preferred Stock  under the  May 1995
Credit Agreement. On March 7, 1996, lenders converted all $8,000,000 covered  by
the agreement into Series A Convertible Preferred Stock at a conversion price of
 
                                      F-14
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
11. SUBSEQUENT EVENTS (CONTINUED)
$1.00  per share, which was $0.25 per  share less than the originally negotiated
conversion price. The decrease in the conversion price was an inducement to  the
lenders  to exercise their conversion option and,  as a result, the Company will
record a non-cash expense of $3,325,000 in the first quarter of 1996.
 
    MARCH 1996 AGREEMENTS
 
    The Company  entered  into  two  credit  agreements,  dated  March  7,  1996
(collectively,  the "1996 Credit Agreement") with certain of its investors which
provide that  the Company  may borrow  when  certain conditions  are met  up  to
$7,300,000  at an interest rate of  8 1/2%. The loans are  due May 31, 1997, and
are convertible in  the event of  a merger  or acquisition of  the Company  into
Series  A Convertible Preferred Stock at $1.25 per  share, or in the event of an
initial public offering  at one-half of  the initial public  offering price  per
share.  In connection with the 1996 Credit Agreement, the Company issued 730,000
warrants to the investors at  an exercise price of  $0.75 per share to  purchase
shares of Series A Convertible Preferred Stock and is committed to issue 365,000
additional  warrants  based upon  actual funding  of  loans at  the rate  of one
warrant for each $20.00 of actual borrowing. The warrants expire in March  2006.
On  March 8,  1996, the Company  borrowed $1,000,000 and  issued 50,000 warrants
under the 1996 Credit Agreement.
 
    In connection  with  the 1996  Credit  Agreement, the  Company  ascribed  an
estimated  fair  value  of $969,000  to  the  warrants issued  at  the  time the
agreement was executed, with a like  amount recorded as debt issuance costs.  In
addition, the proceeds of $1,000,000 from the initial draw under the 1996 Credit
Agreement  was allocated  between the  debt of  $934,000 and  the estimated fair
value of the warrants of $66,000. The debt will be written up to its face  value
of $1,000,000 using the effective interest method over the term of the debt. The
debt  issuance costs will  be amortized over  the life of  the agreement. At the
time of the  closing of  the Offering, the  outstanding balance  under the  1996
Credit  Agreement will  be converted  into common  stock and  any remaining debt
discount and debt issuance costs will be expensed.
 
    The $1,000,000 initial draw under  the 1996 Credit Agreement is  mandatorily
convertible into common stock upon closing of the Offering at a conversion price
of one-half of the Offering price. The Company will record a non-cash expense of
$700,000 upon closing of the offering to reflect this discount.
 
    In  connection with the 1996 Credit Agreement, employees of the Company were
issued 194,485 stock options to purchase shares of the Company's common stock at
the greater of $4.50 or 85% of the initial public offering price per share.
 
    SPLIT OF COMMON STOCK
 
    On March 14, 1996,  the Board of Directors  authorized a one-to-six  reverse
split of the outstanding shares of the Company's Common Stock.
 
12. UNAUDITED INFORMATION
 
    BASIS OF PRESENTATION
 
    The  unaudited interim financial  statements have been  prepared pursuant to
the rules and  regulations of  the Securities and  Exchange Commission.  Certain
information   and  note  disclosures  normally   included  in  annual  financial
statements prepared in accordance with generally accepted accounting  principles
have been condensed or omitted pursuant to those rules and regulations, although
the  Company  believes  that  the  disclosures made  are  adequate  to  make the
information presented not misleading. The unaudited interim financial statements
reflect, in  the opinion  of  management, all  adjustments (which  include  only
normal  recurring  adjustments)  necessary  to  fairly  present  the  results of
operations, changes in cash flows and financial  positions as of and at the  end
of   the  periods   presented.  The  unaudited   interim  financial  information
 
                                      F-15
<PAGE>
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                   NOTES TO FINANCIAL STATEMENTS (CONTINUED)
 
12. UNAUDITED INFORMATION (CONTINUED)
should be read in conjunction with the audited financial statements and  related
notes  thereto, appearing elsewhere herein. The  results for the interim periods
presented are not necessarily indicative of results to be expected for the  full
year.
 
    MARCH 1996 AGREEMENTS
 
    On  April  25,  1996 and  June  11, 1996  the  Company borrowed  a  total of
$2,000,000 and  issued 100,000  warrants under  the 1996  Credit Agreement.  The
proceeds  from the two draws  were allocated between the  debt of $1,868,000 and
the estimated fair value of the warrants  of $132,000. The debt will be  written
up  to its face value of $2,000,000 using the effective interest method over the
terms of the debt. The  debt issuance costs will be  amortized over the life  of
the  agreement. At  the time  of the  closing of  the Offering,  the outstanding
balance under the 1996 Credit Agreement will be converted into common stock  and
any remaining debt discount and debt issuance costs will be expensed.
 
    The  $3,000,000 total draws (including the  $1,000,000 initial draw on March
8, 1996, see Note 11) under the 1996 Credit Agreement is mandatorily convertible
into common stock upon closing of the Offering at a conversion price of one-half
of the Offering price. The Company will record a non-cash expense of  $2,100,000
upon closing of the offering to reflect this discount.
 
    COMMON STOCK OPTIONS
 
    In  June 1996,  the 1991 Stock  Option Plan  was amended to  provide for the
granting of options to purchase up  to 1,900,000 shares of the Company's  common
stock.  Stock options activity for the three  months ended March 31, 1996 was as
follows:
 
<TABLE>
<CAPTION>
                                                                                                 EXERCISE
                                                                                                   PRICE
                                                                            NUMBER OF SHARES     PER SHARE
                                                                            -----------------  -------------
<S>                                                                         <C>                <C>
Balance, December 31, 1995................................................            579,071  $ .06 - $4.50
  Granted.................................................................            221,992  $        4.50
  Exercised...............................................................              (534)  $        4.50
  Cancelled...............................................................         --
                                                                            -----------------
Balance, March 31, 1996...................................................            800,529  $ .06 - $4.50
                                                                            -----------------
                                                                            -----------------
</TABLE>
 
    Subsequent to March 31,  1996 the Company  granted 435,651 options,  options
covering  911 shares were  exercised at prices  ranging from $0.60  to $4.50 per
share and 32,661  options were cancelled.  All options granted  in 1996 were  at
$4.50  or  85% of  the Offering  price per  share if  the Company  completes the
Offering within six months from the date of grant.
 
    ATHENA AGREEMENT
 
    On July 1, 1996, the Company entered into an exclusive agreement with Athena
Neurosciences, Inc. ("Athena"),  a wholly-owned subsidiary  of Elan  Corporation
plc  ("Elan") for the  worldwide marketing, sale  and distribution of Carbatrol.
Carbatrol will be marketed in the United States by Athena and its affiliates  or
sublicensees in the rest of the world. Under the agreement, Athena (i) will make
a  $2.0 million payment within ten days of execution of the agreement, (ii) will
fund all future development costs  associated with Carbatrol which are  approved
by  a steering  committee, (iii)  will make  a milestone  payment of  up to $8.0
million, upon  satisfaction of  certain  conditions, of  which $5.0  million  is
creditable against future royalty payments which may be earned on product sales,
and  (iv) will make future royalty payments to the Company based on net sales of
Carbatrol. Athena  has been  granted the  right to  purchase 220,000  shares  of
common stock in the Offering.
 
                                      F-16
<PAGE>
- ---------------------------------------------
                                   ---------------------------------------------
- ---------------------------------------------
                                   ---------------------------------------------
 
    NO  DEALER, SALESPERSON OR ANY OTHER PERSON  HAS BEEN AUTHORIZED TO GIVE ANY
INFORMATION OR TO  MAKE ANY  REPRESENTATIONS NOT CONTAINED  IN THIS  PROSPECTUS,
AND,  IF GIVEN OR MADE,  SUCH INFORMATION OR REPRESENTATIONS  MUST NOT BE RELIED
UPON AS HAVING BEEN AUTHORIZED BY THE  COMPANY OR ANY OF THE UNDERWRITERS.  THIS
PROSPECTUS  DOES NOT CONSTITUTE AN  OFFER OF ANY SECURITIES  OTHER THAN THOSE TO
WHICH IT RELATES OR AN OFFER TO SELL,  OR A SOLICITATION OF AN OFFER TO BUY,  TO
ANY  PERSON IN  ANY JURISDICTION  WHERE SUCH AN  OFFER OR  SOLICITATION WOULD BE
UNLAWFUL. NEITHER THE DELIVERY  OF THIS PROSPECTUS NOR  ANY SALE MADE  HEREUNDER
SHALL,  UNDER  ANY CIRCUMSTANCES,  CREATE ANY  IMPLICATION THAT  THE INFORMATION
CONTAINED HEREIN IS CORRECT AS OF ANY TIME SUBSEQUENT TO THE DATE HEREOF.
 
                             ---------------------
 
                               TABLE OF CONTENTS
 
<TABLE>
<CAPTION>
                                             Page
                                              ---
<S>                                        <C>
Prospectus Summary.......................          3
Risk Factors.............................          6
Use of Proceeds..........................         15
Dividend Policy..........................         15
Capitalization...........................         16
Dilution.................................         17
Selected Financial Data..................         18
Management's Discussion and Analysis.....         20
Business.................................         24
Management...............................         43
Certain Transactions.....................         51
Principal Stockholders...................         55
Description of Capital Stock.............         56
Shares Eligible for Future Sale..........         58
Underwriting.............................         59
Legal Matters............................         60
Experts..................................         60
Additional Information...................         60
Glossary.................................        G-1
Index to Financial Statements............        F-1
</TABLE>
 
                             ---------------------
 
    UNTIL              , 1996 (25  DAYS AFTER THE DATE OF THIS PROSPECTUS),  ALL
DEALERS EFFECTING TRANSACTIONS IN THE COMMON STOCK, WHETHER OR NOT PARTICIPATING
IN  THIS  DISTRIBUTION, MAY  BE REQUIRED  TO  DELIVER A  PROSPECTUS. THIS  IS IN
ADDITION TO THE OBLIGATIONS  OF DEALERS TO DELIVER  A PROSPECTUS WHEN ACTING  AS
UNDERWRITERS AND WITH RESPECT TO THEIR UNSOLD ALLOTMENTS OR SUBSCRIPTIONS.
 
                                2,200,000 SHARES
 
                                     [LOGO]
 
                                PHARMAVENE, INC.
 
                                  COMMON STOCK
 
                              -------------------
 
                                   PROSPECTUS
                                          , 1996
 
                             ---------------------
 
                                LEHMAN BROTHERS
 
                             VOLPE, WELTY & COMPANY
 
- ---------------------------------------------
                                   ---------------------------------------------
- ---------------------------------------------
                                   ---------------------------------------------
<PAGE>
                                    PART II
                     INFORMATION NOT REQUIRED IN PROSPECTUS
 
ITEM 13.  OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION
 
    The  estimated expenses  payable by  the Registrant  in connection  with the
issuance and  distribution  of  the  securities  being  registered  (other  than
underwriting discounts and commissions) are as follows:
 
<TABLE>
<CAPTION>
                                                                                      AMOUNT
                                                                                    ----------
<S>                                                                                 <C>
SEC Registration Fee..............................................................  $   10,469
NASD Filing Fee...................................................................       3,536
Nasdaq Listing Fee................................................................      35,000
Printing and Engraving Expenses...................................................     250,000
Accounting Fees and Expenses......................................................     180,000
Legal Fees and Expenses...........................................................     350,000
Blue Sky Fees and Expenses........................................................      22,000
Transfer Agent's Fees and Expenses................................................       3,500
Miscellaneous Expenses............................................................      45,495
                                                                                    ----------
    Total.........................................................................  $  900,000
                                                                                    ----------
                                                                                    ----------
</TABLE>
 
ITEM 14.  INDEMNIFICATION OF DIRECTORS AND OFFICERS
 
    The Certificate of Incorporation and By-Laws of the Registrant provides that
the  Company shall  indemnify any  person to  the full  extent permitted  by the
Delaware General Corporation Law (the "GCL").  Section 145 of the GCL,  relating
to indemnification, is hereby incorporated herein by reference.
 
    Insofar  as indemnification for liabilities under  the Securities Act may be
permitted to Directors, officers or controlling persons of the Company  pursuant
to  the Company's By-laws and the  Delaware General Corporation Law, the Company
has been informed that in the opinion of the Securities and Exchange  Commission
such indemnification is against public policy as expressed in the Securities Act
and is therefore unenforceable.
 
    The   Company's  Restated  Certificate  of  Incorporation  includes  certain
provisions permitted pursuant to Delaware law whereby officers and Directors  of
the  Company are  to be indemnified  against certain  liabilities. The Company's
Restated Certificate  of  Incorporation  also  limits,  to  the  fullest  extent
permitted  by  Delaware law,  a director's  liability  for monetary  damages for
breach of fiduciary duty, including  gross negligence, except liability for  (i)
breach  of the director's  duty of loyalty,  (ii) acts or  omissions not in good
faith or which involve intentional misconduct or a knowing violation of the law,
(iii) the  unlawful  payment  of  a  dividend  or  unlawful  stock  purchase  or
redemption  and (iv) any transaction from which the director derives an improper
personal benefit. Delaware law does not eliminate a director's duty of care  and
this  provision has no effect on the  availability of equitable remedies such as
injunction or rescission based upon a director's breach of the duty of care.  In
addition,  the Company has  obtained an insurance  policy providing coverage for
certain liabilities of its officers and Directors.
 
    In accordance with Section 102(a)(7)  of the GCL, the Company's  Certificate
of  Incorporation eliminates the personal liability  of directors to the Company
or its  stockholders for  monetary damages  for breach  of fiduciary  duty as  a
director with certain limited exceptions set forth in Section 102(a)(7).
 
    Reference  is made to Section 10 of the Underwriting Agreement (Exhibit 1.1)
which provides  for indemnification  by  the Underwriters  of the  Company,  its
officers and directors.
 
ITEM 15.  RECENT SALES OF UNREGISTERED SECURITIES
 
    During  the past three years, the Company has issued securities to a limited
number of persons, as described below. No underwriter or underwriting  discounts
or  commissions  were  involved.  There  was  no  public  offering  in  any such
transaction and the Company believes that  each transaction was exempt from  the
registration  requirements of the Securities Act  of 1933 (the "Securities Act")
by reason of Sections 3(b) and
 
                                      II-1
<PAGE>
4(2)  thereof  based  on  the  private  nature  of  the  transactions  and   the
sophistication of the purchasers, all of whom had access to complete information
concerning the Company and acquired the securities for investment and not with a
view to the distribution thereof.
 
    Since its inception to July 1, 1996, the Company has issued 72,241 shares of
Common  Stock pursuant to exercise of  employee stock options at exercise prices
per share  ranging from  $.06 to  $5.70,  and has  granted options  to  purchase
1,357,560  shares of its Common Stock to employees, directors and consultants at
exercise prices ranging from $.06 to $10.80.
 
    In June,  September and  November 1993,  the Company  sold an  aggregate  of
5,025,000,  1,325,001 and  1,325,000 shares  of Series  A Preferred  Stock for a
purchase price of $1.00 per share to a group of investors including HCV III, HCV
IV, The State of Michigan, Aetna and Everest Trust. These shares are convertible
into an aggregate of  1,705,556 shares of Common  Stock upon completion of  this
offering. In February 1994, the Company sold an aggregate of 1,324,999 shares of
Series  A Preferred Stock for a purchase price  of $1.00 per share to a group of
investors. These shares are convertible into  an aggregate of 294,445 shares  of
Common Stock upon completion of this offering.
 
    In  April 1993, the  Company sold to  HCV II for  a price of  $.01 per share
Preferred Stock Warrants to purchase 41,667  shares of Series A Preferred  Stock
at  an exercise  price of  $1.00 per  share and  1,686 Common  Stock Warrants to
certain shareholders, of which 802 remain outstanding and 884 were exercised.
 
    In August and December 1992,  the Company sold to  HCV II and others  Common
Stock  Warrants to purchase an aggregate of 111,111 shares of Common Stock for a
price of $.06 per share. These warrants  are exercisable at a price of $.06  per
share.  In December 1992, the Company sold 139,518 shares of Common Stock to HCV
II, 22,422 shares of Common  Stock to Everest Trust  and 4,729 shares of  Common
Stock to other investors.
 
    In  May  1994,  the  Company  issued  an  aggregate  of  $2,000,000  7  1/4%
Convertible Promissory Notes (the "1994 Notes")  and warrants to purchase up  to
an aggregate of 33,337 shares of Common Stock at an exercise price of $10.80 per
share  to  a group  of  stockholders including  HCV III,  HCV  IV, The  State of
Michigan, Aetna and Everest Trust (the "1994 Lenders"). In May 1995, the Company
issued 1,599,997 shares of Series A Preferred Stock to the 1994 Lenders pursuant
to an  agreement to  convert the  1994 Notes  (the "Conversion  Agreement").  In
February  1996, the Company issued 1,066,663  shares of Series A Preferred Stock
to the 1994 Lenders under the terms of the Conversion Agreement.
 
    The Company  issued  an  aggregate  of $8,000,000  principal  amount  of  9%
promissory  notes  (the  "1995  Notes") to  certain  stockholders  and officers,
including HCV III, HCV IV, The State of Michigan, Everest Trust, James D. Russo,
James D. Isbister and George W.  Belendiuk (the "1995 Lenders"). In March  1996,
the  1995 Notes were converted into an aggregate of 8,000,000 shares of Series A
Preferred Stock. The Company also  issued warrants to purchase 1,200,000  shares
of  Series A Preferred Stock at an exercise  price of $.96 per share pursuant to
the 1995 Credit  Agreement to  the 1995 Lenders.  In October  1995, the  Company
agreed  to issue ten-year warrants to purchase  50,000 shares of Common Stock at
an exercise price equal to  the public offering price per  share to HCV III  and
HCV IV.
 
    In March 1996, the Company entered into two credit agreements (collectively,
the  "1996 Credit Agreement") with certain  stockholders, including HCV III, HCV
IV and Everest Trust (the "1996 Lenders") and issued an aggregate of  $3,000,000
principal  amount of  8 1/2%  promissory notes  (the "1996  Notes") to  the 1996
Lenders. In connection  with the  execution of  the 1996  Credit Agreement,  the
Company  issued an aggregate  of 730,000 ten-year warrants  to purchase Series A
Preferred Stock to the 1996 Lenders at  an exercise price of $.75 per share.  In
connection  with the issuance of the 1996 Notes, the Company issued an aggregate
of 150,000 ten-year warrants to purchase Series A Preferred Stock at an exercise
price of $.75 per share. The 1996 Notes are convertible into shares of Series  A
Preferred  Stock  at a  conversion price  equal to  one-half the  initial public
offering price per share.
 
    The above  transactions were  private transactions  not involving  a  public
offering  and were exempt from the registration provisions of the Securities Act
pursuant   to   Section   4(2)   thereof.    The   sale   of   securities    was
 
                                      II-2
<PAGE>
without  the use of  an underwriter, and the  certificates evidencing the shares
bear a restrictive legend permitting the transfer thereof only upon registration
of the shares or an exemption under the Securities Act.
 
