MYLAN LABORATORIES INC
8-K, 1998-06-30
PHARMACEUTICAL PREPARATIONS
Previous: NATIONWIDE INVESTING FOUNDATION, NSAR-A, 1998-06-30
Next: NASHUA CORP, NT 11-K, 1998-06-30



<PAGE>
 
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 8-K


                                 Current Report


                     Pursuant to Section 13 or 15(d) of the
                      Securities and Exchange Act of 1934



                                  June 24, 1998
               ------------------------------------------------
                Date of Report (Date of earliest event reported)



                            MYLAN LABORATORIES INC.
                      ------------------------------------
             (Exact name of registrant as specified in its charter)


  Pennsylvania                    1-9114                     25-1211621
 ---------------                -----------                 -------------
 (State of other                (Commission                 (IRS Employer
 jurisdiction of                File Number)                  ID Number)
 incorporation)                                           


                              130 Seventh Street
                             1030 Century Building
                        Pittsburgh, Pennsylvania 15222
                    ------------------------------------------
                         (Address of principal offices)



                                 (412) 232-0100
              ----------------------------------------------------
              (Registrant's telephone number, including area code)
<PAGE>
 
5.  Other Events.


Merger Agreement
- ----------------
   
     On June 24, 1998, Mylan Laboratories Inc. (the "Company") entered into an
Agreement and Plan of Merger (the "Merger Agreement") with Penederm Incorporated
("Penederm") and Mylan's wholly owned subsidiary, MLI Acquisition Corp. ("Merger
Sub").  The Merger Agreement, attached hereto as Exhibit 2.1, provides that,
upon satisfaction of certain conditions, Merger Sub will merge into Penederm,
with Penederm surviving the merger as a wholly owned subsidiary of the Company
(the "Merger").  Pursuant to the Merger Agreement, each share of common stock of
Penederm ("Penederm Common Stock") will be exchanged for 0.68 shares of common
stock of the Company.  Also in connection with the Merger, Penederm entered into
an option agreement, attached hereto as Exhibit 99.1, whereby Penederm granted
the Company an option to purchase 1,717,878 shares of Penederm Common Stock
(approximately 19.9% of the outstanding Penederm Common Stock as of June 24,
1998) from Penederm at a price of $20.00 per share if certain triggering events
occur. In addition, each of the directors of Penederm agreed to vote in their
capacities as stockholders of Penederm in favor of the Merger and against any
competing offer. The forms of voting agreement are attached hereto as Exhibits
99.2 and 99.3.

    
     On June 24, 1998, the Company and Penederm issued a press release related
to the Merger Agreement.  The press release is attached hereto as Exhibit 99.4.

     The Exhibits hereto are incorporated by reference herein and form a
integral part hereof.

     Item 7.  Financial Statements and Exhibits.

     Exhibits.
     -------- 

     2.1   Agreement and Plan of Merger dated as of June 24, 1998, among Mylan
           Laboratories Inc., MLI Acquisition Corp. and Penederm Incorporated.

     99.1  Option Agreement, dated June 24, 1998 between Penederm Incorporated
           and Mylan Laboratories Inc.

     99.2  Form of Voting Agreement, dated June 24, 1998, between Mylan
           Laboratories Inc. and certain directors of Penederm Incorporated.

     99.3  Alternate Form of Voting Agreement, dated June 24, 1998, between
           Mylan Laboratories Inc. and a director of Penederm Incorporated.

     99.4  Press Release dated June 24, 1998.
<PAGE>
 
                                   SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized

                                MYLAN LABORATORIES INC.

Date:     June 30, 1998         /s/  Donald C. Schilling
      ----------------------    -------------------------------------
                                Donald C. Schilling
                                Vice President Finance
<PAGE>
 
                                 EXHIBIT INDEX

     Exhibit
     -------

     2.1   Agreement and Plan of Merger dated as of June 24, 1998, among Mylan
           Laboratories Inc., MLI Acquisition Corp. and Penederm Incorporated.

     99.1  Option Agreement, dated June 24, 1998 between the Company and Mylan
           Laboratories Inc.

     99.2  Form of Voting Agreement, dated June 24, 1998, between Mylan
           Laboratories Inc. and certain directors of Penederm Incorporated.

     99.3  Alternate Form of Voting Agreement, dated June 24, 1998, between
           Mylan Laboratories Inc. and a director of Penederm Incorporated.

     99.4  Press Release dated June 24, 1998.

<PAGE>

                                                                     Exhibit 2.1



 
                          AGREEMENT AND PLAN OF MERGER

                                  BY AND AMONG

                             PENEDERM INCORPORATED

                                      AND

                             MLI ACQUISITION CORP.

                                      AND

                            MYLAN LABORATORIES INC.

                                 June 24, 1998



<PAGE>
 
                               TABLE OF CONTENTS



<TABLE> 
<CAPTION> 
                                                                                                               Page
                                                                                                               ----
<S>      <C> 
1.       NAME OF SURVIVING CORPORATION, CERTIFICATE OF INCORPORATION, BYLAWS......................................2
         1.1      Name of Surviving Corporation...................................................................2
         1.2      Certificate of Incorporation....................................................................2
         1.3      Bylaws; Directors and Officers..................................................................2
         1.4      Filing of Certificate of Merger; Effective Date; Effective Time.................................3
         1.5      Effects of Merger...............................................................................3
         1.6      Tax-Free Reorganization.........................................................................3

2.       STATUS AND CONVERSION OF SECURITIES......................................................................3
         2.1      Company Capital Stock...........................................................................3
                  (a)      Conversion of Company Common Stock Into Parent Common Stock............................3
                  (b)      Delivery of Certificates...............................................................4
                  (c)      Dividends; Transfer Taxes; Withholding.................................................5
                  (d)      No Fractional Shares...................................................................6
                  (e)      Return of Exchange Fund................................................................6
                  (f)      Adjustment of Exchange Ratio...........................................................7
                  (g)      No Further Ownership Rights in Company Common Stock....................................7
                  (h)      Closing of the Company Transfer Books..................................................7
                  (i)      Further Assurances.....................................................................7
         2.2      Subsidiary Common Stock.........................................................................8
         2.3      Assumption of Stock Options; Company Warrant; Employee Stock Purchase Plan......................8
         2.4      Closing.........................................................................................9

3.       REPRESENTATIONS, WARRANTIES AND AGREEMENTS...............................................................9
         3.1      Representations, Warranties and Agreements of the Company.......................................9
                  (a)      Organization, Standing and Power......................................................10
                  (b)      Capital Structure.....................................................................10
                  (c)      Authority.............................................................................12
                  (d)      Consents and Approvals; No Violation..................................................13
                  (e)      SEC Documents and Other Reports.......................................................14
                  (f)      Registration Statement and Prospectus/Proxy Statement.................................15
                  (g)      Absence of Certain Changes or Events..................................................15
                  (h)      Permits and Compliance................................................................16
                  (i)      Tax Matters...........................................................................17
                  (j)      Actions and Proceedings...............................................................18
                  (k)      FDA and Related Matters...............................................................19
                  (l)      Certain Agreements....................................................................20
                  (m)      Material Contracts....................................................................21
                  (n)      Opinion of Financial Advisor..........................................................21
                  (o)      Takeover Provisions Inapplicable......................................................21
                  (p)      Required Vote of the Company Stockholders.............................................21
                  (q)      Finders and Investment Bankers........................................................22
                  (r)      Authorized Stock......................................................................22
</TABLE> 
                                     - i -
<PAGE>
 
<TABLE> 
<S>      <C> 
                  (s)      Company Affiliates....................................................................22
                  (t)      Owned Real Property...................................................................22
                  (u)      Leased Real Estate....................................................................22
                  (v)      Owned and Leased Tangible Personal Property...........................................23
                  (w)      Physical Condition of Property........................................................23
                  (x)      Patents and Certain Other Intellectual Property Rights................................23
                  (y)      Accounts Receivable...................................................................24
                  (z)      Insurance and Bonds...................................................................24
                  (aa)     Product Warranties and Liability......................................................24
                  (bb)     Contracts, Proposals and Bids.........................................................25
                  (cc)     Labor and Employment Matters..........................................................25
                  (dd)     Insider Contracts.....................................................................27
                  (ee)     Other Material Contracts..............................................................27
                  (ff)     Export of Products and Technologies...................................................28
                  (gg)     Absence of Illegal Payments...........................................................28
                  (hh)     Absence of Anti-Boycott Violations....................................................29
                  (ii)     Environmental Matters.................................................................29
                  (jj)     No Adverse Actions....................................................................31
         3.2      Representations, Warranties and Agreements of the Parent.......................................31
                  (a)      Organization, Standing and Power......................................................31
                  (b)      Capital Structure.....................................................................32
                  (c)      Authority.............................................................................33
                  (d)      Consents and Approvals; No Violation..................................................34
                  (e)      SEC Documents and Other Reports.......................................................35
                  (f)      Registration Statement and Prospectus/Proxy Statement.................................36
                  (g)      Absence of Certain Changes or Events..................................................36
                  (h)      Permits and Compliance................................................................36
                  (i)      Actions and Proceedings...............................................................37
                  (j)      FDA Matters...........................................................................38
                  (k)      Labor Relations.......................................................................39
                  (l)      Patents and Certain Other Intellectual Property Rights................................39
                  (m)      Parent Common Stock...................................................................39
                  (n)      Opinion of Financial Advisor..........................................................39
                  (o)      Finders and Investment Bankers........................................................40
                  (p)      Parent Affiliate Agreements...........................................................40
         3.3      Representations and Warranties as to the Merger Subsidiary.....................................40
                  (a)      Organization, Standing, Power and Capitalization of the Merger Subsidiary.............40
                  (b)      Business of the Merger Subsidiary.....................................................40
                  (c)      Authorization; Binding Agreement......................................................40
                  (d)      Compliance With Other Instruments, Etc................................................41
                  (e)      Governmental and Other Consents, Etc..................................................41

4.       COVENANTS...............................................................................................41
         4.1      Covenants of the Company.......................................................................41
                  (a)      Action in Furtherance of Merger.......................................................41
                  (b)      Maintenance of Properties.............................................................42
</TABLE> 
                                    - ii -
<PAGE>
 
<TABLE> 
<S>      <C> 
                  (c)      Access and Information................................................................42
                  (d)      Conduct of Business...................................................................43
                  (e)      Capital Stock.........................................................................44
                  (f)      No Solicitation.......................................................................45
                  (g)      No Final Put Notice...................................................................47
                  (h)      Compensation Matters..................................................................47
                  (i)      Contracts.............................................................................47
                  (j)      Tax Matters...........................................................................47
                  (k)      Amendments to the Schedules...........................................................47
                  (l)      Notification of Certain Matters.......................................................48
                  (m)      Stockholder Approval..................................................................48
                  (n)      Financial Statements..................................................................49
                  (o)      Proxy Statement.......................................................................49
                  (p)      Company Affiliates....................................................................49
                  (q)      Takeover Statutes.....................................................................49
                  (r)      Prohibited Transactions...............................................................49
                  (s)      Accounting Changes....................................................................50
                  (t)      Compliance With Law...................................................................50
                  (u)      Company Affiliates Agreements.........................................................50
         4.2      Covenants of the Parent........................................................................50
                  (a)      Action in Furtherance of Merger.......................................................50
                  (b)      Maintenance of Properties.............................................................51
                  (c)      Access and Information................................................................51
                  (d)      Listing Application...................................................................51
                  (e)      Public Filings........................................................................51
                  (f)      Registration Statement................................................................51
                  (g)      Conduct of Business...................................................................51
         4.3      Covenants as to the Merger Subsidiary..........................................................52
                  (a)      No Business...........................................................................52
                  (b)      Access................................................................................52
                  (c)      Actions in Furtherance of Merger......................................................52
         4.4      Covenants of the Company and the Parent........................................................52
                  (a)      Registration Statement................................................................52
                  (b)      Tax-Free Reorganization Treatment.....................................................52

5.       CONDITIONS TO CLOSING; ABANDONMENT AND TERMINATION......................................................53
         5.1      Conditions to Each Party's Obligation to Effect the Merger.....................................53
                  (a)      Company Stockholder Approval..........................................................53
                  (b)      Consents..............................................................................53
                  (c)      Effectiveness.........................................................................53
                  (d)      Listing...............................................................................53
                  (e)      No Legal Restraints...................................................................53
         5.2      Conditions to the Company's Closing and Its Right to Abandon...................................53
                  (a)      No Material Adverse Effect............................................................54
                  (b)      No Material Adverse Change............................................................54
                  (c)      Officer's Certificate.................................................................54
                  (d)      Tax Opinion...........................................................................54
</TABLE> 
                                    - iii -
<PAGE>
 
<TABLE> 
<S>      <C> 
                  (e)      Tax Certificate.......................................................................55
         5.3      Conditions to the Parent's and the Merger Subsidiary's Closing and Right of the Parent
                  and the Merger Subsidiary to Abandon...........................................................56
                  (a)      No Material Adverse Effect............................................................56
                  (b)      No Material Adverse Change............................................................57
                  (c)      Officer's Certificate.................................................................57
                  (d)      Tax Opinion...........................................................................57
                  (e)      Tax Certificates......................................................................58
                  (f)      Outstanding Shares of Preferred Stock.................................................58
                  (g)      FIRPTA Statement......................................................................58

6.       ADDITIONAL PROVISIONS FOR ABANDONMENT AND TERMINATION...................................................58
         6.1      Provisions of Abandonment and Termination......................................................58
                  (a)      Mutual Agreement......................................................................59
                  (b)      Violation of Order....................................................................59
                  (c)      Other Transactions Involving Company..................................................59
                  (d)      Superior Proposal.....................................................................60
         6.2      Termination of Agreement.......................................................................61
         6.3      Effect of Abandonment or Termination...........................................................61

7.       EXPENSES................................................................................................61
         7.1      Costs and Expenses.............................................................................61
                  (a)      Payment of Own Expenses...............................................................61
                  (b)      Termination Fee.......................................................................61

8.       MISCELLANEOUS...........................................................................................63
         8.1      Certification of the Company's Shareholder Votes, Etc..........................................63
         8.2      Certification of the Parent's Stockholder Votes, Etc...........................................63
         8.3      Termination of Covenants, Representations and Warranties.......................................63
         8.4      Certain Tax Matters............................................................................63
         8.5      Execution in Counterparts......................................................................67
         8.6      Waivers and Amendments.........................................................................67
         8.7      Confidentiality................................................................................67
         8.8      Indemnification; Directors and Officers Insurance..............................................67
         8.9      Notices........................................................................................68
         8.10     Entire Agreement; No Third-Party Beneficiaries; Rights of Ownership............................69
         8.11     Governing Law..................................................................................69
         8.12     Partial Invalidity.............................................................................69
         8.13     Publicity......................................................................................69
         8.14     Defined Terms..................................................................................69
         8.15     Benefit Plans..................................................................................70
         8.16     Enforcement of Agreement.......................................................................70
         8.17     Waiver of Jury Trial...........................................................................70
         8.18     No Presumption Against the Draftsman...........................................................71
</TABLE> 
APPENDIX A  GLOSSARY OF DEFINED TERMS/SECTION REFERENCES
 
                                    - iv -
<PAGE>
 
                                LIST OF EXHIBITS
                                ----------------
EXHIBIT
EXHIBIT A          COMPANY OPTION AGREEMENT                   Recital 7
EXHIBIT B-1        FORM OF VOTING AGREEMENT                   Recital 8
EXHIBIT B-2        FORM OF ALTERNATE VOTING AGREEMENT         Recital 8
EXHIBIT C          FORM OF COMPANY AFFILIATE AGREEMENT        4.1(p), 4.1(u),
                                                              4.4(c)(i), 3.1(t)
                                     - v -
<PAGE>
 
                          AGREEMENT AND PLAN OF MERGER

     THIS AGREEMENT AND PLAN OF MERGER (this "Agreement") is dated June 24,
1998, by and among PENEDERM INCORPORATED, a Delaware corporation (hereinafter
called the "Company"), and MLI ACQUISITION CORP., a Delaware corporation
(hereinafter called the "Merger Subsidiary") (the Company and the Merger
Subsidiary being hereinafter sometimes called the "Constituent Corporations"),
and MYLAN LABORATORIES INC., a Pennsylvania corporation (hereinafter called the
"Parent"), which is joining as a third party and is not a Constituent
Corporation.

RECITALS:

     1.     The Boards of Directors of each of the Parent and the Merger
Subsidiary have determined that it is in the best interests of the Parent and
the Merger Subsidiary and the Board of Directors of the Company has determined
that it is advisable and in the best interests of the Company and is fair to the
stockholders of the Company, for the Parent to acquire the Company upon the
terms and subject to the conditions set forth herein;

     2.     In furtherance of such acquisition, the Boards of Directors of the
Company and the Merger Subsidiary have resolved and approved that the Merger
Subsidiary be merged with and into the Company under and pursuant to the
Delaware General Corporation Law (the "DGCL") into a single corporation (the
"Merger") existing under the laws of the State of Delaware, and the Company
shall be the surviving corporation in the Merger (the Company in its capacity as
such surviving corporation being sometimes referred to herein as the "Surviving
Corporation");

     3.     The Parent, as sole shareholder of the Merger Subsidiary, and the
respective Boards of Directors of each of the Constituent Corporations and the
Parent have approved the Merger upon the terms and conditions hereinafter set
forth and have approved this Agreement;

     4.     The Merger is permitted pursuant to the DGCL;

     5.     For federal income tax purposes, it is intended that the Merger
shall qualify as a reorganization within the meaning of Section 368(a) of the
Internal Revenue Code of 1986, as amended (the "Code");

     6.     For accounting purposes, it is intended that the Merger shall be
accounted for under the purchase method;

     7.     Simultaneously with the execution and delivery of this Agreement and
as a condition and inducement to the Parent's and the Merger Subsidiary's
willingness to enter into this Agreement, the Parent is entering into a Stock
Option Agreement dated the date hereof in the form of Exhibit A (the "Company
                                                      ---------              
Option Agreement") with the Company pursuant to which the Company is granting to
the Parent the right and option to purchase 1,717,878 shares of common 

                                       1
<PAGE>
 
stock, par value $.01 per share, of the Company (the "Company Common Stock")
from the Company; and

     8.     Simultaneously with the execution and delivery of this Agreement and
as a condition and inducement to the Parent's and the Merger Subsidiary's
willingness to enter into this Agreement, the Parent is entering into Voting
Agreements in the form of Exhibit B-1 with certain members of the Board of
                          -----------                                     
Directors of the Company in their respective capacities as stockholders of the
Company and a Voting Agreement in the form of Exhibit B-2 with a member of the
                                              -----------                     
Board of Directors of the Company in his capacity as the general partner of a
limited partnership which is a stockholder of the Company (together, the "Voting
Agreements").

     NOW, THEREFORE, in consideration of the premises and the mutual agreements,
provisions and covenants herein contained and for other good and valuable
consideration, the receipt and adequacy of which are hereby acknowledged, the
parties hereto, intending to be legally bound, hereby agree that the Merger
Subsidiary shall be merged with and into the Company at the Effective Time in
accordance with the DGCL, the Company shall be the Surviving Corporation, and
the parties hereto adopt and agree to the following agreements, terms and
conditions relating to the Merger and the mode of carrying the same into effect.

1.          NAME OF SURVIVING CORPORATION, CERTIFICATE OF INCORPORATION, BYLAWS.
            ------------------------------------------------------------------- 
1.1         Name of Surviving Corporation.
            ----------------------------- 
          The name of the Surviving Corporation from and after the Effective
          Time shall be [Moon].

1.2         Certificate of Incorporation.
            ---------------------------- 

          The Certificate of Incorporation of the Company as in effect on the
          date hereof shall from and after the Effective Time be and continue to
          be the Certificate of Incorporation of the Surviving Corporation until
          changed or amended as provided by law, except that at the Effective
          Time and upon filing of the Certificate of Merger, the Certificate of
          Incorporation of the Company shall be amended and restated in its
          entirety to read identically with the Certificate of Incorporation of
          the Merger Subsidiary except that the name of the Surviving
          Corporation shall be "Penederm Incorporated" (the "Amended and
          Restated Certificate of Incorporation").

1.3         Bylaws; Directors and Officers.
            ------------------------------ 

          The Bylaws of the Company as in effect immediately prior to the
          Effective Time shall from and after the Effective Time be and continue
          to be the Bylaws of the Surviving Corporation until amended as
          provided therein.  The directors and officers of the Merger Subsidiary
          at the Effective Time shall, from and after the 

                                       2
<PAGE>
 
          effectiveness of the Merger, be the directors and officers,
          respectively, of the Surviving Corporation until their successors
          shall have been duly elected or appointed and qualified or until their
          earlier death, resignation or removal in accordance with the Surviving
          Corporation's Amended and Restated Certificate of Incorporation and
          Bylaws.

1.4         Filing of Certificate of Merger; Effective Date; Effective Time.
            --------------------------------------------------------------- 

          Upon fulfillment of the conditions set forth in Article 5 hereof (or
          at such time thereafter as provided in the Certificate of Merger), and
          if this Agreement is not thereafter, and has not theretofore been,
          terminated or abandoned as permitted by the provisions hereof, then a
          Certificate of Merger shall be filed in accordance with Section 103
          and Section 251 of the DGCL.  Said Certificate of Merger shall be
          submitted for filing in accordance with the DGCL as soon as
          practicable after the Closing.  The Merger shall become effective
          immediately upon such filing with the Secretary of State of the State
          of Delaware, which time is herein referred to as the "Effective Time"
          and which date is herein referred to as the "Effective Date."

1.5         Effects of Merger.
            ----------------- 
          The Merger shall have the effects set forth in Section 259 of the
          DGCL.

1.6         Tax-Free Reorganization.
            ----------------------- 

          The Merger is intended to be a reorganization within the meaning of
          Section 368(a) of the Code, and this Agreement is intended to be a
          "plan of reorganization" within the meaning of the regulations
          promulgated under Section 368 of the Code.

2.          STATUS AND CONVERSION OF SECURITIES.
            ----------------------------------- 

     The manner and basis of converting the shares of the capital stock of the
     Constituent Corporations in the Merger and the nature and amount of
     securities of the Parent which the holders of shares of Company Common
     Stock are to receive in exchange for such shares in the Merger are as
     follows:

2.1         Company Capital Stock.
            --------------------- 

(a)         Conversion of Company Common Stock Into Parent Common Stock.  At
the Effective Time, the shares of Company Common Stock, other than Company
Common Stock (if any) owned by the Company, the Parent or the Merger Subsidiary,
shall, by virtue of the Merger and without any action on the part of the Parent,
the Merger Subsidiary, the Company, the Surviving Corporation or the holder
thereof, automatically be cancelled

                                       3
<PAGE>
 
and be converted into shares of common stock, par value $.50 per share, of the
Parent (the "Parent Common Stock") at a ratio equal to 0.68 shares of Parent
Common Stock for each share of Company Common Stock (the "Exchange Ratio"),
subject to the provisions of Sections 2.1(b) and 2.1(d). Any shares of Company
Common Stock (if any) owned by the Company, the Parent or the Merger Subsidiary
shall be cancelled and no Parent Common Stock or other consideration shall be
delivered in exchange therefor.

(b)  Delivery of Certificates.

     (i)  The Parent shall authorize American Stock Transfer and Trust Company 
          (or such other Person or Persons as shall be reasonably acceptable to
          the Parent and the Company) to act as Exchange Agent hereunder (the
          "Exchange Agent"). As soon as practicable after the Effective Time,
          the Parent shall deposit with the Exchange Agent, in trust for the
          holders of shares of Company Common Stock converted in the Merger,
          certificates representing the shares of Parent Common Stock issuable
          pursuant to Section 2.1(a) in exchange for outstanding shares of
          Company Common Stock and cash as required to make payments in lieu of
          any fractional shares pursuant to Section 2.1(d) (such cash and shares
          of Parent Common Stock, together with any dividends or distributions
          with respect thereto, being hereinafter referred to as the "Exchange
          Fund"). The Exchange Agent shall deliver the Parent Common Stock
          contemplated to be issued pursuant to Section 2.1(a) out of the
          Exchange Fund.

    (ii)  The Parent shall instruct the Exchange Agent, as soon as practicable 
          after the Effective Time, to mail to each record holder of a
          certificate or certificates which immediately prior to the Effective
          Time represented outstanding shares of Company Common Stock converted
          in the Merger (the "Certificates") a letter of transmittal (which
          shall specify that delivery shall be effected, and risk of loss and
          title to the Certificates shall pass, only upon actual delivery of the
          Certificates to the Exchange Agent, and shall contain instructions for
          use in effecting the surrender of the Certificates in exchange for
          certificates representing shares of Parent Common Stock and cash in
          lieu of fractional shares in accordance with Section 2.1(d)). Upon
          surrender for cancellation to the Exchange Agent of all Certificates
          held by any record holder of a Certificate, together with such letter
          of transmittal, duly executed, the holder of such Certificate shall be
          entitled to receive in exchange therefor a certificate representing
          that number of whole shares of Parent Common Stock into which the
          shares 

                                       4
<PAGE>
 
          represented by the surrendered Certificate shall have been converted
          at the Effective Time pursuant to this Article 2, cash in lieu of any
          fractional share in accordance with Section 2.1(d) and certain
          dividends and other distributions in accordance with Section 2.1(c),
          and any Certificate so surrendered shall forthwith be cancelled.

(c)  Dividends; Transfer Taxes; Withholding.  No dividends or other
distributions that are declared on or after the Effective Time on Parent Common
Stock, or are payable to the holders of record thereof on or after the Effective
Time, shall be paid to any Person entitled by reason of the Merger to receive a
certificate representing Parent Common Stock until such Person surrenders the
related Certificate or Certificates, as provided in Section 2.1(b), and no cash
payment in lieu of fractional shares shall be paid to any such Person pursuant
to Section 2.1(d) until such Person shall so surrender the related Certificate
or Certificates.  Subject to the effect of applicable law, there shall be paid
to each record holder of a new certificate representing such Parent Common
Stock:  (A) at the time of such surrender or as promptly as practicable
thereafter, the amount of any dividends or other distributions theretofore paid
with respect to the shares of Parent Common Stock represented by such new
certificate and having a record date on or after the Effective Time and a
payment date prior to such surrender; (B) at the appropriate payment date or as
promptly as practicable thereafter, the amount of any dividends or other
distributions payable with respect to such shares of Parent Common Stock and
having a record date on or after the Effective Time but prior to such surrender
and a payment date on or subsequent to such surrender; and (C) at the time of
such surrender or as promptly as practicable thereafter, the amount of any cash
payable with respect to a fractional share of Parent Common Stock to which such
holder is entitled pursuant to Section 2.1(d).  In no event shall the Person
entitled to receive any such dividends or other distributions be entitled to
receive interest on such dividends or other distributions.  If any cash or
certificate representing shares of Parent Common Stock is to be paid to or
issued in a name other than that in which the Certificate surrendered in
exchange therefor is registered, it shall be a condition of such exchange that
the Certificate so surrendered shall be properly endorsed and otherwise in
proper form for transfer and that the Person requesting such exchange shall pay
to the Exchange Agent any transfer or other taxes required by reason of the
issuance of certificates for such shares of Parent Common Stock in a name other
than that of the registered holder of the Certificate surrendered, or shall
establish to the satisfaction of the Exchange Agent that such tax has been paid
or is not applicable.  The Parent or the Exchange Agent shall be entitled to
deduct and withhold from the consideration otherwise payable pursuant to this
Agreement to any holder of shares of Company Common Stock such amounts as the

                                       5
<PAGE>
 
Parent or the Exchange Agent is required to deduct and withhold with respect to
the making of such payment under the Code or under any provision of state, local
or foreign tax law.  To the extent that amounts are so withheld by the Parent or
the Exchange Agent, such withheld amounts shall be treated for all purposes of
this Agreement as having been paid to the holder of the shares of Company Common
Stock in respect of which such deduction and withholding was made by the Parent
or the Exchange Agent.