ITEM 16.  EXHIBITS
 
<TABLE>
<C>           <S>
      1.1.    Form of Underwriting Agreement*
      3.2     Fourth Restated Certificate of Incorporation*
      3.2(a)  Amendment to Fourth Restated Certificate of Incorporation*
      3.2(b)  Second Amendment to Fourth Restated Certificate of Incorporation*
      3.2(c)  Third Amendment to Fourth Restated Certificate of Incorporation*
      3.3.    By-laws, as amended*
      4.1.    Form of Common Stock Certificate*
      5.1.    Opinion of  Bachner, Tally,  Polevoy &  Misher LLP  regarding legality  of
               securities offered
     10.1     Employment  Agreement  dated April  15,  1993 between  the  Registrant and
               Edward M. Rudnic, Ph.D.*
     10.1(a)  Employment Agreement dated July 1, 1996 between the Registrant and  Edward
               M. Rudnic, Ph.D.
     10.2     Employment  Agreement dated July 1, 1996  between the Registrant and James
               D. Russo
     10.3     Employment Agreement dated as  of January 1,  1993 between the  Registrant
               and George W. Belendiuk, M.D., Ph.D.*
     10.4     Employment  Agreement dated as of July  1, 1996 between the Registrant and
               Krystyna Belendiuk, Ph.D.
     10.5     Restricted Stock  Purchase  Agreement  dated July  11,  1991  between  the
               Registrant and George W. Belendiuk*
     10.6     Employment Agreement between the Registrant and James D. Isbister*
     10.6(a)  Restricted  Stock  Purchase  Agreement  dated July  29,  1991  between the
               Registrant and James D. Isbister*
     10.6(b)  Continuing Services  Agreement  dated  as  of July  1,  1996  between  the
               Registrant and James D. Isbister
     10.7     1991 Stock Option Plan, as amended*
     10.8     Form of Stock Option Agreement*
     10.9     Sublease Agreement dated March 29, 1995 between the Registrant and Corning
               Clinical Laboratories, Inc.*
     10.10    Sublease Agreement Amendment dated June 2, 1995 between the Registrant and
               Corning Clinical Laboratories, Inc.*
     10.11    Convertible Preferred Stock Purchase Agreement dated June 1, 1993*
     10.12    Third Amended and Restated Stockholders' Agreement dated June 1, 1993, and
               amendments.*
     10.12(a) Fourth   Amendment  to  the  Third   Amended  and  Restated  Stockholders'
               Agreement*
     10.13    Credit Agreement  dated as  of  May 3,  1994  between the  Registrant  and
               certain  stockholders, with  form of  Warrant and  Convertible Promissory
               Note attached.*
     10.14    Form of  Warrant to  purchase shares  of Common  Stock dated  May 3,  1994
               issued to Everest Trust pursuant to Exhibit 10.13.*
</TABLE>
 
                                      II-3
<PAGE>
<TABLE>
<C>           <S>
     10.15    Conversion and Subscription Agreement dated as of May 22, 1995 between the
               Registrant and the signatories of the May 3, 1994 Credit Agreement.*
     10.15(a) Form of Amendment No. 1 to Conversion and Subscription Agreement*
     10.15(b) Form of Amendment No. 2 to Conversion and Subscription Agreement.
     10.16    Credit  Agreement dated as of May  22, 1995 between Registrant and certain
               stockholders, with  form  of  Convertible Promissory  Note  and  Form  of
               Warrant  to  purchase  shares  of Series  A  Convertible  Preferred Stock
               attached.*
     10.16(a) Form of Amendment No. 1 to Credit Agreement*
     10.17+   License Agreement between  the Registrant and  Rhone-Poulenc Rorer,  Inc.,
               dated as of August 25, 1994.*
     10.18+   Manufacturing  Agreement  dated  as  of  September  30,  1993  between the
               Registrant and Niro Inc.*
     10.19    Form of Consent and Agreement to Amend between the Registrant and  certain
               stockholders dated as of November 30, 1995.
     10.20    Form of warrant to purchase Common Stock issued to HCV III and HCV IV*
     10.21    Credit  Agreement for  up to  $4,300,000 dated  March 7,  1996 between the
               Registrant and certain stockholders, with form of Convertible  Promissory
               Note attached*
     10.22    Credit  Agreement for  up to  $3,000,000 dated  March 7,  1996 between the
               Registrant and certain stockholders, with form of Convertible  Promissory
               Note attached*
     10.23    Form of warrant to purchase shares of Series A Convertible Preferred Stock
               dated March 11, 1996 issued to HCV III pursuant to Exhibit 10.21*
     10.24    Conversion  and  Subscription Agreement  dated March  7, 1996  between the
               Registrant and Certain Stockholders*
     10.25+   Agreement dated as  of May 28,  1996 between the  Registrant and The  P.F.
               Laboratories, Inc.
     10.26+   License  Agreement dated  as of  July 1,  1996 between  the Registrant and
               Athena Neurosciences, Inc.
     10.27    Employment Agreement dated as of June 25, 1996 between the Registrant  and
               Robert S. Cohen
     11.1     Computation of Historical Loss Per Share
     24.1     Consent  of Bachner, Tally, Polevoy &  Misher LLP (included in its opinion
               filed as Exhibit 5.1 hereto)
     24.2     Consent of Coopers & Lybrand L.L.P. -- Included on Page II-7
     24.3     Consent of Carella, Byrne, Baine, Gilfillan, Cecchi, Stewart & Olstein*
     24.4     Consent of Olsson, Frank and Weeda, P.C. -- included on Page II-8
     25.1     Power of Attorney*
</TABLE>
 
- --------------
* Previously filed
 
+ Confidential treatment has been requested.
 
    (b)Financial Statement Schedules
 
                                      II-4
<PAGE>
ITEM 17.  UNDERTAKINGS
 
    Undertakings Required by Regulation S-K, Item 512(g).
 
    The undersigned registrant hereby undertakes  to provide to the  Underwriter
at  the closing  specified in  the Underwriting  Agreement certificates  in such
denominations and registered  in such names  as required by  the Underwriter  to
permit prompt delivery to each purchaser.
 
    Undertaking Required by Regulation S-K, Item 512(h).
 
    Insofar  as indemnification for liabilities arising under the Securities Act
of 1933 may be  permitted to directors, officers  or controlling persons of  the
registrant  pursuant to the  foregoing provisions, or  otherwise, the registrant
has been advised that in the  opinion of the Securities and Exchange  Commission
such  indemnification is against public  policy as expressed in  the Act and is,
therefore, unenforceable. In the event that a claim for indemnification  against
such  liabilities (other than the payment by the registrant of expenses incurred
or paid by a director,  officer or controlling person  of the registrant in  the
successful  defense  of any  action,  suit or  proceeding)  is asserted  by such
director, officer or controlling person in connection with the securities  being
registered, the registrant will, unless in the opinion of its counsel the matter
has  been settled  by controlling  precedent, submit  to a  court of appropriate
jurisdiction the question whether such  indemnification by it is against  public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.
 
    Undertakings required by Regulation S-K, Item 512(i).
 
    The undersigned registrant hereby undertakes that:
 
    (1)For  purposes of  determining any liability  under the  Securities Act of
       1933, as amended,  the information  omitted from the  form of  prospectus
filed  as part  of this  Registration Statement in  reliance upon  Rule 430A and
contained in the  form of prospectus  filed by the  Registrant pursuant to  Rule
424(b)(1)  or (4) or 497(h) under the Securities  Act shall be deemed to be part
of this Registration Statement as of the time it was declared effective.
 
    (2)For purposes of  determining any  liability under the  Securities Act  of
       1933,  each post-effective amendment  that contains a  form of prospectus
shall be deemed to  be a new registration  statement relating to the  securities
offered  therein, and  the offering  of such  securities at  that time  shall be
deemed to be the initial bona fide offering thereof.
 
                                      II-5
<PAGE>
                               CONSENT OF COUNSEL
 
    The consent of  Bachner, Tally,  Polevoy & Misher  LLP is  contained in  its
opinion filed as Exhibit 5.1 to the Registration Statement.
 
                                      II-6
<PAGE>
                                                                    EXHIBIT 24.2
 
                       CONSENT OF INDEPENDENT ACCOUNTANTS
 
We  consent to inclusion  in this Registration  Statement on Form  S-1 (File No.
33-98706) of our  report dated January  24, 1996 (except  as to the  information
presented  in Note 11, for which  the date is March 14,  1996), on our audits of
the financial statements as of December 31, 1993, 1994 and 1995, and for each of
the three  years in  the period  ended December  31, 1995,  and for  the  period
February  16, 1990 (date of inception) to  December 31, 1995 of Pharmavene, Inc.
We also consent to the references to  our firm under the captions "Experts"  and
"Selected Financial Data" in the Prospectus.
 
                                          COOPERS & LYBRAND L.L.P.
 
Rockville, Maryland
July 3, 1996
 
                                      II-7
<PAGE>
                                                                   EXHIBIT 24.4.
 
                               CONSENT OF COUNSEL
 
The  undersigned hereby consents to the use  of our name, and the statement with
respect to  us appearing  under  the heading  "Legal  Matters" included  in  the
Registration  Statement. We further consent to the incorporation by reference of
this consent  pursuant to  Rule 439(b)  under  the Securities  Act of  1933,  as
amended  (the "Securities Act"), into  any subsequent registration statement for
the same offering that may be filed pursuant to Rule 462(b) under the Securities
Act.
 
                                          OLSSON, FRANK AND WEEDA, P.C.
 
Washington, D.C.
June 28, 1996
 
                                      II-8
<PAGE>
                                   SIGNATURES
 
    Pursuant  to the requirements of the  Securities Act of 1933, the registrant
has duly caused this Registration  Statement to be signed  on its behalf by  the
undersigned,  thereunto  duly authorized,  in the  City  of Rockville,  State of
Maryland on the 3rd day of July, 1996.
 
                                          PHARMAVENE, INC.
 
                                          By: _______/s/_JAMES D. ISBISTER______
                                                      James D. Isbister
                                                 CHIEF EXECUTIVE OFFICER AND
                                                           DIRECTOR
 
                                   SIGNATURE
 
    Pursuant  to  the  requirements  of   the  Securities  Act  of  1933,   this
Registration  Statement  has  been  signed  by  the  following  persons  in  the
capacities and on the dates indicated.
 
<TABLE>
<CAPTION>
                       SIGNATURE                                           TITLE                        DATE
- -------------------------------------------------------  -----------------------------------------  -------------
 
<C>                                                      <S>                                        <C>
                 /s/JAMES D. ISBISTER                    Chief Executive Officer and Director       July 3, 1996
                   James D. Isbister                      (principal executive officer)
 
             /s/KRYSTYNA BELENDIUK, PH.D.                Senior Vice President -- Business          July 3, 1996
               Krystyna Belendiuk, Ph.D.                  Development and Director
 
                                                         Senior Vice President and Chief Financial
                   /s/JAMES D. RUSSO                      Officer (principal financial and          July 3, 1996
                    James D. Russo                        accounting officer)
 
             /s/JAMES H. CAVANAUGH, PH.D.                Director                                   July 3, 1996
               James H. Cavanaugh, Ph.D.
 
                  /s/MAX LINK, PH.D.                     Director                                   July 3, 1996
                    Max Link, Ph.D.
 
                  /s/LAWRENCE C. HOFF                    Director                                   July 3, 1996
                   Lawrence C. Hoff
 
                 /s/JAMES D. ISBISTER
                  *James D. Isbister
                 (AS ATTORNEY-IN-FACT)
</TABLE>
 
                                      II-9
<PAGE>
                                 EXHIBIT INDEX
 
<TABLE>
<CAPTION>
  EXHIBITS
    NO.                                                                                              PAGE
- ------------                                                                                       ---------
<C>           <S>                                                                                  <C>
    1.1.      Form of Underwriting Agreement*
    3.2       Fourth Restated Certificate of Incorporation*
    3.2  (a)  Amendment to Fourth Restated Certificate of Incorporation*
    3.2  (b)  Second Amendment to Fourth Restated Certificate of Incorporation*
    3.2  (c)  Third Amendment to Fourth Restated Certificate of Incorporation*
    3.3.      By-laws, as amended*
    4.1.      Form of Common Stock Certificate*
    5.1.      Opinion  of Bachner, Tally,  Polevoy & Misher LLP  regarding legality of securities
               offered
   10.1       Employment Agreement dated  April 15,  1993 between  the Registrant  and Edward  M.
               Rudnic, Ph.D.*
   10.1  (a)  Employment  Agreement  dated July  1,  1996 between  the  Registrant and  Edward M.
               Rudnic, Ph.D.
   10.2       Employment Agreement dated July 1, 1996 between the Registrant and James D. Russo
   10.3       Employment Agreement dated as of January 1, 1993 between the Registrant and  George
               W. Belendiuk, M.D., Ph.D.*
   10.4       Employment  Agreement dated as of July 1,  1996 between the Registrant and Krystyna
               Belendiuk, Ph.D.
   10.5       Restricted Stock Purchase Agreement dated July 11, 1991 between the Registrant  and
               George W. Belendiuk*
   10.6       Employment Agreement between the Registrant and James D. Isbister*
   10.6  (a)  Restricted  Stock Purchase Agreement dated July 29, 1991 between the Registrant and
               James D. Isbister*
   10.6  (b)  Continuing Services Agreement dated as of  July 1, 1996 between the Registrant  and
               James D. Isbister
   10.7       1991 Stock Option Plan, as amended*
   10.8       Form of Stock Option Agreement*
   10.9       Sublease Agreement dated March 29, 1995 between the Registrant and Corning Clinical
               Laboratories, Inc.*
   10.10      Sublease  Agreement Amendment dated June 2, 1995 between the Registrant and Corning
               Clinical Laboratories, Inc.*
   10.11      Convertible Preferred Stock Purchase Agreement dated June 1, 1993*
   10.12      Third Amended  and  Restated  Stockholders'  Agreement  dated  June  1,  1993,  and
               amendments.*
   10.12 (a)  Fourth Amendment to the Third Amended and Restated Stockholders' Agreement*
   10.13      Credit  Agreement  dated as  of  May 3,  1994  between the  Registrant  and certain
               stockholders, with form of Warrant and Convertible Promissory Note attached.*
   10.14      Form of Warrant  to purchase shares  of Common Stock  dated May 3,  1994 issued  to
               Everest Trust pursuant to Exhibit 10.13.*
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
  EXHIBITS
    NO.                                                                                              PAGE
- ------------                                                                                       ---------
   10.15      Conversion  and  Subscription  Agreement  dated  as of  May  22,  1995  between the
               Registrant and the signatories of the May 3, 1994 Credit Agreement.*
<C>           <S>                                                                                  <C>
   10.15 (a)  Form of Amendment No. 1 to Conversion and Subscription Agreement*
   10.15 (b)  Form of Amendment No. 2 to Conversion and Subscription Agreement.
   10.16      Credit  Agreement  dated  as  of  May  22,  1995  between  Registrant  and  certain
               stockholders,  with form  of Convertible  Promissory Note  and Form  of Warrant to
               purchase shares of Series A Convertible Preferred Stock attached.*
   10.16 (a)  Form of Amendment No. 1 to Credit Agreement*
   10.17 +    License Agreement between the Registrant and Rhone-Poulenc Rorer, Inc., dated as of
               August 25, 1994.*
   10.18 +    Manufacturing Agreement dated as of September  30, 1993 between the Registrant  and
               Niro Inc.*
   10.19      Form  of  Consent  and  Agreement  to  Amend  between  the  Registrant  and certain
               stockholders dated as of November 30, 1995.
   10.20      Form of warrant to purchase Common Stock issued to HCV III and HCV IV*
   10.21      Credit Agreement for up  to $4,300,000 dated March  7, 1996 between the  Registrant
               and certain stockholders, with form of Convertible Promissory Note attached*
   10.22      Credit  Agreement for up to  $3,000,000 dated March 7,  1996 between the Registrant
               and certain stockholders, with form of Convertible Promissory Note attached*
   10.23      Form of warrant to  purchase shares of Series  A Convertible Preferred Stock  dated
               March 11, 1996 issued to HCV III pursuant to Exhibit 10.21*
   10.24      Conversion  and Subscription Agreement  dated March 7,  1996 between the Registrant
               and Certain Stockholders*
   10.25 +    Agreement  dated  as  of  May  28,  1996  between  the  Registrant  and  The   P.F.
               Laboratories, Inc.
   10.26 +    License  Agreement  dated as  of July  1,  1996 between  the Registrant  and Athena
               Neurosciences, Inc.
   10.27      Employment Agreement dated as of June 25, 1996 between the Registrant and Robert S.
               Cohen
   11.1       Computation of Historical Loss Per Share
   24.1       Consent of Bachner, Tally, Polevoy & Misher  LLP (included in its opinion filed  as
               Exhibit 5.1 hereto)
   24.2       Consent of Coopers & Lybrand L.L.P. -- Included on Page II-7
   24.3       Consent of Carella, Byrne, Baine, Gilfillan, Cecchi, Stewart & Olstein*
   24.4       Consent of Olsson, Frank and Weeda, P.C. -- included on Page II-8
   25.1       Power of Attorney*
</TABLE>
 
- --------------
* Previously filed
 
+ Confidential treatment has been requested.
 
    (b)Financial Statement Schedules

<PAGE>

                              July 3, 1996




Pharmavene, Inc.
1550 East Gude Drive
Rockville, MD  20850

Ladies & Gentlemen:

     We have acted as counsel to Pharmavene, Inc. (the "Company") in connection
with its filing of a registration statement on Form S-1 (File No. 33-98706) (the
"Registration Statement"), under the Securities Act of 1933, as amended (the
"Act") covering 2,530,000 shares (the "Shares") of Common Stock, $.01 par value
(the "Common Stock"), including 330,000 Shares subject to an over-allotment
option, all as more particularly described in the Registration Statement.

     In our capacity as counsel to the Company, we have examined the Company's
Certificate of Incorporation, as amended and By-laws and the minutes and other
corporate proceedings of the Company.  With respect to factual matters, we have
relied upon statements and certificates of officers of the Company.  We have
also reviewed such other matters of law and examined and relied upon such other
documents, records and certificates as we have deemed relevant hereto.  In all
such examinations we have assumed conformity with the original documents of all
documents submitted to us as originals and the genuineness of all signatures on
all documents submitted to us.

     On the basis of the foregoing, it is our opinion that the Shares covered by
and included in the Registration Statement have been duly and validly authorized
and will, when sold, paid for and issued as contemplated by the Registration
Statement, be legally issued, fully paid and non-assessable.

<PAGE>

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference made to us under the caption "Legal
Matters" in the prospectus constituting part of the Registration Statement.  In
giving this consent, we do not thereby concede that we come within the
categories of persons whose consent is required by the Act or the General Rules
and Regulations promulgated thereunder.

                              Very truly yours,




                              BACHNER, TALLY, POLEVOY & MISHER LLP

BTPM/TB/npm

<PAGE>

                              EMPLOYMENT AGREEMENT


         This EMPLOYMENT AGREEMENT, dated as of July 1, 1996 is entered into by
and between PHARMAVENE, INC., a Delaware corporation (the "Company") and Edward
M. Rudnic, Ph.D. (the "Employee").

         WHEREAS, the Company desires to employ the Employee as Senior Vice
President, Development and Technical Operations of the Company, and the Employee
desires to accept such employment by the Company, on the terms and subject to
the conditions hereinafter set forth.

         NOW, THEREFORE, in consideration of the mutual covenants and
obligations hereinafter set forth, the parties hereto agree as follows:

         1.   EMPLOYMENT.  The Company hereby employs the Employee, and the
Employee hereby accepts employment by the Company, upon the terms and conditions
hereinafter set forth.

         2.   TERM.  Subject to the provisions of SECTIONS 6, 7, 8, and 9 below,
the employment of the Employee hereunder will be for the two-year period
commencing on the date hereof (the "Commencement Date") and ending on the second
anniversary of such Commencement Date.  Unless either party gives written notice
of determination not to renew at least one hundred eighty (180) days prior to
the second anniversary of the Commencement Date, this Agreement shall be renewed
for one (1) year from that anniversary.  Thereafter, unless either party gives
written notice of determination not to renew at least one hundred eighty (180)
days prior to any succeeding anniversary of the Commencement Date, this
Agreement shall be renewed for one (1) year from each anniversary.  The term
"Employment Period" shall mean the two-year period provided for in this
SECTION 2 and any extension thereof, or any shorter period resulting from any
termination of employment under SECTION 6, 7, 8, or 9 below.

         3.   DUTIES AND RESPONSIBILITIES.  The Employee will be employed as
Senior Vice President, Development and Technical Operations of the Company.  The
Employee will perform such duties and services, consistent with his position, as
may be assigned to him from time to time by the Board of Directors or the
President of the Company or the Board's or President's designee.  In furtherance
of the foregoing, the Employee hereby agrees to perform well and faithfully such
duties and responsibilities and the other reasonable duties and responsibilities
assigned to him from time to time by the Board of Directors of the Company or
the President or the Board's or President's designee.

         4.   TIME TO BE DEVOTED TO EMPLOYMENT.  Except for reasonable
vacations, absences due to temporary illness, and activities which have been
mutually agreed to by the parties,  the Employee shall devote substantially all
of his time, attention and energies to the business of the Company during the
Employment Period.  During the Employment Period, the Employee will not be
engaged in any other business activity which, in the reasonable judgment of the
Company, conflicts with the duties of the Employee hereunder, whether or not
such activity is pursued for gain, profit or other pecuniary advantage.

         5.   COMPENSATION; REIMBURSEMENT.  (a)  The Company (or, at the
Company's option, any subsidiary or affiliate thereof) will pay to the Employee
(i) an annual base salary (the "Base Salary") of not less than $153,000.00,
payable in such installments as is the policy of the Company with respect to
employees of the Company at substantially the same employment level as the
Employee.

<PAGE>

         (b)  During the Employment Period, the Employee will be entitled to the
fringe benefits that are made available from time to time to employees of the
Company at substantially the same employment level as the Employee, including
eligibility to participate in any Company stock option or bonus plans.

         (c)  The Company will reimburse the Employee, in accordance with the
practice of the Company from time to time, for all reasonable and necessary
travel expenses and other disbursements incurred by him for or on behalf of the
Company in the performance of his duties hereunder upon presentation by the
Employee to the Company of appropriate vouchers.

         6.   INVOLUNTARY TERMINATION.  If the Employee dies, then the
Employee's employment shall be deemed to terminate on the date of the Employee's
death.  If the Employee is incapacitated or disabled by accident, sickness or
otherwise so as to render him mentally or physically incapable of performing the
services required to be performed by him under this Agreement for a period of
ninety (90) consecutive days or longer, or for ninety (90) days during any six-
month period (such condition being herein referred to as "Disability"), then the
Company, at its option, may terminate the employment of the Employee under this
Agreement immediately upon giving him notice to that effect.  In the case of a
Disability, until the Company shall have terminated the Employee's employment
hereunder in accordance with the foregoing, the Employee will be entitled to
receive compensation, at the rate and in the manner provided in SECTION 5 above,
notwithstanding any such Disability.  Termination pursuant to this SECTION 6 is
hereinafter referred to as an "Involuntary Termination".

         7.   TERMINATION FOR CAUSE.  Upon a vote of the majority of the Board
of Directors or in the discretion of the President of the Company, the Company
may terminate the employment of the Employee hereunder at any time during the
Employment Period for "cause" (such termination being hereinafter referred to as
a "Termination for Cause") by giving the Employee notice of such termination,
whereupon such termination shall take effect immediately.  For the purpose of
this SECTION 7, "cause" will mean (a) the Employee's willful misconduct with
respect to the business and affairs of the Company or any subsidiary or
affiliate thereof, (b) the Employee's neglect of duties or failure to act which
can reasonably be expected to affect materially and adversely the business or
affairs of the Company or any subsidiary or affiliate thereof, (c) the
Employee's material breach of any of the agreements contained in SECTION 3 or 4
hereof, or the Employee's breach of the Proprietary Information and Invention
Agreement referred to in SECTION 11 below, (d) the commission by the Employee of
an act involving moral turpitude relating to the Company or fraud, or (e) the
Employee's conviction of any felony, or of any misdemeanor involving fraud,
theft, embezzlement, forgery or moral turpitude.