(d)  No Fractional Shares.  No certificates or scrip representing
fractional shares of Parent Common Stock shall be issuable upon the surrender
for exchange of Certificates pursuant to this Article 2, and no dividend or
other distribution or stock split of the Parent shall relate to any fractional
share, and no fractional share shall entitle the owner thereof to vote or to any
other rights of a security holder of the Parent.  In lieu of any such fractional
share, each holder of Company Common Stock who would otherwise have been
entitled to a fraction of a share of Parent Common Stock upon surrender of
Certificates for exchange pursuant to this Article 2 shall be paid an amount in
cash (without interest), rounded to the nearest cent, determined by multiplying
(i) the per-share closing price on the New York Stock Exchange, Inc. (the
"NYSE") of Parent Common Stock (as reported in the NYSE Composite Transactions)
on the Effective Date (or, if the shares of Parent Common Stock do not trade on
the NYSE on such date, the first date of trading of shares of Parent Common
Stock on the NYSE after the Effective Time) by (ii) the fractional interest to
which such holder would otherwise be entitled.  As promptly as practicable after
the determination of the amount of cash, if any, to be paid to holders of
fractional share interests, the Exchange Agent shall so notify the Parent, and
the Parent shall deposit such amount with the Exchange Agent and shall cause the
Exchange Agent to forward payments to such holders of fractional share interests
subject to and in accordance with the terms of Section 2.1(c) and this Section
2.1(d).

(e)  Return of Exchange Fund.  Any portion of the Exchange Fund which
remains undistributed to the former stockholders of the Company for twelve (12)
months after the Effective Time shall be delivered to the Parent, upon demand of
the Parent, and any such former stockholders who have not theretofore complied
with this Article 2 shall thereafter look only to the Parent for payment of
their claims for Parent Common Stock, any cash in lieu of fractional shares of
Parent Common Stock and any dividends or distributions with respect to Parent
Common Stock.  Neither the Parent nor the Surviving Corporation shall be liable
to any former holder of Company Common Stock for any such shares of Parent
Common Stock, cash and dividends and distributions held in the Exchange

                                       6
<PAGE>
 
Fund which are delivered to a public official pursuant to any applicable
abandoned property, escheat or similar law.

(f)  Adjustment of Exchange Ratio.  In the event of any
reclassification, stock split, stock dividend, or other subdivision or
combination, with respect to the Parent Common Stock, any change or conversion
of Parent Common Stock into other securities of the Parent or any other dividend
or distribution with respect to the Parent Common Stock other than normal
quarterly cash dividends as the same may be adjusted from time to time pursuant
to the terms of this Agreement (or if a record date with respect to any of the
foregoing should occur) prior to the Effective Time, appropriate and
proportionate adjustments, if any, shall be made to the Exchange Ratio, and all
references to the Exchange Ratio in this Agreement shall be deemed to be to the
Exchange Ratio as so adjusted.

(g)  No Further Ownership Rights in Company Common Stock.  All shares
of Parent Common Stock issued upon the surrender for exchange of Certificates in
accordance with the terms hereof (including any cash paid pursuant to Section
2.1(d)) shall be deemed to have been issued in full satisfaction of all rights
pertaining to the shares of Company Common Stock represented by such
Certificates.

(h)  Closing of the Company Transfer Books.  At the Effective Time, the
stock transfer books of the Company shall be closed and no transfer of shares of
Company Common Stock shall thereafter be made on the records of the Company.
If, after the Effective Time, Certificates are presented to the Surviving
Corporation, the Exchange Agent or the Parent, such Certificates shall be
cancelled and exchanged as provided in this Article 2.

(i)  Further Assurances.  If at any time after the Effective Time the
Surviving Corporation shall consider or be advised that any deeds, bills of
sale, assignments or assurances or any other acts or things are necessary,
desirable or proper (a) to vest, perfect or confirm, of record or otherwise, in
the Surviving Corporation its right, title or interest in, to or under any of
the rights, privileges, powers, franchises, properties or assets of either of
the Constituent Corporations, or (b) otherwise to carry out the purposes of this
Agreement, the Surviving Corporation and its proper officers and directors or
their designees shall be authorized to execute and deliver, in the name and on
behalf of either of the Constituent Corporations, all such deeds, bills of sale,
assignments and assurances and to do, in the name and on behalf of either
Constituent Corporation, all such other acts and things as may be necessary,
desirable or proper to vest, perfect or confirm the Surviving Corporation's
right, title or interest in, to or under any of the rights, privileges, powers,
franchises, properties or assets of such

                                       7
<PAGE>
 
Constituent Corporation and otherwise to carry out the purposes of this
Agreement.

2.2         Subsidiary Common Stock.
            ----------------------- 

          Each share of  common stock, par value $.50 per share, of the Merger
          Subsidiary (the "Subsidiary Common Stock") outstanding immediately
          prior to the Effective Time shall, by virtue of the Merger and without
          any action on the part of the holder thereof, be converted into and be
          one share of the Common Stock of the Surviving Corporation.

2.3         Assumption of Stock Options; Company Warrant; Employee Stock
            ------------------------------------------------------------
            Purchase Plan.
            ------------- 

(a)  Except as expressly provided in this Section 2.3, all rights under any
     stock option granted by the Company pursuant to its Equity Incentive Plan,
     Employee Stock Option Plan, Consultant Stock Option Plan or Nonemployee
     Directors Stock Option Plan (collectively, the "Company Stock Option
     Plans") that remains unexercised immediately prior to the Effective Time
     ("Unexercised Options") shall, together with the Company Stock Option
     Plans, be assumed by the Parent, but shall thereafter represent the right
     to acquire that number of shares of Parent Common Stock to which the
     optionee would have been entitled pursuant to the Exchange Ratio if,
     immediately prior to the Effective Time, the optionee had fully exercised
     the option and had been a stockholder of record of the Company.  The option
     price per share of Parent Common Stock shall be equal to the exercise price
     per share of the Company Common Stock under each option divided by the
     Exchange Ratio, rounded up to the nearest cent.  The Parent and the Company
     shall each take all action necessary to assure that the rights and benefits
     of the optionee under each such option shall not be increased or decreased
     by reason of this Section 2.3, and in addition, each option which is an
     incentive stock option shall be adjusted as required by Section 424 of the
     Code and the regulations promulgated thereunder so as not to constitute a
     modification, extension or renewal of the option within the meaning of
     Section 424(h) of the Code.  The duration and other terms of the options
     shall be the same as the original Company options, except that reference to
     the Company in the Company Stock Option Plans shall be deemed to be
     references to the Parent.

(b)  In the event that the Common Stock Purchase Warrant issued by the Company
     to Promethean Investment Group, L.L.C. (the "Warrant Holder"), dated
     January  21, 1998 (the "Company Warrant"), exercisable for 25,000 shares of
     Company Common Stock (the "Company Warrant Shares") has not been fully
     exercised at the Effective Time, the Company Warrant shall terminate in
     accordance with its terms.  Upon tender to the

                                       8
<PAGE>
 
     Surviving Corporation of the aggregate Purchase Price (as defined in the
     Company Warrant) then in effect under the Company Warrant, the Warrant
     Holder shall be entitled, in accordance with the terms of the Company
     Warrant, to receive that number of shares of Parent Common Stock to which
     the Warrant Holder would have been entitled pursuant to the Exchange Ratio
     if, immediately prior to the Effective Time, the Warrant Holder had fully
     exercised the Company Warrant and had been a stockholder of record of the
     Company.


(c)  On the Effective Date, the Parent shall file, and thereafter shall maintain
     the effectiveness of, a registration statement with the Securities and
     Exchange Commission (the "SEC") covering the Unexercised Options and the
     shares issuable under the Company Employee Stock Purchase Plan and the
     Company Warrant Shares and the sale of the Parent Common Stock issued upon
     exercise of the Unexercised Options and, if applicable, the termination of
     the Company Warrant.

(d)  The Employee Stock Purchase Plan of the Company (the "Company Employee
     Stock Purchase Plan") shall remain in effect, without amendment or
     modification, through the Effective Time.

2.4         Closing.
            ------- 

          After all conditions set forth in Article 5 hereof have been satisfied
          (other than those which have been expressly waived), the closing of
          the Merger (the "Closing") shall occur at the offices of Buchanan
          Ingersoll Professional Corporation, 20th Floor, One Oxford Centre,
          Pittsburgh, Pennsylvania, at which the documents to be delivered on
          the Effective Date as described in Article 5 shall be delivered by the
          respective parties.  The Closing shall be scheduled to occur on the
          date set for the Stockholders Meeting as described in Section 4.1(m)
          hereof and immediately after the Stockholders Meeting but in no event
          later than 3:00 p.m., Eastern time (the "Scheduled Closing Date").
          The Closing shall occur on the Scheduled Closing Date unless, on such
          date, any party has a right not to close the Merger and refuses to
          close, in which event the Closing shall be adjourned from Business Day
          to Business Day thereafter until the Closing occurs or until 5:01
          p.m., Eastern time, on November 30, 1998.  As used in this Agreement,
          the term "Business Day" shall mean any day on which the NYSE is open
          for trading.

3.          REPRESENTATIONS, WARRANTIES AND AGREEMENTS.
            ------------------------------------------ 
3.1         Representations, Warranties and Agreements of the Company.
            --------------------------------------------------------- 
          The Company represents and warrants to the Parent and the Merger
          Subsidiary as follows:

                                       9
<PAGE>
 
(a)  Organization, Standing and Power.

     (i)  The Company is a corporation duly organized, validly existing and in 
          good standing under the laws of the State of Delaware with all
          requisite corporate power and authority to own, operate and lease its
          properties, to carry on its business as now being conducted, to enter
          into this Agreement and, subject to the approval of the Company's
          stockholders in accordance with the DGCL, to perform its obligations
          hereunder. The Company is duly qualified or licensed to do business
          and in good standing in the state of California and in each other
          jurisdiction which the property owned, leased or operated by it or the
          nature of the business conducted by it makes such qualification or
          licensing necessary, except where the failure to be so qualified or so
          licensed would not, individually or in the aggregate, have a Material
          Adverse Effect on the Company. For purposes of this Agreement,
          "Material Adverse Change" or "Material Adverse Effect" means, when
          used with respect to the Parent or the Company, as the case may be,
          any event, circumstance, change or effect that is or could reasonably
          be expected (as far as can be foreseen at the time) to be so adverse
          as to result in a severe and critical impairment of the business,
          assets, liabilities, financial condition or results of operations of
          the Parent and its Subsidiaries, taken as a whole, or the Company and
          PL, taken as a whole, as the case may be.

     (ii) The Company has only one subsidiary, Penederm Limited (Company No.
          3076653), a company incorporated in England and Wales ("PL"). PL is a
          corporation duly organized and validly existing under the laws of
          England and Wales with all corporate power and authority to own,
          operate and lease its properties and to carry on its business as now
          being conducted. The authorized share capital of PL is (Pounds)1,000
          divided into 1,000 shares of (Pounds)1 each. All of the issued and
          outstanding shares of PL are allotted to the Company free and clear of
          all security interests, liens, claims, pledges, charges or other
          encumbrances of any nature whatsoever, and all such shares have been
          validly issued, fully paid and nonassessable and free of preemptive
          rights. There are no outstanding rights, options, warrants, conversion
          rights or agreements for the purchase or acquisition from, or the sale
          or issuance by, PL of any of its shares.

(b)  Capital Structure.

     (i)  As of the date hereof, the authorized capital stock of the Company 
          consists of 30,000,000 shares of Company Common Stock and

                                       10
<PAGE>
 
          10,000,000 shares of preferred stock, par value $.01 per share (the
          "Company Preferred Stock"). At the close of business on June 15, 1998,
          8,620,203 shares of Company Common Stock were issued and outstanding,
          all of which were validly issued, fully paid and nonassessable, and
          free of preemptive rights. As of the date hereof: (A) no shares of
          Company Common Stock are held in the treasury of the Company or PL;
          (B) 1,487,664 shares of Company Common Stock are reserved for future
          issuance pursuant to the Company Stock Option Plans; (C) 25,000 shares
          are reserved for issuance under the Company Warrant; (D) 727,518
          shares are reserved for issuance under that certain Common Stock
          Investment Agreement dated as of January 21, 1998 between Promethean
          Investment Group L.L.C. (the "Investor") and the Company (the "Common
          Stock Investment Agreement"); (E) 70,516 shares are reserved for
          issuance under the Company Employee Stock Purchase Plan; and (F)
          30,000 shares are reserved for issuance under the 401(k) Plan of the
          Company (the "Company 401(k) Plan"). The Company Stock Option Plans,
          the Company Warrant, the Common Stock Investment Agreement, the
          Company Employee Stock Purchase Plan and the Company 401(k) Plan are
          the only benefit plans or arrangements of the Company or PL under
          which any securities of the Company or PL are issuable. No shares of
          Company Preferred Stock are issued and outstanding. As of the date of
          this Agreement, except as set forth above, no shares of capital stock
          or other voting securities of the Company or PL are issued, reserved
          for issuance or outstanding. As of the date of this Agreement, except
          for stock options covering not in excess of 1,220,097 shares of
          Company Common Stock issued under the Company Stock Option Plans
          (collectively, the "Company Stock Options"), the Company Warrant and
          rights to purchase covering approximately 10,000 shares of Company
          Common Stock under the Company Employee Stock Purchase Plans and the
          Company's matching contribution obligations under the 401(k) Plan,
          there are no options, warrants, calls, rights or agreements to which
          the Company or PL is a party or by which either of them is bound
          obligating the Company or PL to issue, deliver or sell, or cause to be
          issued, delivered or sold, additional shares of capital stock of the
          Company or PL or obligating the Company or PL to grant, extend or
          enter into any such option, warrant, call, right or agreement. The
          Company does not have any outstanding bonds, debentures, notes or
          other obligations the holders of which have the right to vote (or
          convertible into or exercisable for securities having the right to
          vote) with the stockholders of the Company on any matter. There are no
          obligations, contingent or otherwise, of the Company to (x)
          repurchase, redeem or otherwise acquire any

                                       11
<PAGE>
 
          shares of Company Common Stock or other capital stock of the Company,
          or the capital stock or other equity interests of PL; (y) (other than
          advances to PL in the ordinary course of business) provide material
          funds to, or make any material investment in (in the form of a loan,
          capital contribution or otherwise), or provide any guarantee with
          respect to the obligations of, PL or any other Person; or (z) make
          payment of any Shortfall Compensation (as defined in the Common Stock
          Investment Agreement) to the Investor. The Company contributed 4,651
          shares of Company Common Stock to the Company 401(k) Plan in respect
          of the plan year ended December 31, 1997.

     (ii) The Company has made available to the Parent complete and correct 
          copies of the Company Stock Option Plans, the Company Employee Stock
          Purchase Plan, the Common Stock Investment Agreement, the Company
          401(k) Plan and the Company Warrant. Schedule 3.1(b) sets forth a
                                               ---------------  
          complete and accurate list of (A) all Company Stock Options
          outstanding as of the date of this Agreement and (B) the exercise
          price of each outstanding Company Stock Option.

(c)  Authority.  On or prior to the date of this Agreement, the Board of 
     Directors of the Company has determined the Merger to be advisable and fair
     to and in the best interest of the Company and its stockholders, approved
     this Agreement in accordance with the DGCL, resolved (subject to its
     fiduciary duties) to recommend the approval of this Agreement by the
     Company's stockholders and directed that this Agreement be submitted to the
     Company's stockholders for approval. The Company has all requisite
     corporate power and authority to enter into this Agreement and the Company
     Option Agreement, to consummate the transactions contemplated by the
     Company Option Agreement and, subject to approval by the stockholders of
     the Company of this Agreement, to consummate the transactions contemplated
     hereby. The execution and delivery of this Agreement and the Company Option
     Agreement by the Company and the consummation by the Company of the
     transactions contemplated hereby and thereby have been duly authorized by
     all necessary corporate action on the part of the Company, subject, in the
     case of this Agreement, to (x) approval of this Agreement by the
     stockholders of the Company and (y) the filing of a Certificate of Merger
     as required by the DGCL. This Agreement and the Company Option Agreement
     have been duly executed and delivered by the Company and (assuming the
     valid authorization, execution and delivery of this Agreement by the Parent
     and the Merger Subsidiary and the Company Option Agreement by the Parent
     and the validity and binding effect of this Agreement on the Parent and the
     Merger Subsidiary and the Company Option Agreement on the Parent)
     constitute

                                       12
<PAGE>
 
     the valid and binding obligation of the Company enforceable against the
     Company in accordance with their respective terms, except to the extent
     that enforceability thereof may be limited by applicable bankruptcy,
     insolvency, reorganization or other similar laws affecting the enforcement
     of creditors' rights generally and by principles of equity regarding the
     availability of remedies. The Company has taken all necessary action to
     render its Shareholders Rights Plan dated November 20, 1996 (the "Company
     Rights Plan") inapplicable to the transactions contemplated by this
     Agreement. The filing of a combined prospectus and proxy statement to be
     included in the Registration Statement (together with any amendments or
     supplements thereto, the "Prospectus/Proxy Statement") with the SEC and the
     issuance of the shares of Company Common Stock pursuant to the Company
     Option Agreement have been duly authorized by the Company's Board of
     Directors.


(d)  Consents and Approvals; No Violation.  Assuming that all consents, 
     approvals, authorizations and other actions described in this Section
     3.1(d) have been obtained and all filings and obligations described in this
     Section 3.1(d) have been made, except as set forth on Schedule 3.1(d), the
                                                           ---------------
     execution and delivery of this Agreement and the Company Option Agreement
     do not, and the consummation of the transactions contemplated hereby and
     thereby and compliance with the provisions hereof and thereof will not,
     result in any violation of, or default (with or without notice or lapse of
     time, or both) under, or give to others a right of termination,
     cancellation or acceleration of any obligation or the loss of a material
     benefit under, or result in the creation of any lien, security interest,
     charge or encumbrance upon any of the properties or assets of the Company
     or PL under, any provision of (i) the Certificate of Incorporation or
     Bylaws of the Company, (ii) any provision of the charter or organization
     documents of PL, (iii) any loan or credit agreement, note, bond, mortgage,
     indenture, lease or other agreement, instrument, permit, concession,
     franchise or license applicable to the Company or PL, including, without
     limitation, the intellectual property listed on Schedule 3.1(x) and the in-
                                                     ---------------
     licenses, out-licenses, co-promotion and co-marketing agreements listed on
     Schedule 3.1(bb), or (iv) any judgment, order, decree, statute, law,
     ----------------
     ordinance, rule or regulation applicable to the Company or PL or any of
     their respective properties or assets, other than, in the case of clauses
     (ii), (iii) or (iv), any such violations, defaults, rights, liens, security
     interests, charges or encumbrances that, individually or in the aggregate,
     would not have a Material Adverse Effect on the Company, materially impair
     the ability of the Company to perform its obligations hereunder or under
     the Company Option Agreement or prevent the consummation of any of the
     transactions contemplated hereby or thereby. No filing or registration
     with, or authorization, consent or approval of, any domestic (federal and
     state), foreign or supranational court, commission, governmental body,

                                       13
<PAGE>
 
     regulatory agency, authority or tribunal (a "Governmental Entity") is
     required by or with respect to the Company or PL in connection with the
     execution and delivery of this Agreement or the Company Option Agreement by
     the Company or is necessary for the consummation of the Merger and the
     other transactions contemplated by this Agreement or the Company Option
     Agreement, except for (i) in connection, or in compliance, with the
     provisions of the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as
     amended (the "HSR Act"), the Securities Act of 1933, as amended (together
     with the rules and regulations promulgated thereunder, the "Securities
     Act") and the Securities Exchange Act of 1934, as amended (together with
     the rules and regulations promulgated thereunder, the "Exchange Act"), (ii)
     the filing of the Certificate of Merger with the Secretary of State of the
     State of Delaware and appropriate documents with the relevant authorities
     of other states in which the Company is qualified to do business, (iii)
     such filings, registrations, authorizations, consents or approvals as may
     be required with respect to PL, (iv) applicable requirements, if any, of
     the National Association of Securities Dealers ("NASD") and the National
     Association of Securities Dealers Automated Quotation National System
     ("NASDAQ"), (v) as may be required under foreign laws, (vi) the consents
     and approvals listed on Schedule 3.1(d), and (vii) such other consents,
                             ---------------
     orders, authorizations, registrations, declarations and filings the failure
     of which to be obtained or made would not, individually or in the
     aggregate, have a Material Adverse Effect on the Company, materially impair
     the ability of the Company to perform its obligations hereunder or under
     the Company Option Agreement or prevent the consummation of any of the
     transactions contemplated hereby or thereby.

(e)  SEC Documents and Other Reports.  The Company has filed all required 
     documents with the SEC since January 1, 1995 (the "Company SEC Documents").
     As of their respective dates, the Company SEC Documents complied in all
     material respects with the requirements of the Securities Act or the
     Exchange Act, as the case may be, and, at the respective times they were
     filed, none of the Company SEC Documents contained any untrue statement of
     a material fact or omitted to state a material fact required to be stated
     therein or necessary to make the statements therein, in light of the
     circumstances under which they were made, not misleading. The consolidated
     financial statements (including, in each case, any notes thereto) of the
     Company included in the Company SEC Documents (the "Company Financial
     Statements") as of their respective dates complied as to form in all
     material respects with applicable accounting requirements and the published
     rules and regulations of the SEC with respect thereto, were prepared in
     accordance with generally accepted accounting principles (except, in the
     case of the unaudited statements, as permitted by Form 10-Q of the SEC)
     applied on a consistent basis during the periods involved

                                       14
<PAGE>
 
     (except as may be indicated therein or in the notes thereto) and fairly
     presented in all material respects the consolidated financial position of
     the Company and PL as at the respective dates thereof and the consolidated
     results of their operations and their consolidated cash flows for the
     periods then ended. Except as disclosed in the Company SEC Documents or as
     required by generally accepted accounting principles, the Company has not,
     since March 31, 1998, made any change in the accounting practices or
     policies applied in the preparation of the Company Financial Statements.
     Neither the Company nor PL had as of March 31, 1998 any liabilities or
     obligations of any nature, whether or not accrued, contingent or otherwise,
     that would be required by generally accepted accounting principles to be
     reflected on the consolidated balance sheet of the Company and PL at March
     31, 1998 (including the notes thereto) included in the Company Financial
     Statements that are not so reflected.

(f)  Registration Statement and Prospectus/Proxy.  None of the information to 
     be supplied by the Statement Company (as to the Company) for inclusion or
     incorporation by reference in the Registration Statement or the
     Prospectus/Proxy Statement will (i) in the case of the Registration
     Statement, at the time it becomes effective, contain any untrue statement
     of a material fact or omit to state any material fact required to be stated
     therein or necessary in order to make the statements therein not misleading
     or (ii) in the case of the Prospectus/Proxy Statement, at the time of the
     mailing of the Prospectus/Proxy Statement, at the time of the Stockholders
     Meeting and at the Effective Time, contain any untrue statement of a
     material fact or omit to state any material fact required to be stated
     therein or necessary in order to make the statements therein, in light of
     the circumstances under which they are made, not misleading. If, at any
     time prior to the Effective Time, any event with respect to the Company,
     its officers and directors or PL shall occur which is required at that time
     to be described in the Prospectus/Proxy Statement, such event shall be so
     described, and an appropriate amendment or supplement shall be promptly
     filed with the SEC and, as required by law, disseminated to the
     stockholders of the Company. The Prospectus/Proxy Statement will comply
     (with respect to the Parent) as to form in all material respects with the
     provisions of the Securities Act, and (with respect to the Company) as to
     form in all material respects with the provisions of the Exchange Act.


(g)  Absence of Certain Changes or Events.  Except as disclosed in the
     Company SEC Documents filed with the SEC prior to the date of this
     Agreement, since March 31, 1998 and except as set forth on Schedule 3.1(g),
                                                                ----------------
     (i) the Company and PL have not incurred any material liability or
     obligation (indirect, direct or contingent), or entered into any material
     oral or written agreement or other transaction, that is not in the ordinary
     course of business consistent with past practice or that would

                                       15
<PAGE>
 
     result in a Material Adverse Effect on the Company; (ii) the Company and PL
     have not sustained any loss or interference with their business or
     properties from fire, flood, windstorm, accident or other calamity (whether
     or not covered by insurance) that has had a Material Adverse Effect on the
     Company; (iii) there has been no change in the capital stock of the Company
     except for the issuance of shares of Company Common Stock pursuant to
     Company Stock Options and the Company Employee Stock Purchase Plan and no
     dividend or distribution of any kind declared, paid or made by the Company
     on any class of its stock; (iv) there has not been (A) any granting by the
     Company or PL to any executive officer of the Company or PL of any increase
     in compensation, except in the ordinary course of business consistent with
     prior practice or as was required under employment agreements in effect as
     of the date of the most recent audited financial statements included in the
     Company SEC Documents, (B) any granting by the Company or PL to any such
     executive officer of any increase in severance or termination agreements in
     effect as of the date of the most recent audited financial statements
     included in the Company SEC Documents, or (C) any entry by the Company or
     PL into any employment, severance or termination agreement with any such
     executive officer; (v) any delivery of a "put notice," as defined in the
     Common Stock Investment Agreement, or any issuance of any shares of Company
     Common Stock pursuant to the Common Stock Investment Agreement; and (vi)
     there has been no event causing a Material Adverse Effect on the Company or
     any developments that would, individually or in the aggregate, result in a
     Material Adverse Effect on the Company.

(h)  Permits and Compliance.  Each of the Company and PL is in possession of 
     all franchises, grants, authorizations, licenses, permits, easements,
     variances, exceptions, consents, certificates, approvals and orders of any
     Governmental Entity necessary for the Company or PL to own, lease and
     operate its properties or to carry on its business as it is now being
     conducted (the "Company Permits"), except where the failure to have any of
     the Company Permits would not, individually or in the aggregate, have a
     Material Adverse Effect on the Company, and, as of the date of this
     Agreement, no suspension or cancellation of any of the Company Permits is
     pending or, to the knowledge of the Company, threatened, except where the
     suspension or cancellation of any of the Company Permits would not,
     individually or in the aggregate, have a Material Adverse Effect on the
     Company. Neither the Company nor PL is in violation of (i) its charter, by-
     laws or other organizational documents, (ii) any applicable law, ordinance,
     administrative or governmental rule or regulation, or (iii) any order,
     decree or judgment of any Governmental Entity having jurisdiction over the
     Company or PL, except, in the case of clauses (i), (ii) and (iii), for any
     violations that, individually or in the aggregate, would not have a
     Material Adverse Effect on the Company. Except as set forth in the

                                       16
<PAGE>
 
     Company SEC Documents filed prior to the date of this Agreement, no event
     of default or event that, but for the giving of notice or the lapse of time
     or both, would constitute an event of default exists or, upon the
     consummation by the Company of the transactions contemplated by this
     Agreement or the Company Option Agreement, will exist under any indenture,
     mortgage, loan agreement, note or other agreement or instrument for
     borrowed money, any guarantee of any agreement or instrument for borrowed
     money or any lease, contractual license or other agreement or instrument to
     which the Company or PL is a party or by which the Company or PL is bound
     or to which any of the properties, assets or operations of the Company or
     PL is subject, other than any defaults that, individually or in the
     aggregate, would not have a Material Adverse Effect to on the Company. On
     May 13, 1998, the Company's revolving credit facility with Silicon Valley
     Bank terminated in accordance with the terms thereof, the Company having
     satisfied in full all of its obligations thereunder.


(i)  Tax Matters.  Except as set forth on Schedule 3.1(i), (i) the
                                          ---------------         
     Company and PL have filed all federal, and all material state, local,
     foreign and provincial, Tax Returns required to have been filed or
     appropriate extensions therefor have been properly obtained, and such Tax
     Returns are correct and complete, except to the extent that any failure to
     so file or any failure to be correct and complete would not, individually
     or in the aggregate, have a Material Adverse Effect on the Company; (ii)
     all Taxes shown to be due on such Tax Returns have been timely paid or
     extensions for payment have been properly obtained; (iii) the Company and
     each of its Subsidiaries have complied in all material respects with all
     rules and regulations relating to the withholding of Taxes except to the
     extent that any failure to comply with such rules and regulations would
     not, individually or in the aggregate, have a Material Adverse Effect on
     the Company; (iv) neither the Company nor PL has waived or extended any
     statute of limitations in respect of its Taxes; (v) to the knowledge of the
     Company, no Tax Returns referred to in clause (i) relating to federal and
     state income Taxes have been examined by the Internal Revenue Service
     ("IRS") or the appropriate state taxing authority for any period; (vi) no
     issues have been raised in writing by the relevant taxing authority in
     connection with the examination of the Tax Returns referred to in clause
     (i); (vii) all deficiencies asserted or assessments made as a result of any
     examination of such Tax Returns by any taxing authority have been paid in
     full or are being timely and properly contested; and (viii) the Company is
     not a "United States real property holding company" as defined in Section
     897(c) of the Code. The Company has not filed a consent of the type
     described in Section 341(f) of the Code. The Company is not and has never
     been a member of an affiliated group of corporations (within the meaning of
     Section 1504 of the Code). The

                                       17
<PAGE>
 
     Company is not a party to, is not bound by and does not have any obligation
     under any tax sharing, tax indemnity or similar agreement. For purposes of
     this Agreement: (i) "Taxes" means any federal, state, local, foreign or
     provincial income, gross receipts, property, sales, use, license, excise,
     franchise, employment, payroll, withholding, alternative or added minimum,
     ad valorem, value-added, transfer or excise tax, or other tax, custom,
     duty, governmental fee or other like assessment or charge of any kind
     whatsoever, together with any interest or penalty imposed by any
     Governmental Entity, and (ii) "Tax Return" means any return, report or
     similar statement (including the attached schedules) required to be filed
     with respect to any Tax, including, without limitation, any information
     return, claim for refund, amended return or declaration of estimated Tax.


(j)  Actions and Proceedings.  Except as set forth in the Company SEC
     Documents filed prior to the date of this Agreement or on Schedule 3.1(j),
                                                               ---------------
     there are no outstanding orders, judgments, injunctions, awards or decrees
     of any Governmental Entity against or involving the Company or PL, or
     against or involving any of its or their present or, to the knowledge of
     the Company, former directors, officers, employees, consultants or agents
     of the Company or PL, in their capacities as such, any of its or their
     properties, assets or business or any Employee Benefit Plan of the Company
     that, individually or in the aggregate, would have a Material Adverse
     Effect on the Company or materially impair the ability of the Company to
     perform its obligations hereunder or under the Company Option Agreement. As
     of the date of this Agreement, there are no actions, suits, labor disputes
     or claims or legal, administrative or arbitrative proceedings or
     governmental investigations pending or, to the knowledge of the Company,
     threatened against or involving the Company or PL or any of its or their
     present or, to the knowledge of the Company, former directors, officers,
     employees, consultants or agents in their capacities, as such, or any of
     its or their properties, assets or business or any Employee Benefit Plan of
     the Company that, individually or in the aggregate, would have a Material
     Adverse Effect on the Company or materially impair the ability of the
     Company to perform its obligations hereunder or under the Company Option
     Agreement. As of the date hereof, there are no actions, suits, labor
     disputes or other litigation, legal or administrative proceedings or
     governmental investigations pending or, to the knowledge of the Company,
     threatened against or affecting the Company or PL or any of its or their
     present or, to the knowledge of the Company, former officers, directors,
     employees, consultants or agents, in their capacities as such, or any of
     its or their properties, assets or business relating to the transactions
     contemplated by this Agreement and the Company Option Agreement. For
     purposes of this Agreement, the term "knowledge of the Company" shall mean
     the actual knowledge of the officers and directors of the Company.

                                       18
<PAGE>
 
(k)  FDA and Related Matters.

(i)  Schedule 3.1(k) sets forth a list, for the period between January 1, 1993
     ---------------                                                          
     and the date hereof, of (A) all Regulatory or Warning Letters, Notices of
     Adverse Findings and Section 305 Notices and similar letters or notices
     issued by the Food and Drug Administration ("FDA") (or any other federal,
     state, local or foreign governmental entity that is concerned with the
     safety, efficacy, reliability or manufacturing of drug products (each, a
     "Drug Regulatory Agency")) to the Company or PL that, individually or in
     the aggregate, would have a Material Adverse Effect on the Company, (B) all
     product recalls, notifications and safety alerts conducted by the Company
     or PL, whether or not required by the FDA, and any request from the FDA or
     any Drug Regulatory Agency requesting the Company or PL to cease to
     investigate, test or market any product, which recalls, notifications,
     safety alerts or requests would, individually or in the aggregate, have a
     Material Adverse Effect on the Company, and (C) any criminal, injunctive,
     seizure or civil penalty actions begun or threatened by the FDA or any Drug
     Regulatory Agency against the Company or PL and known by the Company or PL
     and all related consent decrees (including plea agreements) issued with
     respect to the Company or PL.  Copies of all documents referred to in
     Schedule 3.1(k) have been made available to the Parent.
     ---------------                                        

(ii) The Company has made submissions to obtain material approvals,
     certifications, authorizations, clearances and permits for marketing, and
     has made filings with, or notifications to, the FDA and Drug Regulatory
     Agencies (or has documented a basis for not making such filings or
     notifications) pursuant to applicable requirements of the Federal Food,
     Drug and Cosmetics Act, as amended (the "FDA Act"), and applicable laws,
     regulations and rules with respect to each of the products sold by the
     Company or PL that is listed on Schedule 3.1(k).  The products listed on
                                     ---------------                         
     Schedule 3.1(k) collectively constitute in excess of 95% of the gross
     ---------------                                                      
     revenues generated during the twelve (12)-month period ending December 31,
     1997 by that portion of the business of the Company and PL which is subject
     to the jurisdiction of the FDA or any Drug Regulatory Agency.  The Company
     and PL have no reason to believe that any of the material approvals,
     clearances, authorizations, registrations, certifications, permits, filings
     or notifications that it or any of its Subsidiaries has received or made to
     the FDA or any Drug Regulatory Agency that relate to the marketing of the
     products listed on Schedule 3.1(k) have been or are being revoked;
                        ---------------                                
     provided, however, the FDA or any other Drug

                                       19
<PAGE>
 
      Regulatory Agency may disagree with the Company's or PL's assessment and
      undertake actions, at any time, to remove from commercial distribution any
      such product.

(iii) Except as disclosed on Schedule 3.1(k), neither the Company nor PL
                             ---------------                          
has knowledge (or has been notified by the Contract Manufacturer) of any pending
regulatory action of any sort (other than non-material routine or periodic
inspections or reviews) against any of the Company, PL or the contract
manufacturer of the Company's products (the "Contract Manufacturer") by the FDA
or any Drug Regulatory Agency or any other duly authorized governmental
authority which regulates the sale of drugs in any jurisdiction which could have
a Material Adverse Effect on the Company or in any material way limit or
restrict the ability of the Company or PL to market existing products.  Except
as set forth on Schedule 3.1(k), none of the Company, PL or, to the knowledge of
                ---------------                                                 
the Company, the Contract Manufacturer has knowingly committed or permitted to
exist any violation of the rules and regulations of the FDA or any Drug
Regulatory Agency or any other duly authorized governmental authority which
regulates the sale of drugs which has not been cured by the Company, PL or, to
the knowledge of the Company, the Contract Manufacturer or waived by the FDA or
any such regulatory authority; provided, however, the FDA or any other Drug
Regulatory Agency may disagree with the Company's assessment and undertake
enforcement actions at any time.

(l)  Certain Agreements.  Except as set forth in Schedule 3.1(l), neither
                                                 ---------------
     the Company nor PL is a party to any oral or written employment agreement
     or plan, including any employment agreement, severance agreement, stock
     option plan, stock appreciation rights plan, restricted stock plan or stock
     purchase plan, any of the benefits of which shall be increased, or the
     vesting of the benefits of which will be accelerated, by the occurrence of
     any of the transactions contemplated by this Agreement or the Company
     Option Agreement or the value of any of the benefits of which will be
     calculated on the basis of any of the transactions contemplated by this
     Agreement or the Company Option Agreement (collectively, "Transaction
     Agreements"). No holder of any option to purchase shares of Company Common
     Stock, or shares of Company Common Stock granted in connection with the
     performance of services for the Company or PL, is or will be entitled to
     receive cash from the Company or PL in lieu of or in exchange for such
     option or shares as a result of the transactions contemplated by this
     Agreement or the Company Option Agreement. Schedule 3.1(l) sets forth (i)
                                                --------------
     for each officer, director or employee who is a party to, or will receive
     benefits (other than as a result of Section 2.3)

                                       20
<PAGE>
 
     under, any Transaction Agreement, the total amount that each such Person
     may receive, or is eligible to receive, assuming that the transactions
     contemplated by this Agreement are consummated on the date hereof, and (ii)
     the total amount of indebtedness owed to the Company or PL from each
     officer or director of the Company and PL. Except as set forth in the
     Certificate of Incorporation and Bylaws of the Company or PL, neither the
     Company nor PL is a party to any indemnification agreement with any of its
     present or future directors, officers, employees, agents or other Persons
     who serve or served in any other capacity with any other enterprise at the
     request of the Company or of PL.

(m)  Material Contracts.  Except as set forth in Schedule 3.1(m) or on any
                                                 ---------------
     other Schedule hereto, as of the date hereof, neither the Company nor PL is
     a party to, or is bound by, (i) any material agreement, indenture or other
     instrument relating to the borrowing of money by the Company or PL or the
     guarantee by the Company or PL of any such obligation (other than trade
     payables and instruments relating to transactions entered into in the
     ordinary course of business) or (ii) any other material contract or
     agreement or amendment thereto that (A) is not described in, or filed as an
     exhibit to, a Form 10-K, a Form 10-Q or a Form 8-K filed by the Company
     with the SEC, (B) places any material restrictions on the ability of the
     Company to engage in any material business activity currently conducted, or
     (C) is material to the business, properties, assets, liabilities, financial
     condition, results of operations or prospects of the Company and PL, taken
     as a whole (collectively, the "Company Contracts"). Neither the Company nor
     PL is in default under any Company Contract, which default is reasonably
     likely to have, either individually or in the aggregate, a Material Adverse
     Effect on the Company, and there has not occurred any event that with the
     lapse of time or the giving of notice or both would constitute such a
     default.


(n)  Opinion of Financial Advisor.  The Company has received the written 
     opinion of Lehman Brothers Inc., dated the date hereof, to the effect that,
     as of the date hereof, from a financial point of view, the Exchange Ratio
     to be offered to the stockholders of the Company is fair to the Company's
     stockholders, a copy of which opinion has been delivered to the Parent.

(o)  Takeover Provisions Inapplicable.  As of the date hereof and at all times 
     on or prior to the Effective Time, Section 203 of the DGCL is, and shall
     be, inapplicable to the Merger, the Company Option Agreement, the Voting
     Agreements and the transactions contemplated thereby.

(p)  Required Vote of the Company Stockholders.  The affirmative vote of the 
     holders of a majority of the outstanding shares of Company Common Stock is
     required to adopt this Agreement. No other vote of the

                                       21
<PAGE>
 
     securityholders of the Company is required by law, the Certificate of
     Incorporation or Bylaws of the Company or otherwise in order for the
     Company to consummate the Merger and the transactions contemplated hereby
     and in the Company Option Agreement.


(q)  Finders and Investment Bankers.  Except for Lehman Brothers, Inc., whose 
     fees will be paid by the Company, there is no investment banker, broker,
     finder or other intermediary which has been retained by or is authorized to
     act on behalf of the Company or PL who might be entitled to any fee or
     commission in connection with the transactions contemplated by this
     Agreement.

(r)  Authorized Stock.  The Company has taken all necessary corporate
     and other action to authorize and reserve and to permit it to issue, and,
     at all times from the date hereof until the obligation to deliver Common
     Stock when the Company Option Agreement terminates, will have reserved for
     issuance, upon exercise of the Option (as defined in the Company Option
     Agreement), shares of Common Stock necessary for the Parent to exercise the
     Option, and the Company shall take all necessary corporate action to
     authorize and reserve for issuance all additional shares of Common Stock or
     other securities which may be issued pursuant to the Company Option
     Agreement upon exercise of the Option. The shares of Common Stock to be
     issued upon due exercise of the Option, including all additional shares of
     Common Stock or other securities which may be issuable pursuant to the
     Company Option Agreement, upon issuance pursuant thereto, shall be duly and
     validly issued, fully paid and nonassessable and shall be delivered free
     and clear of all liens or encumbrances of any kind or nature whatsoever,
     including any preemptive rights of any stockholder.

(s)  Company Affiliates.  Schedule 3.1(s) contains a list (reasonably
                          ---------------
     satisfactory to counsel for the Parent) identifying all Persons who may be
     deemed to be "affiliates" of the Company on the date hereof as that term is
     used in paragraphs (c) and (d) of Rule 145 under the Securities Act (the
     "Company Affiliates").

(t)  Owned Real Property.  The Company owns no real property.

(u)  Leased Real Estate.  The Company is the lessee under the real estate
     leases described on Schedule 3.1(u). Schedule 3.1(u) contains the number of
                         ---------------  ---------------
     square feet leased by the Company under each lease, the current rent
     payable thereunder and the expiration date of each lease. True, correct and
     complete copies of said leases have been delivered by the Company to the
     Parent. The Company now enjoys quiet and undisturbed possession under each
     of said leases. To the knowledge of the Company, such leased real estate is
     free and clear of any zoning, use or building restriction or any

                                       22
<PAGE>
 
     pending, proposed or threatened zoning or use or building restriction which
     would, either singly or in the aggregate, adversely interfere with the
     present or any intended use of any of such leased real estate. To the
     knowledge of the Company, said leases are valid and binding and in full
     force and effect. The Company is not in default as to the payment of rent
     and has not received written notice of any other default thereunder.


(v)  Owned and Leased Tangible Personal Property.  Title to all of the 
     Company's owned equipment, vehicles, furniture and fixtures and other items
     of owned tangible personal property is held by the Company free and clear
     of any claim, lease, mortgage, security interest, conditional sale
     agreement or other title retention agreement, restriction or lien or
     encumbrance of any kind or nature whatsoever, except as set forth on
     Schedule 3.1(v). The Company has a valid leasehold interest in all tangible
     ---------------
     personal property material to its business held by it under lease, and
     true, correct and complete copies of said leases have been delivered by the
     Company to the Parent. To the knowledge of the Company, said leases are
     valid and binding and in full force and effect. The Company is not in
     default as to the payment of rent and has not received written notice of
     any other default thereunder.

(w)  Physical Condition of Property.  To the knowledge of the Company, all of 
     the leased real estate of the Company and the structures erected thereon
     and all of the owned and leased tangible personal property of the Company
     are in good repair and condition and are suitable for the conduct of the
     present business of the Company.

(x)  Patents and Certain Other Intellectual Property Rights.


(i)  Schedule 3.1(x) lists all of the patents (including all reissues,
     ---------------                                                  
     divisions, continuations and extensions thereof), patent applications,
     patent disclosures, docketed inventions, trademarks, trademark
     applications, trade names and copyrights owned by the Company.

(ii) The Company owns, or possesses the right to use, all of the intellectual
     property rights necessary to the conduct of the business of the Company as
     presently conducted except for rights which, if not so owned or possessed,
     would not individually or in the aggregate have a Material Adverse Effect
     on the Company.  Such ownership or right to use, as the case may be, is
     free and clear of all liens, security interests, claims and rights to use
     of third parties except those which would not, individually or in the
     aggregate, have a Material Adverse Effect on the Company.

                                       23
<PAGE>
 
(iii)Except pursuant to licenses listed in Schedule 3.1(bb) or in the Company 
                                           ----------------
     SEC Documents, there are no material royalties, honoraria, fees or other
     payments payable as of the date hereof by the Company to any person by
     reason of the ownership, use, license, sale or disposition of any of the
     Company's intellectual property rights.

(iv) The Company is not, to the knowledge of the Company, infringing the right
     of any other party with respect to any intellectual property rights which
     would, individually or in the aggregate, be reasonably likely to have a
     Material Adverse Effect on the Company.

(y)  Accounts Receivable.  No customer(s) representing 10% or more of the 
     total revenues of the Company is (are) delinquent in the payment of its
     (their) accounts with the Company.

(z)  Insurance and Bonds.  Attached hereto, made part hereof and marked 
     Schedule 3.1(z) is a true and correct listing of all of the policies of
     ---------------
     insurance and all surety and other bonds to which the Company now is a
     party, or during the immediately preceding sixty (60) months was a party.
     All of such policies and bonds which have expired were valid and in full
     force and effect during their respective terms, all other of such policies
     and bonds are valid and in full force and effect at the present time, and
     no claim has been made, or notice given, to cancel or avoid any of said
     policies or bonds or to reduce the coverage provided thereby, except where
     the existence of any claim or notice of cancellation, avoidance or
     reduction of coverage, or invalidity, unenforceability or ineffectiveness,
     would not have a Material Adverse Effect on the Company.

(aa) Product Warranties and Liability.


(i)  No reserves have been provided for by the Company to cover potential claims
     under existing customer indemnification agreements.

(ii) Except as to claims, actions, proceedings or investigations which have been
     asserted but as to which no notice has been given to the Company, and
     except as set forth on Schedule 3.1(aa), there are no product liability
                            ----------------                                
     claims, actions, proceedings or investigations pending or, to the knowledge
     of the Company, threatened against the Company or its assets or state of
     facts existing which could give rise to any such product liability claim,
     action, proceeding or investigation.

(iii)To the knowledge of the Company, no claims have been made that the 
     products sold by the Company are not effective for the uses

                                       24
<PAGE>
 
     such products purport to serve. To its knowledge, the Company has not
     received any written notice that any product manufactured by it has not
     been manufactured in accordance with "current Good Manufacturing Practices"
     (as such term is commonly understood within the Company's industry) or has
     not been properly labeled for its approved use.

(bb) Contracts, Proposals and Bids.  Schedule 3.1(bb) is a list of all of the
                                     ----------------
     in-license, out-license, co-promotion and co-marketing agreements and
     similar agreements relating to the intellectual property rights of the
     Company necessary for the conduct of the business of the Company as
     currently conducted, customer contracts for product sales and all bids or
     proposals for product or customer contracts not yet received, bid or
     awarded.

(cc) Labor and Employment Matters.  Except as set forth on Schedule 3.1(cc):
                                                           ----------------

(i)  The Company is not a party to or obligated to contribute to any employee
     benefit plan as defined in Section 3(3) of the Employee Retirement Income
     Security Act of 1974 ("ERISA") (an "Employee Benefit Plan"), guaranteed
     annual income plan, fund or arrangement, or any incentive, bonus, profit
     sharing, deferred compensation, stock option or purchase plan, agreement or
     arrangement, or any written or, to the knowledge of the Company, oral
     employment or consulting agreement (except employment offer letters), or
     any non-competition agreement, or any severance or written, or to the
     knowledge of Company, oral termination pay plans or policies, any
     hospitalization, disability or other insurance plans, or any other employee
     fringe benefit plans, or any collective bargaining agreement, or any other
     agreement, plan or arrangement similar to or in the nature of the
     foregoing, oral or written, whether or not an Employee Benefit Plan, except
     those set forth on Schedule 3.1(cc).  True, correct and complete copies of
                        ----------------                                       
     all of the written Employee Benefit Plans and other written plans and
     agreements and true, correct and complete written descriptions of all of
     such oral arrangements described in Schedule 3.1(cc) have heretofore been
                                         ----------------                     
     delivered by the Company to the Parent.  The Company does not have any
     unfunded liabilities on account of or in connection with any such Employee
     Benefit Plan, other plan, agreement or arrangement which is a non-
     multiemployer plan.

(ii) With respect to any non-multiemployer Employee Benefit Plan, (A) neither
     such Employee Benefit Plan nor any fiduciary has engaged in a prohibited
     transaction as defined in Section 406 of ERISA (for which no individual or
     class exemption exists under

                                       25
<PAGE>
 
     Section 408 of ERISA) or any prohibited transaction as defined in Section
     4975 of the Code (for which no individual or class exemption exists under
     Section 4975 of the Code), which may reasonably be expected to have a
     Material Adverse Effect on the Company; (B) all filings and reports as to
     such Employee Benefit Plan required to have been made on or before the date
     hereof to the IRS, to the United States Department of Labor or, if
     applicable, to the Pension Benefit Guaranty Corporation have been made on
     or before the date hereof (to the extent not granted a valid extension of
     the date of filing); (C) all disclosures to plan participants relating to
     such Employee Benefit Plan required by ERISA to have been made on or before
     the date hereof have been or will be duly made on or before that date; (D)
     there is no litigation, disputed claim (other than routine claims for
     benefits), governmental proceeding or investigation pending or threatened
     with respect to any such Employee Benefit Plan, its related trust or any
     fiduciary, administrator or sponsor of such Employee Benefit Plan; (E) each
     Employee Benefit Plan has been established, maintained, funded and
     administered materially in accordance with its governing documents and any
     applicable provisions of ERISA, the Code, other applicable law and all
     regulations and rulings promulgated thereunder; and (F) the Company has
     delivered to the Parent a true, correct and complete copy of (1) the most
     recent Form 5500 for each such Employee Benefit Plan filed with the IRS and
     the Department of Labor and, with respect to each Employee Benefit Plan
     which is an "employee pension benefit plan" within the meaning of Section
     3(2) of ERISA, the most recent determination letter received from the IRS,
     (2) each trust or custodial agreement and each deposit administration,
     group annuity, insurance or other funding contract associated with such
     Employee Benefit Plan, (3) the most recent financial information for each
     Employee Benefit Plan, (4) where applicable, the most recent actuarial
     report or valuation relating to each such Employee Benefit Plan which has
     been delivered to the Company by its actuaries, and (5) where applicable, a
     summary of any "reportable event" within the meaning of Section 4043(b) of
     ERISA.

(iii)The Company has never been a party to or obligated to contribute to any 
     multiemployer Employee Benefit Plan.

(iv) There has not been any (A) termination or partial termination of any
     Employee Pension Benefit Plan maintained by the Company (or by any Person
     which is or was under common control, within the meaning of Section 414(b),
     (c), (m) or (o) of the Code, with the Company (a "Section 414 Affiliate")
     during the period of such

                                       26
<PAGE>
 
     common control, at a time when Title IV of ERISA applied to such Plan, (B)
     commencement of any proceeding to terminate any such Plan pursuant to ERISA
     or otherwise, or (C) written notice given to the Company or any affiliate
     of the intention to commence or seek the commencement of any such
     proceeding, which (under (A)) resulted or (under (B) or (C)) would result
     in an insufficiency of plan assets necessary to satisfy benefit commitments
     under Title IV of ERISA or benefits vested under the Plan. Neither the
     Company nor any Section 414 Affiliate has incurred withdrawal liability,
     complete or partial, contingent or otherwise, under the Multiemployer
     Pension Plan Amendments Act of 1980.

(v)  The Company (A) is not a party to any collective bargaining agreement or
     discussions or negotiations with any Person or group looking toward any
     such agreement, (B) has not within the last three (3) years experienced any
     strike, lockout, work stoppage, slowdown, unfair labor practice claim or
     other labor difficulty (other than grievances and unfair labor practice
     claims in which the Company's only exposure was to monetary damages of
     $50,000 or less), and (C) to the knowledge of the Company, is not aware of
     a threatened strike, lockout, work stoppage, slowdown, unfair labor
     practice claim or other such labor difficulty.  The Company has no
     knowledge of any facts which would form the basis for the assertion of any
     grievance or unfair labor practice claim or other charge or complaint
     against the Company by or before the National Labor Relations Board or any
     state labor relations board or commission or representative thereof, and is
     not aware of any filing by any employee or employee group seeking
     recognition as a collective bargaining representative or unit.

(dd) Insider Contracts.  Except as set forth in the Company SEC Documents or on
     Schedule 3.1(dd) or as set forth and identified as such on any other
     ----------------
     Schedule hereto, there are no contracts, agreements, purchase orders,
     commitments, leases, understandings or arrangements, including loan
     arrangements, between the Company and any of its respective officers
     (except employment offer letters), directors or shareholders, or any
     related or affiliated Person, corporation or other entity (a true, correct
     and complete copy of each such written document and a true, correct and
     complete written description of each such oral relationship having
     heretofore been delivered by the Company to the Parent).

(ee) Other Material Contracts.  Schedule 3.1(ee) is a true, correct and 
                                ---------------
     complete list of all other (i.e., not identified on one or more of the
     foregoing Schedules hereto) material contracts, agreements, understandings
     and arrangements, oral and written, to which the Company is a party or by

                                       27
<PAGE>
 
     which the Company is bound. For purposes of this Section 3.1(ee),
     "material" shall mean containing an obligation (i) requiring, or reasonably
     anticipated to require, payment of more than $100,000 in any one (1) year
     period, or (ii) not terminable by or on the Company's behalf, without
     penalty, within ninety (90) days after the Closing, or (iii) terminable by
     or on behalf of the other party on ninety (90) days' notice or less, or
     (iv) having a term of more than twenty-four (24) months, or (v) of guaranty
     or suretyship, irrespective of the term or amount involved. True, correct
     and complete copies of such written material contracts have heretofore been
     delivered by the Company to the Parent. All material contracts are valid
     and binding, in full force and effect and enforceable in accordance with
     their terms, and there exists no default, and to the knowledge of the
     Company, no event has occurred which through notice or the passage of time
     or otherwise may result in a default, under the terms of any of the
     material contracts, except as set forth on Schedule 3.1(ee) and except
                                                ----------------
     where the invalidity, nonbinding nature, unenforceability, ineffectiveness
     or default would not have a Material Adverse Effect on the operations or
     financial condition of the Company taken as a whole.

(ff) Export of Products and Technologies.  To the knowledge of the Company, 
     there are no United States government restrictions prohibiting or, except
     for export licensing requirements which the Company has fulfilled or
     satisfied to date, otherwise affecting the Company in exporting its
     existing products and know-how to the foreign countries to which such are
     currently being exported (a description of all of such products and know-
     how and foreign countries being listed on Schedule 3.1(ff)).
                                               ----------------

(gg) Absence of Illegal Payments.  The Company has not authorized any of its 
     officers, directors, employees or non-employee agents to make, and to the
     knowledge of the Company, no officer, director, employee or non-employee
     agent of the Company has authorized or made, any offer, payment or promise
     to pay any money, or offered, given or promised to give anything of value,
     to any domestic or foreign government official, political party or official
     thereof or any candidate for political office (domestic or foreign), or to
     any other Person, while knowing or having reason to know that all or a
     portion of such money or thing of value would be offered, given or
     promised, directly or indirectly, to any of such Person(s) for purposes of
     (A) influencing any act or decision of such entity or Person, including a
     decision to fail to perform his or her official functions, or (B) inducing
     such entity or Person to use his or her influence with a domestic or
     foreign government or instrumentality thereof to affect or influence any
     act or decision of such government or instrumentality in order to assist
     the Company in obtaining or retaining business for or with, or directing
     business to, any Person, which offer, payment or promise

                                       28
<PAGE>
 
     constitutes a violation by the Company of the Foreign Corrupt Practices Act
     of 1977, as amended.

(hh) Absence of Anti-Boycott Violations.  To the knowledge of the Company, the 
     Company has not violated or is not in violation of any statute, law,
     decree, order, rule or regulation of any governmental body of the United
     States which prohibits or regulates the boycotting of or refusal to deal
     with any Person or entity, including without limitation the Export
     Administration Amendments of 1977 (50 U.S.C. App. (S) 2401 et seq.), the
                                                                -------
     Ribicoff Amendments to the Tax Reform Act of 1976 (Internal Revenue Code
     (S) 999) or the Sherman Act (15 U.S.C. (S) l et seq.), or any rule or
                                                  -------
     regulation promulgated pursuant thereto.

(ii) Environmental Matters.