         8.   TERMINATION WITHOUT CAUSE.  The Company may terminate the
employment of the Employee hereunder at any time during the Employment Period
without "cause" (such termination being hereinafter referred to as a
"Termination Without Cause") by giving the Employee written notice of such
termination.  Upon the giving of such notice, termination of employment under
this SECTION 8 will take effect immediately.

         9.   VOLUNTARY TERMINATION.  Any termination of the employment of the
Employee hereunder otherwise than as a result of an Involuntary Termination, a
Termination For Cause or a Termination Without Cause will be referred
hereinafter as a "Voluntary Termination."  Following reasonable notice, a
Voluntary Termination will be deemed to be


                                       -2-
<PAGE>

effective upon the date specified in such notice or, in the absence of such
specification, upon the date of the giving of such notice.

         10.  EFFECT OF TERMINATION OF EMPLOYMENT.  (a)  Upon termination of the
Employee's employment hereunder pursuant to a Voluntary Termination or a
Termination For Cause, neither the Employee nor his beneficiary or estate will
have any further rights or claims against the Company under this Agreement
except to receive:

          (i)    the unpaid portion of the Base Salary provided for in
SECTION 5(a) above, computed on a PRO RATA basis to the date of such
termination; and

          (ii)   reimbursement for any expenses for which the Employee shall not
have theretofore been reimbursed as provided in SECTION 5(c) above.

          (iii)  retention in the Company's 401(k) Program and other Company
employee benefits (as required by law) and the opportunity to purchase health
benefits under the Company's health benefits program, as required by COBRA.

         (b)  Upon termination of the Employee's employment hereunder pursuant
to an Involuntary Termination, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to six (6) months' Base
Salary, payable at the same rate and in the same manner as set forth in
SECTION 5 above.

         (c)  Upon termination of the Employee's employment hereunder pursuant
to a Termination Without Cause, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to the lesser of (i) one (1)
year's Base Salary, payable in twelve (12) equal monthly installments or (ii)
nine (9) months' Base Salary or the Base Salary for the then remaining term of
the Employment Period, whichever is greater, in each case payable at the same
rate and in the same manner as set forth in SECTION 5 above.

         11.  PROPRIETARY INFORMATION AND INVENTION AGREEMENT.  The Employee has
executed the Proprietary Information and Invention Agreement, a copy of which is
attached hereto as EXHIBIT A, and covenants that he will comply with the terms
of such Proprietary Information and Invention Agreement during the term thereof.

         12.  ENFORCEMENT.  It is the desire and intent of the parties hereto
that the provisions of this Agreement will be enforced to the fullest extent
permissible under the laws and public policies applied in each jurisdiction in
which enforcement is sought.  Accordingly, to the extent that a restriction
contained in this Agreement is more restrictive than permitted by the laws of
any jurisdiction where this Agreement may be subject to review and
interpretation, the terms of such restriction, for the purpose only of the
operation of such restriction in such jurisdiction, will be the maximum
restriction allowed by the laws of such jurisdiction and such restriction will
be deemed to have been revised accordingly herein.  A court having jurisdiction
over an action arising out of or seeking enforcement of any restriction
contained in this Agreement may modify the terms of such restriction in
accordance with this SECTION 12.

         13.  REMEDIES; SURVIVAL.  (a)  The Employee acknowledges and
understands that the provisions of this Agreement are of a special and unique
nature, the loss of which


                                       -3-
<PAGE>


cannot be accurately compensated for in damages by an action at law, and that
the breach or threatened breach of the provisions of this Agreement would cause
the Company irreparable harm.  In the event of a breach or threatened breach by
the Employee of the provisions of SECTION 11 above, the Company will be entitled
to an injunction restraining him from such breach.  Nothing herein contained
will be construed as prohibiting the Company from pursuing any other remedies
available at law for any breach or threatened breach of this Agreement.

         (b)  Notwithstanding anything contained in this Agreement to the
contrary, the provisions of SECTIONS 11, 12, 14, 15, 16, 20, 21 and this
SECTION 13, will survive the expiration or other termination of this Agreement
until, by their terms, such provisions are no longer operative.


         14.  STOCK OPTIONS.  In the event the Employee is terminated from the
Company or a subsidiary within one (1) year of either of the events specified in
(i) or (ii) below, or the employee's responsibilities or duties are
substantially reduced within one (1) year of either of the events specified in
(i) or (ii) below, all outstanding Stock Options at that date of termination or
date of reduction of responsibilities or duties shall become immediately
exercisable for a period of three (3) months.

          (i)   as a result of or in connection with any tender offer,
                exchange offer, merger or other business combination, sale of
                assets or contested election, or combination of the
                foregoing, the persons who were Directors of the Corporation
                just prior to such event cease to constitute a majority of
                the Corporation's Board of Directors; or

          (ii)  the stockholders of the Corporation approve an agreement
                providing for a transaction in which the Corporation will
                cease to be an independent publicly-owned corporation or a
                sale or other disposition of all or substantially all of the
                assets of the Corporation occurs.

         15.  NOTICES.  All notices, demands and other communications which are
required to be given, served or sent pursuant to this Agreement will be in
writing and will be delivered personally or sent by air courier or first class
certified or registered mail, return receipt requested and postage prepaid,
addressed as follows:

         If to the Employee:

         Edward M. Rudnic, Ph.D.
          15103 Gravenstein Way
         North Potomac, Maryland  20878

         If to the Company:

         Pharmavene, Inc.
         1550 East Gude Drive
         Rockville, Maryland  20850

         Attention:  President


All notices and other communications given to any party hereto in accordance
with the provisions of this Agreement will be deemed to have been given on the
date of delivery if


                                       -4-
<PAGE>

personally delivered; on the business day after the date when sent if sent by
air courier; and on the third business day after the date when sent if sent by
mail, in each case addressed to such party as provided in this SECTION 14 or in
accordance with the latest unrevoked direction from such party.

         16.  BINDING AGREEMENT; BENEFIT.  The provisions of this Agreement will
be binding upon and will inure to the benefit of, the respective heirs, legal
representatives and successors of the parties hereto.

         17.  GOVERNING LAW.  This Agreement will be governed by, and construed
and enforced in accordance with, the laws of the State of Maryland (not
including the choice of law provisions thereof).

         18.  WAIVER OF BREACH.  The waiver by either party of a breach of any
provision of this Agreement by the other party must be in writing and will not
operate or be construed as a waiver of any subsequent breach by such other
party.

         19.  ENTIRE AGREEMENT; AMENDMENTS.  This Agreement contains the entire
agreement between the parties with respect to the subject matter hereof and
supersedes all prior agreements or understanding among the parties with respect
thereto.  This Agreement may be amended only by an agreement in writing signed
by the parties hereto.

         20.  HEADINGS.  The Section headings contained in this Agreement are
for reference purposes only and will not affect in any way the meaning or
interpretation of this Agreement.

         21.  SEVERABILITY.  Subject to the provisions of SECTION 12 above, any
provision of this Agreement that is prohibited or unenforceable in any
jurisdiction will, as to such jurisdiction, be ineffective to the extent of such
prohibition or unenforceability without invalidating the remaining provisions
hereof, and any such prohibition or unenforceability in any jurisdiction will
not invalidate or render unenforceable such provision in any other jurisdiction.

         22.  ASSIGNMENT.  This Agreement is personal in its nature and the
parties hereto shall not, without the consent of the other, assign or transfer
this Agreement or any rights or obligations hereunder; PROVIDED, HOWEVER, that
the provisions hereof will inure to the benefit of, and be binding upon, each
successor of the Company, whether by merger, consolidation, transfer of all or
substantially all assets or otherwise.

         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the date first above written.


                          PHARMAVENE, INC.



                          By: /s/ James D. Isbister
                              -----------------------------------
                              James D. Isbister, President


                              /s/ Edward M. Rudnic
                              -----------------------------------
                              Edward M. Rudnic, Ph.D.


                                       -5-

<PAGE>

                              EMPLOYMENT AGREEMENT


         This EMPLOYMENT AGREEMENT, dated as of July 1, 1996 is entered into by
and between PHARMAVENE, INC., a Delaware corporation (the "Company") and James
D. Russo (the "Employee").

         WHEREAS, the Company desires to employ the Employee as Senior Vice
President, Chief Financial Officer of the Company, and the Employee desires to
accept such employment by the Company, on the terms and subject to the
conditions hereinafter set forth.

         NOW, THEREFORE, in consideration of the mutual covenants and
obligations hereinafter set forth, the parties hereto agree as follows:

         1.   EMPLOYMENT.  The Company hereby employs the Employee, and the
Employee hereby accepts employment by the Company, upon the terms and conditions
hereinafter set forth.

         2.   TERM.  Subject to the provisions of SECTIONS 6, 7, 8, and 9 below,
the employment of the Employee hereunder will be for the two-year period
commencing on the date hereof (the "Commencement Date") and ending on the second
anniversary of such Commencement Date.  Unless either party gives written notice
of determination not to renew at least one hundred eighty (180) days prior to
the second anniversary of the Commencement Date, this Agreement shall be renewed
for one (1) year from that anniversary.  Thereafter, unless either party gives
written notice of determination not to renew at least one hundred eighty (180)
days prior to any succeeding anniversary of the Commencement Date, this
Agreement shall be renewed for one (1) year from each anniversary.  The term
"Employment Period" shall mean the two-year period provided for in this
SECTION 2 and any extension thereof, or any shorter period resulting from any
termination of employment under SECTION 6, 7, 8, or 9 below.

         3.   DUTIES AND RESPONSIBILITIES.  The Employee will be employed as
Senior Vice President, Chief Financial Officer of the Company.  The Employee
will perform such duties and services, consistent with his position, as may be
assigned to him from time to time by the Board of Directors or the President of
the Company or the Board's or President's designee.  In furtherance of the
foregoing, the Employee hereby agrees to perform well and faithfully such duties
and responsibilities and the other reasonable duties and responsibilities
assigned to him from time to time by the Board of Directors of the Company or
the President or the Board's or President's designee.

         4.   TIME TO BE DEVOTED TO EMPLOYMENT.  Except for reasonable
vacations, absences due to temporary illness, and activities which have been
mutually agreed to by the parties,  the Employee shall devote substantially all
of his time, attention and energies to the business of the Company during the
Employment Period.  During the Employment Period, the Employee will not be
engaged in any other business activity which, in the reasonable judgment of the
Company, conflicts with the duties of the Employee hereunder, whether or not
such activity is pursued for gain, profit or other pecuniary advantage.

         5.   COMPENSATION; REIMBURSEMENT.  (a)  The Company (or, at the
Company's option, any subsidiary or affiliate thereof) will pay to the Employee
(i) an annual base salary (the "Base Salary") of not less than $153,000.00,
payable in such installments as is the policy of the Company with respect to
employees of the Company at substantially the same employment level as the
Employee.

<PAGE>

         (b)  During the Employment Period, the Employee will be entitled to the
fringe benefits that are made available from time to time to employees of the
Company at substantially the same employment level as the Employee, including
eligibility to participate in any Company stock option or bonus plans.

         (c)  The Company will reimburse the Employee, in accordance with the
practice of the Company from time to time, for all reasonable and necessary
travel expenses and other disbursements incurred by him for or on behalf of the
Company in the performance of his duties hereunder upon presentation by the
Employee to the Company of appropriate vouchers.

         6.   INVOLUNTARY TERMINATION.  If the Employee dies, then the
Employee's employment shall be deemed to terminate on the date of the Employee's
death.  If the Employee is incapacitated or disabled by accident, sickness or
otherwise so as to render him mentally or physically incapable of performing the
services required to be performed by him under this Agreement for a period of
ninety (90) consecutive days or longer, or for ninety (90) days during any six-
month period (such condition being herein referred to as "Disability"), then the
Company, at its option, may terminate the employment of the Employee under this
Agreement immediately upon giving him notice to that effect.  In the case of a
Disability, until the Company shall have terminated the Employee's employment
hereunder in accordance with the foregoing, the Employee will be entitled to
receive compensation, at the rate and in the manner provided in SECTION 5 above,
notwithstanding any such Disability.  Termination pursuant to this SECTION 6 is
hereinafter referred to as an "Involuntary Termination".

         7.   TERMINATION FOR CAUSE.  Upon a vote of the majority of the Board
of Directors or in the discretion of the President of the Company, the Company
may terminate the employment of the Employee hereunder at any time during the
Employment Period for "cause" (such termination being hereinafter referred to as
a "Termination for Cause") by giving the Employee notice of such termination,
whereupon such termination shall take effect immediately.  For the purpose of
this SECTION 7, "cause" will mean (a) the Employee's willful misconduct with
respect to the business and affairs of the Company or any subsidiary or
affiliate thereof, (b) the Employee's neglect of duties or failure to act which
can reasonably be expected to affect materially and adversely the business or
affairs of the Company or any subsidiary or affiliate thereof, (c) the
Employee's material breach of any of the agreements contained in SECTION 3 or 4
hereof, or the Employee's breach of the Proprietary Information and Invention
Agreement referred to in SECTION 11 below, (d) the commission by the Employee of
an act involving moral turpitude relating to the Company or fraud, or (e) the
Employee's conviction of any felony, or of any misdemeanor involving fraud,
theft, embezzlement, forgery or moral turpitude.

         8.   TERMINATION WITHOUT CAUSE.  The Company may terminate the
employment of the Employee hereunder at any time during the Employment Period
without "cause" (such termination being hereinafter referred to as a
"Termination Without Cause") by giving the Employee written notice of such
termination.  Upon the giving of such notice, termination of employment under
this SECTION 8 will take effect immediately.

         9.   VOLUNTARY TERMINATION.  Any termination of the employment of the
Employee hereunder otherwise than as a result of an Involuntary Termination, a
Termination For Cause or a Termination Without Cause will be referred
hereinafter as a "Voluntary Termination."  Following reasonable notice, a
Voluntary Termination will be deemed to be


                                       -2-
<PAGE>

effective upon the date specified in such notice or, in the absence of such
specification, upon the date of the giving of such notice.

         10.  EFFECT OF TERMINATION OF EMPLOYMENT.  (a)  Upon termination of the
Employee's employment hereunder pursuant to a Voluntary Termination or a
Termination For Cause, neither the Employee nor his beneficiary or estate will
have any further rights or claims against the Company under this Agreement
except to receive:


          (i)    the unpaid portion of the Base Salary provided for in
SECTION 5(a) above, computed on a PRO RATA basis to the date of such
termination; and

          (ii)   reimbursement for any expenses for which the Employee shall not
have theretofore been reimbursed as provided in SECTION 5(c) above.

          (iii)  retention in the Company's 401(k) Program and other Company
employee benefits (as required by law) and the opportunity to purchase health
benefits under the Company's health benefits program, as required by COBRA.

         (b)  Upon termination of the Employee's employment hereunder pursuant
to an Involuntary Termination, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to six (6) months' Base
Salary, payable at the same rate and in the same manner as set forth in
SECTION 5 above.

         (c)  Upon termination of the Employee's employment hereunder pursuant
to a Termination Without Cause, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to the lesser of (i) one (1)
year's Base Salary, payable in twelve (12) equal monthly installments or (ii)
nine (9) months' Base Salary or the Base Salary for the then remaining term of
the Employment Period, whichever is greater, in each case payable at the same
rate and in the same manner as set forth in SECTION 5 above.

         11.  PROPRIETARY INFORMATION AND INVENTION AGREEMENT.  The Employee has
executed the Proprietary Information and Invention Agreement, a copy of which is
attached hereto as EXHIBIT A, and covenants that he will comply with the terms
of such Proprietary Information and Invention Agreement during the term thereof.


         12.  ENFORCEMENT.  It is the desire and intent of the parties hereto
that the provisions of this Agreement will be enforced to the fullest extent
permissible under the laws and public policies applied in each jurisdiction in
which enforcement is sought.  Accordingly, to the extent that a restriction
contained in this Agreement is more restrictive than permitted by the laws of
any jurisdiction where this Agreement may be subject to review and
interpretation, the terms of such restriction, for the purpose only of the
operation of such restriction in such jurisdiction, will be the maximum
restriction allowed by the laws of such jurisdiction and such restriction will
be deemed to have been revised accordingly herein.  A court having jurisdiction
over an action arising out of or seeking enforcement of any restriction
contained in this Agreement may modify the terms of such restriction in
accordance with this SECTION 12.

         13.  REMEDIES; SURVIVAL.  (a)  The Employee acknowledges and
understands that the provisions of this Agreement are of a special and unique
nature, the loss of which



                                       -3-
<PAGE>


cannot be accurately compensated for in damages by an action at law, and that
the breach or threatened breach of the provisions of this Agreement would cause
the Company irreparable harm.  In the event of a breach or threatened breach by
the Employee of the provisions of SECTION 11 above, the Company will be entitled
to an injunction restraining him from such breach.  Nothing herein contained
will be construed as prohibiting the Company from pursuing any other remedies
available at law for any breach or threatened breach of this Agreement.

         (b)  Notwithstanding anything contained in this Agreement to the
contrary, the provisions of SECTIONS 11, 12, 14, 15, 16, 20, 21 and this
SECTION 13, will survive the expiration or other termination of this Agreement
until, by their terms, such provisions are no longer operative.


         14.  STOCK OPTIONS.  In the event the Employee is terminated from the
Company or a subsidiary within one (1) year of either of the events specified in
(i) or (ii) below, or the employee's responsibilities or duties are
substantially reduced within one (1) year of either of the events specified in
(i) or (ii) below, all outstanding Stock Options at that date of termination or
date of reduction of responsibilities or duties shall become immediately
exercisable for a period of three (3) months.

          (i)   as a result of or in connection with any tender offer,
                exchange offer, merger or other business combination, sale of
                assets or contested election, or combination of the
                foregoing, the persons who were Directors of the Corporation
                just prior to such event cease to constitute a majority of
                the Corporation's Board of Directors; or

          (ii)  the stockholders of the Corporation approve an agreement
                providing for a transaction in which the Corporation will
                cease to be an independent publicly-owned corporation or a
                sale or other disposition of all or substantially all of the
                assets of the Corporation occurs.

         15.  NOTICES.  All notices, demands and other communications which are
required to be given, served or sent pursuant to this Agreement will be in
writing and will be delivered personally or sent by air courier or first class
certified or registered mail, return receipt requested and postage prepaid,
addressed as follows:

         If to the Employee:

         James D. Russo
          11304 Taffrail Court
         Reston, Virginia  22091

         If to the Company:

         Pharmavene, Inc.
         1550 East Gude Drive
         Rockville, Maryland  20850

         Attention:  President

All notices and other communications given to any party hereto in accordance
with the provisions of this Agreement will be deemed to have been given on the
date of delivery if


                                       -4-
<PAGE>

personally delivered; on the business day after the date when sent if sent by
air courier; and on the third business day after the date when sent if sent by
mail, in each case addressed to such party as provided in this SECTION 14 or in
accordance with the latest unrevoked direction from such party.

         16.  BINDING AGREEMENT; BENEFIT.  The provisions of this Agreement will
be binding upon and will inure to the benefit of, the respective heirs, legal
representatives and successors of the parties hereto.

         17.  GOVERNING LAW.  This Agreement will be governed by, and construed
and enforced in accordance with, the laws of the State of Maryland (not
including the choice of law provisions thereof).

         18.  WAIVER OF BREACH.  The waiver by either party of a breach of any
provision of this Agreement by the other party must be in writing and will not
operate or be construed as a waiver of any subsequent breach by such other
party.

         19.  ENTIRE AGREEMENT; AMENDMENTS.  This Agreement contains the entire
agreement between the parties with respect to the subject matter hereof and
supersedes all prior agreements or understanding among the parties with respect
thereto.  This Agreement may be amended only by an agreement in writing signed
by the parties hereto.

         20.  HEADINGS.  The Section headings contained in this Agreement are
for reference purposes only and will not affect in any way the meaning or
interpretation of this Agreement.

         21.  SEVERABILITY.  Subject to the provisions of SECTION 12 above, any
provision of this Agreement that is prohibited or unenforceable in any
jurisdiction will, as to such jurisdiction, be ineffective to the extent of such
prohibition or unenforceability without invalidating the remaining provisions
hereof, and any such prohibition or unenforceability in any jurisdiction will
not invalidate or render unenforceable such provision in any other jurisdiction.

         22.  ASSIGNMENT.  This Agreement is personal in its nature and the
parties hereto shall not, without the consent of the other, assign or transfer
this Agreement or any rights or obligations hereunder; PROVIDED, HOWEVER, that
the provisions hereof will inure to the benefit of, and be binding upon, each
successor of the Company, whether by merger, consolidation, transfer of all or
substantially all assets or otherwise.

         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the date first above written.


                          PHARMAVENE, INC.



                          By: /s/ James D. Isbister
                              -----------------------------------
                              James D. Isbister, President


                              /s/ James D. Russo
                              -----------------------------------
                              James D. Russo


                                       -5-

<PAGE>

                              EMPLOYMENT AGREEMENT


         This EMPLOYMENT AGREEMENT, dated as of July 1, 1996 is entered into by
and between PHARMAVENE, INC., a Delaware corporation (the "Company") and
Krystyna Belendiuk, Ph.D. (the "Employee").