(i)  Except as disclosed in Schedule 3.1(ii):  (A) the Company is currently in
                            ----------------                                  
     compliance with all applicable Environmental Laws, and has obtained all
     permits and other authorizations needed to operate its facilities, except
     where failure to comply with applicable Environmental Laws or where failure
     to obtain such permits and other authorizations would not have a Material
     Adverse Effect on the Company; (B) the Company has not violated any
     applicable Environmental Law, except where such violation would not have a
     Material Adverse Effect; (C) there are no present requirements of any
     applicable Environmental Laws which will increase materially the Company's
     costs of complying with the Environmental Laws nor to the Company's
     knowledge are any such requirements currently threatened to be imposed; (D)
     all past on-site generation, treatment, storage, disposal and other
     management of Regulated Substances by the Company and, to the knowledge of
     Company, by any prior owner, operator or occupant of any property presently
     or previously owned, leased or occupied by the Company was, when done, in
     compliance with then applicable Environmental Laws, except where failure of
     compliance would not have a Material Adverse Effect on the Company; (E) no
     past on-site generation, treatment, storage, disposal or other management
     of Regulated Substances:  (1) has resulted in the presence of Regulated
     Substances on, in, under or migrating from any property of the Company in
     violation of applicable Environmental Laws, except where such violation
     would not have a Material Adverse Effect on the Company; or (2) requires
     the investigation, cleanup, removal or remediation of any Regulated
     Substances, in order to comply with Environmental Laws, except where such
     investigation, cleanup, removal or remediation would not have a Material
     Adverse Effect on the Company; (F) all past

                                       29
<PAGE>
 
     off-site transportation, treatment, storage, disposal and other management
     of Regulated Substances generated by the Company was, when done, in
     compliance with then applicable Environmental Laws, except where failure of
     compliance would not have a Material Adverse Effect on the Company; (G) the
     Company did not, directly or indirectly, arrange for the treatment, storage
     or disposal of any Regulated Substances at any property or facility
     identified or, to the knowledge of the Company, is proposed to be
     identified on any list of contaminated properties or other properties which
     pursuant to Environmental Laws are the subject of an investigation or
     remediation action by any federal, state or, to the knowledge of the
     Company, local, government agency or instrumentality; (H) no property
     currently owned, leased or otherwise occupied by the Company and no
     property previously owned, leased or otherwise occupied by the Company is
     identified, or to the knowledge of the Company is proposed to be
     identified, on any list of contaminated properties or other properties
     which pursuant to Environmental Laws are the subject of an investigation or
     remediation action by any federal, state or, to the knowledge of the
     Company, local government agency or instrumentality; (I) the Company has
     not received any notice of any kind that the Company is or may be
     considered a party with potential responsibility under Environmental Laws
     for the costs of responding to a release or threatened release of any
     Regulated Substance which has not been resolved; (J) the Company has not
     filed or failed to file any notice required under any applicable
     Environmental Law reporting a release of any Regulated Substance; (K) no
     environmental lien and no unrecorded environmental lien has attached to any
     property of the Company, nor, to the knowledge of the Company, is there a
     reasonable basis to believe that such a lien may be attached to any
     property of the Company; and (L) during the period when the Company
     occupied any property now or formerly owned, leased or operated by the
     Company or, to the knowledge of the Company, during any period prior to its
     ownership, occupation or operation of such property: (1) there were no
     underground storage tanks or surface impoundments, (2) there was no
     asbestos-containing material in friable form, and (3) there were no
     polychlorinated biphenyls ("PCBs") other than those used, maintained or
     disposed of in compliance with all applicable Environmental Laws.

(ii) As used in this Section 3.1(ii), the following terms shall be defined as
     follows:  (A) "Environmental Laws" include but are not limited to any
     federal, state, local or foreign laws (including the common law), statutes,
     charters, ordinances, codes, rules or regulations,

                                       30
<PAGE>
 
     permits or permit conditions, licenses or authorizations, consent or
     administrative orders, agreements or understandings (whether previously
     existing, now existing or hereafter enacted, promulgated, issued or entered
     into) which pertain to the protection of human health or the environment or
     worker safety, including, without limitation, the Comprehensive
     Environmental Response, Compensation and Liability Act, 42 U.S.C. (S) 9601
     et seq.; the Resource Conservation and Recovery Act, 42 U.S.C. (S) 6901
     -- ----              
     et seq.;  the Hazardous Materials Transportation Act, 49 U.S.C. (S) 1801
     -- ----                
     et seq.; the Toxic Substance Control Act, 15 U.S.C. (S) 2601 et seq.; the 
     -- ----                                                      -- ---
     Federal Water Pollution Control Act, 33 U.S.C. (S) 1251 et seq.; the 
                                                             -- ----
     Federal Safe Drinking Water Act, 42 U.S.C. (S)(S) 300f-300j; the Federal 
     Air Pollution Control Act, 42 U.S.C. (S) 7401 et seq.; the Oil Pollution 
                                                   -- ---- 
     Act, 33 U.S.C. (S) 2701 et seq.; the Federal Insecticide, Fungicide and 
                             -- ---- 
     Rotenticide Act, 7 U.S.C. (S)(S) 136-136y; and the Occupational Safety 
     and Health Act, 29 U.S.C. (S) 651 et seq., as each may be amended from 
                                       -- ----                        
     time to time, regulations promulgated under the foregoing or any equivalent
     state statutes and regulation, and any judicial or administrative
     interpretation of such laws, statutes, charters, ordinances, codes, rules
     or regulations, permits or permit conditions, consent or administrative
     orders, agreements or understandings, including, without limitation, any
     judicial or administrative orders or judgments; and (B) "Regulated
     Substance" includes any substance the manufacturing, processing, sale,
     generation, treatment, storage, disposal, transportation, labeling,
     removal, remediation or other management of which is regulated by any
     applicable Environmental Law.

(jj) No Adverse Actions.  There is no existing, pending or, to the
knowledge of the Company, threatened termination, cancellation, limitation,
modification or change in the business relationship of the Company with any
supplier, customer or other Person or entity, except such actions which would
not have a Material Adverse Effect on the Company.

3.2         Representations, Warranties and Agreements of the Parent.
            -------------------------------------------------------- 
          The Parent represents and warrants to the Company as follows:

(a)  Organization, Standing and Power.  The Parent is a corporation
duly organized, validly existing and in good standing under the laws of the
Commonwealth of Pennsylvania with all requisite corporate power and authority to
own, operate and lease its properties, to carry on its business as now being
conducted and to enter into this Agreement and perform its obligations
hereunder.  Each Subsidiary of the Parent is duly organized,

                                       31
<PAGE>
 
validly existing and in good standing under the laws of the jurisdiction in
which it is organized and has the requisite corporate power and authority to
carry on its business as now being conducted, except where the failure to be so
organized, existing or in good standing or to have such power or authority would
not, individually or in the aggregate, have a Material Adverse Effect on the
Parent. The Parent and each of its Subsidiaries are duly qualified to do
business, and are in good standing, in each jurisdiction where the character of
their properties owned or held under lease or the nature of their activities
makes such qualification necessary, except where the failure to be so qualified
would not, individually or in the aggregate, have a Material Adverse Effect on
the Parent. For purposes of this Agreement, a "Subsidiary" of the Parent means
any corporation, partnership, limited liability company, joint venture or other
legal entity of which the Parent (either alone or through or together with any
other Subsidiary) owns, directly or indirectly, 50% or more of the stock or
other equity interests the holders of which are generally entitled to vote for
the election of the board of directors or other governing body of such
corporation, partnership, limited liability company, joint venture or other
legal entity.

(b)    Capital Structure.

(i)  The Parent.  As of the date hereof, the authorized capital stock of the
     Parent consists of 300,000,000 shares of Parent Common Stock, par value
     $.50 per share, and 5,000,000 shares of preferred stock, par value $.50 per
     share ("Parent Preferred Stock").  At the close of business on May 29,
     1998, (A) 122,341,004 shares of Parent Common Stock were issued and
     outstanding, all of which were validly issued, fully paid and
     nonassessable, and free of preemptive rights, (B) 850,328 shares of Parent
     Common Stock were held in the treasury of the Parent, and (C) 12,576,826
     shares of Parent Common Stock were reserved for future issuance pursuant to
     stock option arrangements of the Parent (collectively, the "Parent Stock
     Option Plans"), of which 3,512,826 shares were reserved for future issuance
     under stock options granted as of May 29, 1998.  The Parent Stock Option
     Plans are the only benefit plans of the Parent or its Subsidiaries under
     which any securities of the Parent or any of its Subsidiaries are issuable.
     No shares of Parent Preferred Stock are outstanding.  As of the date of
     this Agreement, except as set forth above, no shares of capital stock or
     other voting securities of the Parent were issued, reserved for issuance or
     outstanding.  As of the date of this Agreement, except for stock options
     covering not in excess of 3,512,826 shares of Parent Common Stock issued
     under the Parent Stock Option Plans (collectively, the "Parent Stock
     Options"), there are no options,

                                       32
<PAGE>
 
     warrants, calls, rights or agreements to which the Parent or any of its
     Subsidiaries is a party or by which any of them is bound obligating the
     Parent or any of its Subsidiaries to issue, deliver or sell, or cause to be
     issued, delivered or sold, additional shares of capital stock of the Parent
     or any of its Subsidiaries or obligating the Parent or any of its
     Subsidiaries to grant, extend or enter into any such option, warrant, call,
     right or agreement. Each outstanding share of capital stock of each
     Subsidiary of the Parent that is a corporation is duly authorized, validly
     issued, fully paid and nonassessable, and each such share is owned by the
     Parent or another Subsidiary of the Parent free and clear of all security
     interests, liens, claims, pledges, options, rights of first refusal,
     agreements, limitations on voting rights, charges and other encumbrances of
     any nature whatsoever. The Parent does not have any outstanding bonds,
     debentures, notes or other obligations the holders of which have the right
     to vote (or convertible into or exercisable for securities having the right
     to vote) with the stockholders of the Parent on any matter.

(ii) The Merger Subsidiary.  The Merger Subsidiary has, as of the date hereof,
     authorized capital stock consisting of 1,000 shares of Subsidiary Common
     Stock, of which 1,000 shares are issued and outstanding and owned by the
     Parent.  The Merger Subsidiary is a corporation duly organized, validly
     existing and in good standing under the laws of the State of Delaware.  All
     of the issued and outstanding shares of the Merger Subsidiary have been
     validly issued, are fully paid and nonassessable and are free of preemptive
     rights.  There are no outstanding rights, options, warrants, conversion
     rights or agreements for the purchase or acquisition from, or the sale or
     issuance by, the Merger Subsidiary of any shares of its capital stock,
     other than this Agreement.  Since its organization, the Merger Subsidiary
     has conducted no business activities, except such as are related to this
     Agreement and the performance of its obligations hereunder.

(c)  Authority.  On or prior to the date of this Agreement, the Board of
Directors of the Parent has declared the Merger advisable and fair to and in the
best interest of the Parent and its shareholders. The Parent has all requisite
corporate power and authority to enter into this Agreement and the Company
Option Agreement, to consummate the transactions contemplated by the Company
Option Agreement and to consummate the transactions contemplated hereby. The
execution and delivery of this Agreement and the Company Option Agreement by the
Parent and the consummation by the Parent of the transactions contemplated
hereby and thereby have been duly authorized by all necessary corporate action
on the

                                       33
<PAGE>
 
part of the Parent, subject, in the case of this Agreement, to the filing
of a Certificate of Merger as required by the DGCL. This Agreement and the
Company Option Agreement have been duly executed and delivered by the Parent and
(assuming the valid authorization, execution and delivery of this Agreement and
the Company Option Agreement by the Company and the validity and binding effect
of this Agreement and the Company Option Agreement on the Company) constitute
the valid and binding obligation of the Parent enforceable against the Parent in
accordance with their respective terms, except to the extent that enforceability
thereof may be limited by applicable bankruptcy, insolvency, reorganization or
other similar laws affecting the enforcement of creditors' rights generally and
by principles of equity regarding the availability of remedies. The issuance of
shares of Parent Common Stock to be issued in the Merger and the filing of a
registration statement on Form S-4 with the SEC by the Parent under the
Securities Act for the purpose of registering the shares of Parent Common Stock
to be issued in the Merger (together with any amendments or supplements thereto,
whether prior to or after the effective date thereof, the "Registration
Statement") have been duly authorized by the Parent's Board of Directors.

(d)  Consents and Approvals; No Violation.  Assuming that all consents, 
approvals, authorizations and other actions described in this Section 3.2(d)
have been obtained and all filings and obligations described in this Section
3.2(d) have been made, the execution and delivery of this Agreement and the
Company Option Agreement do not, and the consummation of the transactions
contemplated hereby and thereby and compliance with the provisions hereof and
thereof will not, result in any violation of, or default (with or without notice
or lapse of time, or both) under, or give to others a right of termination,
cancellation or acceleration of any obligation or the loss of a material benefit
under, or result in the creation of any lien, security interest, charge or
encumbrance upon any of the properties or assets of the Parent or any of its
Subsidiaries under, any provision of (i) the Articles of Incorporation or Bylaws
of the Parent, (ii) any provision of the comparable charter or organization
documents of any of the Parent's Subsidiaries, (iii) any loan or credit
agreement, note, bond, mortgage, indenture, lease or other agreement,
instrument, permit, concession, franchise or license applicable to the Parent or
any of its Subsidiaries, or (iv) any judgment, order, decree, statute, law,
ordinance, rule or regulation applicable to the Parent or any of its
Subsidiaries or any of their respective properties or assets, other than, in the
case of clauses (ii), (iii) or (iv), any such violations, defaults, rights,
liens, security interests, charges or encumbrances that, individually or in the
aggregate, would not have a Material Adverse Effect on the Parent, materially
impair the ability of the Parent to perform its obligations hereunder or under
the Company Option Agreement or prevent the consummation of any of the

                                       34
<PAGE>
 
transactions contemplated hereby or thereby. No filing or registration with, or
authorization, consent or approval of, any Governmental Entity is required by or
with respect to the Parent or any of its Subsidiaries in connection with the
execution and delivery of this Agreement or the Company Option Agreement by the
Parent or is necessary for the consummation of the Merger and the other
transactions contemplated by this Agreement or the Company Option Agreement,
except for (i) in connection, or in compliance, with the provisions of the HSR
Act, the Securities Act and the Exchange Act, (ii) the filing of the Certificate
of Merger with the Secretary of State of the State of Delaware, (iii) applicable
requirements, if any, of state securities or "blue sky" laws and the NYSE, (iv)
approval for listing the Parent Common Stock to be issued in the Merger on the
NYSE, and (v) such other consents, orders, authorizations, registrations,
declarations and filings the failure of which to be obtained or made would not,
individually or in the aggregate, have a Material Adverse Effect on the Parent,
materially impair the ability of the Parent to perform its obligations hereunder
or under the Company Option Agreement or prevent the consummation of any of the
transactions contemplated hereby or thereby.


(e) SEC Documents and Other Reports. The Parent has filed all required documents
with the SEC since January 1, 1995 (the "Parent SEC Documents"). As of their
respective dates, the Parent SEC Documents complied in all material respects
with the requirements of the Securities Act or the Exchange Act, as the case may
be, and, at the respective times they were filed, none of the Parent SEC
Documents contained any untrue statement of a material fact or omitted to state
a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading. The consolidated financial statements (including, in each case,
any notes thereto) of the Parent included in the Parent SEC Documents (the
"Parent Financial Statements") complied as to form in all material respects with
applicable accounting requirements and the published rules and regulations of
the SEC with respect thereto, were prepared in accordance with generally
accepted accounting principles (except, in the case of the unaudited statements,
as permitted by Form 10-Q of the SEC) applied on a consistent basis during the
periods involved (except as may be indicated therein or in the notes thereto)
and fairly presented in all material respects the consolidated financial
position of the Parent and its consolidated Subsidiaries as at the respective
dates thereof and the consolidated results of their operations and their
consolidated cash flows for the periods then ended. Except as disclosed in the
Parent SEC Documents or as required by generally accepted accounting principles,
the Parent has not, since March 31, 1998, made any change in the accounting
practices or policies applied in the preparation of the Parent Financial
Statements. Neither the

                                       35
<PAGE>
 
Parent nor any of its Subsidiaries had as of March 31, 1998 any liabilities or
obligations of any nature, whether or not accrued, contingent or otherwise, that
would be required by generally accepted accounting principles to be reflected on
the consolidated balance sheet of the Parent and its Subsidiaries (including the
notes thereto) included in the Financial Statements that are not so reflected.


(f)  Registration Statement and Prospectus/Proxy Statement.  None of
the information to be supplied by the Parent for inclusion or incorporation by
reference in the Registration Statement or the Prospectus/Proxy Statement will
(i) in the case of the Registration Statement, at the time it becomes effective,
contain any untrue statement of a material fact or omit to state any material
fact required to be stated therein or necessary in order to make the statements
therein not misleading or (ii) in the case of the Prospectus/Proxy Statement, at
the time of the mailing of the Prospectus/Proxy Statement, at the time of each
of the Stockholders Meeting and at the Effective Time, contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary in order to make the statements therein, in light of
the circumstances under which they are made, not misleading.  If at any time
prior to the Effective Time any event with respect to the Parent, its officers
and directors or any of its Subsidiaries shall occur which is required at that
time to be described in the Prospectus/Proxy Statement or the Registration
Statement, such event shall be so described, and an appropriate amendment or
supplement shall be promptly filed with the SEC and, as required by law,
disseminated to the stockholders of the Parent.  The Registration Statement will
comply (with respect to the Parent) as to form in all material respects with the
provisions of the Securities Act, and the Prospectus/Proxy Statement will comply
(with respect to the Parent) as to form in all material respects with the
provisions of the Exchange Act.

(g)  Absence of Certain Changes or Events.  Except as disclosed in the
Parent SEC Documents filed with the SEC prior to the date of this Agreement,
since March 31, 1998, there has been no event causing a Material Adverse Effect
on the Parent, or any development that would, individually or in the aggregate,
result in a Material Adverse Effect on the Parent.

(h)  Permits and Compliance. The Parent is in possession of all franchises, 
grants, authorizations, licenses, permits, easements, variances, exceptions,
consents, certificates, approvals and orders of any Governmental Entity
necessary for the Parent to own, lease and operate its properties or to carry on
its business as it is now being conducted (the "Parent Permits"), except where
the failure to have any of the Parent Permits would not, individually or in the
aggregate, have a Material Adverse Effect on the Parent, and, as of the date of
this Agreement, no suspension or cancellation of any of the

                                       36
<PAGE>
 
Parent Permits is pending or, to the knowledge of the Parent, threatened, except
where the suspension or cancellation of any of the Parent Permits would not,
individually or in the aggregate, have a Material Adverse Effect on the Parent.
Parent is not in violation of (i) its charter, by-laws or other organizational
documents, (ii) any applicable law, ordinance, administrative or governmental
rule or regulation, or (iii) any order, decree or judgment of any Governmental
Entity having jurisdiction over the Parent, except, in the case of clauses (i),
(ii) and (iii), for any violations that, individually or in the aggregate, would
not have a Material Adverse Effect on the Parent. As of the date hereof, there
is no contract or agreement, not entered into in the ordinary course of
business, that is material to the business, properties, assets, liabilities,
financial condition, results of operations or prospects of the Parent and its
Subsidiaries, taken as a whole. Except as set forth in the Parent SEC Documents
filed prior to the date of this Agreement, no event of default or event that,
but for the giving of notice or the lapse of time or both, would constitute an
event of default exists or, upon the consummation by the Parent of the
transactions contemplated by this Agreement or the Company Option Agreement,
will exist under any indenture, mortgage, loan agreement, note or other
agreement or instrument for borrowed money, any guarantee of any agreement or
instrument for borrowed money or any lease, contractual license or other
agreement or instrument to which the Parent is a party or by which the Parent is
bound or to which any of the properties, assets or operations of the Parent is
subject, other than any defaults that, individually or in the aggregate, would
not have a Material Adverse Effect on the Parent.

(i)  Actions and Proceedings.  Except as set forth in the Parent SEC
Documents filed prior to the date of this Agreement, there are no outstanding
orders, judgments, injunctions, awards or decrees of any Governmental Entity
against or involving the Parent or any of its Subsidiaries, or against or
involving any of the present or, to the knowledge of the Parent, former
directors, officers, employees, consultants or agents of the Parent or any of
its Subsidiaries, in their capacities as such, any of its or their properties,
assets or business or employee benefit plan of the Parent that, individually or
in the aggregate, would have a Material Adverse Effect on the Parent or
materially impair the ability of the Parent to perform its obligations hereunder
or under the Company Option Agreement.  As of the date of this Agreement, there
are no actions, suits, labor disputes or claims or legal, administrative or
arbitrative proceedings or governmental investigations pending or, to the
knowledge of the Parent, threatened against or involving the Parent or any of
its Subsidiaries or any of its or their present or, to the knowledge of the
Parent, former directors, officers, employees, consultants, agents or
stockholders, in their capacities as such, or any of its or their properties,

                                       37
<PAGE>
 
assets or business or any employee benefit plan of the Parent that, individually
or in the aggregate, would have a Material Adverse Effect on the Parent or
materially impair the ability of the Parent to perform its obligations hereunder
or under the Company Option Agreement.  As of the date hereof, there are no
actions, suits, labor disputes or other litigation, legal or administrative
proceedings or governmental investigations pending or, to the knowledge of the
Parent, threatened against or affecting the Parent or any of its Subsidiaries or
any of its or their present or, to the knowledge of the Parent, former officers,
directors, employees, consultants, agents or stockholders, in their capacities
as such, or any of its or their properties, assets or business relating to the
transactions contemplated by this Agreement and the Company Option Agreement.
For purposes of this Agreement, the term "knowledge of the Parent" shall mean
the actual knowledge of the officers and directors of the Parent.

(j)  FDA Matters.  Neither the Parent nor any of its Subsidiaries (i)
is a party to any pending investigation or proceeding by or before the FDA or
any other duly authorized Drug Regulatory Agencies or any other duly authorized
governmental authority which regulates the sale of drugs and controlled
substances in any jurisdiction; (ii) has knowledge of any pending regulatory
action of any sort (other than non-material routine or periodic inspections or
reviews) against the Parent or any of its Subsidiaries by the FDA or any other
duly authorized Drug Regulatory Agencies or any other governmental authority
which regulates the sale of drugs and controlled substances in any jurisdiction
which could have a Material Adverse Effect on the Parent, or in any material way
limit or restrict the ability of the Parent or any of its Subsidiaries to market
existing products; (iii) has knowingly committed or permitted to exist any
violation of the rules and regulations of the FDA or any other duly authorized
Drug Regulatory Agencies or any other governmental authority which regulates the
sale of drugs and controlled substances in any jurisdiction which has not been
cured by the Parent or any of its Subsidiaries or waived by the FDA or any such
regulatory authority; (iv) has received notice from any third party (whether or
not in writing), or has knowledge of, any claim, dispute or controversy relating
to the supply of regulated materials used in the products of the Parent or any
of its Subsidiaries, or the quality, formulation, potency, toxicity or efficacy
of such materials; or (v) anticipates, or knows of any pending, threatened or
potential action by any duly authorized Drug Regulatory Agencies or any other
governmental authority which regulates the sale of drugs and controlled
substances in any jurisdiction which could have a Material Adverse Effect on the
Parent or in any material way limit or restrict the ability of the Parent or any
of its Subsidiaries to market existing products.  To the knowledge of the
Parent, it and each of its Subsidiaries have

                                       38
<PAGE>
 
fulfilled in all material respects all regulatory requirements necessary or
requisite to the continued marketing of their existing products.


(k)  Labor Relations.   To the knowledge of the Parent, the Parent has a
good relationship with its employees and has no reason to believe that there
will be any adverse change in any such relationship, whether as a result of the
consummation of the transactions provided for by this Agreement or otherwise.


(l)  Patents and Certain Other Intellectual Property Rights.

(i)  The Parent owns, or possesses the right to use, all of the necessary
     intellectual property rights to the conduct of the business of the Parent
     as presently conducted except for rights to which, if not so owned or
     possessed, would not individually or in the aggregate have a Material
     Adverse Effect on the Parent.  Such ownership or right to use, as the case
     may be, is free and clear of all liens, security interests, claims and
     rights to use of third parties except those which would not, individually
     or in the aggregate have a Material Adverse Effect on the Parent.

(ii) There are no material royalties, honoraria, fees or other payments,
     incurred outside the ordinary course of business, payable as of the date
     hereof by the Parent to any person by reason of the ownership, use,
     license, sale or disposition of any of the Parent's intellectual property
     rights.

(iii)The Parent is not, to the knowledge of the Parent, infringing the right of
     any other party with respect to any intellectual property rights which
     would, individually or in the aggregate, be reasonably likely to have a
     Material Adverse Effect on the Parent.

(m) Parent Common Stock. The shares of Parent Common Stock to be issued in
accordance with this Agreement will be, upon issuance, duly authorized, validly
issued, fully paid and nonassessable, with no personal liability attaching to
the ownership thereof. Such issuance of shares of Parent Common Stock will be
free of any restrictions on transfer imposed by the Parent, other than those
contemplated by this Agreement. There are no preemptive rights or other anti-
dilution rights which would become effective upon or prohibit such issuance of
shares of Parent Common Stock.

(n)  Opinion of Financial Advisor.  The Parent has received the written
opinion of SBC Warburg Dillon Read Inc. ("Dillon Read"), dated the date hereof,
to the effect that, as of the date hereof, the Exchange Ratio is fair to the

                                       39
<PAGE>
 
Parent from a financial point of view, a copy of which opinion has been
delivered to the Company.

(o)  Finders and Investment Bankers.  Except for Dillon Read, whose
fees will be paid by the Parent, there is no investment banker, broker, finder
or other intermediary which has been retained by or is authorized to act on
behalf of the Parent or the Merger Subsidiary who might be entitled to any fee
or commission in connection with the transactions contemplated by this
Agreement.

(p)  Parent Affiliate Agreements.  Schedule 3.2(p) contains a list
                                   ---------------                
(reasonably satisfactory to counsel for the Company) identifying those Persons
who may be deemed to be "affiliates" of the Parent on the date hereof, as that
term is used in paragraphs (c) and (d) of Rule 145 under the Securities Act (the
"Parent Affiliates").

3.3         Representations and Warranties as to the Merger Subsidiary.
            ---------------------------------------------------------- 
          The Parent and the Merger Subsidiary represent and warrant to the
          Company as follows:

(a)  Organization, Standing, Power and Capitalization of the Merger
Subsidiary.  The Merger Subsidiary is a corporation duly organized, validly
existing and in good standing under the laws of the state of Delaware with all
requisite corporate power and authority to carry on the business to be conducted
by it prior to the Effective Date and to enter into this Agreement and perform
its obligations hereunder.  The Merger Subsidiary is not, and is not required to
be, qualified to do business in any jurisdiction other than the state of
Delaware.  The Merger Subsidiary has duly authorized capital stock consisting of
1,000 shares of common stock, par value $.50 per share, all of which are issued
and outstanding and owned by the Parent.  All of such issued and outstanding
shares have been validly issued, are fully paid and nonassessable, and are free
of preemptive rights.  There are no outstanding rights, options, warrants,
conversion rights or agreements for the purchase or acquisition from, or the
sale or issuance by, the Merger Subsidiary of any shares of its capital stock
other than in connection with this Agreement.

(b)  Business of the Merger Subsidiary.  Since its organization, the
Merger Subsidiary has not engaged in any business activities, entered into any
transactions or incurred any liabilities whatsoever, except such as are related
to the transactions contemplated by this Agreement.  The Merger Subsidiary has
no subsidiaries.

(c)  Authorization; Binding Agreement.  Pursuant to its Certificate of
Incorporation, the Merger Subsidiary has requisite corporate power and

                                       40
<PAGE>
 
authority to execute and deliver this Agreement and to consummate the
transactions contemplated hereby. The execution and delivery of this Agreement
and the consummation of the transactions contemplated hereby, including but not
limited to the Merger, have been duly and validly authorized by the Parent as
sole stockholder of the Merger Subsidiary and by the Merger Subsidiary's Board
of Directors and no other corporate proceedings on the part of the Merger
Subsidiary are necessary to authorize the execution and delivery of this
Agreement or to consummate the transactions so contemplated. This Agreement has
been duly and validly authorized, executed and delivered by the Merger
Subsidiary and constitutes the legal, valid and binding agreement of the Merger
Subsidiary, enforceable against it in accordance with its terms, except to the
extent that enforceability thereof may be limited by applicable bankruptcy,
insolvency, reorganization or other similar laws affecting the enforcement of
creditors' rights generally and by principles of equity regarding the
availability of remedies.

(d)  Compliance With Other Instruments, Etc.  Neither the execution or
delivery of this Agreement nor the consummation of the transactions contemplated
hereby will conflict with, result in any violation of or constitute a default
under the Certificate of Incorporation or Bylaws of the Merger Subsidiary or any
judgment, decree, order or any material law or regulation by which the Merger
Subsidiary is bound or affected.

(e)  Governmental and Other Consents, Etc.  No consent, approval or
authorization of or designation, declaration or filing with any Governmental
Entity on the part of the Merger Subsidiary is required in connection with the
execution or delivery of this Agreement by the Merger Subsidiary or the Merger
Subsidiary's consummation of the transactions contemplated hereby other than (i)
filings in the State of Delaware in accordance with the DGCL and (ii) filings
under the HSR Act.

4.          COVENANTS.
            --------- 
4.1         Covenants of the Company.
            ------------------------ 
          The Company agrees that prior to the Effective Date:

(a)  Action in Furtherance of Merger.  Subject to the terms and
conditions herein provided, the Company agrees to use commercially reasonable
efforts to take, or cause to be taken, such action, and to do, or cause to be
done, such things as are necessary, proper or advisable to consummate and make
effective as promptly as practicable the Merger and the transactions
contemplated by this Agreement, including (i) the defending of any lawsuits or
other legal proceedings, whether judicial or administrative,

                                       41
<PAGE>
 
challenging this Agreement or the consummation of the transactions contemplated
hereby, (ii) obtaining all governmental consents required for the consummation
of the Merger and the transactions contemplated thereby, and (iii) making all
necessary filings under the HSR Act. Upon the terms and subject to the
conditions hereof, the Company agrees to use commercially reasonable efforts to
take, or cause to be taken, such actions and to do, or cause to be done, such
things as are necessary to satisfy the other conditions of the Closing set forth
herein. The Company shall consult with counsel for the Parent as to, and shall
permit such counsel, at the Parent's expense, to participate in the decision-
making process as to the strategy to be employed in, any lawsuits or proceedings
referred to in clause (i) above brought against the Company, but not against the
Parent, provided that counsel for the Company shall retain control of any such
lawsuits or proceedings.

(b)  Maintenance of Properties.  The Company shall, and shall cause PL
to, maintain all of its and their respective properties in customary repair,
order and condition, reasonable wear and use and damage by fire or other
casualty excepted, and shall maintain, and shall cause PL to maintain, insurance
upon all of its and their properties and with respect to the conduct of its and
their businesses in amounts and kinds comparable to that in effect on the date
of this Agreement.

(c)  Access and Information.  Between the date of this Agreement and
the Effective Date, upon reasonable notice, the Company and PL shall give the
Parent and its authorized representatives (including its financial advisors,
accountants and legal counsel) access, at all reasonable times and in a manner
which shall not cause unreasonable disturbance, to all plants, offices,
warehouses and other facilities and to all contracts, agreements, commitments,
books and records (including Tax Returns) of the Company and PL (except to the
extent any such agreements or contracts by their terms restrict access to third
parties and the consent of the other party(ies) thereto cannot be obtained after
commercially reasonable efforts to do so), shall permit the Parent to make such
inspections as it may reasonably require and shall cause its officers and those
of PL promptly to furnish the Parent with such financial and operating data and
other information with respect to the business and properties of the Company and
PL, as may from time to time be reasonably requested.  All data and information
so received from the Company shall be deemed received pursuant to the
Confidentiality Agreement, and the Parent shall cause its officers, directors,
employees, auditors, counsel, financial advisors and agents to comply with the
provisions of the Confidentiality Agreement with respect to such data and
information.

                                       42
<PAGE>
 
(d)  Conduct of Business.  Except as expressly contemplated by this
Agreement or as otherwise agreed in writing by the Parent, during the period
from the date of this Agreement through the Effective Time, the Company shall,
and the Company shall cause PL to, conduct its business in the ordinary course
consistent with past practice, and the Company shall, and the Company shall
cause PL to, use commercially reasonable efforts to (i) preserve intact its
business organization, (ii) keep available the services of its officers and
employees, (iii) preserve its relationships with customers and suppliers, and
(iv) maintain satisfactory relationships with all other Persons with which it
does business.  Without limiting the generality of the foregoing, and except as
otherwise expressly provided in this Agreement or otherwise agreed to in writing
by the Parent, prior to the Effective Time, neither the Company nor PL shall,
without the prior written consent of the Parent:

(i)  amend or propose to amend its Certificate of Incorporation or Bylaws;

(ii) other than in the ordinary course of business consistent with past
     practice:  (A) create, incur or assume any indebtedness for borrowed money
     or obligations in respect of capital leases; (B) assume, guarantee, endorse
     or otherwise become liable or responsible (whether directly, indirectly,
     contingently or otherwise) for the obligations of any other Person except
     the Company or PL; (C) make any loans, advances or capital contributions
     to, or investments in, any other Person (other than customary travel or
     business advances to employees  made in the ordinary course of business
     consistent with past practice); (D) make any capital expenditure or
     expenditures which, individually, is in excess of $10,000 or, in the
     aggregate, are in excess of $50,000; (E) enter into or amend any agreement
     or contract material to the Company; or (F) incur any material liability or
     obligation (absolute, accrued, contingent or otherwise);

(iii)sell, transfer, lease, license or otherwise dispose of, or mortgage
     or encumber, or agree to sell, transfer, lease, license or otherwise
     dispose of, or mortgage or encumber, any assets or properties, real,
     personal, intangible or mixed, other than the sale, transfer or disposition
     of the Company's products in the ordinary course of business;

(iv) in the case of the Company, except as expressly provided in this Agreement,
     amend or terminate the Company Rights Plan prior to the earlier of the
     Effective Time or the termination of this

                                       43
<PAGE>
 
     Agreement, unless required to do so by a court of competent jurisdiction;

(v)  in the case of the Company, deliver any "put notices" under the Common
     Stock Investment Agreement or issue any shares of Company Common Stock
     pursuant thereto; or

(vi) authorize, recommend, propose or announce an intention to do any of the
     foregoing, or enter into any contract, agreement, commitment or arrangement
     to do any of the foregoing.

(e)  Capital Stock.  Between the date hereof and the Effective Time,
except as specifically contemplated by this Agreement or the Company Option
Agreement, neither the Company nor PL shall, unless otherwise agreed to in
writing by Parent, (i) make any changes in its authorized capital stock; (ii)
authorize or issue any securities convertible into, or exchangeable with, the
capital stock of the Company or PL; (iii) issue any stock options, warrants or
other rights calling for the issue, transfer, sale or delivery of its capital
stock or other securities except pursuant to the Company Stock Option Plans, the
Company Employee Stock Purchase Plan or the Company 401(k) Plan consistent with
past practice; provided, however, the Company shall not issue any "performance
share awards" and "stock purchase rights" under the Equity Incentive Plan of the
Company; (iv) declare or pay any stock dividend or effect any recapitalization,
split-up, combination, exchange of shares or other reclassification in respect
of its outstanding shares of capital stock; (v) issue, transfer, sell or deliver
any shares of its capital stock, except Company Common Stock to be issued:  (A)
upon the exercise of stock options previously granted pursuant to existing
Company Stock Option Plans or granted in accordance with this Section 4.1(e),
(B) pursuant to the exercise of the Company Warrant, or (C) as required by the
terms of the Company Employee Stock Purchase Plan or the Company 401(k) Plan;
(vi) purchase, redeem or otherwise acquire any outstanding shares of its capital
stock or any other securities of the Company or any rights, warrants or options
to acquire any such shares or securities; or (vii) declare, pay or set apart for
payment any dividends on, or make any other actual, constructive or deemed
distributions in respect of its capital stock or otherwise make any payments to
its stockholders in their capacity as such.  Except in a manner consistent with
past practice, no award or grant under the Company Stock Option Plans or any
other benefit plan or program shall be made without the consent of the Parent.
Except as specifically contemplated by this Agreement, the Company shall not
make any material amendment to any of (i) the Company Stock Option Plans or
options outstanding thereunder, or (ii) any other option or warrant agreement,
including, without limitation, the Company Warrant.

                                       44
<PAGE>
 
(f)  No Solicitation.

(i)  The Company shall cease, and shall cause PL to cease and shall use
     commercially reasonable efforts to cause its and PL's respective officers,
     directors, employees, counsel, investment bankers, financial advisers,
     accountants, other representatives and agents (collectively, the "Company
     Representatives") to cease, in each case immediately after the date hereof,
     any discussions or negotiations with any parties that may be ongoing with
     respect to a Takeover Proposal.  Neither the Company nor the Board of
     Directors of the Company shall, nor shall either of them authorize or
     permit PL or any Company Representative to:  (A) solicit, initiate or
     encourage (including by way of furnishing information), or take any other
     action to facilitate, any inquiries or the making of any proposal which
     constitutes, or may reasonably be expected to lead to, any Takeover
     Proposal; (B) participate in any discussion or negotiations regarding any
     Takeover Proposal; (C) approve or agree to or endorse any Takeover
     Proposal; (D) enter into any agreement with respect to any Takeover
     Proposal; or (E) other than as permitted by Section 4.1(m), withdraw or
     modify, or propose to withdraw or modify in a manner adverse to Parent, the
     approval or recommendation of this Agreement or the Merger; provided,
     however, that, notwithstanding any other provision hereof, the Company and
     the Board of Directors of the Company may, at any time prior to the time
     the stockholders of the Company shall have approved the Merger, engage in
     the actions prohibited by this Section 4.1(f)(i) in response to an
     unsolicited Takeover Proposal which did not result from a breach of this
     Section 4.1(f)(i) and subject to compliance with Section 4.1(f)(ii) if, and
     only to the extent that, (x) the Board of Directors of the Company
     determines in good faith, based upon the advice of its legal counsel as to
     legal matters, that it is necessary to do so in order to comply with its
     fiduciary duties to the Company's shareholders under applicable law, (y)
     the Board of Directors of the Company determines that the Takeover Proposal
     is a Superior Proposal, and (z) the party who submitted the Takeover
     Proposal executes a customary confidentiality agreement (as determined by
     the Company after receiving such Takeover Proposal and after consultation
     with its outside legal counsel), the benefits of the terms of which if more
     favorable to the other party than those contained in the confidentiality
     agreement in place with Parent, shall be extended to Parent,

(ii) In addition to the obligations of the Company set forth in Section
     4.1(f)(i), the Company shall promptly advise Parent orally and in

                                       45
<PAGE>
 
     writing of any Takeover Proposal received by Company or any request for
     information stated by the proponent to be in contemplation of any Takeover
     Proposal, or any inquiry which could reasonably be expected to lead to any
     Takeover Proposal, the material terms and conditions of such Takeover
     Proposal or request or inquiry and the identity of the Person making such
     Takeover Proposal, request or inquiry. The Company shall keep the Parent
     reasonably informed of any material amendment or modification to such
     Takeover Proposal, request or inquiry.


(iii) "Takeover Proposal" means any inquiry, proposal or offer from any
      Person relating to any: (A) tender or exchange offer, merger,
      consolidation or similar transaction involving the Company or PL, (B)
      sale, lease or other disposition directly or indirectly by merger,
      consolidation, or share exchange of assets of the Company or PL
      representing 10% or more of the consolidated assets of the Company or PL,
      (C) issuance, sale or other disposition of (including by way of merger,
      consolidation, share exchange or similar transaction) securities (or
      options, rights or warrants to purchase, or securities convertible into,
      such securities) representing 10% or more of the voting power of the
      Company, (D) transaction in which any Person shall acquire beneficial
      ownership (as such term is defined in Rule 13d-3 under the Exchange Act),
      or the right to acquire beneficial ownership or any "group" (as such term
      is defined under the Exchange Act) shall have been formed which
      beneficially owns or has the right to acquire beneficial ownership of 25%
      or more of the outstanding Common Stock, in each case, other than the
      transactions with Parent contemplated by this Agreement or the Company
      Option Agreement referred to in the recitals to this Agreement.

(iv) "Superior Proposal" means any Takeover Proposal on terms which the Board of
     Directors of the Company determines in its good-faith judgment, based in
     part on the advice of a financial advisor of nationally recognized
     reputation (which opinion shall be provided promptly to Parent), to be more
     favorable to the stockholders of the Company than the Merger from a
     financial point of view and for which financing is then committed or
     reasonably likely to be available.

(v)  For purposes of this Agreement, the term "Person" shall mean any
     individual, corporation, partnership, trust, unincorporated association,
     limited liability company, governmental agency or any other entity.

                                       46
<PAGE>
 
(g)  No Final Put Notice.  The Company shall refrain from delivering a
"final put notice" in respect of the "put notice" delivered under the Common
Stock Investment Agreement on June 4, 1998.

(h)  Compensation Matters.  Except with the prior written consent of
the Parent, neither the Company nor PL shall (i) pay, agree to pay or accelerate
the payment of any bonus, severance or other compensation to any officer or
employee not currently required under an existing agreement or employee benefit
plan or arrangement (and with respect to officers and directors, only to the
extent such agreement, plan or arrangement is described in the Company's 1998
Proxy Statement) except for increases in compensation of employees who are not
officers or directors of the Company consistent with past practices, (ii) make
payment of any bonus, severance or other compensation to any officer or employee
which is permitted hereunder in any property other than cash, (iii) create any
new employee benefit plan or arrangement, (iv) modify any existing employee
benefit plan, arrangement or agreement in any respect which would materially
increase the compensation payable thereunder to employees, or (v) enter into any
new employment agreement or modify any existing employment agreement of any
employee who is an officer or director of the Company or PL.

(i)  Contracts.  Except as otherwise agreed to in writing by the
Parent, neither the Company nor PL shall enter into, terminate or modify in any
material respect any contract, agreement or commitment material to the Company
without the prior written consent of the Parent, which consent shall not be
unreasonably withheld.

(j)  Tax Matters.  The Company and PL shall continue to file when due
all federal, state, local, foreign and other tax returns, reports and
declarations required to be filed by them, and shall pay or make full and
adequate provision for the payment of all taxes and governmental charges due or
payable by them.  Neither the Company nor PL shall prepare or file any Tax
Return inconsistent with past practice or, on any such Tax Return, take any
position, make any election, or adopt any method that is inconsistent with
positions taken, elections made or methods used in preparing or filing similar
Tax Returns in prior periods or make any tax election or settle or compromise
any material federal, state, local or foreign income tax liability.

(k)  Amendments to the Schedules.  The Company shall make such
amendments to the Schedules referred to in Section 3.1 as are necessary to
reflect therein the occurrence of events or transactions occurring after the
date hereof and shall deliver a copy of each such amendment to the Parent on the
same date as the date of the amendment.  The Company shall

                                       47
<PAGE>
 
deliver such additional amendments from time to time as are necessary to reflect
any material event occurring between the date hereof and the Effective Date.

(l)  Notification of Certain Matters.  The Company shall give prompt
notice to the Parent of:  (i) any notice of, or other communication relating to,
a default or event which, with notice or lapse of time or both, would become a
default under any agreement, indenture or instrument to which the Company or PL
is a party or is subject which default could reasonably be expected to have a
Material Adverse Effect on the Company; (ii) any notice or other communication
from any third party alleging that the consent of such third party is or may be
required in connection with the transactions contemplated by this Agreement
including the Merger; (iii) any notice or other communication from any
regulatory authority or national securities exchange in connection with the
transactions contemplated by this Agreement; (iv) any Material Adverse Change
suffered by the Company, or the occurrence of an event which would be reasonably
expected to have a Material Adverse Effect on the Company; and (v) any claims,
actions, proceedings or investigations commenced or threatened in writing
involving or affecting the Company or PL, or any of their respective property or
assets, or any employee, consultant, director or officer, in his or her capacity
as such, of the Company or PL, which, if pending on the date hereof, would have
been required to have been disclosed pursuant to this Agreement or which relates
to the consummation of the Merger.

(m)  Stockholder Approval.  The Company shall take all steps necessary
to duly call, give notice of, convene and hold, no later than thirty-five (35)
days after the Registration Statement has been declared effective by the SEC, a
special meeting of its stockholders in accordance with the DGCL to consider and
vote upon the adoption and approval of this Agreement and the Merger and the
transactions contemplated hereby (the "Stockholders Meeting").  The Company,
through its Board of Directors, shall adopt a recommendation to the stockholders
of the Company that they adopt and approve this Agreement, shall use
commercially reasonable efforts, consistent with its legal obligations, to
obtain any necessary approval by its stockholders of the transactions
contemplated hereby and shall not withdraw or modify such recommendation, except
as permitted by Section 4.1(f)(i) or on the basis of the occurrence of a
Material Adverse Change with respect to the Parent or the occurrence of an event
which has, or can reasonably be expected to have, a Material Adverse Effect on
the Parent and the Board of Directors of the Company determines in good faith,
based upon the advice of its counsel as to legal matters, that it is necessary
to do so in order to comply with its fiduciary duties to the Company's
stockholders under applicable law.  Without limiting the

                                       48
<PAGE>
 
generality of the foregoing, the Company agrees that its obligations pursuant to
the first sentence of this Section 4.1(m) shall not be affected by the
commencement, public proposal, public disclosure or communication to the Company
of a Takeover Proposal.

(n)  Financial Statements.  The Company, promptly after the preparation
thereof, shall send to the Parent any financial statements prepared by or on
behalf of it for periods subsequent to March 31, 1998 as to which the
representations and warranties regarding the Company Financial Statements set
forth in Section 3.1(e) shall apply.

(o)  Proxy Statement.  The Company shall deliver to the Parent the
final form of proxy statement which the Company intends to distribute to its
stockholders in connection with the adoption and approval of this Agreement and
the Merger.

(p)  Company Affiliates.  The Company shall deliver to the Parent an
updated Schedule 3.1(s) reflecting any change in the identity of the Company
        ---------------                                                     
Affiliates within five (5) days of the Company having knowledge of such change.
In the event additional Persons become Company Affiliates after the date hereof,
the Company shall use commercially reasonable efforts to cause each such Person
to deliver to the Parent a written agreement in substantially the form of
Exhibit C hereto with each such Person within ten (10) days after the Company
- ---------                                                                    
has knowledge that such Person has become a Company Affiliate.

(q)  Takeover Statutes.  If any "business combination," "fair price,"
"control share acquisition" or "moratorium" statute or other similar statute or
regulation or any state "blue sky" or securities law statute shall become
applicable to the transactions contemplated hereby, the Company and the Board of
Directors of the Company shall, to the extent consistent with applicable law,
grant such approvals and take such actions as are reasonably necessary so that
the transactions contemplated hereby and thereby may be consummated as promptly
as practicable on the terms contemplated hereby and otherwise act to minimize
the effects of such statute or regulations on the transactions contemplated
hereby.

(r)  Prohibited Transactions.  The Company shall not acquire or agree
to acquire by merging or consolidating with, or by purchasing a substantial
portion of the assets of or equity in, or by any other manner, any business or
any corporation, limited liability company, partnership, association or other
business organization or division thereof or otherwise acquire or agree to
acquire any assets, other than transactions that are in the ordinary course of
business consistent with past practice and not material to the Company and PL
taken as a whole.  The Company shall not alter (through

                                       49
<PAGE>
 
merger, liquidation, reorganization, restructuring or in any other fashion) the
corporate structure or ownership of the Company or PL.

(s)  Accounting Changes.  The Company shall not make any change to
accounting policies or procedures (other than actions required to be taken by
generally accepted accounting principles).

(t)  Compliance With Law.  The Company shall not knowingly violate or
knowingly fail to perform any obligation or duty imposed upon it or PL by any
applicable federal or state law or regulation, guideline or ordinance.

(u)  Company Affiliates Agreements.  The Company shall use commercially
reasonable efforts to cause each Company Affiliate to deliver to the Parent
within ten (10) days of the date hereof a written agreement in substantially the
form of Exhibit C hereto, executed by each such Person.
        ---------                                      

4.2         Covenants of the Parent.
            ----------------------- 
          The Parent agrees that prior to the Effective Date:

(a)  Action in Furtherance of Merger.  Subject to the terms and
conditions herein provided, the Parent agrees to use commercially reasonable
efforts to take, or cause to be taken, such actions, and to do, or cause to be
done, such things as are necessary, proper or advisable to consummate and make
effective as promptly as practicable the Merger and the transactions
contemplated by this Agreement, including (i) defending any lawsuits or other
legal proceedings, whether judicial or administrative, challenging this
Agreement or the consummation of the transactions contemplated hereby, (ii)
obtaining all governmental consents required for the consummation of the Merger
and the transactions contemplated thereby, (iii) making all necessary filings
under the HSR Act, (iv) filing the Registration Statement and causing the same
to become effective; and (v) to the extent that the shares of Company Common
Stock are not voted in accordance with the terms of the Voting Agreements,
voting the irrevocable proxies granted to the Parent in the Voting Agreements in
favor of approving this Agreement and the transactions contemplated hereby, all
on the terms and conditions provided for herein.  Upon the terms and subject to
the conditions hereof, the Parent agrees to use commercially reasonable efforts
to take, or cause to be taken, such actions and to do, or cause to be done, such
things as are necessary to satisfy the other conditions of the Closing set forth
herein.  The Parent shall consult with counsel for the Company as to, and shall
permit such counsel, at the Company's expense, to participate in the decision-
making process as to the strategy to be employed in any lawsuits or proceedings
referred to in clause (i) above (which shall not include any such lawsuits or
proceedings to the extent that they relate to the Registration Statement)
brought against

                                       50
<PAGE>
 
the Parent, but not against the Company, provided that counsel for the Parent
shall retain control of any such lawsuits or proceedings. In case at any time
after the Effective Date any further action is necessary or desirable to carry
out the purposes of this Agreement, the officers and directors of the Surviving
Corporation shall take such necessary action and the Parent shall cause them to
do so.


(b)  Maintenance of Properties.  The Parent shall, and shall cause each
of its Subsidiaries to, maintain all of its and their respective properties in
customary repair, order and condition, reasonable wear and use and damage by
fire or other casualty excepted, and shall maintain, and shall cause each of its
Subsidiaries to maintain, insurance upon all of its and their properties and
with respect to the conduct of its and their businesses in amounts and kinds
comparable to that in effect on the date of this Agreement.

(c)  Access and Information.  Between the date of this Agreement and
the Effective Date, upon reasonable notice, the Parent shall give the Company
and its authorized representatives (including its financial advisors,
accountants and legal counsel) access, at all reasonable times and in a manner
which shall not cause unreasonable disturbance, to officers and senior
executives of the Parent as well as to financial and operating data and other
information as may from time to time be reasonably requested by the Company.
All data and information so received from the Parent shall be deemed received
pursuant to the Reciprocal Confidentiality Agreement, and the Company shall
cause its officers, directors, employees, auditors, counsel, financial advisors
and agents to comply with the provisions of the Reciprocal Confidentiality
Agreement with respect to such data and information.
 
(d)  Listing Application.  The Parent shall use commercially reasonable
efforts to effect listing of the Parent Common Stock to be delivered in
accordance with this Agreement on the NYSE upon notice of issuance.

(e)  Public Filings.  The Parent shall promptly file all periodic
reports required to be filed with the SEC and provide the Company with a copy of
such reports promptly after such filing.

(f)  Registration Statement.  The Parent shall deliver to the Company
the final form of Registration Statement which the Parent intends to have
declared effective by the SEC.

(g)  Conduct of Business.  Except as expressly contemplated by this
Agreement, during the period from the date of this Agreement to the Effective
Date, the Parent shall, and the Parent shall cause each of its

                                       51
<PAGE>
 
Subsidiaries to, conduct its business in the ordinary course and consistent with
past practice.


4.3         Covenants as to the Merger Subsidiary.
            ------------------------------------- 
          The Parent and the Merger Subsidiary agree that prior to the Effective
          Date:

(a)  No Business.  The Merger Subsidiary shall not engage in any
business activities or enter into any transaction whatsoever, except such as are
related to this Agreement and the performance of its obligations hereunder.

(b)  Access.  Until the Effective Date or until the abandonment of the
Merger as permitted by this Agreement, the Merger Subsidiary shall give to the
Company and its representatives full access, during normal business hours and
upon reasonable notice, to all of its properties, books, contracts, documents
and records, and shall furnish to the Company such financial and other
information concerning the Merger Subsidiary as the Company and its
representatives may from time to time reasonably request.

(c)  Actions in Furtherance of Merger.  The Merger Subsidiary shall use
commercially reasonable efforts to obtain such consents and authorizations of
third parties, to make such filings, and to give such notices to third parties,
which may be necessary or reasonably required on the part of the Merger
Subsidiary in order to effect, or in connection with, the transactions
contemplated by this Agreement.

4.4         Covenants of the Company and the Parent.
            --------------------------------------- 

(a)  Registration Statement.  The Company shall cooperate with the
Parent in the preparation by the Parent of, and the Parent shall file, the
Registration Statement with the SEC and shall use commercially reasonable
efforts to cause it to become effective.  The Parent shall use commercially
reasonable efforts to qualify such securities, if required, under applicable
state securities laws and to cause the shares of Parent Common Stock which are
to be delivered pursuant to this Agreement to be listed on the NYSE.  The
Prospectus/Proxy Statement shall include the prospectus which forms a part of
the Registration Statement.  The obligations of the Company pursuant to this
Section 4.4 shall be limited to providing the information required by items 15
and 18 of Form S-4, and the expense of providing such information shall be borne
by the Company.

(b)  Tax-Free Reorganization Treatment.  Each of the Company and the
Parent shall use commercially reasonable efforts to cause the Merger to be
treated as a "reorganization" within the meaning of Section 368 of the Code.

                                       52
<PAGE>
 
5.          CONDITIONS TO CLOSING; ABANDONMENT AND TERMINATION.
            -------------------------------------------------- 
5.1         Conditions to Each Party's Obligation to Effect the Merger.
            ---------------------------------------------------------- 

          The respective obligations of each party to this Agreement to effect
          the Merger shall be subject to the satisfaction prior to the Effective
          Date of the following conditions, and the Company or the Parent shall
          (x) not be required to close the Merger if any of the following shall
          not be true or shall not have occurred and (y) have the right to
          abandon the Merger and terminate this Agreement if any of the
          following shall not be true or shall not have occurred, as the case
          may be, by 5:00 p.m., Eastern time, on November 30, 1998:

(a)  Company Stockholder Approval.  This Agreement and the Merger shall
have been approved and adopted by the affirmative vote of at least a majority of
the votes cast by holders of the Company Common Stock entitled to vote thereon.

(b)  Consents.  Except to the extent such consents are not required at
the Effective Date:  (i) the Company shall have received the consents or
exemptions, or made the filings, as the case may be, which are referred to in
Section 3.1(d); (ii) the Parent shall have received the consents or exemptions,
or made the filings, as the case may be, which are referred to in Section 3.2(d)
hereof; and (iii) all notification and report forms required to be filed on
behalf of the parties to this Agreement with the Federal Trade Commission and
the Department of Justice under the HSR Act and rules thereunder shall have been
filed, and the waiting period required to expire under the HSR Act and rules
thereunder, including any extension thereof, shall have expired or early
termination of the waiting period shall have been granted.

(c)  Effectiveness.  The Registration Statement shall have become
effective under the Securities Act and shall not be the subject of any stop
order or proceeding seeking a stop order.

(d)  Listing.  The Parent Common Stock to be issued in the Merger shall
have been approved for listing on the NYSE upon notice of issuance.

(e)  No Legal Restraints.  No temporary restraining order, preliminary
or permanent injunction or other order issued by a court of competent
jurisdiction or other legal restraint or prohibition preventing the consummation
of the Merger shall be in effect.

5.2         Conditions to the Company's Closing and Its Right to Abandon.
            ------------------------------------------------------------ 

          The Company shall (x) not be required to close the Merger if any of
          the following shall not be true or shall not have occurred or shall
          not have been waived in

                                       53
<PAGE>
 
          writing by the Company at the Closing and (y) have the right to
          abandon the Merger and terminate this Agreement if any of the
          following shall not be true or shall not have occurred, or shall not
          have been waived in writing by the Company, as the case may be, by
          5:00 p.m., Eastern time, on November 30, 1998:

(a)  No Material Adverse Effect.  No event or circumstance shall have
occurred which has, or is reasonably expected to have, a Material Adverse Effect
on the Parent, including, without limitation, any Material Adverse Effect caused
by any of the following:

(i)  The failure of the representations and warranties of the Parent and Merger
     Subsidiary herein contained to be true and correct in all respects on and
     as of the Effective Date with the same force and effect as though made on
     and as of the Effective Date except as affected by transactions
     specifically contemplated by this Agreement;

(ii) The failure of either the Parent or the Merger Subsidiary to have performed
     all its obligations and agreements and complied with all covenants
     contained in this Agreement to be performed and complied with by it on or
     prior to the Effective Date; and

(iii)The execution, delivery and performance by the Parent of this
     Agreement and the consummation of the Merger having, directly or
     indirectly, resulted in a breach of, constituted an event of default under
     or resulted in the acceleration of, with or without the giving of notice,
     lapse of time or both, an obligation under any agreement of the Parent.