         WHEREAS, the Company desires to employ the Employee as Senior Vice
President, Business Development of the Company, and the Employee desires to
accept such employment by the Company, on the terms and subject to the
conditions hereinafter set forth.

         NOW, THEREFORE, in consideration of the mutual covenants and
obligations hereinafter set forth, the parties hereto agree as follows:

         1.   EMPLOYMENT.  The Company hereby employs the Employee, and the
Employee hereby accepts employment by the Company, upon the terms and conditions
hereinafter set forth.

         2.   TERM.  Subject to the provisions of SECTIONS 6, 7, 8, and 9 below,
the employment of the Employee hereunder will be for the two-year period
commencing on the date hereof (the "Commencement Date") and ending on the second
anniversary of such Commencement Date.  Unless either party gives written notice
of determination not to renew at least one hundred eighty (180) days prior to
the second anniversary of the Commencement Date, this Agreement shall be renewed
for one (1) year from that anniversary.  Thereafter, unless either party gives
written notice of determination not to renew at least one hundred eighty (180)
days prior to any succeeding anniversary of the Commencement Date, this
Agreement shall be renewed for one (1) year from each anniversary.  The term
"Employment Period" shall mean the two-year period provided for in this
SECTION 2 and any extension thereof, or any shorter period resulting from any
termination of employment under SECTION 6, 7, 8, or 9 below.

         3.   DUTIES AND RESPONSIBILITIES.  The Employee will be employed as
Senior Vice President, Business Development of the Company.  The Employee will
perform such duties and services, consistent with his position, as may be
assigned to him from time to time by the Board of Directors or the President of
the Company or the Board's or President's designee.  In furtherance of the
foregoing, the Employee hereby agrees to perform well and faithfully such duties
and responsibilities and the other reasonable duties and responsibilities
assigned to him from time to time by the Board of Directors of the Company or
the President or the Board's or President's designee.

         4.   TIME TO BE DEVOTED TO EMPLOYMENT.  Except for reasonable
vacations, absences due to temporary illness, and activities which have been
mutually agreed to by the parties,  the Employee shall devote substantially all
of his time, attention and energies to the business of the Company during the
Employment Period.  During the Employment Period, the Employee will not be
engaged in any other business activity which, in the reasonable judgment of the
Company, conflicts with the duties of the Employee hereunder, whether or not
such activity is pursued for gain, profit or other pecuniary advantage.

         5.   COMPENSATION; REIMBURSEMENT.  (a)  The Company (or, at the
Company's option, any subsidiary or affiliate thereof) will pay to the Employee
(i) an annual base salary (the "Base Salary") of not less than $157,317.00,
payable in such installments as is the policy of the Company with respect to
employees of the Company at substantially the same employment level as the
Employee.

<PAGE>

         (b)  During the Employment Period, the Employee will be entitled to the
fringe benefits that are made available from time to time to employees of the
Company at substantially the same employment level as the Employee, including
eligibility to participate in any Company stock option or bonus plans.

         (c)  The Company will reimburse the Employee, in accordance with the
practice of the Company from time to time, for all reasonable and necessary
travel expenses and other disbursements incurred by him for or on behalf of the
Company in the performance of his duties hereunder upon presentation by the
Employee to the Company of appropriate vouchers.

         6.   INVOLUNTARY TERMINATION.  If the Employee dies, then the
Employee's employment shall be deemed to terminate on the date of the Employee's
death.  If the Employee is incapacitated or disabled by accident, sickness or
otherwise so as to render him mentally or physically incapable of performing the
services required to be performed by him under this Agreement for a period of
ninety (90) consecutive days or longer, or for ninety (90) days during any six-
month period (such condition being herein referred to as "Disability"), then the
Company, at its option, may terminate the employment of the Employee under this
Agreement immediately upon giving him notice to that effect.  In the case of a
Disability, until the Company shall have terminated the Employee's employment
hereunder in accordance with the foregoing, the Employee will be entitled to
receive compensation, at the rate and in the manner provided in SECTION 5 above,
notwithstanding any such Disability.  Termination pursuant to this SECTION 6 is
hereinafter referred to as an "Involuntary Termination".

         7.   TERMINATION FOR CAUSE.  Upon a vote of the majority of the Board
of Directors or in the discretion of the President of the Company, the Company
may terminate the employment of the Employee hereunder at any time during the
Employment Period for "cause" (such termination being hereinafter referred to as
a "Termination for Cause") by giving the Employee notice of such termination,
whereupon such termination shall take effect immediately.  For the purpose of
this SECTION 7, "cause" will mean (a) the Employee's willful misconduct with
respect to the business and affairs of the Company or any subsidiary or
affiliate thereof, (b) the Employee's neglect of duties or failure to act which
can reasonably be expected to affect materially and adversely the business or
affairs of the Company or any subsidiary or affiliate thereof, (c) the
Employee's material breach of any of the agreements contained in SECTION 3 or 4
hereof, or the Employee's breach of the Proprietary Information and Invention
Agreement referred to in SECTION 11 below, (d) the commission by the Employee of
an act involving moral turpitude relating to the Company or fraud, or (e) the
Employee's conviction of any felony, or of any misdemeanor involving fraud,
theft, embezzlement, forgery or moral turpitude.

         8.   TERMINATION WITHOUT CAUSE.  The Company may terminate the
employment of the Employee hereunder at any time during the Employment Period
without "cause" (such termination being hereinafter referred to as a
"Termination Without Cause") by giving the Employee written notice of such
termination.  Upon the giving of such notice, termination of employment under
this SECTION 8 will take effect immediately.

         9.   VOLUNTARY TERMINATION.  Any termination of the employment of the
Employee hereunder otherwise than as a result of an Involuntary Termination, a
Termination For Cause or a Termination Without Cause will be referred
hereinafter as a "Voluntary Termination."  Following reasonable notice, a
Voluntary Termination will be deemed to be


                                       -2-
<PAGE>

effective upon the date specified in such notice or, in the absence of such
specification, upon the date of the giving of such notice.

         10.  EFFECT OF TERMINATION OF EMPLOYMENT.  (a)  Upon termination of the
Employee's employment hereunder pursuant to a Voluntary Termination or a
Termination For Cause, neither the Employee nor his beneficiary or estate will
have any further rights or claims against the Company under this Agreement
except to receive:


          (i)    the unpaid portion of the Base Salary provided for in
SECTION 5(a) above, computed on a PRO RATA basis to the date of such
termination; and

          (ii)   reimbursement for any expenses for which the Employee shall not
have theretofore been reimbursed as provided in SECTION 5(c) above.

          (iii)  retention in the Company's 401(k) Program and other Company
employee benefits (as required by law) and the opportunity to purchase health
benefits under the Company's health benefits program, as required by COBRA.

         (b)  Upon termination of the Employee's employment hereunder pursuant
to an Involuntary Termination, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to six (6) months' Base
Salary, payable at the same rate and in the same manner as set forth in
SECTION 5 above.

         (c)  Upon termination of the Employee's employment hereunder pursuant
to a Termination Without Cause, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to the lesser of (i) one (1)
year's Base Salary, payable in twelve (12) equal monthly installments or (ii)
nine (9) months' Base Salary or the Base Salary for the then remaining term of
the Employment Period, whichever is greater, in each case payable at the same
rate and in the same manner as set forth in SECTION 5 above.

         11.  PROPRIETARY INFORMATION AND INVENTION AGREEMENT.  The Employee has
executed the Proprietary Information and Invention Agreement, a copy of which is
attached hereto as EXHIBIT A, and covenants that he will comply with the terms
of such Proprietary Information and Invention Agreement during the term thereof.


         12.  ENFORCEMENT.  It is the desire and intent of the parties hereto
that the provisions of this Agreement will be enforced to the fullest extent
permissible under the laws and public policies applied in each jurisdiction in
which enforcement is sought.  Accordingly, to the extent that a restriction
contained in this Agreement is more restrictive than permitted by the laws of
any jurisdiction where this Agreement may be subject to review and
interpretation, the terms of such restriction, for the purpose only of the
operation of such restriction in such jurisdiction, will be the maximum
restriction allowed by the laws of such jurisdiction and such restriction will
be deemed to have been revised accordingly herein.  A court having jurisdiction
over an action arising out of or seeking enforcement of any restriction
contained in this Agreement may modify the terms of such restriction in
accordance with this SECTION 12.

         13.  REMEDIES; SURVIVAL.  (a)  The Employee acknowledges and
understands that the provisions of this Agreement are of a special and unique
nature, the loss of which


                                       -3-

<PAGE>

cannot be accurately compensated for in damages by an action at law, and that
the breach or threatened breach of the provisions of this Agreement would cause
the Company irreparable harm.  In the event of a breach or threatened breach by
the Employee of the provisions of SECTION 11 above, the Company will be entitled
to an injunction restraining him from such breach.  Nothing herein contained
will be construed as prohibiting the Company from pursuing any other remedies
available at law for any breach or threatened breach of this Agreement.

         (b)  Notwithstanding anything contained in this Agreement to the
contrary, the provisions of SECTIONS 11, 12, 14, 15, 16, 20, 21 and this
SECTION 13, will survive the expiration or other termination of this Agreement
until, by their terms, such provisions are no longer operative.


         14.  STOCK OPTIONS.  In the event the Employee is terminated from the
Company or a subsidiary within one (1) year of either of the events specified in
(i) or (ii) below, or the employee's responsibilities or duties are
substantially reduced within one (1) year of either of the events specified in
(i) or (ii) below, all outstanding Stock Options at that date of termination or
date of reduction of responsibilities or duties shall become immediately
exercisable for a period of three (3) months.

          (i)   as a result of or in connection with any tender offer,
                exchange offer, merger or other business combination, sale of
                assets or contested election, or combination of the
                foregoing, the persons who were Directors of the Corporation
                just prior to such event cease to constitute a majority of
                the Corporation's Board of Directors; or

          (ii)  the stockholders of the Corporation approve an agreement
                providing for a transaction in which the Corporation will
                cease to be an independent publicly-owned corporation or a
                sale or other disposition of all or substantially all of the
                assets of the Corporation occurs.

         15.  NOTICES.  All notices, demands and other communications which are
required to be given, served or sent pursuant to this Agreement will be in
writing and will be delivered personally or sent by air courier or first class
certified or registered mail, return receipt requested and postage prepaid,
addressed as follows:

         If to the Employee:

         Krystyna Belendiuk, Ph.D.
          11208 Tara Road
         Potomac, Maryland  20854

         If to the Company:

         Pharmavene, Inc.
         1550 East Gude Drive
         Rockville, Maryland  20850

         Attention:  President

All notices and other communications given to any party hereto in accordance
with the provisions of this Agreement will be deemed to have been given on the
date of delivery if


                                       -4-
<PAGE>

personally delivered; on the business day after the date when sent if sent by
air courier; and on the third business day after the date when sent if sent by
mail, in each case addressed to such party as provided in this SECTION 14 or in
accordance with the latest unrevoked direction from such party.

         16.  BINDING AGREEMENT; BENEFIT.  The provisions of this Agreement will
be binding upon and will inure to the benefit of, the respective heirs, legal
representatives and successors of the parties hereto.

         17.  GOVERNING LAW.  This Agreement will be governed by, and construed
and enforced in accordance with, the laws of the State of Maryland (not
including the choice of law provisions thereof).

         18.  WAIVER OF BREACH.  The waiver by either party of a breach of any
provision of this Agreement by the other party must be in writing and will not
operate or be construed as a waiver of any subsequent breach by such other
party.

         19.  ENTIRE AGREEMENT; AMENDMENTS.  This Agreement contains the entire
agreement between the parties with respect to the subject matter hereof and
supersedes all prior agreements or understanding among the parties with respect
thereto.  This Agreement may be amended only by an agreement in writing signed
by the parties hereto.

         20.  HEADINGS.  The Section headings contained in this Agreement are
for reference purposes only and will not affect in any way the meaning or
interpretation of this Agreement.

         21.  SEVERABILITY.  Subject to the provisions of SECTION 12 above, any
provision of this Agreement that is prohibited or unenforceable in any
jurisdiction will, as to such jurisdiction, be ineffective to the extent of such
prohibition or unenforceability without invalidating the remaining provisions
hereof, and any such prohibition or unenforceability in any jurisdiction will
not invalidate or render unenforceable such provision in any other jurisdiction.

         22.  ASSIGNMENT.  This Agreement is personal in its nature and the
parties hereto shall not, without the consent of the other, assign or transfer
this Agreement or any rights or obligations hereunder; PROVIDED, HOWEVER, that
the provisions hereof will inure to the benefit of, and be binding upon, each
successor of the Company, whether by merger, consolidation, transfer of all or
substantially all assets or otherwise.

         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the date first above written.


                          PHARMAVENE, INC.



                          By: /s/ James D. Isbister
                              -----------------------------------
                              James D. Isbister, President


                              /s/ Krystyna Belendiuk
                              -----------------------------------
                              Krystyna Belendiuk, Ph.D.


                                       -5-

<PAGE>

                          CONTINUING SERVICES AGREEMENT

          This CONTINUING SERVICES AGREEMENT is entered into as of this 1st
day of July, 1996 by and among Pharmavene, Inc., a Delaware corporation with
offices located at 1550 East Gude Drive, Rockville, Maryland  20850 (the
"Company"), and James D. Isbister, an individual residing at 9521 Accord Drive,
Potomac, Maryland  20854 (the "Employee").

          WHEREAS, the Employee is a party to an Employment Agreement between
the Company and the Employee dated as of December 12, 1995 (the "Employment
Agreement") which provides for the Employee's employment as the President and
Chief Executive Officer of the Company;

          WHEREAS, the Employee has resigned his position as President of the
Company effective July 1, 1996; and

          WHEREAS, the Employee also serves as the Chairman of the Board of
Directors of the Company.

          WHEREAS, the Company and the Employee wish to set forth in writing the
terms and conditions upon which the Employee will continue to provide certain
services to the Company in the event of his "Voluntary Termination" (as such
term is defined in the Employment Agreement) as Chief Executive Officer of the
Company.

          NOW, THEREFORE, in consideration of the foregoing and the mutual
promises and agreements contained herein, the Company and the Employee agree as
follows:

          1.   APPLICABILITY OF THE EMPLOYMENT AGREEMENT.  The Employee will
continue to be employed as the Company's Chief Executive Officer pursuant to the
terms of the Employment Agreement until such time as his employment as Chief
Executive Officer is terminated in accordance with the terms and conditions
contained in the Employment Agreement.  Until the Employee's employment as Chief
Executive Officer is terminated in accordance with the terms of the Employment
Agreement, the terms of the Employment Agreement shall remain in full force and
shall be applicable to the Employee, unless such Employment Agreement is amended
or modified after the date hereof by written agreement of the parties thereto.

          2.   TERMINATION OF EMPLOYMENT; CONTINUATION OF SERVICE AS CHAIRMAN OF
THE BOARD.  In the event of the Employee's Voluntary Termination as Chief
Executive Officer of the Company on or before December 31, 1998 in accordance
with the terms of SECTION 9 of the Employment Agreement, the Employee shall
thereafter and through December 31, 1998 (or such later date as the Company and
the Employee may agree) remain in the employ of the Company as the Chairman of
the Board of Directors.  For so long as the Employee continues to serve as
Chairman of the Board of Directors, he shall be deemed an "employee" of the
Company for all purposes.  As Chairman of the Board of Directors, the Employee
shall perform such duties and services as are consistent with his position, and
agrees to perform well and faithfully such duties and responsibilities.


<PAGE>

          3.   COMPENSATION OF THE EMPLOYEE.  In the event of the Employee's
Voluntary Termination as Chief Executive Officer on or before December 31, 1998,
the Company will pay to the Employee an annual base salary of $65,000,
commencing on the day following the Employee's resignation as Chief Executive
Officer, and payable in such installments as is the policy of the Company with
respect to employees of the Company at substantially the same employment level
as the Employee.  In the event of the Employee's Voluntary Termination as Chief
Executive Officer on or before December 31, 1996, the Employee will be eligible
to receive a bonus in respect of the Company's fiscal year ended December 31,
1996, pro rated based on the number of full months in such year that the
Employee was employed as Chief Executive Officer.  Such bonus shall be awarded
in accordance with the Company's regular policies and procedures for awarding
bonuses to employees.

          4.   OTHER BENEFITS.  Upon the Employee's Voluntary Termination as
Chief Executive Officer, and for so long as the Employee remains in the employ
of the Company as Chairman of the Board of Directors, the Employee shall
continue to be eligible to receive health insurance coverage pursuant to the
Company's group health insurance plans or programs for its employees, on the
same terms as are made available to the senior executive officers of the
Company.  In addition, for so long as the Employee remains in the employ of the
Company as Chairman of the Board of Directors, the Company will reimburse the
Employee, in accordance with the practice of the Company from time to time, for
all reasonable and necessary travel expenses and other disbursements incurred by
him for or on behalf of the Company in the performance of his duties hereunder
upon presentation by the Employee to the Company of appropriate vouchers.

          5.   STOCK OPTIONS.  Upon the Employee's Voluntary Termination as
Chief Executive Officer, all options to purchase the Company's common stock
previously granted to the Employee shall remain outstanding and shall continue
to vest for so long as the Employee remains in the employ of the Company as
Chairman of the Board of Directors, in accordance with the terms and provisions
of the Company's Stock Option Plan and the stock option agreements entered into
between the Company and the Employee as if such Voluntary Termination had not
occurred.  In addition, notwithstanding any provision to the contrary in the
Company's Stock Option Plan or any stock option agreement, all stock options
held by the Employee will vest and become exercisable immediately in the event
of the Employee's death or disability.

          6.   PROPRIETARY INFORMATION AND NONCOMPETITION AGREEMENT.  The
Employee has executed a Proprietary Information and Noncompetition Agreement and
covenants that he will continue to comply with the terms of such agreement
during the term thereof.

          7.   SURVIVAL.  Notwithstanding anything contained in this Agreement
to the contrary, the provisions of SECTIONS 5, 6, 8, 10, 14, 15 and this SECTION
7 will survive the expiration or other termination of this Agreement until, by
their terms, such provisions are no longer operative.

          8.   NOTICES.  All notices, demands and other communications which are
required to be given, served or sent pursuant to this Agreement will be in
writing and will be


                                       -2-
<PAGE>

delivered personally or sent by air courier or first class certified or
registered mail, return receipt requested and postage prepaid, addressed as
follows:

          If to the Employee:

          James D. Isbister
          9521 Accord Drive
          Potomac, Maryland 20854

          If to the Company:

          Pharmavene, Inc.
          1550 East Gude Drive
          Rockville, Maryland 20850
          Attention:  Secretary

All notices and other communications given to any party hereto in accordance
with the provisions of this Agreement will be deemed to have been given on the
date of delivery if personally delivered; on the business day after the date
when sent if sent by air courier; and on the third business day after the date
when sent if sent by mail, in each case addressed to such party as provided in
this SECTION 8 or in accordance with the latest unrevoked direction from such
party.

          9.   BINDING AGREEMENT; BENEFIT.  The provisions of this Agreement
will be binding upon and will inure to the benefit of, the respective heirs,
legal representatives and successors of the parties hereto.

          10.  GOVERNING LAW.  This Agreement will be governed by, and construed
and enforced in accordance with, the laws of the State of Maryland (not
including the choice of law provisions thereof).

          11.  WAIVER OF BREACH.  The waiver by either party of a breach of any
provision of this Agreement by the other party must be in writing and will not
operate or be construed as a waiver of any subsequent breach by such other
party.

          12.  AMENDMENTS.  This Agreement may be amended only by an agreement
in writing signed by the parties hereto.

          13.  HEADINGS.  The section headings contained in this Agreement are
for reference purposes only and will not affect in any way the meaning or
interpretation of this Agreement.

          14.  SEVERABILITY.  Subject to the provisions of SECTION 7 above, any
provision of this Agreement that is prohibited or unenforceable in any
jurisdiction will, as to such jurisdiction, be ineffective to the extent of such
prohibition or unenforceability without


                                       -3-
<PAGE>

invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction will not invalidate or render unenforceable
such provision in any other jurisdiction.

          15.  ASSIGNMENT.  This Agreement is personal in its nature and the
parties hereto shall not, without the consent of the other, assign or transfer
this Agreement or any rights or obligations hereunder; PROVIDED, HOWEVER, that
the provisions hereof will inure to the benefit of, and be binding upon, each
successor of the Company, whether by merger, consolidation, transfer of all or
substantially all assets or otherwise.

          IN WITNESS WHEREOF, each of the parties hereto has duly executed this
Continuing Services Agreement as of the day and year first above written.

                              PHARMAVENE, INC.



                              By:
                                 ------------------------------------------
                                    Name:
                                    Title:



                              James D. Isbister


                              ---------------------------------------------


                                       -4-


<PAGE>
                               AMENDMENT NO. 2 TO
                      CONVERSION AND SUBSCRIPTION AGREEMENT



          THIS AMENDMENT NO. 2 (the "Amendment") to the CONVERSION AND
SUBSCRIPTION AGREEMENT (the "Agreement") is made and entered into as of
December ___, 1995, by and among Pharmavene, Inc., a Delaware corporation (the
"Borrower"), and the persons or entities listed on the signature pages hereof,
each of whom (each, a "Lender," and collectively, the "Lenders") is a party to
that certain credit agreement, dated May 3, 1994, by and among the Borrower and
the Lenders (the "Credit Agreement").  This Amendment No. 2 to the Credit
Agreement supersedes Amendment No. 1 to the Credit Agreement, which hereafter
shall have no force or effect.  Capitalized terms used herein that are defined
in the Agreement and the Credit Agreement shall have the respective meanings set
forth in the Agreement and the Credit Agreement, as applicable, unless otherwise
defined herein.