(b)  No Material Adverse Change.  Between the date hereof and the
Effective Date, there shall have been no Material Adverse Change with respect to
the Parent.

(c)  Officer's Certificate.  The Company shall have received a
certificate of the Chairman of the Board, the President or any Vice-President of
each of the Parent and the Merger Subsidiary, dated the Effective Date,
certifying as to the absence of any of the matters mentioned in Sections 5.2(a)
and (b).

(d)  Tax Opinion.  The Company shall have received an opinion of Heller
Ehrman White & McAuliffe, in form and substance reasonably satisfactory to the
Company, dated the Effective Time, substantially to the effect that on the basis
of facts, representations and assumptions set forth in such opinion which are
consistent with the state of facts existing as of the Effective Time, for
federal income tax purposes:

                                       54
<PAGE>
 
(i)  the Merger shall constitute a "reorganization" within the meaning of
     Section 368(a) of the Code, and the Company, the Merger Subsidiary and the
     Parent shall each be a party to that reorganization within the meaning of
     Section 368(b) of the Code;

(ii) no gain or loss shall be recognized by the Parent, the Merger Subsidiary or
     the Company as a result of the Merger;

(iii)no gain or loss shall be recognized by stockholders of the Company
     who exchange their shares of Company Common Stock solely for shares of
     Parent Common Stock pursuant to the Merger, except to the extent of cash,
     if any, received in lieu of fractional shares of Parent Common Stock;

(iv) the aggregate tax basis of the shares of Parent Common Stock received in
     exchange for shares of Company Common Stock pursuant to the Merger
     (including any fractional share of Parent Common Stock deemed to have been
     received) shall be the same as the aggregate tax basis of such shares of
     Company Common Stock surrendered in exchange therefor;

(v)  the holding period for shares of Parent Common Stock received in exchange
     for shares of Company Common Stock pursuant to the Merger shall include the
     holder's holding period for such shares of Company Common Stock surrendered
     in exchange therefor, provided such shares of Company Common Stock were
     held as capital assets by the holder at the Effective Time; and

(vi) the receipt of cash in lieu of a fractional share of Parent Common Stock by
     a stockholder of the Company will be treated as if the fractional share
     were distributed as part of the exchange and then redeemed by the Parent,
     and the cash payment will be treated as having been received as a
     distribution in full payment in exchange for the fractional shares redeemed
     and taxed as provided in Section 302(a) of the Code.

In rendering such opinion, Heller Ehrman White & McAuliffe may rely as to
matters of fact upon the representations contained herein and may require and
rely upon representations from the Parent, the Company and others.

(e)  Tax Certificate.  The Parent shall have delivered to the Company a
certificate confirming the accuracy of the representations and warranties and
the performance of the covenants on the part of the Parent and the Merger
Subsidiary as set forth in Section 8.4(a) hereof.

                                       55
<PAGE>
 
5.3         Conditions to the Parent's and the Merger Subsidiary's Closing and
            ------------------------------------------------------------------
            Right of the Parent and the Merger Subsidiary to Abandon.
            -------------------------------------------------------- 

          The Parent and Merger Subsidiary shall (x) not be required to close
          the Merger if any of the following shall not be true or shall not have
          occurred or shall not have been waived in writing by the Parent at the
          Closing and (y) have the right to abandon the Merger and terminate
          this Agreement if any of the following shall not be true or shall not
          have occurred, or shall not have been waived in writing by the Parent,
          as the case may be, by 5:00 p.m., Eastern time, on November 30, 1998:

(a)  No Material Adverse Effect.  No event or circumstance shall have
occurred which has, or is reasonably expected to have, a Material Adverse Effect
on the Company, including, without limitation, any Material Adverse Effect
caused by any of the following:

(i)  The failure of the representations and warranties of the Company herein
     contained to be true and correct in all respects on and as of the Effective
     Date;

(ii) The failure of the Disclosure Schedules, as amended immediately prior to,
     but on the same day as, the Merger on the Effective Date for events or
     transactions occurring after the date of this Agreement, to be true and
     correct in all respects on and as of the Effective Date with the same force
     and effect as though made on and as of the Effective Date;

(iii)The disclosure by any amendment to the Disclosure Schedules of the
     existence of any adverse change in the business, assets, financial
     condition or the results of operation of the Company and PL, taken as a
     whole;

(iv) The failure of the Company to have performed all its obligations and
     agreements and complied with all covenants contained in this Agreement to
     be performed and complied with by it on or prior to the Effective Date; and

(v)  The execution, delivery and performance by the Company of this Agreement
     and the consummation of the Merger having, directly or indirectly, resulted
     in a breach of, constituted an event of default under or resulted in the
     acceleration of, with or without the giving of notice, lapse of time, or
     both, an obligation under any agreement of the Company.

                                       56
<PAGE>
 
(b)  No Material Adverse Change.  Between the date hereof and the
Effective Date, there shall have been no Material Adverse Change with respect to
the Company.

(c)  Officer's Certificate.  The Parent and the Merger Subsidiary shall
have received a certificate of the Chairman of the Board, the President or any
Vice-President of the Company, dated the Effective Date, certifying as to:

(i)  the absence of any of the matters mentioned in Sections 5.3(a) and (b);

(ii) the number of shares of Company Preferred Stock issued and outstanding;

(iii)the number of Outstanding Shares of Company Common Stock; and

(iv) the information relating to the Company supplied by the Company in writing
     specifically for inclusion in the Registration Statement.

(d)  Tax Opinion.  The Parent shall have received an opinion of
Buchanan Ingersoll Professional Corporation, in form and substance reasonably
satisfactory to the Parent, dated the Effective Date, substantially to the
effect that on the basis of facts, representations and assumptions set forth in
such opinion which are consistent with the state of facts existing as of the
Effective Time, for federal income tax purposes:

(i)  the Merger shall constitute a "reorganization" within the meaning of
     Section 368(a) of the Code, and the Company, the Merger Subsidiary and the
     Parent shall each be a party to that reorganization within the meaning of
     Section 368(b) of the Code;

(ii) no gain or loss shall be recognized by the Parent, the Merger Subsidiary or
     the Company as a result of the Merger;

(iii)no gain or loss shall be recognized by stockholders of the Company
     who exchange their shares of Company Common Stock solely for shares of
     Parent Common Stock pursuant to the Merger, except to the extent of cash,
     if any, received in lieu of fractional shares of Parent Common Stock;

(iv) the aggregate tax basis of the shares of Parent Common Stock received in
     exchange for shares of Company Common Stock pursuant to the Merger
     (including any fractional share of Parent Common Stock deemed to have been
     received) shall be the same

                                       57
<PAGE>
 
     as the aggregate tax basis of such shares of Company Common Stock
     surrendered in exchange therefor;

(v)  the holding period of the shares of Parent Common Stock received in
     exchange for shares of Company Common Stock pursuant to the Merger shall
     include the holder's holding period for such shares of Company Common Stock
     surrendered in exchange therefor, provided such shares of Company Common
     Stock were held as capital assets by the holder at the Effective Time; and

(vi) the receipt of cash in lieu of a fractional share of Parent Common Stock by
     a stockholder of the Company will be treated as if the fractional share
     were distributed as part of the exchange and then redeemed by the Parent,
     and the cash payment will be treated as having been received as a
     distribution in full payment in exchange for the fractional shares redeemed
     and taxed as provided in Section 302(a) of the Code.

In rendering such opinion, Buchanan Ingersoll Professional Corporation may rely
as to matters of fact upon the representations contained herein and may require
and rely upon representations from the Parent, the Company and others.


(e)  Tax Certificate.  The Company shall have delivered to the Parent a
certificate confirming the accuracy of the representations and warranties and
the performance of the covenants on the part of the Company and the Surviving
Corporation as set forth in Section 8.4(b) hereof.

(f)  Outstanding Shares of Preferred Stock.  No shares of the Company
Preferred Stock shall be issued or outstanding.

(g)  FIRPTA Statement.  The Company shall have delivered to the Parent
a statement that the interest in Company is not a United States real property
interest as contemplated by Section 1.1445-2(c)(3) of the regulations
promulgated under the Code.

6.          ADDITIONAL PROVISIONS FOR ABANDONMENT AND TERMINATION.
            ----------------------------------------------------- 
6.1         Provisions of Abandonment and Termination.
            ----------------------------------------- 

          In addition to the provisions of Article 5 hereof, the Merger may be
          abandoned and this Agreement may be terminated at any time on or
          before the Effective Time, whether before or after approval by the
          stockholders of the Company:

                                       58
<PAGE>
 
(a)  Mutual Agreement.  By mutual agreement of the Boards of Directors
of the Parent, the Merger Subsidiary and the Company pursuant to resolutions
adopted by such Boards, notwithstanding any prior adoption of this Agreement or
approval of the Merger by the respective stockholders of the Merger Subsidiary
or the Company;

(b)  Violation of Order.  By either the Parent or the Merger
Subsidiary, on the one hand, or the Company, on the other, if consummation of
the Merger would violate any preliminary injunction or restraining order or
final, nonappealable order, decree, injunction, restraining order or judgment of
any United States court or other tribunal of competent jurisdiction;

(c)  Other Transactions Involving the Company.  By the Parent if any of
the following shall have occurred:

(i)  Any Person (other than the Parent or any Subsidiary of the Parent) shall
     have commenced (as such term is defined in Rule 14d-2 under the Exchange
     Act), a tender offer or exchange offer to purchase any Company Common Stock
     or securities convertible into such shares such that, upon consummation of
     such offer, such Person would own or control 50% or more of the then
     outstanding Company Common Stock and the Board of Directors of the Company,
     within ten (10) Business Days after such tender or exchange offer shall
     have been so commenced, fails to recommend against acceptance of such
     tender or exchange offer by its stockholders;

(ii) The Company or PL shall have authorized, recommended, proposed or publicly
     announced an intention to authorize, recommend or propose, or entered into,
     an agreement with any Person (other than the Parent or any Subsidiary of
     the Parent) to (A) effect a merger, consolidation or similar transaction
     involving the Company or PL, (B) sell, lease or otherwise dispose of assets
     of the Company or PL representing 10% or more of the consolidated assets of
     the Company and PL, (C) issue, sell or otherwise dispose of (including by
     way of merger, consolidation, share exchange or any similar transaction)
     securities (or options, rights or warrants to purchase), or securities
     convertible into, such securities) representing 10% or more of the voting
     power of the Company, or (D) grant to such Person a license of any
     intellectual property of the Company other than licenses in the ordinary
     course of business relating to the sale of the Company's products;

(iii)Any Person (other than the Parent or any Subsidiary of the Parent)
     shall have acquired beneficial ownership (as such term is defined

                                       59
<PAGE>
 
     in Rule 13d-3 under the Exchange Act) or the right to acquire beneficial
     ownership of, or any "group" (as such term is defined under the Exchange
     Act) shall have been formed which beneficially owns or has the right to
     acquire beneficial ownership of, 25% or more of the then outstanding
     Company Common Stock; or

(iv) The Company's Board of Directors shall have withdrawn or modified in a
     manner adverse to the Parent the recommendation of the Company's Board of
     Directors that the stockholders approve this Agreement and the Merger (it
     being understood and agreed that any communication by the Company or its
     Board of Directors to the stockholders of the Company that the Company's
     Board of Directors had determined not to withdraw or modify such
     recommendation, in whole or in part, because such action would or might
     give rise to a right on the part of the Parent to terminate this Agreement
     and/or obligate the Company to pay the Termination Fee shall nevertheless
     be deemed an adverse modification of such recommendation for purposes of
     this Section 6.1(c)(iv)).

(d)  Superior Proposal.  By the Company, in connection with entering
into an agreement for a Superior Proposal as expressly permitted by Section
4.1(f), provided that:  (i) the Company has complied with all provisions
thereof; (ii) immediately following such termination the Company executes a
definitive agreement to consummate the Superior Proposal; (iii) prior to any
such termination:  (x) the Company shall have provided the Parent with four (4)
days' notice of the terms of the Superior Proposal, and (y) the Company shall
have, and shall have caused the Company Representatives to have, negotiated in
good faith, during such four (4) day period, with respect to any proposal made
by the Parent to adjust the terms and conditions of this Agreement as would
enable the Company, consistent with the fiduciary duties of its Board of
Directors, to proceed with the Merger; and (iv) the Company shall have paid the
Parent the Termination Fee.

(e)  By either the Parent or the Company if the Merger shall have not been
consummated on or before November 30, 1998 (the "Termination Date"); provided,
however, that the right to terminate this Agreement under this Section 6.1(e)
shall not be available to any party whose failure to fulfill any obligation
under this Agreement has been the cause of, or resulted in, the failure of the
Effective Time to occur on or before Termination Date.

(f)  By the Company ten (10) days after the Stockholders Meeting (including any
adjournment thereof) if at the Stockholders Meeting (including any adjournment
thereof) this Agreement and the Merger shall fail to be

                                       60
<PAGE>
 
approved and adopted by the affirmative vote of the stockholders of the Company
as required under DGCL.

6.2         Termination of Agreement.
            ------------------------ 

          Subject to the provisions of Section 6.1(e), the Merger shall be
          abandoned and this Agreement shall be automatically terminated on the
          Termination Date, or such later date as the Board of Directors of the
          Parent, the Merger Subsidiary and the Company may mutually agree
          pursuant to resolutions adopted by such Boards.

6.3         Effect of Abandonment or Termination.
            ------------------------------------ 

          In the event of termination of this Agreement by either the Parent or
          the Company, as provided in Section 6.1, Section 6.2 or in Article 5
          of this Agreement, this Agreement shall forthwith become void and of
          no further force and effect; provided, however, that:  (a) each of the
          parties shall be entitled to pursue, exercise and enforce any and all
          remedies, rights, powers and privileges available to it at law or in
          equity for any breach of this Agreement ("Remedies") which occurred
          prior to such termination, which, in the case of the Parent, shall be
          in addition to its rights under Section 7.1(b); and (b) Sections
          3.1(d), 3.1(o) and 4.1(a) (insofar as such representations and
          warranties relate to the Company Option Agreement and the transactions
          contemplated thereby), Section 4.1(c), Section 4.2(c), Article 7,
          Section 8.7, Section 8.9, Section 8.10, Section 8.11 and Section 8.12
          shall survive the termination of this Agreement.

7.          EXPENSES.
            -------- 
7.1         Costs and Expenses.
            ------------------ 

(a)  Payment of Own Expenses.  Except as set forth in Section 7.1(b),
whether or not the Merger is consummated, all costs and expenses incurred in
connection with this Agreement and the transactions contemplated hereby shall be
paid by the party incurring such expense, and in connection therewith, each of
the Parent and the Company shall pay, with its own funds, any and all property
or transfer taxes imposed on such party, except that expenses incurred in
connection with printing and mailing the Prospectus/Proxy Statement to the
holders of Company Common Stock shall be shared equally by the Parent and the
Company and that the expenses incurred by either the Parent or the Company
pursuant to the Company Option Agreement shall be borne as provided therein.

(b)  Termination Fee.

(i)  If this Agreement is terminated by the Parent pursuant to Section 6.1(c)(i)
     or (iii) or, at the time of the termination of this

                                       61
<PAGE>
 
     Agreement, the Parent had the right to so terminate, and within 12 months
     after such termination the Company executes a definitive agreement to
     implement a Takeover Proposal (whether or not such Takeover Proposal
     triggered the termination right), then the Company shall pay to the Parent
     Termination Fee in an amount equal to $9 million (the "Termination Fee")
     within two (2) Business Days after the execution of such definitive
     agreement.

(ii) If this Agreement is terminated by the Parent pursuant to Section
     6.1(c)(ii), or, at the time of the termination of this Agreement, the
     Parent had the right to so terminate, then within two (2) Business Days
     after any of the conditions set forth in Section 6.1(c)(ii) are satisfied,
     the Company shall pay to the Parent the Termination Fee.

(iii)If this Agreement is terminated by the Parent pursuant to Section
     6.1(c)(iv), or at the time of the termination of this Agreement, the Parent
     had the right to so terminate, then within two (2) Business Days after such
     termination, the Company shall pay to the Parent the Termination Fee;
     provided, however, that the Company shall not be obligated to pay the
     Parent the Termination Fee pursuant to this Section 7.1(b)(iii) in the
     event that (y) the actions of Board of Directors of the Company that gave
     rise to the Parent's right to terminate under Section 6.1(c)(iv) were the
     result of the occurrence of an event which had, or was reasonably expected
     to have, a Material Adverse Effect on the Parent or had caused, or was
     reasonably expected to cause, the Parent to suffer a Material Adverse
     Change and (z) the Board of Directors of the Company made a good faith
     determination, based upon the advice of its legal counsel as to legal
     matters, that such actions were necessary in order to comply with its
     fiduciary duties to the Company stockholders under applicable law. (iv) If
     this Agreement is terminated by the Company pursuant to Section 6.1(d),
     then the Company shall pay to the Parent the Termination Fee prior to such
     termination as provided in Section 6.1(d).

(v)  If following a Takeover Proposal, this Agreement is terminated by either
     the Parent or the Company pursuant to Section 6.1(e), and within 12 months
     after such termination the Company executes with a third party a definitive
     agreement to implement a Takeover Proposal, then the Company shall pay to
     the Parent the Termination Fee within two (2) Business Days after the
     execution of such agreement.

                                       62
<PAGE>
 
(vi) If following a Takeover Proposal, this Agreement is terminated by the
     Company pursuant to Section 6.1(f), and within 12 months after such
     termination the Company executes with a third party a definitive agreement
     to implement a Takeover Proposal, then the Company shall pay to the Parent
     the Termination Fee within two (2) Business Days after the execution of
     such agreement.

(vii)For purposes of this Section 7.1(b), whenever the Company shall be
     obligated to pay the Termination Fee, the Company shall pay the Parent by
     wire transfer to an account specified by the Parent.

8.          MISCELLANEOUS.
            ------------- 
8.1         Certification of the Company's Shareholder Votes, Etc.
            ----------------------------------------------------- 

          Prior to the Effective Date, the Company shall deliver to the Parent
          and the Merger Subsidiary a certificate of its Secretary or Assistant
          Secretary setting forth (a) the number of shares of its capital stock
          outstanding and entitled to vote on the adoption of this Agreement,
          (b) the number of votes pertaining to such shares of capital stock,
          and (c) the number of votes cast in favor of and against the approval
          of this Agreement.

8.2         Certification of the Parent's Stockholder Votes, Etc.
            ---------------------------------------------------- 

          Prior to the Effective Date, the Parent shall deliver to the Company
          and the Merger Subsidiary a certificate of its Secretary or Assistant
          Secretary setting forth that the Parent, in its capacity as sole
          stockholder of the Merger Subsidiary, has adopted this Agreement and
          approved the Merger in accordance with the DGCL.

8.3         Termination of Covenants, Representations and Warranties.
            -------------------------------------------------------- 

          The respective covenants, representations and warranties of the
          parties hereto contained in Articles 3 and 4 hereof and in the
          Schedules shall expire and be terminated and extinguished at the
          Effective Time, and none of the parties hereto shall thereafter be
          under any liability whatsoever with respect to such covenants,
          representations and warranties.  This Section 8.3 shall have no effect
          upon any other obligations hereunder of any of the parties hereto,
          whether to be performed before or after the effectiveness of the
          Merger.

8.4         Certain Tax Matters.
            ------------------- 
(a)  The Parent and the Merger Subsidiary hereby jointly and severally
     represent, warrant and covenant to the Company and the Surviving
     Corporation as follows:

                                       63
<PAGE>
 
(i)  The fair market value of Parent Common Stock and other consideration
     received by each Company stockholder will be approximately equal to the
     fair market value of Company Common Stock surrendered in the exchange;

(ii) Following the Merger, the Surviving Corporation will hold at least 90
     percent of the fair market value of the Company's net assets and at least
     70 percent of the fair market value of the Company's gross assets and at
     least 90 percent of the fair market value of the Merger Subsidiary's net
     assets and at least 70 percent of the fair market value of the Merger
     Subsidiary's gross assets held immediately prior to the Merger.  For
     purposes of the preceding sentence, amounts paid by the Company or the
     Merger Subsidiary to stockholders who receive cash or other property,
     amounts used by the Company or the Merger Subsidiary to pay reorganization
     expenses and all redemptions and distributions (except for regular, normal
     dividends) made by the Company will be included as assets of the Company or
     the Merger Subsidiary, respectively, immediately prior to the Merger;

(iii)Prior to the Merger, the Parent will be in control of the Merger
     Subsidiary within the meaning of Section 368(c) of the Code;

(iv) The Surviving Corporation has no plan or intention to issue additional
     shares of its stock that would result in the Parent's losing control of the
     Surviving Corporation within the meaning of Section 368(c)(1) of the Code;

(v)  The Parent has no plan or intention to reacquire any of the shares of
     Parent Common Stock to be issued in the Merger, nor does the Parent have
     any knowledge of a plan or intention on the part of a "related party" to
     the Parent (as such term is defined in the regulations under Section 368 of
     the Code) to acquire any of the shares of Parent Common Stock to be issued
     in the Merger;

(vi) The Parent has no plan or intention to liquidate the Surviving Corporation,
     to merge the Surviving Corporation with or into another corporation, to
     sell or otherwise dispose of the stock of the Surviving Corporation, except
     for transfers of stock to corporations controlled by the Parent, or to
     cause the Surviving Corporation to sell or otherwise dispose of any of its
     assets or of any of the assets acquired from the Merger Subsidiary, except
     for dispositions made in the ordinary course of business or transfers of
     assets to a corporation controlled by the Surviving Corporation;

                                       64
<PAGE>
 
(vii) The Merger Subsidiary will have no liabilities assumed by the
      Surviving Corporation, and it will not transfer to the Surviving
      Corporation any assets subject to liabilities, in the Merger;

(viii)Following the Merger, the Surviving Corporation will continue the
      historic business of the Company or use a significant portion of its
      historic business assets in a business;

(ix)  The Parent, the Merger Subsidiary, the Company and the shareholders of the
      Company will pay their respective expenses, if any, incurred in connection
      with the Merger;

(x)   There is no intercorporate indebtedness existing between the Parent and 
      the Company or between the Merger Subsidiary and the Company that was
      issued, acquired or will be settled at a discount;

(xi)  The Parent does not own, nor has it owned during the past five (5) years,
      any shares of the stock of the Company;

(xii) No two parties to the Merger are investment companies as defined in
      Sections 368(a)(2)(F)(iii) and (iv) of the Code; and

(xiii)None of the compensation to be received by any shareholder-employees
      of the Company under any employment agreement will be separate
      consideration for, or allocable to, any of their shares of Company Common
      Stock; none of the shares of Parent Common Stock received by any
      shareholder-employees will be separate consideration for, or allocable to,
      any employment agreement; and the compensation paid to any shareholder-
      employees under any employment agreement will be for services actually
      rendered and will be commensurate with amounts paid to third parties
      bargaining at arm's length for similar services.

(b)  The Company and PL hereby jointly and severally represent, warrant and
     covenant to the Parent and the Merger Subsidiary as follows:

(i)  The fair market value of Parent Common Stock and other consideration
     received by each Company stockholder will be approximately equal to the
     fair market value of Company Common Stock surrendered in the exchange;

(ii) Following the Merger, the Surviving Corporation will hold at least 90
     percent of the fair market value of the Company's net assets and at least
     70 percent of the fair market value of the Company's gross assets and at
     least 90 percent of the fair market value of Merger Subsidiary's net assets
     and at least 70 percent of the fair market

                                       65
<PAGE>
 
      value of Merger Subsidiary's gross assets held immediately prior to the
      Merger. For purposes of the preceding sentence, amounts paid by the
      Company or the Merger Subsidiary to stockholders who receive cash or other
      property, amounts used by the Company or the Merger Subsidiary to pay
      reorganization expenses and all redemptions and distributions (except for
      regular, normal dividends) made by the Company will be included as assets
      of the Company or the Merger Subsidiary, respectively, immediately prior
      to the Merger;

(iii) Prior to the Merger, neither the Company nor PL will take any action
      which would disqualify the Merger for treatment as a tax-free transaction
      under the Code;

(iv)  Neither the Company nor PL has any knowledge of a plan or intention on the
      part of the holders of Company Common Stock to sell or transfer to the
      Parent or to a "related party" to the Parent (as such term is defined in
      the regulations under Section 368 of the Code) any of the shares of Parent
      Common Stock to be received by such holders in the Merger;

(v)   The Parent, the Merger Subsidiary, the Company and the shareholders of the
      Company will pay their respective expenses, if any, incurred in connection
      with the Merger;

(vi)  There is no intercorporate indebtedness existing between the Parent and 
      the Company or between the Merger Subsidiary and the Company that was
      issued, acquired or will be settled at a discount;

(vii) At the time of the Merger, the Company will not have outstanding any
      warrants, options, convertible securities or any other type of right
      pursuant to which any person could acquire stock in the Company that, if
      exercised or converted, would affect the Parent's acquisition or retention
      of control of the Company, as defined in Section 368(c) of the Code;

(viii)On the date of the Merger, the fair market value of the assets of
      the Company will exceed the sum of its liabilities, plus the amount of
      liabilities, if any, to which the assets are subject; and

(ix)  No two parties to the Merger are investment companies as defined in
      Sections 368(a)(2)(F)(iii) and (iv) of the Code.

(c)  Neither the Parent nor the Surviving Corporation shall have any liability
     to the holders of the Company Common Stock with respect to the tax
     consequences resulting from the transactions contemplated by this

                                       66
<PAGE>
 
     Agreement except to the extent that: (A) the representations and warranties
     of the Parent and the Merger Subsidiary set forth in Section 8.4(a) hereof
     are not true and correct on the Effective Date or (B) the covenants of the
     Parent and the Merger Subsidiary set forth in Section 8.4(a) are not
     performed on and after the Effective Date.

8.5         Execution in Counterparts.
            ------------------------- 

          For the convenience of the parties, this Agreement and any amendments,
          supplements, waivers and modifications may be executed in one or more
          counterparts, each of which shall be deemed an original, but all of
          which together shall constitute one and the same document.

8.6         Waivers and Amendments.
            ---------------------- 

          Prior to the Effective Date, this Agreement may be amended, modified
          and supplemented in writing by the parties hereto, and any failure of
          any of the parties hereto to comply with any of its obligations,
          agreements or conditions as set forth herein may be expressly waived
          in writing by the other parties hereto.

8.7         Confidentiality.
            --------------- 

          The Company and the Parent agree that they shall abide by the terms of
          the Confidentiality Agreement between them dated March 27, 1998 (as
          supplemented) (the "Confidentiality Agreement") and the Reciprocal
          Confidentiality Agreement between them dated _________________, 1998
          (the "Reciprocal Confidentiality Agreement"), respectively, and such
          confidentiality agreements shall continue in effect notwithstanding
          the execution of this Agreement.

8.8         Indemnification; Directors and Officers Insurance.
            --------------------------------------------------

          For six (6) years from and after the Effective Time, the Parent agrees
          to cause the Surviving Corporation to, and shall guarantee the
          obligation of the Surviving Corporation to, indemnify and hold
          harmless all past and present officers and directors of the Company to
          the same extent such Persons are indemnified as of the date of this
          Agreement by the Company and PL pursuant to their Company's
          Certificate of Incorporation, Bylaws or agreements in existence on the
          date hereof for acts or omissions occurring at or prior to the
          Effective Time (including, without limitation, acts or omissions
          relating to the negotiation, execution and performance of this
          Agreement and the Company Option Agreement and the transactions
          contemplated hereby and thereby).  The Parent shall provide, or shall
          cause the Surviving Corporation to provide, for an aggregate period of
          not less than six (6) years from the Effective Time, the Company's
          current directors and officers an insurance and indemnification policy
          that provides coverage for events occurring prior to the Effective
          Time (the "D&O Insurance") that is

                                       67
<PAGE>
 
          substantially similar (with respect to limits and deductibles) to the
          Company's existing policy or, if substantially equivalent insurance
          coverage is unavailable, the best available coverage; provided,
          however, that the Surviving Corporation shall not be required to pay
          any annual premium for D&O Insurance which is greater than 200% of the
          most recent annual premiums paid by the Company for D&O Insurance.

8.9         Notices.
            ------- 

          All notices, requests, demands and other communications required or
          permitted hereunder shall be in writing and shall be deemed to have
          been duly given upon receipt when delivered by hand against receipt,
          telecopied (upon confirmation of receipt thereof) or mailed, certified
          or registered mail, return receipt requested, postage prepaid:

          To the Company:


          Lloyd H. Malchow, President and CEO
          320 Lakeside Drive
          Suite A
          Foster City, California

               with a copy to:


               Henry Lesser, Esquire
               Heller Ehrman White & McAuliffe
               525 University Avenue
               Palo Alto, California  94301-1800
               Telecopy Number:  (650) 324-0638

          To the Parent or the Merger Subsidiary:


          Roderick P. Jackson, Senior Vice President
          Chestnut Ridge Road
          P.O. Box 4310
          Morgantown, West Virginia  26505
          Telecopy Number:  (304) 599-7284

               with a copy to:


               John R. Previs, Esquire/JoEllen Lyons, Esquire
               Buchanan Ingersoll Professional Corporation
               One Oxford Centre
               301 Grant Street
               Pittsburgh, Pennsylvania  15219
               Telecopy Number:  (412) 562-1041

                                       68
<PAGE>
 
          or to such other address as specified in a notice given in like
          manner.

8.10        Entire Agreement; No Third-Party Beneficiaries; Rights of Ownership.
            ------------------------------------------------------------------- 

          This Agreement (including the documents and the instruments referred
          to herein) (a) constitutes the entire agreement and supersedes all
          prior agreements and understandings, both written and oral, among the
          parties with respect to the subject matter hereof and thereof, and (b)
          is not intended to confer upon any Person other than the parties
          hereto or thereto and the indemnitees under Section 8.8 any rights or
          remedies hereunder or thereunder.

8.11        Governing Law.
            ------------- 
          This Agreement shall be governed by and construed in accordance with
          the laws of the State of Delaware without regard to any applicable
          conflicts of laws provisions.

8.12        Partial Invalidity.
            -------------------

          Wherever possible, each provision hereof shall be interpreted in such
          a manner as to be effective and valid under applicable law, but in
          case any one or more of the provisions contained herein shall, for any
          reason, be held to be invalid, illegal or unenforceable in any
          respect, it shall, to the extent possible, be construed in such manner
          as to be legal, valid and enforceable but so as to most nearly retain
          the intent of the parties.  The invalidity, illegality or
          unenforceability of any provision of this Agreement shall not affect
          any other provisions of this Agreement and such provisions shall
          remain in full force and effect.

8.13        Publicity.
            --------- 

          Except as otherwise required by law or the rules of the SEC, the NYSE
          (with respect to the Parent) or the NASD (with respect to the
          Company), for so long as this Agreement is in effect, neither the
          Parent nor the Company shall, nor shall either permit any of its
          respective subsidiaries to, issue or cause the publication of any
          press release or other public announcement with respect to the
          transactions contemplated by this Agreement without the consent of the
          other party as to the nature, contents and dissemination thereof, in
          which case the party proposing such publication shall deliver a copy
          of such release or announcement to the other party along with its
          request for consent, which consent shall not be unreasonably withheld.

8.14        Defined Terms.
            ------------- 
          All capitalized terms used herein without definition shall have the
          meanings given them at the places in this Agreement indicated in
          Appendix A.
          ---------- 

                                       69
<PAGE>
 
8.15        Benefit Plans.
            ------------- 
(a)  The eligibility of each employee of the Company (and his or her spouse and
     dependents) to participate in the welfare benefit plans of the Parent or
     the Surviving Corporation after the Effective Time and the coverage of each
     such participant in each such plan shall be determined without regard to
     any preexisting condition, waiting period, actively-at-work or similar
     exclusion or condition, except for any such condition or exclusion to which
     the employee is subject under the applicable welfare plan of the Company as
     of the Effective Time.  Participants in such plans of the Company shall
     receive credit, under the welfare benefit plans of the Parent or the
     Surviving Corporation in which they participate after the Effective Time,
     toward annual co-insurance and deductible limitations and requirements for
     any payments made for eligible charges incurred by them during the calendar
     year in which the Effective Time occurs under the applicable welfare plans
     of the Company.  In addition, employees of the Surviving Corporation shall
     receive credit, for purposes of determining vesting and eligibility under
     its retirement, welfare, vacation and similar plans or policies, for
     service with the Company prior to the Effective Time.

(b)  The Persons employed by the Company immediately prior to the Effective Time
     shall be eligible to participate in the employment severance programs
     provided by the Parent or the Surviving Corporation from time to time, and
     such persons shall receive credit under such programs for services with the
     Company prior to the Effective Date.

8.16        Enforcement of Agreement.
            ------------------------ 

          The parties hereto agree that irreparable damage would occur in the
          event that any of the provisions of this Agreement was not performed
          in accordance with its specific terms or was otherwise breached. It is
          accordingly agreed that the parties shall be entitled to an injunction
          to prevent breaches of this Agreement and to enforce specifically the
          terms and provisions hereof in any Delaware Chancery Court, this being
          in addition to any other remedy to which they are entitled at law or
          equity.  Notwithstanding the foregoing, if jurisdiction does not
          properly lie in the Delaware Chancery Court, the parties shall submit
          to the jurisdiction of the United States Federal District Court for
          the District of Delaware. The parties agree that such courts shall
          have exclusive jurisdiction to consider any claims hereunder or
          relating hereto.

8.17        Waiver of Jury Trial.
            -------------------- 

          Each party acknowledges and agrees that any controversy which may
          arise under this Agreement is likely to involve complicated and
          difficult issues, and therefore each such party hereby irrevocably and
          unconditionally waives any right such

                                       70
<PAGE>
 
          party may have to a trial by jury in respect of any litigation
          directly or indirectly arising out of or relating to this Agreement,
          or the transactions contemplated by this Agreement. Each party
          certifies and acknowledges that (i) no representative, agent or
          attorney of any other party has represented, expressly or otherwise,
          that such other party would not, in the event of litigation, seek to
          enforce the foregoing waiver, (ii) each party understands and has
          considered the implications of this waiver, (iii) each party makes
          this waiver voluntarily, and (iv) each party has been induced to enter
          into this Agreement by, among other things, the mutual waivers and
          certifications in this Section 8.17.

8.18        No Presumption Against the Draftsman.
           ------------------------------------ 

          Each party having been represented in the negotiation of this
          Agreement, and having had ample opportunity to review the language
          hereof, there shall be no presumption against any party on the ground
          that such party was responsible for preparing this Agreement or any
          part thereof.

                                       71
<PAGE>
 
     IN WITNESS WHEREOF, this Agreement has been executed by each of the
Constituent Corporations and the Parent, all on the date first above written.

                                    PENEDERM INCORPORATED

 


Attest:                                        By:
       ----------------------------               ----------------------------
        Name:  Michael A. Bates                   Name:  Lloyd H. Malchow
        Title:  Vice President, Finance and       Title:  President and CEO
                Administration, Chief Financial
                Officer

                                    MLI ACQUISITION CORP.



Attest:                                        By:
       ----------------------------               ----------------------------
        Name:  Donald C. Schilling                Name:  Roderick P. Jackson
        Title:  Vice President Finance            Title:  President

                                    MYLAN LABORATORIES INC.



Attest:                                        By:
       ----------------------------               ----------------------------
        Name:  Donald C. Schilling                Name:  Roderick P. Jackson
        Title:  Vice President Finance            Title:  Senior Vice President



                                       72
<PAGE>
 
                                   APPENDIX A

                                  GLOSSARY OF

                        DEFINED TERMS/SECTION REFERENCES

                                       IN

                          AGREEMENT AND PLAN OF MERGER

                                  BY AND AMONG

                                     [MOON]

                                      AND

                             MLI ACQUISITION CORP.

                                      AND

                                    [EARTH]

<TABLE>
<CAPTION>
DEFINED TERM                                                            SECTION REFERENCE
- ------------                                                            -----------------
<S>                                                                     <C>
Agreement                                                               Preamble
- ---------                                                               --------
Amended and Restated Certificate of Incorporation                       Section 1.2
Business Day                                                            Section 2.4
Certificates                                                            Section 2.1(b)(ii)
Closing                                                                 Section 2.4
Code                                                                    Recital 5
Common Stock Investment Agreement                                       Section 3.1(b)(i)
Company                                                                 Preamble
Company Affiliates                                                      Section 3.1(s)
Company Common Stock                                                    Recital 7
Company Contracts                                                       Section 3.1(m)
Company Employee Stock Purchase Plan                                    Section 2.3(d)
Company Financial Statements                                            Section 3.1(e)
Company 401(k) Plan                                                     Section 3.1(b)(i)
</TABLE>

                                       73
<PAGE>
 
<TABLE>
<CAPTION>
DEFINED TERM                                                            SECTION REFERENCE
- ------------                                                            -----------------
<S>                                                                     <C>
Company Option Agreement                                                Recital 7
Company Permits                                                         Section 3.1(h)
Company Preferred Stock                                                 Section 3.1(b)(i)
Company Representatives                                                 Section 4.1(f)(i)
Company Rights Plan                                                     Section 3.1(c)
Company SEC Documents                                                   Section 3.1(e)
Company Stock Option Plans                                              Section 2.3(a)
Company Stock Options                                                   Section 3.1(b)(i)
Company Warrant                                                         Section 2.3(b)
Company Warrant Shares                                                  Section 2.3(b)
Confidentiality Agreement                                               Section 8.7
Constituent Corporations                                                Preamble
Contract Manufacturer                                                   Section 3.1(k)(iii)
D&O Insurance                                                           Section 8.8
DGCL                                                                    Recital 2
Dillon Read                                                             Section 3.2(n)
Drug Regulatory Agency                                                  Section 3.1(k)(i)
Effective Date                                                          Section 1.4
Effective Time                                                          Section 1.4
Employee Benefit Plan                                                   Section 3.1(cc)(i)
Environmental Laws                                                      Section 3.1(ii)(ii)
ERISA                                                                   Section 3.1(cc)(i)
Exchange Act                                                            Section 3.1(d)
Exchange Agent                                                          Section 2.1(b)(i)
Exchange Fund                                                           Section 2.1(b)(i)
Exchange Ratio                                                          Section 2.1(a)
FDA                                                                     Section 3.1(k)(ii)
FDA Act                                                                 Section 3.1(k)(i)
Governmental Entity                                                     Section 3.1(d)

</TABLE>

                                       74
<PAGE>
 
<TABLE>
<CAPTION>
DEFINED TERM                                                            SECTION REFERENCE
- ------------                                                            -----------------
<S>                                                                     <C>
HSR Act                                                                 Section 3.1(d)
Investor                                                                Section 3.1(b)(i)
IRS                                                                     Section 3.1(i)
knowledge of the Company                                                Section 3.1(j)
knowledge of the Parent                                                 Section 3.2(i)
material                                                                Section 3.1(ee)
Material Adverse Change                                                 Section 3.1(a)(i)
Material Adverse Effect                                                 Section 3.1(a)(i)
Merger                                                                  Recital 2
Merger Subsidiary                                                       Preamble
NASD                                                                    Section 3.1(d)
NASDAQ                                                                  Section 3.1(d)
NYSE                                                                    Section 2.1(d)
Parent                                                                  Preamble
Parent Affiliates                                                       Section 3.2(p)
Parent Common Stock                                                     Section 2.1(a)
Parent Financial Statements                                             Section 3.2(e)
Parent Permits                                                          Section 3.2(h)
Parent Preferred Stock                                                  Section 3.2(b)(i)
Parent SEC Documents                                                    Section 3.2(e)
Parent Stock Option Plans                                               Section 3.2(b)(i)
Parent Stock Options                                                    Section 3.2(b)(i)
PCBs                                                                    Section 3.1(ii)(i)
Person                                                                  Section 4.1(f)(v)
PL                                                                      Section 3.1(a)(ii)
Prospectus/Proxy Statement                                              Section 3.1(c)
Reciprocal Confidentiality Agreement                                    Section 8.7
Registration Statement                                                  Section 3.2(c)
Regulated Substance                                                     Section 3.1(ii)(ii)
</TABLE>

                                       75
<PAGE>
 
<TABLE>
<CAPTION>
DEFINED TERM                                                            SECTION REFERENCE
- ------------                                                            -----------------
<S>                                                                     <C>
Remedies                                                                Section 6.3
Scheduled Closing Date                                                  Section 2.4
SEC                                                                     Section 2.3(c)
Section 414 Affiliate                                                   Section 3.1(cc)(iv)
Securities Act                                                          Section 3.1(d)
Stockholders Meeting                                                    Section 4.1(m)
Subsidiary                                                              Section 3.2(a)
Subsidiary Common Stock                                                 Section 2.2
Superior Proposal                                                       Section 4.1(f)(iv)
Surviving Corporation                                                   Recital 2
Takeover Proposal                                                       Section 4.1(f)(iii)
Tax Return                                                              Section 3.1(i)
Taxes                                                                   Section 3.1(i)
Termination Date                                                        Section 6.1(e)
Termination Fee                                                         Section 7.1(b)(i)
Transaction Agreements                                                  Section 3.1(l)
Unexercised Options                                                     Section 2.3(a)
Voting Agreements                                                       Recital 8
Warrant Holder                                                          Section 2.3(b)
</TABLE>

                                       76

<PAGE>
                                                                    Exhibit 99.1

 
                             STOCK OPTION AGREEMENT

     STOCK OPTION AGREEMENT, dated June 24, 1998 (the "Agreement"), by and
between Mylan Laboratories Inc., a Pennsylvania corporation ("Parent"), and
Penederm Incorporated, a Delaware corporation (the "Company").

                                    RECITALS
                                    --------

     A.  Concurrently with the execution and delivery of this Agreement, the
Company, Parent and MLI Acquisition Corp., a Delaware corporation and wholly
owned subsidiary of Parent ("Subsidiary") are entering into an Agreement and
Plan of Merger, dated as of the date hereof (the "Merger Agreement"), providing
for, among other things, the merger of Subsidiary  with and into the Company
(the "Merger"), with the Company as the surviving corporation in the Merger.

     B.  As a condition and inducement to Parent's and Subsidiary's willingness
to enter into the Merger Agreement, Parent has requested that the Company agree,
and the Company has agreed, to grant Parent an option to purchase shares of the
Company's common stock on the terms and subject to the conditions set forth
herein.

     C.  Capitalized terms not otherwise defined herein shall have the meanings
ascribed to them in the Merger Agreement.

     NOW, THEREFORE, in consideration of the foregoing and the respective
representations, warranties, covenants and agreements set forth herein and in
the Merger Agreement and for other good and valuable consideration, the receipt
and adequacy of which are hereby acknowledged, the parties hereto, intending to
be legally bound, agree as follows:

1.  Grant of Option.  Subject to the terms and conditions set forth herein, the
    ---------------                                                            
Company hereby grants to Parent an unconditional, irrevocable option (the
"Option") to purchase up to 1,717,878 (as adjusted as set forth herein) fully
paid and nonassessable shares (individually an "Option Share" and collectively
the "Option Shares") of Common Stock, par value $.01 per share of Company
("Company Common Stock"), at a purchase price of $20 (as adjusted as set forth
herein) per Option Share (the "Purchase Price") payable in cash; provided,
                                                                 -------- 
however, that in no event shall the number of Option Shares for which the Option
- -------                                                                         
is exercisable together with the number of shares owned by Parent, if any,
exceed 19.9% of the Company's issued and outstanding shares of Company Common
Stock without giving effect to any shares subject or issued pursuant to the
Option.  The number of Option Shares that may be received upon exercise of the
Option and the Purchase Price are each subject to adjustment as set forth in
Section 9 hereof and as otherwise provided herein.
<PAGE>
 
2.  Exercise of Option.  (a) Subject to any applicable requirements of law,
    ------------------                                                     
Parent may exercise the Option, in whole or in part, at any time or from time to
time after the occurrence of any one of the following events (a "Purchase
Event"):  (A) any of the following occurs prior to the earlier of the Effective
Time or the termination of the Merger Agreement in accordance with its terms:
(i) any Person (other than Parent or any of its subsidiaries) shall have
commenced (as such term is defined in Rule 14d-2 under the Securities Exchange
Act of 1934 (the "Exchange Act")) a tender offer, or shall have filed a
registration statement under the Securities Act of 1933 (the "Securities Act")
with respect to an exchange offer, to purchase any shares of Company Common
Stock such that, upon consummation of such offer, such person or a "group" (as
such term is defined under the Exchange Act) of which such person is a member
shall have acquired beneficial ownership (as such term is defined in Rule 13d-3
of the Exchange Act), or the right to acquire beneficial ownership, of 25% or
more of the then outstanding Company Common Stock; (ii) the Company or any of
its subsidiaries shall have authorized, recommended, proposed or publicly
announced an intention to authorize, recommend or propose, or entered into, an
agreement, including without limitation, an agreement in principle, with any
person (other than Parent or any of its subsidiaries) to effect or provide for
the consummation of a Takeover Proposal; (iii) any Person (other than Parent or
any of its subsidiaries) shall solicit proxies or consents or announce a bona
fide intention to solicit proxies or consents from the Company's stockholders
(y) in opposition to the Merger, the Merger Agreement or any related
transactions or (z) relating to an Acquisition Transaction (other than
solicitations of stockholders seeking approval of the Merger, the Merger
Agreement or any related transactions), and the stockholders of the Company
shall have failed to approve the Merger; or (iv) any Person (other than Parent
or any of its subsidiaries) shall have acquired beneficial ownership (as such
term is defined in Rule 13d-3 under the Exchange Act) or the right to acquire
beneficial ownership of, or any "group" (as such term is defined under the
Exchange Act) shall have been formed which beneficially owns or has the right to
acquire beneficial ownership of, shares of Company Common Stock (other than
trust account shares) aggregating 25% or more of the then outstanding Company
Common Stock; or (B) the termination of the Merger Agreement under circumstances
entitling Parent to payment of the Termination Fee within 2 Business Days of
such termination under any of the provisions of Section 7.1(b) of the Merger
Agreement; or (C) within twelve (12) months after the Merger Agreement is
terminated pursuant to Section 6.1(e) or (f) thereof, the Company executes a
definitive agreement to implement a Takeover Proposal with a third party who had
submitted a Takeover Proposal prior to the Termination Date (a "Proponent"); or
(D) within six (6) months after the Merger Agreement is terminated pursuant to
Section 6.1(e) or (f) thereof, the Company executes a definitive agreement to
implement a Takeover Proposal with a third party other than a Proponent provided
that the Company received a Takeover Proposal prior to the Termination Date.

                                      -2-
<PAGE>
 
(b)  Except as provided in the last sentence of this Section 2(b) and Section 15
     hereof, the Option shall terminate and be of no further force and effect
     upon the earliest to occur (the "Expiration Date") of (A) the Effective
     Time, (B) 12 months after the first occurrence of a Purchase Event, of the
     type described in subclauses (A)(i) through (iv) of Section 2(a) hereof or
     subclause (B) of Section 2(a) hereof and (C) six months after the first
     occurrence of a Purchase Event of the type described in subclauses (B) or
     (C) of Section 2(a) hereof. Notwithstanding the termination of the Option,
     Parent shall be entitled to purchase the Option Shares if it has exercised
     the Option in accordance with the terms hereof prior to the termination of
     the Option and the termination of the Option shall not affect any rights
     hereunder which by their terms do not terminate or expire prior to or as of
     such termination.

(c)  In the event that Parent wishes to exercise the Option, it shall send to
     the Company a written notice (the date of which being herein referred to as
     the "Notice Date") specifying (i) the total number of Option Shares it
     wishes to purchase pursuant to such exercise and (ii) a date not earlier
     than three business days nor later than 20 business days from the Notice
     Date for the closing of such purchase (the "Option Closing Date");
     provided, however, that (i) if the closing of the purchase and sale
     --------  --------                                                 
     pursuant to the Option (the "Option Closing") cannot be consummated by
     reason of any applicable judgment, decree, order, law or regulation, the
     period of time that otherwise would run pursuant to this sentence shall run
     instead from the date on which such restriction on consummation has expired
     or been terminated and (ii) without limiting the foregoing, if prior
     notification to or approval of any regulatory authority is required in
     connection with such purchase, Parent and the Company shall promptly file
     the required notice or application for approval and shall cooperate in the
     expeditious filing of such notice or application, and the period of time
     that otherwise would run pursuant to this sentence shall run instead from
     the date on which, as the case may be, (A) any required notification period
     has expired or been terminated or (B) any required approval has been
     obtained, and in either event, any requisite waiting period has expired or
     been terminated.  Except as otherwise agreed in writing by the parties, the
     place of the Option Closing shall be at the offices of Buchanan Ingersoll
     Professional Corporation, One Oxford Centre, 301 Grant Street, 20th Floor,
     Pittsburgh, PA  15219-1410, and the time of the Option Closing shall be
     10:00 a.m. (Eastern Time) on the Option Closing Date.

3.  Payment and Delivery of Certificates.  (a) At the Option Closing, Parent
    ------------------------------------                                    
shall deliver to the Company the Purchase Price for the Option Shares so
designated and being purchased in immediately available funds by wire transfer
to a bank account designated in writing by the Company or by certified check or
bank check in an amount equal to the Purchase Price multiplied by the number of
Option Shares being purchased.  At any Option Closing, Parent shall also deliver
a letter, in form and substance reasonable acceptable to the Company, agreeing
that Parent will not offer to sell or otherwise dispose of such Option Shares in
violation of applicable law or the provisions of this Agreement.
 
(b)  At any Option Closing, simultaneously with the delivery of the Purchase
     Price as provided in Section 3(a), the Company shall deliver to Parent (i)
     a certificate or certificates representing the Option Shares to be
     purchased at the Option Closing, which Option Shares shall be free and
     clear of all liens, claims, charges and encumbrances of any kind whatsoever
     and (ii) if the Option should be exercised in part only, a new Option
     evidencing the rights of the Parent to purchase the balance of the Option
     Shares purchasable hereunder in the form of a Stock Option Agreement
     identical to this Agreement save only the number of Option Shares subject
     thereto.  If at the time of issuance of the Option Shares pursuant to the
     exercise of the Option hereunder, the Company shall not have redeemed any
     rights issued under the Company Shareholders Rights Plan dated November 20,
     1996 (the "Company Rights Plan"), or shall have issued any similar rights,
     then each Option Share issued pursuant to such exercise shall also
     represent a corresponding right or security or new rights with terms
     substantially the

                                      -3-
<PAGE>
 
     same as and at least as favorable to Parent as are provided under the
     Company Rights Plan or any similar agreement then in effect.

(c)  Certificates for the Option Shares delivered at the Option Closing shall
     have typed or printed thereon a restrictive legend which shall read
     substantially as follows:

          "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
          REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY BE
          REOFFERED OR SOLD ONLY IF SO REGISTERED OR IF AN EXEMPTION FROM SUCH
          REGISTRATION IS AVAILABLE.  SUCH SECURITIES ARE ALSO SUBJECT TO
          ADDITIONAL RESTRICTIONS ON TRANSFER AS SET FORTH IN THE STOCK OPTION
          AGREEMENT, DATED JUNE 24, 1998, A COPY OF WHICH MAY BE OBTAINED FROM
          THE SECRETARY OF PENEDERM INCORPORATED CORPORATION AT ITS PRINCIPAL
          EXECUTIVE OFFICES."

(d)  It is understood and agreed that:  (i) the reference to the resale
     restrictions of the Securities Act of 1933, as amended (the  "Securities
     Act"), in the above legend shall be removed by delivery of substitute
     certificate(s) without such reference if the Parent shall have delivered to
     the Company a copy of a letter from the staff of the Securities and
     Exchange Commission (the "SEC"), or an opinion of counsel, in form and
     substance satisfactory to the Company, to the effect that such legend is
     not required for purposes of the Securities Act; (ii) the reference to the
     provisions of this Agreement in the above legend shall be removed by
     delivery of substitute certificate(s) without such reference if the shares
     have been sold or transferred in compliance with the provisions of this
     Agreement and under circumstances that do not require the retention of such
     reference; and (iii) the legend shall be removed in its entirety as to
     those Option Shares with respect to which the conditions in the preceding
     clauses (i) and (ii) are both satisfied.  In addition, such certificates
     shall bear any other legend as may be required by law.

4.  Representations and Warranties of the Company.  The Company hereby
    ---------------------------------------------                     
represents and warrants to Parent as follows:

(a)  Due Authorization.  The Company has all requisite corporate power and
     -----------------                                                    
     authority to enter into this Agreement and to consummate the transactions
     contemplated hereby.  The execution and delivery of this Agreement by the
     Company and the consummation by the Company of the transactions
     contemplated hereby have been duly authorized by all necessary corporate
     action on the part of the Company.  This Agreement has been duly executed
     and delivered by the Company and constitutes a legal, valid and binding
     obligation of the Company, enforceable against the Company in accordance
     with its terms.

(b)  Authorized Stock.  The Company's representations and warranties in Section
     ----------------                                                          
     3.1(a) of the Merger Agreement are incorporated herein by reference.
     Without limiting the generality or effect of the foregoing, the Company has
     taken all necessary corporate and other action to authorize and reserve
     and, to permit it to issue, and, at all times from the date hereof

                                      -4-
<PAGE>
 
     until the obligation to deliver Option Shares upon the exercise of the
     Option terminates, shall have reserved for issuance, upon exercise of the
     Option, shares of Company Common Stock necessary for Parent to exercise the
     Option, and the Company shall take all necessary corporate action to
     authorize and reserve for issuance all additional shares of Company Common
     Stock or other securities which may be issued pursuant to Section 9 upon
     exercise of the Option. The shares of Company Common Stock to be issued
     upon due exercise of the Option, including all additional shares of Company
     Common Stock or other securities which may be issuable upon exercise of the
     Option or any Substitute Option pursuant to Section 9, upon issuance
     pursuant hereto, shall be duly and validly issued, fully paid and
     nonassessable, and shall be delivered free and clear of all liens, claims,
     charges and encumbrances of any kind or nature whatsoever, including
     without limitation any preemptive rights of any stockholder of the Company.

(c)  No Conflicts.  The execution and delivery of this Agreement does not, and
     ------------                                                             
     the consummation of the transactions contemplated by this Agreement and
     compliance with the provisions of this Agreement shall not, conflict with,
     or result in any violation of, or default (with or without notice or lapse
     of time or both) under, or give rise to a right of termination,
     cancellation or acceleration of any obligation or loss of a material
     benefit under, or result in the creation of any Lien upon any of the
     properties or assets of the Company or any of its subsidiaries under, (i)
     the certificate of incorporation or by-laws of the Company or the
     comparable organizational documents of any subsidiary of the Company, (ii)
     any loan or credit agreement, note, bond, mortgage, indenture, lease or
     other agreement, instrument, permit, concession, franchise or license
     applicable to the Company or any subsidiary of the Company or their
     respective properties or assets, or (iii) any judgment, order, decree,
     statute, law, ordinance, rule or regulation applicable to the Company or
     any subsidiary of the Company or their respective properties or assets,
     other than, in the case of clauses (ii) and (iii), any such conflicts,
     violations, defaults, rights, losses or Liens that individually or in the
     aggregate would not (x) have a Material Adverse Effect on the Company, (y)
     impair the ability of the Company to perform its obligations under this
     Agreement or the Merger Agreement, or (z) prevent or materially delay the
     consummation of any of the transactions contemplated by this Agreement.

(d)  State Takeover Statutes.  Neither Section 203 of the Delaware General
     -----------------------                                              
     Corporation Act, nor any similar provision contained in the charter or by-
     laws of the Company, is applicable to the acquisition of Option Shares
     pursuant to this Agreement.