          WHEREAS, pursuant to the terms of Section 2 of the Agreement, the
Conversion Price shall be adjusted from $1.25 per share to $0.75 per share in
the event certain events have not occurred on or before December 31, 1995; and

          WHEREAS, the parties hereto wish to amend the Agreement as among 
such parties to extend the date by which an initial public offering of shares 
of Borrower's common stock may occur, without causing an adjustment of the 
Conversion Price, to February 28, 1996. NOW, THEREFORE, it is agreed by and 
among each of the parties hereto as follows:

          1.   AMENDMENT OF SECTION 2.  Section 2 of the Agreement is hereby
amended by deleting such section in its entirety and replacing it with the
following:

               "2.  CONVERSION PRICE ADJUSTMENT.  If the Borrower has not
consummated: (i) on or before February 28, 1996, a public offering and sale of
equity securities of the Borrower with gross proceeds of at least ten million
dollars ($10,000,000), (ii) on or before December 31, 1995, the consolidation or
merger of the Borrower with or into another entity (other than a consolidation
or merger in which the Borrower is the surviving corporation) or the sale of
substantially all of the assets of the Borrower or (iii) on or before December
31, 1995, a strategic alliance, corporate partnering arrangement, or licensing,
co-promotion or other agreement pursuant to which the Borrower receives or is
guaranteed to receive at least fifteen million dollars ($15,000,000), then, on
February 28, 1996, the Conversion Price shall be adjusted from $1.25 per share
to seventy-five cents ($.75) per share, and each Lender shall be entitled to
receive from the Borrower on such date a number of Adjustment Shares equal to
the number of shares of Series A Stock such Lender would have received if the
Conversion Price had been $.75 per share on the Conversion Date, less the
Initial Shares issued to such Lender."

<PAGE>

          2.   MISCELLANEOUS.

               2.01 GOVERNING LAW.  This Amendment shall be governed by and
construed in accordance with the laws of the State of Maryland (excluding choice
of law provisions).

               2.02 EFFECT ON AGREEMENT AND CREDIT AGREEMENT.  This Amendment
amends the Agreement and the Credit Agreement and shall be deemed to supersede
any and all terms of the Credit Agreement that are inconsistent herewith.

               2.03 ASSIGNMENT.  This Amendment shall not be assignable by any
party to any person, other than a successor entity.

          IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed on their behalf as of the date first above written.

                              PHARMAVENE, INC.


                              By:
                                 -------------------------------------
                                 Name:  James D. Isbister
                                 Title:  President

                              HEALTHCARE VENTURES III, L.P.

                              By Healthcare Partners III, L.P., as
                                 General Partner


                              By:
                                 -------------------------------------
                                 Name:
                                 Title:  General Partner

                              HEALTHCARE VENTURES IV, L.P.

                              By Healthcare Partners IV, L.P., as
                                 General Partner


                              By:
                                 -------------------------------------
                                 Name:
                                 Title:  General Partner

<PAGE>

                              STATE TREASURER OF THE STATE OF
                                MICHIGAN
                                 Custodian of the Michigan Public
                                 School Employees' Retirement System,
                                 State Employees' Retirement System,
                                 Michigan State Police Retirement
                                 System and Michigan Judges Retirement
                                 System


                              By:
                                 -------------------------------------
                                 Name:
                                 Title:

                              THE AETNA CASUALTY AND SURETY
                                 COMPANY

                              By:
                                 -------------------------------------
                                 Name:
                                 Title:

                              EVEREST TRUST


                              By:
                                 -------------------------------------
                                 Name:
                                 Title:


                              HUDSON TRUST


                              By:
                                 -------------------------------------
                                 Name:
                                 Title:



<PAGE>

                         CONSENT AND AGREEMENT TO AMEND



     The undersigned, as holders (the "Holders") of shares of Series A
Convertible Preferred Stock ("Series A Preferred Stock") of Pharmavene, Inc., a
Delaware corporation (the "Corporation"), hereby agree with the Corporation as
follows:

     WHEREAS, the Corporation and the Holders have entered into a Third Amended
and Restated Stockholders' Agreement, dated as of June 1, 1993 and amended on
September 29, 1993, January 31, 1994 and May 22, 1995 (the "Stockholders'
Agreement");

     WHEREAS, the Corporation proposes to issue shares of its Common Stock, $.01
par value ("Common Stock") in an underwritten public offering (the "Initial
Public Offering") pursuant to a Registration Statement on Form S-1
("Registration Statement"); and

     WHEREAS, the Holders have certain registration rights, rights of first
offer and other rights in the Stockholders' Agreement;

     NOW, THEREFORE, the Corporation and the Holders agree as follows:

     1.   The Corporation and each of the Holders hereby agree that Section 1
DEFINITIONS of the Stockholders' Agreement be amended as follows:

          (a)  The definition of "Transfer" shall be amended in its entirety to
     read as follows:

               "TRANSFER shall include any disposition of any Restricted
     Securities or of any interest therein which would either constitute a sale
     within the meaning of the Securities Act or be exempt from the registration
     requirements of the Securities Act."


          (b)  The following shall be added to as a new definition as follows:

                    "Initial Public Offering" shall mean the offer and sale of
     Common Stock of the Corporation pursuant to the Registration Statement
     filed with the Securities and Exchange Commission on October 27, 1995, as
     amended from time to time."


     2.   In connection with the Initial Public Offering, each of the Holders
hereby waives, effective as of the date hereof, (i) the observance of the right
of first refusal specified in Section 2.3 RIGHT OF FIRST REFUSAL of the
Stockholders' Agreement with respect to the shares of Common Stock to be issued
in the Initial Public Offering, including the right to receive prior notice of
the Initial Public Offering pursuant to Section 2.3(b), (ii) the right to
receive notice of the filing of the Registration Statement specified in Section
4 of the Stockholders' Agreement, and (iii) the right to receive notice pursuant
to the provisions of Article III, Section A.6(c) of the Corporation's Fourth
Restated Certificate of Incorporation (the "Certificate") in connection with


<PAGE>

any required approval of the Initial Public Offering and in connection with the
issuance of 75,000 warrants to purchase the Corporation's Common Stock to
certain holders of Series A Preferred Stock in connection with a loan
commitment.

     3.   The Corporation and each of the Holders hereby agree that Section
2.4(b) STOCK AND OPTION AGREEMENTS of the Stockholders' Agreement be amended,
effective as of the date hereof, so that the maximum number of options issuable
by the Corporation pursuant to its 1991 Stock Option Plan (the "Stock Option
Plan") be increased 1,800,000 shares (after giving effect to a one-for-four
reverse stock split).  Each of the Holders hereby further waives any notice
requirements contained in Article III, Section A.6(c) of the Certificate in
connection with the approval of the foregoing amendment to Section 3a. of the
Stock Option Plan.

     4.   The Corporation and each of the Holders hereby agree that the Section
3.4 REQUIRED REGISTRATION of the Stockholders' Agreement be amended to include
an additional Section 3.4(c) as follows:

          "(c) Anything contained herein to the contrary notwithstanding, the
     Corporation shall not be obligated to cause to become effective a
     registration statement under the Securities Act pursuant to this Section
     3.4 until a date no sooner than six months from the effective date of the
     Registration Statement filed by the Corporation in connection with its
     Initial Public Offering."

     5.   The Corporation and each of the Holders hereby agree that Section 3.5
PIGGYBACK REGISTRATION of the Stockholders' Agreement shall be amended to add a
new sentence as the last sentence of paragraph (a):

     "The rights granted under this section, including the right to receive
     notice pursuant hereto, shall not apply to the Initial Public Offering."


     6.   The Corporation and each of the Holders hereby agree that Section 7
DURATION OF THE AGREEMENT of the Stockholders' Agreement be amended in its
entirety to read as follows:

          "7.  DURATION OF AGREEMENT.  The rights and obligations of the
     Corporation and each Investor set forth in Section 2 hereof, other than the
     rights and obligations set forth in Section 2.5 hereof, shall terminate
     simultaneously with the closing of the Initial Public Offering.  Otherwise,
     the rights and obligations of the Corporation and each Investor set forth
     herein survive indefinitely until, by their respective terms, they are no
     longer applicable."


     7.   (a)  Each of the Holders hereby agrees that upon the closing of the
Initial Public Offering, each warrant to purchase Series A Preferred Stock (the
"Series A Warrants") will represent the right to receive the number of shares of
Common Stock into which the shares of Series A Preferred Stock issuable upon
exercise of the Series A Warrant would have been


                                       -2-
<PAGE>

converted if it had been exercised immediately prior to the closing of the
Initial Public Offering. Each Holder further agrees that promptly following the
closing of the Initial Public Offering, such Holder will deliver to the
Corporation any Series A Warrants which were issued to it in order to exchange
such Series A Warrants for a like number of warrants to purchase shares of the
Corporation's Common Stock.

          (b)  The obligations set forth in Section 7(a) hereunder shall bind
any assignee or transferee of any part of such Holder's right, title and
interest in and under the Series A Preferred Stock and the Series A Warrants,
and such Holder agrees to require any assignee or transferee, as a precondition
to such assignment or other transfer, to confirm in writing to the Corporation
that it will abide by the terms of Section 7 of this Agreement as if it were to
party hereto.

     This Consent and Agreement to Amend (the"Agreement") may be executed in two
or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument.  This Agreement
will be binding upon the Corporation and the Holders and their respective
successors, assigns, heirs and personal representatives.

     Except as otherwise provided herein, this agreement shall be effective
immediately prior to the closing of the Initial Public Offering referred to
herein.

     IN WITNESS HEREOF, the parties have executed this agreement as of November
30, 1995.

                              PHARMAVENE, INC.


                              By:  ____________________________________
                                   James D. Isbister
                                   President


HOLDERS OF THE SERIES A PREFERRED STOCK:

          NAME

HEALTHCARE VENTURES II, L.P.


By:  ________________________________________
     Name:
     Title:


                                       -3-
<PAGE>

HEALTHCARE VENTURES III, L.P.


By:  _________________________________________
     Name:
     Title:


HEALTHCARE VENTURES IV, L.P.


By:  __________________________________________
     Name:
     Title:


EVEREST TRUST


By:  _________________________________________
     Name:
     Title:


HUDSON TRUST


By:  __________________________________________
     Name:
     Title:


     __________________________________________
     Lawrence Abrams


ESTATE OF NORNA SAROFIM


By:  __________________________________________
     Name:
     Title:


                                       -4-
<PAGE>

CASTY CHILDREN'S TRUST


By:  __________________________________________
     Trustee


THE AETNA CASUALTY AND SURETY COMPANY


By:  ___________________________________________
     Name:
     Title:


STATE TREASURER OF THE STATE OF MICHIGAN,
     Custodian of the Michigan Public Schools
     Employees' Retirement System, State Employees'
     Retirement System, Michigan State Police
     Retirement System, and Michigan Judges
     Retirement System


By:  ___________________________________________
     Name:
     Title:


                                      -5-


<PAGE>

                                                                   EXHIBIT 10.25

Portions of this Exhibit have been omitted pursuant to a request for
confidential treatment.  The omitted portions, marked by [****], have been
separately filed with the Commission.


                                    AGREEMENT

     This agreement is made on the 28th day of May, 1996 between The P.F.
Laboratories, Inc. whose registered office is situated at 700 Union Blvd.,
Totowa, New Jersey (hereinafter called "P.F. Labs" of the one part) and
Pharmavene, Inc. whose registered office is situated at 1550 East Gude Drive,
Rockville, Maryland (hereinafter called "the Company") of the other part.

     WHEREAS Company shall supply to P.F. Labs bulk carbamazepine in 3 different
forms [****], and WHEREAS P.F. Labs shall encapsulate, bottle and package the
carbamazepine.

     NOW IT IS HEREBY AGREED AND DECLARED as follows:

1.   DEFINITIONS

     In this Agreement unless the context does not so permit the following words
and expressions shall have the following meanings:

     "Affiliate"         means any company controlling, controlled by or in 
                         common control with the company in question (control 
                         being the ownership interest of greater than 50% of the
                         voting shares or interest)

     "Contract Year"     means a consecutive period of twelve months commencing 
                         with the date or anniversary of this Agreement

     "Ingredients"       means bulk carbamazepine supplied by the Company in any
                         one or more of 3 different forms, whether such forms 
                         are separate or combined.

     "Product
     Specifications"     means the labeling and packaging specifications for the
                         Products as set forth in Schedule 2 attached hereto and


<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

                         made a part hereof and as amended from time to time by
                         mutual agreement of P.F. Labs and the Company in 
                         writing

     "Product(s)"        means the capsule form of carbamazepine meeting Product
                         Specifications

     "Calendar Quarter"  means each three calendar month period commencing on 
                         1st January, 1st April, 1st July and 1st October in 
                         each year

     "the Territory"     means the United States of America, including its
                         commonwealths, territories and possessions

2.   COMMENCEMENT AND DURATION

     This Agreement shall commence on the date hereof and, unless sooner
terminated as set forth in this Agreement, shall continue [****]; provided that
the Company may terminate this Agreement upon [****] prior written notice to
P.F. Labs given at any time after the [****] anniversary of the date on which
P.F. Labs has begun, as set forth hereunder, to supply Products for market
introduction in the United States."

3.   SUPPLY OF THE PRODUCT

     Subject to the provisions of this Agreement and effective with the first
order placed by the Company following the initial estimate of commercial
requirements for Products provided by the Company under Section 4(a), the
Company shall purchase and P.F. Labs shall supply the Company's requirements for
Products for sale in the Territory in accordance with Schedule 1, attached and
made a part hereof.


                                        2
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

4.   FORECASTS

          (a)  Three (3) months prior to each Calendar Quarter Company will
     provide P.F. Labs with a written forecast as follows:

               (i)   A fully binding estimate for quantities of Products to be
          purchased by Company and supplied by P.F. Labs during said Calendar
          Quarter, with anticipated delivery dates, sizes strengths and ultimate
          destinations as well as other relevant manufacturing and delivery
          information

               (ii)  An estimate of the quantities of Product, required during
          the next Calendar Quarter, [****]; and

               (iii) A non-binding estimate of Product required for the
          third and fourth Calendar Quarters of such forecast.

          (b)  Each subsequent written forecast shall update the prior estimate
     and include an estimate of requirements for the next additional Calendar
     Quarter, so that estimates for a rolling one-year period are always
     provided.

          (c)  On receipt of the Company's written estimate, unless otherwise
     agreed in writing between the parties, P.F. Labs shall obtain all packaging
     materials required for the manufacture and packaging of the quantity of the
     Products stated in such written estimate.  Ingredients and capsule shells
     will be provided by the Company to P.F. Labs in sufficient time and
     quantity to permit P.F. Labs to carry out its obligations under this
     Agreement.

          (d)  P.F. Labs shall use all reasonable endeavors to supply the
     Company's requirements but shall be under no obligation to supply
     quantities of the Products which are [****] above the binding estimate for
     that Calendar Quarter.  Any greater amount shall be by mutual written
     agreement.


                                        3
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

5.   ORDERS

          (a)  All orders placed by the Company in respect of the Products shall
     be made in writing and sent to P.F. Labs at the aforestated address and
     shall specify the delivery, date, strengths, quantities, and destination as
     well as other relevant information.

          (b)  All orders placed by the Company for the Products shall be of the
     minimum batch size of [****], packaged in bottles [****] or multiples
     thereof for each strength of Product specified in Schedule 1 hereto.

          (c)  Unless otherwise agreed in writing between the parties, the
     Company shall during the period of the Agreement purchase from P.F. Labs in
     each Contract Year all of its requirements for the Products in the
     Territory.

          (d)  The delivery date specified in a purchase order will allow a
     minimum lead time of 60 days from the date of receipt by P.F. Labs of such
     purchase order supplied in accordance with Clause 5(a) hereof and shall
     take into consideration P.F. labs production rate of  [****] or [****],
     provided that nothing in this paragraph shall limit P.F. Labs obligation to
     supply as set forth in Clause 3.

6.   DELIVERY AND INVOICING

          (a)  Delivery of each order of the Products shall be ex P.F. Labs
     manufacturing plant.

          (b)  Where P.F. Labs, at the request of the Company, arranges any
     carriage or insurance of any consignment on the Company's behalf, the
     Company shall pay to P.F. Labs the cost of such carriage and all insurance
     premiums in the manner described in Clause 9 hereof and shall indemnify
     P.F. Labs against all losses, expenses, claims, and liabilities arising
     from such carriage except those caused by the negligence or willful
     misconduct of P.F. Labs.


                                        4
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

7.   PASSING OF TITLE

     Title and risk in the Product shall pass to the Company on delivery at P.F.
Labs' manufacturing plant of the Product to a common carrier selected by the
Company.

8.   PRICE

          (a)  The initial price for the Products shall be that set out in the
     column of Schedule 1 hereto.

          (b)  Notwithstanding Sub-clause 8(a) above, at the end of each full
     Contract Year P.F. Labs may revise the price to be charged for the Product
     to reflect reasonable changes in the cost of packaging and labeling
     Product.  P.F. Labs shall give three months notice and written
     justification of any price increase.  In no case shall the increase be
     greater than the all Cities Consumer Price Index for that year.  In the
     event Company determines, in its sole discretion, that a new price is
     uneconomical, the Company may terminate this Agreement on [****] written
     notice.

          (c)  P.F. Labs may increase the price to be charged for the Products
     at any time to cover any additional expenses incurred by P.F. Labs as a
     result of material amendments by the Company to the Product Specifications.

          (d)  If the process for manufacture of the Product improves by the use
     of more efficient machinery P.F. Labs will reduce the price charged to
     reflect this improvement, but also taking into account the initial cost and
     upkeep of such machinery.

9.   PAYMENT

          (a)  The Company will pay each invoice received from P.F. Labs net 30
     days following the receipt of the invoice.  Payment for each invoice shall
     be made to P.F. Labs by the Company in United States dollars.


                                        5
<PAGE>

          (b)  If any payment remains outstanding 14 days after becoming due
     interest shall be charged at the rate of 1% per annum above the prime rate
     charged by Citibank of New York to its customers until payment is made in
     full to P.F. Labs.

          (c)  If any payment remains outstanding after becoming due under this
     Agreement P.F. Labs may suspend deliveries of any orders of Products made
     pursuant to this Agreement until such time as such outstanding payment has
     been made.

10.  WARRANTIES

          (a)  P.F. Labs hereby warrants that the Products supplied hereunder
     shall comply with the Product Specifications on delivery but P.F. Labs
     liability for breach of this Warranty shall be limited, at the Company's
     option, either to replacing the defective quantities in question or
     refunding to the Company the price of the said defective quantities.

          (b)  P.F. Labs hereby warrants that Products supplied hereunder shall
     be manufactured under current good manufacturing practice regulations and
     applicable sections of the Federal Food, Drug and cosmetic Act and
     regulations thereunder.

          (c)  SUBJECT TO THE PROVISION OF SUB-CLAUSES 10(a) AND 10(b) ABOVE,
     ALL CONDITIONS AND WARRANTIES EXPRESSED OR IMPLIED, STATUTORY OR OTHERWISE,
     AS TO THE QUALITY OR FITNESS OF THE PRODUCTS ARE HEREBY EXCLUDED.  NEITHER
     P.F. LABS NOR THE COMPANY SHALL HAVE ANY LIABILITY TO THE OTHER UNDER THIS
     AGREEMENT FOR ANY PUNITIVE OR EXEMPLARY DAMAGES.

          (d)  The Company shall be entitled to reject any quantities of the
     Products in an Order delivered to it which do not comply with the Product
     Specifications provided that written notice of such rejection is received
     by P.F. Labs within 30 days from delivery of the order to the Company or
     its nominees; provided always that if such non-compliance in the Products
     could not have been identified by reasonable examination of the Products
     the Company shall be entitled to give such notice within 30 days of the
     date when such non-compliance could first have been reasonably identified
     by the Company but not greater


                                        6
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

     than [****] from delivery of the order to the Company or it nominees.  If
     no such notice is received by P.F. Labs within such period the Company
     shall be deemed to have accepted the Products.

11.  PACKAGING AND PRODUCT SPECIFICATIONS - WARRANTY

          (a)  The Company warrants that the Ingredients and the Product
     Specifications, including the statements, declarations and printed
     packaging materials to be affixed to or packaged with the Products, conform
     in all material respects with all applicable government statutes and
     regulations for the lawful and safe shipping, handling, storage and use of
     the Ingredients and Products in the Territory.

          (b)  The Company warrants that the Product Specification is complete
     and accurate and that the Ingredients and the Product Specifications are
     sufficient to enable P.F. Labs to safely manufacture the Products, and that
     both conform in all material respects with all applicable sections of the
     Federal Food, Drug and Cosmetic Act and regulations thereunder.

12.  INDEMNIFICATION

          (a)  P.F. Labs shall indemnify, defend and hold harmless the Company,
     its officers, directors and employees against any and all proven claims,
     losses, damages and liabilities (including reasonable legal costs) incurred
     by the Company to third parties to the extent that any such claim, loss,
     damage or liability solely and directly results from or arises out of any
     act or omission of P.F. Labs, its employees, contractors or agents, which
     is in violation of any law or regulation relative to this Agreement or in
     violation of the terms of this Agreement; provided that P.F. Labs shall
     have no liability for any Product that does not meet the Product
     Specifications as a result of defects in materials supplied by Company or
     Process Equipment at Niro Inc. or because the Product Specifications or
     other information provided by the Company are proven to be inaccurate.


                                        7
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

          (b)  The Company shall indemnify, defend and hold harmless P.F. Labs,
     its officers, directors and employees against any and all proven claims,
     losses, damages and liabilities (including reasonable legal costs) incurred
     by P.F. Labs to third parties to the extent that any such claim, loss,
     damage or liability directly results from or arises out of any act or
     omission of the Company, its employees, contractors or agents, which is in
     violation of any law or regulation relative to this Agreement, or in
     violation of the terms of this Agreement.

          (c)  Each party shall promptly notify the other of any claims subject
     to indemnification. The indemnifying party shall have complete control over
     the direction, handling and resolution of any and all claims including but
     not limited to the selection of Counsel; provided that no such claim shall
     be settled by indemnifying party without the prior approval of the
     indemnified party, such approval not to be unreasonably withheld or delayed
     after a written request for the same.  It is agreed that no settlement
     shall be made without the written consent of the indemnifying party and any
     settlement made without such consent shall not be entitled to
     indemnification by the indemnifying party, which consent will not be
     unreasonably withheld or delayed.

          (d)  This Clause shall survive termination of this Agreement.

13.  THE P.F. LABS NAME EMBLEM OR SYMBOL

     The Company shall not use or make reference to or authorize others to use
or make reference to the P.F. Labs name or any P.F. Labs emblem or symbol in
relation to the Products or in any other manner whatsoever except as shall have
been previously authorized in writing by P.F. Labs, unless required by law or
regulation.

14.  CONFIDENTIALITY

          (a)  Subject to the following provisions of this clause neither party
     shall (whether during the term of this Agreement or for a period of [****]
     thereafter) without


                                        8
<PAGE>

     the prior written consent of the other disclose to any person firm or
     company any information supplied by the other under or in contemplation of
     this Agreement or use any such information except as contemplated or
     provided hereunder.

          (b)  Each party shall inform any of its employees to whom any of the
     said information is disclosed of the provision of this clause and shall
     ensure that each such employee shall observe such provisions.

          (c)  The obligation of each party under this clause shall not apply to
     any information which

               (i)  is known to the recipient at the time of disclosure, or is
          in or subsequently enter the public domain, or which is subsequently
          disclosed to the recipient by a third party which has a lawful right
          to make such disclosure, or is required by law to be disclosed in
          which case P.F. Labs shall give prompt notice to Company prior to
          disclosure.

15.  INTELLECTUAL PROPERTY RIGHTS

     As between P.F. Labs and the Company, P.F. Labs acknowledges that the
Company and/or its Affiliates is the owner of all the know-how and other
Intellectual Property Rights disclosed to PF Labs in relation to the Product and
of the goodwill attaching to the Product and that P.F. Labs only right in
respect of the same is to use them for the purposes and during the subsistence
of this Agreement in accordance with its terms.  If P.F. Labs shall make, or
acquire rights in any improvement in the process for the manufacture of the
Product which utilizes Company information subject to Clause 14, it shall
promptly notify the Company and grant the Company a world wide non-exclusive
royalty free license to such improvement.

16.  FORCE MAJEURE

          (a)  Neither party should be under any liability whatsoever to the
     other for failure or delay in the performance of its obligations under this
     Agreement where such performance becomes impracticable by reasons of Force
     Majeure.


                                        9
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

          (b)  The party whose performance is not so affected by reason of Force
     Majeure shall be entitled to terminate this Agreement forthwith by giving
     written notice to the other party if the performance by the other party of
     its obligations under this Agreement becomes or remains impracticable by
     reason of Force Majeure for a period in excess of [****].

          (c)  In this clause the expression "Force Majeure" means war, labor
     disputes, accidents shortages of materials, acts of government (or other
     competent authorities) or any other matters (whether or not of the same
     nature as the foregoing) which are beyond the reasonable control of the
     party affected.

17.  TERMINATION PROVISIONS

          (a)  Either party may forthwith upon giving written notice terminate
     this Agreement in any of the following events:

               (i)   If the other party should be in breach of any of the terms,
          conditions or provisions of this Agreement and such breach (if capable
          of remedy) shall continue 30 days after notice in writing specifying
          the breach and requiring the same to be remedied has been given.

               (ii)  If a resolution is passed or adopted for the winding up of
          the other party (otherwise than for the purposes of and followed by an
          amalgamation or reconstruction previously approved in writing) or if a
          petition is presented for the appointment of an administrator or
          liquidation (and is not discharged within 14 days) or if a receiver or
          administrative receiver is appointed or an encumbrancer takes
          possession of the whole or any part of its undertaking or assets or it
          the other party becomes insolvent or if any analogous event shall
          occur in any territory to whose jurisdiction the other party is
          subject.

               (iii) If the other party makes or seeks to make any composition
          or arrangement with its creditors or proposes any voluntary
          arrangement or is unable


                                       10
<PAGE>

          to pay its debts as they fall due or if any distress or execution is
          levied on any of its assets (and is not discharged within 14 days) or
          if any judgment for a monetary sum be given against it and is not paid
          out with 14 days or if any analogous event shall occur is any
          territory to whose jurisdiction the other party is subject.

               (iv) If the other party ceases or threatens to cease to carry on
          the whole or any relevant part of its business or trade.

               (v)  If the other party not being a body corporate becomes
          insolvent or commits any act of bankruptcy or if any petition or
          receiving order in bankruptcy is presented or made or if any analogous
          event shall occur in any territory to whose jurisdiction the other
          party is subject.

          (b)  Termination for whatever cause of this Agreement shall be without
     prejudice to the rights of either party arising hereunder or as a result of
     any default or breach of obligation hereunder which shall have occurred
     prior to the date of such termination.

          (c)  Upon termination of this Agreement the Company shall pay to P.F.
     Labs all charges and expenses (if any) incurred by P.F. Labs prior to such
     termination in respect of any products ordered by Company which have been
     manufactured or are in the process of being manufactured by P.F. Labs, or
     in respect of any packaging materials P.F. Labs purchased for the purpose
     of supplying the quantities of Products identified in the Company's written
     estimate in respect of which P.F. Labs has not at the time of termination
     been reimbursed.

          (d)  Notwithstanding termination of this Agreement the provisions of
     Clauses 11, 12, 14 and 19(a) shall continue in full force and effect.

18.  ASSIGNMENT

          (a)  Neither party may assign any of its rights or obligations
     hereunder to any of its Affiliates without the consent of the other,
     provided either party may assign without prior written consent in case of a
     merger or acquisition or transfer of all or substantially all of a party's
     interest in the portion of its business to which this Agreement is
     applicable.


                                       11
<PAGE>

          (b)  This Agreement shall be binding on the permitted assignees and
     successors of the parties hereto.

19.  APPLICABLE LAW LANGUAGE AND SERVICE OF PROCESS

          (a)  The construction interpretation meaning validity and performance
     of this Agreement shall be governed by the laws of New Jersey which is
     agreed to be the proper law of this Agreement.

          (b)  The definitive text of this Agreement is in the English language.
     In the event of any dispute concerned the construction, interpretation or
     meaning of this Agreement reference shall be made to the Agreement written
     in English and not to any translation into any other language.

          (c)  The addresses of the parties for service of any process or
     documents required to be served by reason of law (or any rule code or
     regulation having the force of law) in the United States are as follows:

               (i)  In the case of P.F. Labs, the address first set out in this
          Agreement is:  Attn:  Mr. James Sullivan, P.F. Laboratories, 700 Union
          Blvd., Totowa, New Jersey 07512.

               (ii) In the case of the Company, the address is:  Attn:  Dr.
          Edward M. Rudnic Pharmavene, Inc. 1550 East Gude Drive, Rockville,
          Maryland 20850.

          (d)  The parties hereto submit to the non-exclusive jurisdictions of
     the States of Delaware and New Jersey of the United States of America.

20.  ADVERSE INFORMATION

     Each party agrees to notify the other immediately by telephone (with
written follow-up) in the event it learns of any inquiry, contact or
communication received from any government regulatory agency or other official
body which adversely impacts upon regulatory approval of the Products or any of
its components or ingredients, and will, to the extent readily available,
promptly furnish the other party with copies of all written reports, comments
and communications relating thereto as well as copies of all communications
directed to a regulatory agency which


                                       12
<PAGE>

concern the Products, its components or ingredients.  In addition, each party
will promptly notify the other in writing, of any information which it may
obtain or learn of concerning possible adverse experiences with a Product, its
components or ingredients, including those related to safety, indications or
efficacy.

21.  NOTICE

     Any notice request or other communication given under this Agreement shall
be in writing and may be hand-delivered or sent by pre-paid certified mail (with
return receipt requested) or sent by telecopy to the recipient at the address
first set out in this Agreement (or such other address as either party may
specify by prior written notice to the other for this purpose).

22.  ENTIRE AGREEMENT AND AMENDMENTS

          (a)  This Agreement (together with any documents referred to herein)
     supersedes any preliminary or previous correspondence, negotiations,
     arrangements, or agreements between the parties in relation to the matters
     specifically dealt with herein and represents the entire understanding of
     the parties in relation to the matters specifically dealt with herein.

          (b)  No amendment to or alteration of this Agreement shall be
     effective unless made in writing agreed and signed on behalf of each of the
     parties hereto.

23.  WAIVER

          (a)  No relaxation, forbearance, delay, or indulgence by either party
     in exercising its rights under this Agreement or any granting of time by
     such party shall prejudice or affect its rights hereunder.

          (b)  No waiver of any default or breach under this Agreement or
     failure to enforce any rights by either party shall constitute a waiver or
     any subsequent or continuing default or breach.

          (c)  No waiver shall be effective unless made in writing agreed and
     signed on behalf of the party so granting the waiver.


                                       13
<PAGE>

24.  HEADINGS

     The headings in this Agreement are solely for convenience and reference and
shall not be taken into account.

25.  SCHEDULES, ETC.

     The schedules hereto and recitals hereof shall form an integral part of
this Agreement.

26.  EXPENSES

     Each party shall pay its own costs and expenses incidental to or incurred
in relation to or in connection with the preparation, negotiation, execution,
and carrying into effect of this Agreement.

27.  RELATIONSHIP

     Each party shall be responsible for its own obligation arising under or
consequent upon this Agreement, no activities of the parties shall result in the
creation of a partnership or other relationship whereby either party shall be
held in any way responsible for the acts of omissions of the other.

28.  INVALIDITY AND SEVERABILITY

     If a provision, clause, or application of this Agreement shall be held
unlawful, invalid, or unenforceable, in whole or in part, by any court or other
competent authority, such provision, clause, or application shall be deemed
severable and this Agreement shall continue to be valid as to all other
provisions, clauses, or applications and the parties shall meet and negotiate in
good faith a valid and enforceable replacement for the severed provision,
clause, or application, which replacement shall be designed to achieve as nearly
as possible the same commercial objective as the original.


                                       14
<PAGE>

     This Agreement has been duly executed on the date(s) indicated below

PHARMAVENE, INC.                        THE P.F. LABORATORIES, INC.

By:   /S/ JAMES D. ISBISTER             By:   /S/ JAMES M. SULLIVAN
     -----------------------                 -------------------------------

Name:   James D. Isbister               Name:   James M. Sullivan
       ---------------------                   -----------------------------

Title:   President & CEO                Title:   Vice President of Logistics
       ---------------------                   -----------------------------

Date:   June 5, 1996                    Date:   May 28, 1996
       ---------------------                   -----------------------------


                                       15
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

                                   SCHEDULE 1
[****]


                                       16
<PAGE>

The information marked by [****] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

                                   SCHEDULE 2

[****]


                                       17

<PAGE>

Portions of this Exhibit have been omitted pursuant to a request for
confidential treatment.  The omitted portions, marked by [****], have been
separately filed with the Commission.

                                    AGREEMENT


     THIS AGREEMENT, dated as of July 1, 1996 (the "Agreement"), is entered into
between PHARMAVENE, INC., a Delaware corporation ("Pharmavene"), having its
principal place of business at 1550 East Gude Drive, Rockville, MD 20850, and
Athena Neurosciences, Inc., a wholly owned subsidiary of Elan Corporation plc
("Athena"), having its principal place of business at 800 Gateway Boulevard,
South San Francisco, CA 94080.

                                    RECITALS

     A.  Pharmavene is the owner or exclusive licensee of certain Patent Rights
and Trademark Rights (each as defined in Exhibit A attached) and Know-How
relating to extended release dosage forms of carbamazepine based on such Patent
Rights and/or Know-How (hereinafter defined as "Product"), a compound which may
have utility in the treatment of human diseases, including epilepsy.  "Know-How"
shall mean all data, formulas, process information or other information relating
to extended release dosage forms of carbamazepine owned by Pharmavene on the
date of this Agreement or to which Pharmavene has a transferable right on such
date. Pharmavene intends to pursue approval for marketing of Product by the U.S.
Food and Drug Administration ("FDA"), under Section 505(b)(2) New Drug
Application ("NDA") for Product.

     B.  Athena, an Affiliate of Elan Corporation plc, is a pharmaceutical
company with expertise in biopharmaceutics, and wishes to obtain for itself and
its Affiliates, as hereinafter defined, the exclusive manufacturing, marketing,
sales and distribution rights to Product worldwide (the "Territory"). 

<PAGE>

     C.  Athena and Pharmavene each desire to enter into this exclusive
arrangement for the commercial manufacture, marketing and distribution of
Product upon the terms and conditions set out below.

     D.   The foregoing recitals are hereby included in and made a part of the
Agreement which follows.

                                    AGREEMENT

     NOW, THEREFORE, in consideration of the foregoing and the mutual covenants
set forth below, the parties hereby agree as follows:

     1.   REGULATORY APPROVAL.  (a) Pursuant to the development plan and budget
approved by the Committee (defined below), Pharmavene shall use its commercially
reasonable efforts to continue the development and seek and pursue FDA approval
of Product as soon as is reasonably possible.  Pharmavene will provide such
information to Athena, at the Committee and Project Review Meetings (each as
defined below), as it may reasonably require in order to plan, monitor and
approve such further development and the strategy for obtaining regulatory
approval.  In addition, Pharmavene shall provide Athena with reasonable access
to Pharmavene's records with respect to Product at reasonable times and on
reasonable notice. 

     (b)  Upon the earlier of Approval (as hereinafter defined) of Product by
the FDA or the date on which Athena assumes full and direct responsibility for
the supply of Product, but in no event later than the expiration of the
Contracts (as hereinafter defined in Section 4) Pharmavene will transfer to
Athena the NDA.  Until that transfer occurs, Pharmavene, and thereafter, Athena,
will be responsible for compliance with all statutory and regulatory obligations
applicable to the holder of an NDA.



                                        2
<PAGE>

The information marked by [***] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

     2.   PHARMAVENE FUTURE DEVELOPMENT COST RECOVERY:  

     (a)  From the date of this Agreement, Athena shall provide (either alone,
or with partners or other collaborators) all further funding necessary to carry
out the development efforts approved by the Committee, as defined below,
including work (if any) to be performed at Pharmavene.  Athena hereby approves
in advance an amount not to exceed [****] to cover the agreed upon cost of
funding Pharmavene's development efforts for the first four (4) months of this
Agreement.

     (b)  STEERING COMMITTEE.  The progress of the U.S. regulatory approval of
Product shall be monitored by a steering committee (the "Committee") as follows:

          (i)  The Committee shall consist of four (4) individuals, two of whom
shall be appointed (and replaced, as necessary) by each party.  Meetings of the
Committee shall be held periodically at a mutually acceptable location.  The
Committee shall dissolve upon the final Approval by the FDA of Product for
marketing in the United States or at such later date as agreed upon by the
parties.  Athena shall pay the reasonable out-of-pocket expenses of all
Committee members in attending Committee meetings.  Before each meeting of the
Committee, each party shall provide to the Committee a confidential written
report summarizing its best current estimates of its expenditures and work
performed in connection with the collaboration during the period.  The Committee
shall exercise reasonable business judgment in the pursuit of its activities,
and may take action only upon the affirmative vote of at least three of its
members. The duties of the Committee shall include approving and amending, as
needed, a development plan and budget for obtaining FDA approval of Product (the
"Plan").  The Plan shall include scientific, regulatory and business milestones,
an internal and external budget and other resources to be devoted to the


                                        3
<PAGE>

approval effort.  At least thirty (30) days in advance of the end of the initial
budget period set forth in Section 2(a) budgets shall be approved for six (6)
month periods and updated quarterly.  In the event of a disagreement the matter
shall be referred to the President of each party for resolution.

     (c)  Funding for work (if any) performed at Pharmavene after the date of
this Agreement shall include all direct costs and a reasonable allocation of
Pharmavene's overhead. Pharmavene will allocate overhead to all projects in a
percentage equal to a particular project's labor divided by the total labor of
all projects multiplied by the total for all laboratory overhead and general and
administrative expenses.   Any such charges will be billed monthly and will be
payable within thirty (30) days of receipt of Pharmavene's invoice by Athena. 
Prior to and following FDA approval, Athena shall also use its commercially
reasonable efforts to develop and seek regulatory approvals to enable Product to
be commercialized in countries in the Territory outside the United States, as
provided in Section 8 below.

     (d)  The Committee will not be required to review or approve issues of
manufacturing process optimization or other development issues, except to the
extent the Approval of the NDA would be affected; provided however, the parties
will establish a rolling six (6) month budget with respect to such work (if any)
to be performed by Pharmavene and funded by Athena.

     3.   GRANTS.

     (a)  Subject to Section 4, Pharmavene hereby grants to Athena and Athena
hereby accepts from Pharmavene a sole and exclusive royalty-bearing right and
license under Patent Rights, and related Know-How to make, have made, use and
sell or have sold on its behalf Product in the Territory, including the right to
sublicense third parties (except in the United States), with the approval of
Pharmavene, which approval shall not be unreasonably withheld. 


                                        4
<PAGE>

Athena shall have the right to extend such license to its Affiliates who shall
be bound by the terms and conditions of this Agreement.  The term "Affiliate" as
applied to Athena shall mean any company or other legal entity other than
Athena, in whatever country organized, controlling or controlled by Athena or
under common control with Athena.  The term "control" means possession of the
power to direct or cause the direction of the management and policies whether
through the ownership of voting securities, by contract or otherwise. 
Affiliates shall not be deemed sublicensees and Athena shall guarantee the
performance of its Affiliates hereunder.  

     (b)  Athena agrees to forward to Pharmavene a copy of any and all fully
executed sublicense agreements for Product.  In the event of a sublicense, the
sublicensee shall be bound by all applicable terms and conditions of this
Agreement and Athena shall use reasonable efforts to enforce all such
obligations, including payments and reports due from such sublicensee.  

     (c)  If either party's tests, experiments and evaluation under this
Agreement result in an invention, discovery, improvement or other technology
necessary or useful to make, use or sell Product, whether patentable or not, and
including without limitation additional formulations or dosage strengths of
Product (an "Improvement"), ownership of such Improvement shall be determined
according to applicable patent law.  If Pharmavene owns any rights in an
Improvement, it shall license its interest to Athena as additional Patent Rights
or Know-How, without additional cost or royalty beyond that provided herein. 
This provision shall survive termination of this Agreement.  Each party shall
promptly disclose to the other all Improvements.

     (d)  Athena shall have ninety (90) days from the date of this Agreement, in
its sole discretion, to determine whether it wishes to use the Trademark Rights
in its launch of the Product, in which case Pharmavene shall license such
Trademark Rights to Athena and Athena shall use such Trademark Rights with
Product.  Such license shall be perpetual, exclusive, and 


                                        5
<PAGE>

paid-up. In the event Athena elects not to use the Trademark Rights, such rights
shall remain with Pharmavene and shall not be licensed hereunder.

     4.   MANUFACTURING.  Upon Approval of the Product, Pharmavene shall, for
the duration of its current agreements with its suppliers (the "Contracts")
provide or arrange for the supply of Athena's requirements for Product in the
Territory.  After the contracts expire or are terminated Athena will manufacture
or arrange for the manufacture of Product.  The price Athena shall pay for
Product under the Contracts shall be the prices set forth in the Contracts
(including, but not limited to contracts for raw materials, processing,
encapsulation and packaging) and Pharmavene's direct manufacturing costs (if
any) and a reasonable allocation of Pharmavene's overhead as described in
Paragraph 2(c).  At Athena's cost, approved in advance under Section 2(d) above,
(with such approval not to be unreasonably withheld) Pharmavene will continue to
provide quality assurance/quality control under the Contracts.  Any such charges
described herein will be billed monthly and will be payable within thirty (30)
days of receipt of Pharmavene's invoice by Athena.  Thereafter (or earlier, if
termination of one or more of the Contracts can be accomplished by Athena, in
its sole discretion, but with no out-of-pocket cost to Pharmavene), Athena shall
have the exclusive right and obligation to manufacture or cause to be
manufactured the Product in one or more cGMP facilities, in compliance with the
approved NDA and all applicable laws and regulations, including, without
limitation, then current FDA regulations as are in effect from time to time. 
Athena also shall have the right, at any time, subject to compliance with
applicable laws and regulations and subject to termination, assumption or
renegotiation of any of the Contracts, to have the manufacture of Product
transferred to one or more facilities of Athena and Pharmavene shall provide
reasonable cooperation, subject to Athena paying Pharmavene's reasonable out-of-
pocket expenses actually incurred at Athena's request.