5.  Representations and Warranties of Parent.  Parent hereby represents and
    ----------------------------------------                               
warrants to the Company that:

(a)  Due Authorization.  Parent has all requisite corporate power and authority
     -----------------                                                         
     to enter into this Agreement and to consummate the transactions
     contemplated hereby.  The execution and delivery of this Agreement by
     Parent and the consummation by Parent of the transactions contemplated
     hereby have been duly authorized by all necessary corporate action on the
     part of Parent.  This Agreement has been duly executed and delivered by
     Parent and constitutes a legal, valid and binding obligation of Parent,
     enforceable against Parent in accordance with its terms.

                                      -5-
<PAGE>
 
(b)  No Conflicts.  The execution and delivery of this Agreement does not, and
     ------------                                                             
     the consummation of the transactions contemplated by this Agreement and
     compliance with the provisions of this Agreement hereby shall not, conflict
     with or result in any violation of, or default (with or without notice or
     lapse of time or both) under, or give rise to a right of termination,
     cancellation or acceleration of any obligation or loss of a material
     benefit under, or result in the creation of any Lien upon any of the
     properties or assets of Parent under, (i) the certificate of incorporation
     or by-laws of Parent or the comparable organizational documents of Parent,
     (ii) any loan or credit agreement, note, bond, mortgage, indenture, lease
     or other agreement, instrument, permit, concession, franchise or license
     applicable to Parent or its properties or assets, or (iii) any judgment,
     order, decree, statute, law, ordinance, rule or regulation applicable to
     Parent or its properties or assets, other than, in the case of clauses (ii)
     and (iii), any such conflicts, violations, defaults, rights, losses or
     Liens that individually or in the aggregate would not (x) have a material
     adverse effect on Parent, (y) impair the ability of Parent to perform its
     obligations under this Agreement or the Merger Agreement, or (z) prevent or
     materially delay the consummation of any of the transactions contemplated
     by this Agreement.

(c)  Purchase Not for Distribution.  Any Option Shares or other securities
     -----------------------------                                        
     acquired by Parent upon exercise of the Option shall not be transferred or
     otherwise disposed of except in a transaction registered, or exempt from
     registration, under the Securities Act.

6.  Repurchase of Option at Request of Parent.  (a)  At the request of Parent
    -----------------------------------------                                
and in Parent's sole discretion, at any time during the period beginning upon
the first occurrence of a Repurchase Event (as defined in Section 6(c)) and
ending 6 months thereafter, the Company shall repurchase from Parent the Option
(unless the Option shall have expired or been terminated) and all shares of
Common Stock purchased by Parent upon exercise of the Option that are
beneficially owned by Parent on the date upon which Parent requests that the
Company repurchase the Option or Option Shares under this Section 6(a) (the
"Request Date").  Such repurchase shall be at an aggregate price (the "Put
Price") equal to the sum of:

          (x) the aggregate Purchase Price paid by Parent for all Option Shares
     previously purchased upon exercise of the Option that are beneficially
     owned by Parent on the Request Date;

          (y) the excess, if any, of the average of the last sales price for
     Company Common Stock for the ten trading days ending on the day immediately
     preceding the Put Closing Date (the "Market Price") over the Option Price
     paid by Parent for each share of Company Common Stock with respect to which
     the Option has been exercised that are beneficially owned by Parent on the
     Request Date, multiplied by the number of such shares; and

          (z) the excess, if any, of the Market Price of Company Common Stock at
     the Put Closing Date over the Option Price (determined as if the Put
     Closing Date were the Option Closing Date) multiplied by the number of
     Option Shares with respect to which the Option has not been exercised;
     provided that, in the case of Option Shares with respect to which the
     Option has been exercised but the Option Closing Date has not

                                      -6-
<PAGE>
 
     occurred, the Option Closing Date shall be suspended and the Option shall
     be treated, for purposes of this clause (z), as if it had not been
     exercised.

 
(b)  If Parent exercises its rights under this Section 6, the Company shall,
     within 10 business days after the Request Date (the "Put Closing Date"),
     pay the Put Price to Parent in immediately available funds, by wire
     transfer to a bank account designated by Parent, Parent shall, against
     receipt of the payment therefore, surrender to the Company the Option and
     the certificates evidencing Option Shares previously purchased upon
     exercise of the Option that are beneficially owned by Parent on the Request
     Date; and Parent shall be deemed to have represented and warranted that it
     has sole ownership of such Option Shares, free and clear of all liens,
     claims, charges, and encumbrances of any kind.  Notwithstanding the
     foregoing, if the Company is prohibited from paying all or any portion of
     the Put Price by reason of any applicable judgment, decree, order, law, or
     regulation, the Company shall immediately pay that portion of the Put Price
     that it is not prohibited from paying, shall from time to time thereafter
     immediately pay such further portion of the Put Price that it is not then
     prohibited from paying, and, in all cases, shall pay the balance of the Put
     Price within 10 business days after such prohibition has expired or been
     terminated.  Upon receipt of a partial payment of the Put Price, Parent
     shall surrender a portion of the Option and/or Option Shares, as selected
     by Parent, corresponding (as closely as practicable) to the portion of the
     Put Price received by Parent.

(c)  As used herein, a "Repurchase Event" means any of the following:  (i) a
     termination of the Merger Agreement by the Board of Directors of the
     Company under Section 6.1(d) of the Merger Agreement; (ii) an occurrence of
     both (A) a Purchase Event of the type described in subclauses (A),or (C) of
     Section 2(a) hereof other than a termination of the Merger Agreement
     referred to in clause (i) of this sentence and (B) consummation of a
     Takeover Proposal within twelve (12) months after termination of the Merger
     Agreement; (or) (iii) an occurrence of both (A) a Purchase Event of the
     type described in subclause (D) of Section 2(a) hereof and (B) consummation
     of a Takeover Proposal within six (6) months after the termination of the
     Merger Agreement.  A Repurchase Event referred to in clause (ii) or (iii)
     of the preceding sentence will occur when the last of the events referred
     to in clauses (ii)(A) and (ii) (B) occurs.

7.  Registration Rights.  Parent may, by written notice (the "Registration
    -------------------                                                   
Notice") request the Company to register under the Securities Act all or any
part of the capital stock of the Company acquired under this Agreement and
beneficially owned by Parent (the "Registrable Securities").  The Company
(and/or any Person designated by the Company) shall thereupon have the option
exercisable by written notice delivered to Parent within 10 business days after
the receipt of the Registration Notice, irrevocably to agree to purchase all or
any part of the Registrable Securities for cash at a price equal to the product
of (i) the number of Registrable Securities and (ii) the fair market value of
such shares.  Any such purchase of Registrable Securities by the Company
hereunder shall take place at a closing to be held at the principal executive
offices of the Company or its counsel at any reasonable date and time designated
by the Company and/or such designee in such notice within 20 business days after
delivery of such notice.  Any payment of the shares to be purchased shall be
made by delivery at the time of such closing of the purchase price for the
Registrable Securities in immediately available funds.  For purposes of his
Agreement the term Registrable Securities shall not include shares of capital

                                      -7-
<PAGE>
 
stock acquired under this Agreement that may be sold pursuant to Rule 144(k) of
the Securities Act.

          If the Company does not elect to exercise its option pursuant to this
Section 7 with respect to all Registrable Securities, it shall use its best
efforts to effect, as promptly as practicable, the registration under the
Securities Act of the unpurchased Registrable Securities; provided, however,
                                                          --------  --------
that (i) Parent shall be entitled to no more than an aggregate of two effective
registration statements hereunder and (ii) the Company will not be required to
file any such registration statement during any period of time (not to exceed 40
days after such request in the case of clause (A) below or 90 days in the case
of clauses (B) and (C) below) when (A) the Company is in possession of material
non-public information which it reasonably believes would be detrimental to be
disclosed at such time and, in the written opinion of counsel to such Company,
such information would have to be disclosed if a registration statement were
filed at that time; (B) such Company is required under the Securities Act to
include audited financial statements for any period in such registration
statement and such financial statements are not yet available for inclusion in
such registration statement; or (C) such Company determines, in its reasonable
judgment, that such registration would interfere with any financing, acquisition
or other material transaction involving the Company or any of its affiliates.
If consummation of the sale of any Registrable Securities pursuant to a
registration hereunder does not occur within 90 days after the filing with the
Securities and Exchange Commission of the registration statement becomes
effective, the provisions of this Section 7 shall again be applicable to any
proposed registration, provided, however, that neither party shall be entitled
                       -------- ---------                                     
to request more than two registrations pursuant to this Section 7.  The Company
shall use its reasonable best efforts to cause any Registrable Securities
registered pursuant to this Section 7 to be qualified for sale under the
securities or Blue Sky laws of such jurisdictions as Parent may reasonably
request and shall continue such registration or qualification in effect in such
jurisdiction; provided, however, that the Company shall not be required to
              --------  --------                                          
qualify to do business in, or consent to general service of process in, any
jurisdiction by reason of this provision.

          The registration rights set forth in this Section 7 are subject to the
condition that Parent shall provide the Company with such information with
respect to such holder's Registrable Securities, the plans for the distribution
thereof, and such other information with respect to such holder, as, in the
reasonable judgment of counsel for the Company, is necessary to enable the
Company to include in such registration statement all material facts required to
be disclosed with respect to a registration thereunder.

          A registration effected under this Section 7 shall be effected at the
Company's expense, except for underwriting discounts and commissions and the
fees and expenses of counsel to Parent, and the Company shall provide to any
underwriter such documentation (including certificates, opinions of counsel and
"comfort" letters from auditors) as are customary in connection with
underwritten public offerings as such underwriters may reasonably require.  In
connection with any such registration, the parties agree (i) to indemnify each
other and any underwriters in the customary manner and (ii) to enter into an
underwriting agreement in form and substance customary to transactions of this
type with any underwriters participating in such offering.

                                      -8-
<PAGE>
 
8.  Listing.  If shares of Company Common Stock or any other securities to be
    -------                                                                  
acquired upon exercise of the Option are then listed on the Nasdaq National
Market (or any other national securities exchange or national securities
quotation system), the Company, upon the request of Parent, shall promptly file
an application to list the shares of Company Common Stock or other securities to
be acquired upon exercise of the Option on the Nasdaq National Market (or such
other national securities exchange or national securities quotation system) and
shall use reasonable efforts to obtain approval of such listing as promptly as
practicable.

9.  Adjustment Upon Changes in Capitalization, Etc.  (a) In the event of any
    ----------------------------------------------                          
change in Company Common Stock by reason of a stock dividend, split-up, merger,
recapitalization, combination, exchange of shares or similar transaction, the
type and number of shares or securities subject to the Option, and the Purchase
Price therefor, shall be adjusted appropriately, and proper provision shall be
made in the agreements governing such transaction, so that Parent shall receive
upon exercise of the Option the number and class of shares or other securities
or property that Parent would have received in respect of Company Common Stock
if the Option had been exercised immediately prior to such event or the record
date therefor, as applicable.  Subject to Section 1, and without limiting the
parties' relative rights and obligations under the Merger Agreement, if any
additional shares of Company Common Stock are issued after the date of this
Agreement (other than pursuant to an event described in the first sentence of
this Section 9(a)), the number of shares of Company Common Stock subject to the
Option shall be adjusted so that, after such issuance, it equals 19.9% of the
number of shares of Company Common Stock then issued and outstanding, without
giving effect to any shares subject to or issued pursuant to the Option.
 
(b)  Without limiting the parties' relative rights and obligations under the
     Merger Agreement, in the event that the Company enters into an agreement
     (i) to consolidate with or merge into any person, other than Parent or one
     of its subsidiaries, and the Company shall not be the continuing or
     surviving corporation in such consolidation or merger, (ii) to permit any
     person, other than Subsidiary or one of Parent's other subsidiaries, to
     merge into the Company and the Company shall be the continuing or surviving
     corporation, but in connection with such merger, the shares of Company
     Common Stock outstanding immediately prior to the consummation of such
     merger shall be changed into or exchanged for stock or other securities of
     the Company or any other person or cash or any other property, or the
     shares of Company Common Stock outstanding immediately prior to the
     consummation of such merger shall, after such merger, represent less than
     50% of the outstanding voting securities of the merged company, or (iii) to
     sell or otherwise transfer all or substantially all of its assets to any
     person, other than Parent or one of its subsidiaries, then, and in each
     such case, the agreement governing such transaction shall make proper
     provision so that the Option shall, upon the consummation of any such
     transaction and upon the terms and conditions set forth herein, be
     converted into, or exchanged for, an option with identical terms
     appropriately adjusted to acquire the number and class of shares or other
     securities or property that Parent would have received in respect of
     Company Common Stock if the Option had been exercised immediately prior to
     such consolidation, merger, sale or transfer, or the record date therefor,
     as applicable.

                                      -9-
<PAGE>
 
(c)  If, prior to the termination of the Option in accordance with Section 2 or
     the Notice Date, the Company enters into any agreement pursuant to which
     all outstanding shares of Company Common Stock are to be purchased for, or
     converted into the right to receive in whole or in part (other than in
     respect of fractional shares), cash (a "Transaction"), the Company
     covenants that proper provision shall be made in such agreement to provide
     that, if the Option shall not therefore have been exercised, then upon the
     consummation of a Transaction (which in the case of a Transaction involving
     a tender offer shall be when shares of Company Common Stock are accepted
     for payment), Parent shall receive in exchange for the cancellation of the
     Option an amount in cash equal to the Cash Consideration and if proper
     provision is so made the Option shall be cancelled.  For purposes of this
     Agreement, the term "Cash Consideration" means the number of Option Shares
     multiplied by the difference between (A) the closing market price per share
     of Company Common Stock on the day immediately prior to the consummation of
     a Transaction and (B) the Purchase Price.

(d)  Whenever the number of Option Shares purchasable upon exercise hereof is
     adjusted as provided in this Section 9, the Purchase Price shall be
     adjusted by multiplying the Purchase Price by a fraction, the numerator of
     which shall be equal to the number of shares of Company Common Stock
     purchasable prior to the adjustment and the denominator of which shall be
     equal to the number of shares of Company Common Stock purchasable after the
     adjustment.

10.  Exchange Loss or Mutilation.  This Agreement (and the Option granted
     ---------------------------                                         
hereby) are exchangeable, without expense, at the option of the Parent, upon
presentation and surrender of this Agreement at the principal office of the
Company, for other agreements providing for Options of different denominations
entitling the Parent to purchase, on the same terms and subject to the same
conditions as are set forth herein, in the aggregate the same number of Option
Shares hereunder.  The terms "Stock Option Agreement" and "Option" as used
herein include any Stock Option Agreements and related options for which this
Agreement (and the Option granted hereby) may be exchanged.  Upon receipt by the
Company of evidence reasonably satisfactory to it of the loss, theft,
destruction or mutilation of this Agreement, and (in the case of loss, theft or
destruction) of reasonably satisfactory indemnification, and upon surrender and
cancellation of this Agreement, if mutilated, the Company shall execute and
deliver a new Agreement of like tenor and date.  Any such new Agreement executed
and delivered shall constitute an additional contractual obligation on the part
of the Company, whether or not the Agreement so lost, stolen, destroyed or
mutilated shall at any time be enforceable by anyone.

11.  Certain Covenants of the Company.  The Company agrees:  (i) that it shall
     --------------------------------                                         
at all times maintain, free from preemptive rights, sufficient authorized but
unissued or treasury shares of Common Stock so that the Option may be exercised
without additional authorization of Common Stock after giving effect to all
other options, warrants, convertible securities and other rights to purchase
Company Common Stock; (ii) that it will not, by charter amendment or through
reorganization, consolidation, merger, dissolution or sale of assets, or by any
other voluntary act, avoid or seek to avoid the observance or performance of any
of the covenants, stipulations or conditions to be observed or performed
hereunder by the Company; (iii) promptly to take all action as may from time to
time be required (including complying with all premerger

                                      -10-
<PAGE>
 
notification, reporting and waiting period requirements specified in 15 U.S.C.
Section 18a and regulations promulgated thereunder or to any other governmental
entity is necessary before the Option may be exercised, cooperating fully with
the Parent in preparing such applications or notices and providing such
information to each such governmental entity as they may require) in order to
permit the Parent to exercise the Option and the Company duly and effectively to
issue Option Shares pursuant hereto; and (iv) to take all action provided herein
to protect the rights of the Parent against dilution.

12.  Specific Performance.  The Company acknowledges that if the Company fails
     --------------------                                                     
to perform any of its obligations under this Agreement immediate and irreparable
harm or injury would be caused to Parent for which money damages would not be an
adequate remedy.  In such event, the Company agrees that Parent shall have the
right, in addition to any other rights it may have, to specific performance of
this Agreement.

13.  Profit Limitation.  (a) Notwithstanding any other provision of this
     -----------------                                                  
Agreement, in no event shall Parent's Total Profit (as hereinafter defined)
exceed $24 million (the "Cap") and, if it otherwise would exceed such amount,
Parent, at its sole election, shall either (a) deliver to the Company for
cancellation Shares previously purchased by Parent (valued at the average of the
last sales price for Company Common Stock for the ten trading days ending on the
day immediately preceding such delivery), (b) pay cash to the Company or (c)
undertake any combination thereof, so that Parent's Total Profit shall not
exceed the Cap after taking into account the foregoing actions.

          As used herein, the term "Total Profit" shall mean the aggregate
amount (before taxes) of the following: (i) the amount of cash paid or payable
by Parent pursuant to Section 7.1(b) of the Merger Agreement, (ii) (x) the
amount paid or payable by Parent pursuant to the Company's repurchase of Option
Shares pursuant to Section 7 hereof, less (y) Parent's purchase price for such
Option Shares, and (iii) (x) the net cash amounts received by Parent pursuant to
the sale of Option Shares (or any other securities into which such Option Shares
are converted or exchanged) to any unaffiliated party, less (y) Parent's
purchase price for such Option Shares.

14.  Miscellaneous.
     ------------- 

(a)  Expenses.  Except as otherwise provided in the Sections 6 and 7, each of
     --------                                                                
     the parties hereto shall bear and pay all costs and expenses incurred by it
     or on its behalf in connection with the transactions contemplated
     hereunder, including fees and expenses of its own financial consultants,
     investment bankers, accountants and counsel.

(b)  Waiver and Amendment.  Any provision of this Agreement may be waived at any
     --------------------                                                       
     time by the party that is entitled to the benefits of such provision, but
     such waiver shall only be effective if in writing and signed by the party
     entitled to the benefits of such provision.  This Agreement may not be
     amended, except by an instrument in writing signed on behalf of each of the
     parties.  The failure of any party to this Agreement to assert any of its
     rights under this Agreement or otherwise shall not constitute a waiver of
     such rights.

                                      -11-
<PAGE>
 
(c)  Descriptive Headings.  The descriptive headings contained herein are for
     --------------------                                                    
     convenience of reference only and shall not affect in any way the meaning
     or interpretation of this Agreement.

(d)  Entire Agreement; No Third-Party Beneficiaries.  Except as otherwise
     ----------------------------------------------                      
     provided, in this Agreement, the Merger Agreement (including the documents
     and instruments referred to therein), the Confidentiality Agreement by and
     between the Company and Parent, dated May 27, 1998, the Supplement to the
     Confidentiality Agreement by and between the Company and Parent, dated May
     6, 1998 and that certain Reciprocal Confidentiality Agreement by and
     between the Company and Parent (i) constitute the entire agreement, and
     supersede all prior agreements and understandings, both written and oral,
     between the parties with respect to the subject matter of this Agreement,
     and (ii) not intended to confer upon any person other than the parties any
     rights or remedies.  If any term, provision, covenant, or restriction of
     this Agreement is held by a court of competent jurisdiction or a federal or
     state regulatory agency to be invalid, void, or unenforceable, the other
     terms, provisions, covenants, and restrictions of this Agreement shall
     remain in full force and effect and shall not be affected, impaired, or
     invalidated.  If for any reason such court or regulatory agency determines
     that the Option does not permit Parent to acquire, or does not require the
     Company to repurchase, the full number of Option Shares provided herein (as
     adjusted pursuant to Section 9), it is the express intention of the Company
     to allow Parent to acquire, or to require the Company to repurchase, such
     lesser number of shares as may be permissible without any amendment or
     modification hereof.

(e)  GOVERNING LAW.  This Agreement shall be governed by and construed in
     -------------                                                       
     accordance with the laws of the State of Delaware (regardless of the laws
     that might otherwise govern under applicable Delaware principles of
     conflicts of law).  Each of the parties hereto waives any right to trial by
     jury with respect to any claim or proceeding related to or arising out of
     this Agreement or any of the transactions contemplated hereby.  THE GRANTOR
     AGREES THAT, IN CONNECTION WITH ANY LEGAL SUIT OR PROCEEDING ARISING WITH
     RESPECT TO THIS AGREEMENT, IT SHALL SUBMIT TO THE JURISDICTION OF THE
     UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE AND AGREES TO
     VENUE IN SUCH COURTS.  THE GRANTOR HEREBY APPOINTS THE SECRETARY OF THE
     GRANTOR AS ITS AGENT FOR SERVICE OF PROCESS FOR PURPOSES OF THE FOREGOING
     SENTENCE ONLY.

(f)  Notices.  All notices, requests, claims, demands and other communications
     -------                                                                  
     under this Agreement must be in writing and shall be deemed given if
     delivered personally, telecopied (which is confirmed) or sent by overnight
     courier (providing proof of delivery) to the parties at the following
     addresses (or at such other address for a party as shall be specified by
     like notice):

                                      -12-
<PAGE>
 
          (i)  if to Company, to:


               Penederm Incorporated
               320 Lakeside Drive
               Foster City, California 94404


               Telecopy No.:  (650) 358-0547


               Attention:  Lloyd H. Malchow
                           President & Chief Executive Officer

               with copies to:


               Heller Ehrman White & McAuliffe
               525 University Avenue
               Palo Alto, CA  94301-1300


               Telecopy No.:  (650) 324-0638


               Attention:  Henry Lesser; and

          (ii) if to Parent, to:


               Mylan Laboratories Inc.
               781 Chestnut Ridge Road
               P.O. Box 4310
               Morgantown, WV  26505


               Telecopy No.:  (304) 599-7284


               Attention:  Roderick P. Jackson
                           Senior Vice President

               with a copy to:


               Buchanan Ingersoll Professional Corporation
               One Oxford Centre
               301 Grant Street, 20th Floor
               Pittsburgh, PA  15219-1420


               Telecopy No.:  (412) 562-1041


               Attention:  JoEllen Lyons/John R. Previs

                                      -13-
<PAGE>
 
(g)  Counterparts.  This Agreement and any amendments hereto may be executed in
     ------------                                                              
     two counterparts, each of which shall be considered one and the same
     agreement and shall become effective when both counterparts have been
     signed by each of the parties and delivered to the other party, it being
     understood that both parties need not sign the same counterparts.

(h)  Assignment.  Neither this Agreement nor any of the rights, interests or
     ----------                                                             
     obligations hereunder or under the Option shall be assigned by any of the
     parties hereto (whether by operation of law or otherwise) without the prior
     written consent of the other party except that Parent may assign this
     Agreement and its rights hereunder to any of its subsidiaries.  Subject to
     the preceding sentence, this Agreement shall be binding upon, inure to the
     benefit of and be enforceable by the parties and their respective
     successors and assigns.

(i)  Further Assurances.  In the event of any exercise of the Option by Parent,
     ------------------                                                        
     the Company and Parent shall execute and deliver all other documents and
     instruments and take all other actions that may be reasonably necessary in
     order to consummate the transactions provided for by such exercise.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
signed by their respective officers thereunto duly authorized as of the day and
year first written above.

                              PENEDERM INCORPORATED



                              By: /s/ Lloyd H. Malchow
                                  -----------------------------------
                                  Lloyd H. Malchow
                                  President and Chief Executive Officer


                              MYLAN LABORATORIES INC.



                              By: /s/ Roderick P. Jackson
                                  -----------------------------------
                                  Roderick P. Jackson
                                  Senior Vice President

                                      -14-

<PAGE>
                                                                    Exhibit 99.2


                                VOTING AGREEMENT

          VOTING AGREEMENT, dated as of June 24, 1998, between Mylan
Laboratories Inc., a Pennsylvania corporation ("Parent"), and the persons listed
on Schedule A hereto (individually, a "Stockholder" and collectively, the
"Stockholders").

          WHEREAS, Parent and Penederm Incorporated, a Delaware corporation (the
"Company"), propose to enter into an Agreement and Plan of Merger, dated the
date hereof (as the same may be amended or supplemented, the "Merger Agreement")
providing for the merger of MLI Acquisition Corp., a Delaware corporation and
wholly-owned subsidiary of Parent ("Subsidiary"), with the Company (the
"Merger");

          WHEREAS, each Stockholder is the record and beneficial owner of the
number of shares of common stock, par value $.01 per share, of the Company (the
"Company Common Stock") set forth opposite such Stockholder's name on Schedule A
hereto; such securities, as they may be adjusted by stock dividend, stock split,
recapitalization, combination or exchange of shares, merger, consolidation,
reorganization or other change or transaction of or by the Company, together
with securities that may be acquired after the date hereof by such Stockholder,
including Company Common Stock issuable upon the exercise of options to purchase
Company Common Stock (as the same may be adjusted as aforesaid), being
collectively referred to herein as the "Securities"; and

          WHEREAS, as a condition to their willingness to enter into the Merger
Agreement, Parent and Subsidiary have requested that the Stockholders enter into
this Agreement (capitalized terms not otherwise defined herein shall have the
meanings set forth in the Merger Agreement);

          NOW, THEREFORE, to induce Parent and Subsidiary to enter into, and in
consideration of them entering into, the Merger Agreement, and in consideration
of the premises and the representations, warranties and agreements contained
herein and intending to be legally bound hereby, the parties hereby agree as
follows:

1.  COVENANTS OF THE STOCKHOLDERS.  Each Stockholder, severally and not jointly,
agrees as follows:

(a)  Each Stockholder shall not, except as contemplated by the terms of this
     Agreement, (i) sell, transfer, pledge, assign or otherwise dispose of, or
     enter into any agreement, option or other arrangement (including any profit
     sharing arrangement) or understanding with respect to the sale, transfer,
     pledge, assignment or other disposition of, the Securities to any person
     other than Parent or Parent's designee, (ii) enter into any voting
     arrangement, whether by proxy, voting agreement, voting trust, power-of-
     attorney or otherwise, with respect to the Securities or (iii) take any
     other action that would in any way restrict, limit or interfere with the
     performance of its obligations hereunder or the transactions contemplated
<PAGE>
 
     hereby; provided, however, that any Stockholder that is an individual may
     transfer all or any part of his or her Securities to any sibling or any
     other member of his or her immediate family, any of his or her lineal
     descendants or any trust for the benefit of any of them, if the recipient
     of the Securities agrees in advance in writing delivered to Parent to be
     bound by this Agreement.

(b)  Until the Merger is consummated or the Merger Agreement is terminated, the
     Stockholder shall not, nor shall the Stockholder permit any investment
     banker, financial adviser, attorney, accountant or other representative or
     agent acting on behalf of or at the direction of the Stockholder (a
     "Stockholder Representative") to, directly or indirectly (i) solicit,
     initiate or encourage (including by way of furnishing information), or take
     any other action designed or reasonably likely to facilitate, any inquiries
     or the making of any proposal which constitutes, or may reasonably be
     expected to lead to, any Takeover Proposal (as defined in the Merger
     Agreement) or (ii) participate in any discussions or negotiations regarding
     any Takeover Proposal. Without limiting the foregoing, it is understood
     that any violation of the restrictions set forth in the preceding sentence
     by a Stockholder Representative shall be deemed to be a violation of this
     Section 1(b) by the Stockholder.

(c)  At any meeting of stockholders of the Company called to vote upon the
     Merger and the Merger Agreement or at any adjournment thereof or in any
     other circumstances upon which a vote, consent or other approval (including
     by written consent) with respect to the Merger and the Merger Agreement is
     sought from the stockholders of the Company, each Stockholder shall,
     including by initiating a written consent solicitation if requested by
     Parent, vote (or cause to be voted) such Stockholder's Securities in favor
     of approving the Merger, the adoption of the Merger Agreement and the
     approval of the other transactions contemplated by the Merger Agreement and
     the calling of a special meeting of the stockholders of the Company to
     consider any of the foregoing.  At any meeting of stockholders of the
     Company or at any adjournment thereof or in any other circumstances upon
     