                                        6
<PAGE>

The information marked by [***] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

     5.   MARKETING AND DISTRIBUTION.  Subject to Section 8, Athena shall use
its commercially reasonable efforts to market, sell and distribute, or cause to
be marketed, sold and distributed Product in each country of the Territory in
which regulatory approval is obtained.   All marketing, sale and distribution of
Product in any country shall comply with applicable laws, rules and regulations,
including but not limited to those pertaining to the packaging, labeling and
distribution of pharmaceutical products which are applicable to Product.  

     6.   COMPENSATION.  As compensation to Pharmavene under this Agreement, the
following payments shall be made:

          (a)  Within ten (10) days of the execution of this Agreement, Athena
shall pay to Pharmavene Two Million Dollars ($2,000,000) which payment shall
neither be refundable nor creditable.

          (b)  For the purposes of this Agreement, "Approval" shall mean both
(i) the final approval of the NDA by the FDA for immediate marketing of the
Product in the U.S., and (ii) the absence of any finding, ruling, order,
injunction or judgment granting  exclusivity for Tegretol XR pursuant to the
regulations of FDA, or actual or threatened proceeding or claim seeking the
same.  Within [***] of the Approval of the NDA for Product, Athena shall pay
Pharmavene the following amounts unless an action or proceeding is pending or
threatened against the FDA for its denial of exclusivity for Tegretol XR or
against Athena or Pharmavene asserting the exclusivity of Tegretol XR; provided
however, in that event the milestone payment will be due within fourteen (14)
days of the entry of a final, nonappealable court order affirming FDA's denial
of exclusivity for Tegretol XR:
          [****]


                                        7
<PAGE>

The information marked by [***] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

[****] of any such payment shall be creditable against all royalties payable
under this Agreement including royalties paid to Pharmavene on Net Revenues
received by Athena from Sublicensees as follows: Following the third full
calendar year after first commercial sale of a Product, a maximum of [****] per
year, including carryover from a prior year, may be credited against such
royalties payable in each of the next five (5) calendar years, with any carry-
forward remaining to be deducted from royalties payable in the sixth calendar
year or calendar years thereafter until the full Remaining Payment has been
credited.

          (c)  Athena shall pay to Pharmavene a royalty on the Net Sales of
Products and on the Net Sales of any other oral, coated bead/pellet, twice daily
extended release dosage form of carbamazapine hereafter acquired or developed by
Athena or any Affiliate of Athena ("Other Products") which are sold by Athena
and its Affiliates as follows:  During the first [****] following first
commercial sale, the royalty shall be [****]. During each twelve-month period
thereafter the royalty shall be [****] of Net Sales.  In addition, Athena shall
pay to Pharmavene a royalty of [****] Net Revenues received from sublicenses.  
Notwithstanding termination of this Agreement in a country(ies), royalties on
Net Sales of Product [****] shall be paid at the operative rate for Net Sales of
Product in each country of the world for so long as this Agreement remains in
effect in any country of the world.  Neither Affiliates nor distributors shall
be deemed sublicensees under this Agreement.  "Net Revenues" shall mean all
sublicense fees and milestone, royalty or other payments (other than amounts
representing the fair market value of any equity investments, or research or
development funding) actually received by Athena from any third party to
commercially market Products [****] in any country.  [****]


                                        8
<PAGE>

     All such payments shall be accompanied by a written report in reasonable 
detail, showing the calculation by which the payment amounts were determined. 
"Net Sales" shall mean all amounts actually received from the sale of Product 
or Other Products by Athena or its Affiliates, whether marketed as CARBATROL 
- -TM- or under another trademark or trade name, less actual credits, 
discounts, rebates and allowances allowed and taken, freight and insurance 
costs incurred in transporting the Product; and sales, use, excise, value 
added and similar taxes (but not including income, gross receipts or similar 
taxes), customs duties, tariffs and any other governmental charges incurred; 
provided, however, that a sale or transfer to any Affiliate for resale shall 
not be considered a sale for purposes of this provision, but the resale by 
such Affiliate shall be a sale for these purposes.

          (d)  In each year the amount of royalty due shall be calculated
quarterly as of March 31, June 30, September 30 and December 31 (each as being
the last day of an "Accounting Period") and shall be paid quarterly within the
sixty (60) days next following such date, every such payment shall be supported
by a written accounting and shall be made in United States currency.  Whenever
for the purpose of calculating royalties conversion from any foreign currency
shall be required, such conversion shall be at the rate of exchange thereafter
published in the Wall Street Journal for the last business day of the applicable
Accounting Period.

          (e)  If the transfer of or the conversion into the United States
Dollar equivalent of any remittance due hereunder is not lawful or possible in
any country, such remittance shall be made by the deposit thereof in the
currency of the country to the credit and account of Pharmavene or its nominee
in any commercial bank or trust company located in that country, prompt notice
of which shall be given to Pharmavene.  Pharmavene shall be advised in writing
in advance by Athena and provide to Athena a nominee, if so desired.


                                        9
<PAGE>

          (f)  Any tax required to be withheld by Athena under the laws of any
foreign country for the account of Pharmavene shall be promptly paid by Athena
for and on behalf of Pharmavene to the appropriate governmental authority, and
Athena shall furnish Pharmavene with proof of payment of such tax.  Any such tax
actually paid on Pharmavene's behalf shall be deducted from royalty payments due
Pharmavene. 

          (g)  Only one royalty shall be due and payable  for the manufacture,
use and sale of a Product irrespective of the number of patents or claims
thereof which cover the manufacture, use and sale of such Product.

          (h)  Athena or its designated Affiliate shall have the right to
purchase the lesser of (i) ten percent (10%) of the common stock of Pharmavene
offered in Pharmavene's Initial Public Offering ("IPO") or (ii) three million
dollars ($3,000,000) of such stock at the IPO price.

     7.   PROJECT REVIEW MEETINGS:  (a)  The progress of the development and
regulatory approval of Product, after Approval of the NDA, shall be monitored by
the parties through regular meetings between them ("Project Review Meetings"). 
Such meetings will take place semi-annually or at such other times as may be
mutually agreed upon.  The purposes of the Project Review Meetings are for the
parties to exchange information and review Athena's marketing efforts.  The
Project Review Meetings shall continue for one year after Approval of Product
to, among other things, facilitate communication between the parties.

          (b)  Following one year after Approval of Product in the United
States, Athena shall provide Pharmavene with detailed semi-annual reports of its
development, manufacturing, marketing and distribution activities under this
Agreement, including, but not limited to, plans in those countries where it is
not yet marketing Product.  Athena shall also provide such other 


                                       10
<PAGE>

The information marked by [***] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

written and oral summary reports as Pharmavene shall reasonably request and
shall meet with Pharmavene, if requested, to review and discuss these reports.

     8.   DUE DILIGENCE.  Athena shall use its commercially reasonable efforts
to have approved, manufacture, market, distribute and sell Product in the
Territory. 
 
     [****]

     (b)  The grant-back of rights to Pharmavene hereunder will include transfer
of the registration (NDA equivalent), any associated clinical data and any Know-
How originally transferred to Athena by Pharmavene.  Improvements made by Athena
on any Product will not be granted back to Pharmavene. 

     (c)   Subject to Section 9(b) below, in the event Athena fails to meet its
obligations hereunder in a country with reasonable commercial potential outside
of the Major Markets or the other European Union countries, or notifies
Pharmavene that it does not intend to market in any such country, Pharmavene
shall have the option to terminate the licenses and rights in this Agreement to
the extent applicable to such country; provided that prior to exercising this
option Pharmavene will notify Athena and provide Athena with a reasonable
opportunity to discuss the matter with Pharmavene.  Pharmavene shall be notified
promptly if Athena does not intend to market in any such country.  In the event
of termination all rights and licenses shall revert to Pharmavene, in the
Territory or in a country, as the case may be, including any NDA-equivalent
registrations for Product.

     9.   TERM AND TERMINATION; DEFAULT.  [****] Thereafter, Athena shall have a
fully paid up, perpetual, non-exclusive license in such country.



                                       11
<PAGE>

The information marked by [***] has been omitted pursuant to a request for
confidential treament.  The omitted portion has been separately filed with the
Commission.

          (a)  Athena may terminate this Agreement for any country in all or any
part of the Territory at any time (except the United States where Athena may
only terminate under this paragraph on or after [****] in its sole discretion,
upon ninety (90) days' prior written notice to Pharmavene.  Such termination
shall not affect any rights or obligations accrued as of the date of such
termination, or any other country in the Territory.  In the event of termination
by Athena under this subparagraph, all rights and licenses, and the license and
right to manufacture, market, sell and distribute Product in that country only
shall revert to and be owned exclusively by Pharmavene and Pharmavene shall be
licensed all as set forth in Section 8, except that Athena shall be entitled to
market and distribute any inventory then on hand or committed for manufacture;
and shall make any payments based on Net Sales and Net Revenue as calculated
above.  In addition, if it has undertaken sole manufacture as of the date of
such termination, Athena will use commercially reasonable efforts to continue to
supply Product to Pharmavene for a transition period of up to [****] months at
Athena's fully allocated cost for Product, including a reasonable allocation of
overhead.  Pharmavene will use its commercially reasonable efforts to establish
an alternate source of supply as soon as possible.

          (b)  Except as specifically provided in Section 8 above, with respect
to due diligence, either party may terminate this Agreement upon the breach of
any material provision of this Agreement by the other, if the defaulting party
has not cured such breach within ninety (90) days after written notice thereof
by the non-defaulting party.  In the event of termination by Pharmavene under
this subparagraph, Athena shall be entitled to market and distribute any
inventory then on hand or committed for manufacture; and shall make any payments
based on Net Sales or Net Revenues as calculated above.  


                                       12
<PAGE>

     10.  CONTROL OF PATENTS AND TRADEMARKS.  During the term of this Agreement,
Pharmavene shall have responsibility for and shall control and use commercially
reasonable efforts to pursue, and Athena shall be responsible for payment of
reasonable expenses of, the preparation, filing, prosecution and maintenance of
all its patents, trademarks and related rights pertaining to Product Patent
Rights, and shall consult with and consider the reasonable requests of Athena in
connection therewith.  With respect to any Patent Rights, each patent
application (including continuations, continuations-in-part, and divisionals),
office action, response to office action, request for terminal disclaimer, and
request for reissue or reexamination of any patent issuing from such application
shall be provided to Athena sufficiently prior to the filing of such
application, response or request to allow for review and comment by Athena. 
Pharmavene shall have the right to take any action that in its judgment is
necessary to preserve such Patent Rights.

     (a)  If Athena does not elect to use the trademark CARBATROL -TM- with 
Product as set forth in Section 3(d), Athena will adopt a new trademark for 
Product  and such trademark will belong exclusively to Athena.  Pharmavene 
will have no rights under any circumstances in such trademark.  To the extent 
Athena is licensed under Trademark Rights, Athena will seek registration of 
the CARBATROL -TM- trademark used for Product in the Territory where not 
registered, and in such case shall own and control all right, title and 
interest in any such trademark.  Such ownership and control of any trademark 
owned by Athena shall survive full or partial termination of this Agreement 
for any reason, at which time neither party shall have any right, title or 
interest, express or implied, in the other's trademarks.

          (b)  If Athena or Pharmavene has actual notice of infringement or
possible infringement of the Patent Rights, the parties shall notify each other
and confer to determine in 


                                       13
<PAGE>

good faith an appropriate course of action to enforce the Patent Rights or
otherwise abate the infringement thereof.

          Athena, at its sole expense shall initially have the right to (i)
determine and take or refrain from taking appropriate action to enforce the
Patent Rights, (ii) initiate and control any litigation or other enforcement
action, and (iii) enter into, or permit, the settlement of any such litigation
or other enforcement action regarding the Patent Rights, and shall consider, in
good faith, the interests of Pharmavene in so doing; provided that no settlement
which adversely affects Patent Rights shall be entered into without Pharmavene's
consent (not to be unreasonably withheld).  Pharmavene shall have the right to
join such suit, and shall pay its own fees and costs if it chooses to do so. 
Pharmavene shall join as a necessary party in any such suit if required to do so
by applicable law.  If Pharmavene is joined as a necessary party without its
consent, Athena will pay reasonable fees and costs actually incurred by
Pharmavene upon the presentation of detailed invoices.  Athena will keep
Pharmavene reasonably apprised of the status and progress of any such
litigation.

          If Athena does not, within one hundred twenty (120) days of recept of
written request to do so from Pharmavene, abate the infringement or file suit to
enforce the Patent Rights against at least one infringing party, Pharmavene
shall have the right to take or refrain from taking the same actions in such
enforcement action regarding the Patent Rights as Athena has under the previous
paragraph and retain any recovery, and Pharmavene shall consider, in good faith,
the interests of Athena in so doing.  Pharmavene will keep Athena reasonably
apprised of the status and progress of any such litigation.  At any time after
receipt of notice of Pharmavene's intent to file any such suit under this
Section, Athena shall have the right to join in such suit and shall pay its own
fees and costs if it chooses to do so.


                                       14
<PAGE>

          Athena shall have the right to credit fifty percent (50%) of its
expenses (including reasonable attorneys' fees and costs) incurred by Athena and
its Affiliates in the filing and prosecution, defense or settlement of any suit
or other enforcement action, against any royalties or Net Revenues owing to
Pharmavene under this Agreement, until such time as Athena has taken a credit
equal to the aggregate amount of such expenses; provided that royalties due
Pharmavene hereunder may not be reduced in any Accounting Period to less than
fifty percent (50%) of royalties otherwise payable hereunder.  This paragraph
shall apply to the defense of any infringement action brought by a third party
as well as to any suit or claim initiated by Athena or Pharmavene.

          All amounts recovered upon the final judgment or settlement of any
such suit or other enforcement action by Athena regarding the Patent Rights
shall be shared as follows:  first, to Pharmavene and Athena, pro rata, for
reimbursement of expenses (including deductions of Pharmavene royalties taken by
Athena) actually incurred by each of them in accordance with this Agreement in
the infringement proceeding to which the settlement or recovery relates (to the
extent not already recovered by Athena by credits, as provided in the above
paragraph); and thereafter, shared equally by the parties.

          Pharmavene and Athena shall fully cooperate with each other in the
planning, filing and prosecution of any suit or other enforcement action
hereunder and shall execute all such documents as may be reasonably requested by
the other.

     11.  CONFIDENTIAL INFORMATION.  Except as otherwise provided in this
Section, each party shall maintain in confidence all information of the other
party (including samples) disclosed by the other party under this Agreement (the
"Confidential Information"), and shall not use, disclose or grant the use of the
Confidential Information of the other party, except on a need-to-know basis 


                                       15
<PAGE>

to its and its Affiliates' directors, officers, employees, permitted assignees,
agents, consultants and contractors, to the extent such disclosure is reasonably
necessary in connection with such party's activities as expressly authorized by
the Agreement.  To the extent that disclosure is authorized by the Agreement,
prior to disclosure, each party hereto shall obtain agreement of any such person
or entity to hold in confidence and not make use of the Confidential Information
for any purpose other than those permitted by the Agreement.  Each party shall
notify the other  promptly of any unauthorized use or disclosure of the other
party's Confidential Information.  The obligations of this Section shall survive
any expiration or termination of this Agreement.

          (a)  The confidentiality obligations contained above shall not apply
to the extent that (i) the receiving party (the "Recipient") is required to
disclose Confidential Information by law, order or regulation of a governmental
agency or a court of competent jurisdiction, provided that the Recipient shall
provide to the disclosing party written notice and sufficient opportunity to
object to such disclosure or to request confidential treatment thereof; or (ii)
the Recipient can demonstrate that (x) the Confidential Information was public
knowledge at the time of such disclosure by the Recipient, or thereafter became
public knowledge, other than as a result of actions of the Recipient, its
affiliates or licensees in violation hereof; (y) the Confidential Information
was rightfully known to or independently developed by the Recipient, its
affiliates or licensees (as shown by its written records) prior to the date of
disclosure to the Recipient by the other party hereunder; or (z) the
Confidential Information was received by the Recipient, its affiliates or
licensees on an unrestricted basis from a source unrelated to any party to the
Agreement and not under a duty of confidentiality to the other party. 
Notwithstanding any other provision of this Agreement, during its term Athena or
Pharmavene may disclose Confidential Information of the other necessary or
useful to carry out and perform its obligations hereunder to 


                                       16
<PAGE>

any person or entity with whom Athena or Pharmavene, as the case may be, has
entered or will enter into a confidentiality agreement solely for that purpose.

     12.  TERMS OF THE AGREEMENT AND USE OF NAME.  Except as set forth in
Section 11 above, Pharmavene and Athena shall not disclose any terms or
conditions of the Agreement to any third party without the prior consent of the
other party (including without limitation press releases) with consent not to be
unreasonably withheld, unless required by law; provided that such disclosure may
be made with advance notice but without consent in connection with a public or
private financing.  

     13.  REPRESENTATIONS, WARRANTIES AND COVENANTS. 

          (a)  Pharmavene represents and warrants that it has the full right and
authority, and has taken all necessary corporate action, to enter into and
perform this Agreement, and that doing so will not conflict with or create a
default under any agreement or obligation binding on Pharmavene or any of the
assets or property which are the subject of this Agreement. Pharmavene further
warrants that it is the sole owner of the Patent Rights and the Trademark Rights
listed in the attached Exhibit A.  Exhibit A contains a complete and accurate
listing, with dates of filing and date of issuance of the Patent Rights and the
Trademark Rights, and such Patent Rights and the Trademark Rights as of the date
of this Agreement are unencumbered by any lien, charge, claim or encumbrance. 
In addition as of the date of this Agreement, Pharmavene is not aware of any
assertion by a third party that such third party's patents or trademarks will be
infringed by the manufacture, use or sale of Product which is the subject of the
NDA or the use of the Trademark but Pharmavene has not made any special
investigation in this respect.

          (b)  Athena represents and warrants that it has the full right and
authority, and has taken all necessary corporate action, to enter into and
perform this Agreement, and that doing 


                                       17
<PAGE>


so will not conflict with or create a default under any agreement or obligation
binding on Athena or any of its assets or property.

     14.  INDEMNITIES.  Athena shall indemnify and hold Pharmavene (including
its employees, officers, and directors) harmless from any third party claims,
liabilities, costs or damages caused by any manufacturing, labeling, packaging,
handling, storage, sale or distribution of Product by Athena or its Affiliates,
or by any material breach of this Agreement, or gross negligence or willful
misconduct by Athena.  Pharmavene shall indemnify and hold Athena (including its
employees, officers and directors) harmless for any third party claims,
liabilities, costs, and damages resulting from Pharmavenes development work
with respect to Product; or resulting from the manufacturing, labeling,
packaging, handling, or storage by Pharmavene or its Affiliates, or by any
material breach of this Agreement, or gross negligence or willful misconduct by
Pharmavene.  Each party agrees to notify the other promptly in writing of any
event for which it claims indemnity under this section, and to cooperate
reasonably in the defense of any such claim.  Neither party shall settle any
claim for which it claims indemnity hereunder without the prior written consent
of the other, which shall not be unreasonably withheld.

     15.  MISCELLANEOUS.

          (a)  FURTHER ASSURANCES.  Athena and Pharmavene will take all further
actions as are reasonably necessary in order to carry out the intent of this
Agreement, including without limitation entering into further documents and, in
Pharmavenes case, making available its technology, Know-How, information and
data, if necessary for such purposes.  Pharmavene will not take any action,
including without limitation the withdrawal or amendment of any NDA, or the
equivalent in any country of the Territory, which would affect the ability of
Athena hereunder to manufacture, market, sell or distribute Product.


                                       18
<PAGE>

          (b)  BOOKS AND RECORDS.  Upon the advance written request of
Pharmavene, Athena shall permit Pharmavene or its representative to have access
during normal business hours to such of the records of Athena as may be
reasonably necessary to verify the accuracy of the payment reports hereunder for
any year ending not more than three years prior to the date of such request.  If
such an inspection shows that payments are inaccurate by more than five percent
(5%), Athena shall pay the costs of such inspection.  

          (c)  NOTICES.  Any consent, notice or report required or permitted to
be given or made under the Agreement by one of the parties hereto to the other
party shall be in writing, delivered personally or by facsimile (and promptly
confirmed by personal delivery, U.S. first class mail or courier), U.S. first
class mail or courier, postage prepaid (where applicable), addressed to such
other party at its address indicated below, or to such other address as either
party may notify the other in accordance with this Section, and (unless
otherwise provided in this Agreement) shall be effective upon receipt by the
addressee.

     If to Athena:       Athena Neurosciences, Inc.
                         800 Gateway Boulevard
                         South San Francisco, California  94080
                         Attention:  General Counsel
                         Facsimile:  (415) 875-3620

     If to Pharmavene:   Pharmavene, Inc.
                         1550 East Gude Drive
                         Rockville, Maryland 20850
                         Attention: CEO
                         Facsimile: (301) 838-2501

     cc:                 Carella, Byrne, Bain, Gilfillan,
                           Cecchi, Stewart & Olstein
                         6 Becker Farm Road
                         Roseland, NJ 07068
                         Attn: Elliot M. Olstein, Esq.
                         Facsimile: (201) 597-0250


                                       19
<PAGE>

          (d)  GOVERNING LAW.  The Agreement shall be governed by and construed
in accordance  with the laws of the State of Delaware, without regard to the
conflicts of law principles thereof.  If any part of this Agreement shall be
found unenforceable by a court of competent jurisdiction, the remainder of the
Agreement shall survive in full force and effect, and the unenforceable portion
conformed to the parties' intent, to the greatest extent legally permitted.

          (e)  ASSIGNMENT.  Except as expressly provided herein, neither party
shall assign its rights or obligations under this Agreement, including to an
Affiliate, without the prior written consent of the other party hereto;
PROVIDED, HOWEVER, that either party may, without such consent, assign the
Agreement and its rights and obligations hereunder in connection with the
transfer or sale of all or substantially all of its assets or business, or in
the event of its merger or consolidation or change of control or similar
transaction.  In the event Athena desires to assign to an Affiliate, Pharmavene
will consider, in good faith, such request.

          (f)  WAIVERS AND AMENDMENTS.  No change, modification, extension,
termination or waiver of this Agreement shall be valid unless made in writing
and signed by duly authorized representatives of the parties.

          (g)  ENTIRE AGREEMENT.  Except for a Confidentiality Agreement between
the parties dated as of April 27, 1995, which remains in full force and effect
according to its terms, this Agreement, together with the exhibits hereto,
embodies the entire understanding between the parties and supersedes any prior
understanding and agreements between and among them respecting the subject
matter.  Except for that Confidentiality Agreement, there are no
representations, agreements, arrangements or understandings, oral or written,
between the parties relating to the subject matter of the Agreement which are
not fully expressed herein.


                                       20
<PAGE>

          (h)  COUNTERPARTS.  The Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

          (i)  INDEPENDENT CONTRACTOR.  Athena and Pharmavene are independent
contractors in the performance of their obligations under this Agreement, which
shall not be interpreted or construed to create a partnership, joint venture,
agency or other relationship between Pharmavene and Athena.

          (j)  ARBITRATION. All disputes arising under the Agreement shall first
be referred to the Presidents of each party, for good faith efforts at
resolution.  If such efforts are unavailing, any such dispute (other than with
respect to the validity of intellectual property) shall be finally settled by
arbitration under the Commercial Rules of the American Arbitration Association
in effect at the time, by one or more arbitrator(s) appointed in accordance with
such Rules.  The award or judgment of the arbitrator(s) shall be final, binding
and enforceable in a court of competent jurisdiction.  The prevailing party in
any arbitration or legal proceeding shall be entitled to recover its costs,
including reasonable attorneys fees, from the other party as a part of any
award or judgment.

     (k)  FORCE MAJEURE.  Neither party shall be held liable or responsible to
the other party nor be deemed to have defaulted under or breached this Agreement
for failure or delay in fulfilling or performing any term of this Agreement when
such failure or delay is caused by or results from causes beyond the reasonable
control of the affected party including but not limited to fire, floods,
earthquakes, embargoes, war, acts of war (whether war is declared or not),
insurrections, riots, civil commotions, strikes, lockouts or other labor
disturbances, acts of God or acts, omissions or 


                                       21
<PAGE>

delays in acting by any governmental authority or the other party; provided that
this provision shall not be applicable to events which extend beyond six (6)
months.

     IN WITNESS WHEREOF, the parties have duly executed and delivered the
Agreement as of the date first written above.

PHARMAVENE, INC.                        ATHENA NEUROSCIENCES,
                                             INC.



By:___________________________               By:___________________________

Name:_________________________               Name:_________________________

Title:________________________               Title:________________________

Date:_________________________               Date:_________________________


                                       22
<PAGE>

The information marked by [***] has been omitted pursuant to a request for
confidential treatment.  The omitted portion has been separately filed with the
Commission.

                                    EXHIBIT A

     PATENT RIGHTS "Patent Rights" as used herein shall mean (a) the patent
applications listed below, together with all corresponding foreign patent
applications heretofore or hereafter filed or having legal force in any country;
and (b) all patents that have issued or in the future issue from such
applications, including utility, model and design patents and certificates of
invention; and all divisionals, continuations, continuations-in-part, reissues,
renewals, supplementary protection certificates, extensions or additions to any
such patents.

U.S. Patent No. 5,326,570, issued July 5, 1994.
[****]


                                       23

<PAGE>

                              EMPLOYMENT AGREEMENT


         This EMPLOYMENT AGREEMENT, dated as of June 25, 1996 is entered into by
and between PHARMAVENE, INC., a Delaware corporation (the "Company") and Robert
S. Cohen (the "Employee").

         WHEREAS, the Company desires to employ the Employee as President and
Chief Operating Officer of the Company, and the Employee desires to accept such
employment by the Company, on the terms and subject to the conditions
hereinafter set forth.

         NOW, THEREFORE, in consideration of the mutual covenants and
obligations hereinafter set forth, the parties hereto agree as follows:

         1.   EMPLOYMENT.  The Company hereby employs the Employee, and the
Employee hereby accepts employment by the Company, upon the terms and conditions
hereinafter set forth.

         2.   TERM.  Subject to the provisions of SECTIONS 6, 7, 8, and 9 below,
the employment of the Employee hereunder will be for the three-year period
commencing July 1, 1996 (the "Commencement Date") and ending on the first
anniversary of such Commencement Date.  Unless either party gives written notice
of determination not to renew at least one hundred eighty (180) days prior to
the third anniversary of the Commencement Date, this Agreement shall be renewed
for one (1) year from that anniversary.  Thereafter, unless either party gives
written notice of determination not to renew at least one hundred eighty (180)
days prior to any succeeding anniversary of the Commencement Date, this
Agreement shall be renewed for one (1) year from each anniversary.  The term
"Employment Period" shall mean the one-year period provided for in this
SECTION 2 and any extension thereof, or any shorter period resulting from any
termination of employment under SECTION 6, 7, 8, or 9 below.

         3.   DUTIES AND RESPONSIBILITIES.  The Employee will be employed as
President and Chief Operating Officer of the Company.  The Employee will perform
such duties and services, consistent with his position, as may be assigned to
him from time to time by the Board of Directors or the Chief Executive Officer.
In furtherance of the foregoing, the Employee hereby agrees to perform well and
faithfully such duties and responsibilities and the other reasonable duties and
responsibilities assigned to him from time to time by the Board of Directors of
the Company or the Chief Executive Officer.

         4.   TIME TO BE DEVOTED TO EMPLOYMENT.  Except for reasonable
vacations, absences due to temporary illness, and activities which have been
mutually agreed to by the parties,  the Employee shall devote substantially all
of his time, attention and energies to the business of the Company during the
Employment Period.  During the Employment Period, the Employee will not be
engaged in any other business activity which, in the reasonable judgment of the
Company, conflicts with the duties of the Employee hereunder, whether or not
such activity is pursued for gain, profit or other pecuniary advantage.  It is
understood, however, that the Employee will serve as a Director of and will be
employed as a Consultant by Trophix Pharmaceuticals, Inc. ("Trophix") for up to
180 days after the Commencement Date.  It is further understood that the
employee will work no more than 8 days per month as a Consultant to Trophix and
that the Employee will be on a leave without pay status from the Company during
the time(s) he works as a consultant for Trophix Pharmaceuticals.

<PAGE>

         5.   COMPENSATION; REIMBURSEMENT.  (a)  The Company (or, at the
Company's option, any subsidiary or affiliate thereof) will pay to the Employee
an annual base salary (the "Base Salary") of not less than $200,000, payable in
such installments as is the policy of the Company with respect to employees of
the Company at substantially the same employment level as the Employee.  The
employee shall be eligible to receive an annual bonus of up to 33 1/3 of the
Employee's base salary based upon the Employee's performance.

         (b)  During the Employment Period, the Employee will be entitled to the
fringe benefits that are made available from time to time to employees of the
Company at substantially the same employment level as the Employee, including
eligibility to participate in any Company stock option or bonus plans.

         (c)  The Company will reimburse the Employee, in accordance with the
practice of the Company from time to time, for all reasonable and necessary
travel expenses and other disbursements incurred by him for or on behalf of the
Company in the performance of his duties hereunder upon presentation by the
Employee to the Company of appropriate vouchers.

         6.   INVOLUNTARY TERMINATION.  If the Employee dies, then the
Employee's employment shall be deemed to terminate on the date of the Employee's
death.  If the Employee is incapacitated or disabled by accident, sickness or
otherwise so as to render him mentally or physically incapable of performing the
services required to be performed by him under this Agreement for a period of
ninety (90) consecutive days or longer, or for ninety (90) days during any six-
month period (such condition being herein referred to as "Disability"), then the
Company, at its option, may terminate the employment of the Employee under this
Agreement immediately upon giving him notice to that effect.  In the case of a
Disability, until the Company shall have terminated the Employee's employment
hereunder in accordance with the foregoing, the Employee will be entitled to
receive compensation, at the rate and in the manner provided in SECTION 5 above,
notwithstanding any such Disability.  Termination pursuant to this SECTION 6 is
hereinafter referred to as an "Involuntary Termination".

         7.   TERMINATION FOR CAUSE.  Upon a vote of the majority of the Board
of Directors, the Company may terminate the employment of the Employee hereunder
at any time during the Employment Period for "cause" (such termination being
hereinafter referred to as a "Termination for Cause") by giving the Employee
notice of such termination, whereupon such termination shall take effect
immediately.  For the purpose of this SECTION 7, "cause" will mean (a) the
Employee's willful misconduct with respect to the business and affairs of the
Company or any subsidiary or affiliate thereof, (b) the Employee's neglect of
duties or failure to act which can reasonably be expected to affect materially
and adversely the business or affairs of the Company or any subsidiary or
affiliate thereof, (c) the Employee's material breach of any of the agreements
contained in SECTION 3 or 4 hereof, or the Employee's breach of the Proprietary
Information and Invention Agreement referred to in SECTION 11 below, (d) the
commission by the Employee of an act involving moral turpitude relating to the
Company or fraud, or (e) the Employee's conviction of any felony, or of any
misdemeanor involving fraud, theft, embezzlement, forgery or moral turpitude.

         8.   TERMINATION WITHOUT CAUSE.  The Company may terminate the
employment of the Employee hereunder at any time during the Employment Period
without "cause" (such termination being hereinafter referred to as a
"Termination Without Cause") by giving the Employee written notice of such
termination.  Upon the giving of such notice, termination of employment under
this SECTION 8 will take effect in ninety (90) days.


                                       -2-
<PAGE>

         9.   VOLUNTARY TERMINATION.  Any termination of the employment of the
Employee hereunder otherwise than as a result of an Involuntary Termination, a
Termination For Cause or a Termination Without Cause will be referred
hereinafter as a "Voluntary Termination."  Following reasonable notice, a
Voluntary Termination will be deemed to be effective upon the date specified in
such notice or, in the absence of such specification, upon the date of the
giving of such notice.

         10.  EFFECT OF TERMINATION OF EMPLOYMENT.  (a)  Upon termination of the
Employee's employment hereunder pursuant to a Voluntary Termination or a
Termination For Cause, neither the Employee nor his beneficiary or estate will
have any further rights or claims against the Company under this Agreement
except to receive:

          (i) the unpaid portion of the Base Salary provided for in SECTION 5(a)
above, computed on a PRO RATA basis to the date of such termination; and

          (ii)     reimbursement for any expenses for which the Employee shall
not have theretofore been reimbursed as provided in SECTION 5(c) above.

          (iii)    retention in the Company's 401(k) Program and other Company
employee benefits (as required by law) and the opportunity to purchase health
benefits under the Company's health benefits program, as required by COBRA.

         (b)  Upon termination of the Employee's employment hereunder pursuant
to an Involuntary Termination, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to six (6) months' Base
Salary, payable at the same rate and in the same manner as set forth in
SECTION 5 above.

         (c)  Upon termination of the Employee's employment hereunder pursuant
to a Termination Without Cause, neither the Employee nor his beneficiary or
estate will have any further rights or claims against the Company under this
Agreement except to receive a termination payment equal to that provided for in
SECTION 10(a) above, plus an aggregate amount equal to the lesser of (i) one (1)
year's Base Salary, payable in twelve (12) equal monthly installments or (ii)
the Base Salary for the then remaining term of the Employment Period, whichever
is smaller, in each case payable at the same rate and in the same manner as set
forth in SECTION 5 above.

         11.  PROPRIETARY INFORMATION AND INVENTION AGREEMENT.  The Employee has
executed the Proprietary Information and Invention Agreement, a copy of which is
attached hereto as EXHIBIT A, and covenants that he will comply with the terms
of such Proprietary Information and Invention Agreement during the term thereof.


         12.  ENFORCEMENT.  It is the desire and intent of the parties hereto
that the provisions of this Agreement will be enforced to the fullest extent
permissible under the laws and public policies applied in each jurisdiction in
which enforcement is sought.  Accordingly, to the extent that a restriction
contained in this Agreement is more restrictive than permitted by the laws of
any jurisdiction where this Agreement may be subject to review and
interpretation, the terms of such restriction, for the purpose only of the
operation of such restriction in such jurisdiction, will be the maximum
restriction allowed by the laws of such jurisdiction and such restriction will
be deemed to have been revised accordingly herein.  A court having jurisdiction
over an action arising out of or seeking enforcement of any restriction
contained in this Agreement may modify the terms of such restriction in
accordance with this SECTION 12.


                                       -3-
<PAGE>

         13.  REMEDIES; SURVIVAL.  (a)  The Employee acknowledges and
understands that the provisions of this Agreement are of a special and unique
nature, the loss of which cannot be accurately compensated for in damages by an
action at law, and that the breach or threatened breach of the provisions of
this Agreement would cause the Company irreparable harm.  In the event of a
breach or threatened breach by the Employee of the provisions of SECTION 11
above, the Company will be entitled to an injunction restraining him from such
breach.  Nothing herein contained will be construed as prohibiting the Company
from pursuing any other remedies available at law for any breach or threatened
breach of this Agreement.

         (b)  Notwithstanding anything contained in this Agreement to the
contrary, the provisions of SECTIONS 11, 12, 14, 15, 16, 17, 18, 22, 23, and
this SECTION 13, will survive the expiration or other termination of this
Agreement until, by their terms, such provisions are no longer operative.

         14.  STOCK OPTIONS.  On the Commencement Date the Employee will be
granted options to purchase 225,000 shares of Common Stock which will vest over
five (5) years (20% annually).  The options will be granted as Incentive Stock
Options (ISO) to the maximum allowed by law and regulation.  Non Qualified Stock
Options will be granted to make up any difference between the option grants
described in this Section 14 and the amount of allowable ISO grants, if any.
The exercise price of such stock options will be equal to the fair market value
of the Company's Common Stock on the date of grant (but in no event less than
85% of the price per share of Common Stock received by the Company from an
initial public offering consummated by the Company within 180 days after the
date hereof).  The options will be subject to the terms and conditions of the
Company's Stock Option Plan, which is attached hereto as Exhibit B.  The
Employee will be eligible to receive additional stock options annually based on
performance.  In the event an optionee is terminated as an employee of the
Company or a subsidiary within one (1) year of either of the events specified in
(i) or (ii) below, or the employee's responsibilities or duties are
substantially reduced within one (1) year of either of the events specified in
(i) or (ii) below, all outstanding Stock Options at that date of termination or
date of reduction of responsibilities or duties shall become immediately
exercisable for a period of three (3) months.

          (i)   as a result of or in connection with any tender offer,
                exchange offer, merger or other business combination, sale of
                assets or contested election, or combination of the
                foregoing, the persons who were Directors of the Company just
                prior to such event cease to constitute a majority of the
                Company's Board of Directors; or

          (ii)  the stockholders of the Company approve an agreement
                providing for a transaction in which the Company will cease
                to be an independent publicly-owned corporation or a sale or
                other disposition of all or substantially all of the assets
                of the Company occurs.

         15.  RELOCATION.  The Company shall reimburse the Employee for
reasonable expenses, not to exceed an aggregate of $100,000.00, associated with
household packing and moving, realtor's fees and other closing costs, as well as
temporary housing not to exceed one hundred twenty (120) days, relating to the
Employee's relocation to the Rockville, Maryland area.

         16.  NOTICES.  All notices, demands and other communications which are
required to be given, served or sent pursuant to this Agreement will be in
writing and will be delivered personally or sent by air courier or first class
certified or registered mail, return receipt requested and postage prepaid,
addressed as follows:


                                       -4-
<PAGE>

         If to the Employee:

         Robert S. Cohen
         17 Kenneth Road
         Upper Montclair, New Jersey  07043

         with a copy to:

         Ira A. Rosenberg, Esq.
         Sills Cummis Zuckerman Radin
           Tischman Epstein & Gross, P.A.
         One Riverfront Plaza
         Newark, New Jersey  07102-5400

         If to the Company:

         Pharmavene, Inc.
         1550 East Gude Drive
         Rockville, Maryland  20850

         Attention:  Secretary

All notices and other communications given to any party hereto in accordance
with the provisions of this Agreement will be deemed to have been given on the
date of delivery if personally delivered; on the business day after the date
when sent if sent by air courier; and on the third business day after the date
when sent if sent by mail, in each case addressed to such party as provided in
this SECTION 14 or in accordance with the latest unrevoked direction from such
party.

         17.  BINDING AGREEMENT; BENEFIT.  The provisions of this Agreement will
be binding upon and will inure to the benefit of, the respective heirs, legal
representatives and successors of the parties hereto.

         18.  GOVERNING LAW.  This Agreement will be governed by, and construed
and enforced in accordance with, the laws of the State of Maryland (not
including the choice of law provisions thereof).

         19.  WAIVER OF BREACH.  The waiver by either party of a breach of any
provision of this Agreement by the other party must be in writing and will not
operate or be construed as a waiver of any subsequent breach by such other
party.

         20.  ENTIRE AGREEMENT; AMENDMENTS.  This Agreement contains the entire
agreement between the parties with respect to the subject matter hereof and
supersedes all prior agreements or understanding among the parties with respect
thereto.  This Agreement may be amended only by an agreement in writing signed
by the parties hereto.

         21.  HEADINGS.  The Section headings contained in this Agreement are
for reference purposes only and will not affect in any way the meaning or
interpretation of this Agreement.

         22.  SEVERABILITY.  Subject to the provisions of SECTION 12 above, any
provision of this Agreement that is prohibited or unenforceable in any
jurisdiction will, as to such jurisdiction, be ineffective to the extent of such
prohibition or unenforceability without invalidating the remaining provisions
hereof, and any such prohibition or unenforceability in any jurisdiction will
not invalidate or render unenforceable such provision in any other jurisdiction.


                                       -5-
<PAGE>

         23.  ASSIGNMENT.  This Agreement is personal in its nature and the
parties hereto shall not, without the consent of the other, assign or transfer
this Agreement or any rights or obligations hereunder; PROVIDED, HOWEVER, that
the provisions hereof will inure to the benefit of, and be binding upon, each
successor of the Company, whether by merger, consolidation, transfer of all or
substantially all assets or otherwise.

         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the date first above written.


                          PHARMAVENE, INC.



                          By: /s/ James D. Isbister
                              -----------------------------------------------
                              James D. Isbister, Chairman, Board of Directors
                              and CEO



                              /s/ Robert S. Cohen
                              ----------------------------------------------
                              Robert S. Cohen


                                       -6-

<PAGE>
                                                                    EXHIBIT 11.1
 
                                PHARMAVENE, INC.
                        (A DEVELOPMENT STAGE ENTERPRISE)
                  COMPUTATION OF HISTORICAL NET LOSS PER SHARE
 
<TABLE>
<CAPTION>
                                                                CUMULATIVE                                 CUMULATIVE
                                                              FOR THE PERIOD                             FOR THE PERIOD
                                                             FEBRUARY 16, 1990                          FEBRUARY 16, 1990
                                                                 (DATE OF        FOR THE THREE MONTHS       (DATE OF
                          FOR THE YEARS ENDED DECEMBER 31,      INCEPTION)          ENDED MARCH 31         INCEPTION)
                         ----------------------------------         TO          ----------------------         TO
                            1993        1994        1995     DECEMBER 31, 1995     1995        1996      MARCH 31, 1996
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
<S>                      <C>         <C>         <C>         <C>                <C>         <C>         <C>
Net loss...............  $(5,482,771) $(4,144,982) $(6,679,218)    $(24,208,911) $(1,557,135) $(5,287,295)    $(29,496,206)
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
Weighted average common
 shares outstanding....     237,057     239,480     276,917         147,533        247,612     289,284         147,546
Net common shares
 issuable upon the
 exercise of
 outstanding options
 and warrants issued
 within one year of
 initial public
 offering..............   1,021,784   1,021,784   1,021,784       1,021,784      1,021,784   1,021,784       1,021,784
Net common shares
 issuable upon
 conversion of
 convertible notes
 payable to investors
 issued within one year
 of initial public
 offering..............   2,196,632   2,196,632   2,196,632       2,196,632      2,196,632   2,196,632       2,196,632
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
Weighted average common
 shares outstanding....   3,455,473   3,457,896   3,495,333       3,365,949      3,466,028   3,507,700       3,365,962
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
Net loss per common and
 common share
 equivalent............     $(1.59)     $(1.20)     $(1.91)            $(7.19)     $(0.45)     $(1.51)            $(8.76)
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
                         ----------  ----------  ----------  -----------------  ----------  ----------  -----------------
</TABLE>
 
<PAGE>
                                                       REGISTRATION NO. 33-98706
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
 
                       SECURITIES AND EXCHANGE COMMISSION
 
                             WASHINGTON, D.C. 20549
 
                            ------------------------
 
                                    EXHIBITS
                                       TO
                                AMENDMENT NO. 2
                                       TO
                                    FORM S-1
 
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933
 
                            ------------------------
 
                                PHARMAVENE, INC.
             (Exact name of Registrant as specified in its charter)
 
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------


© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission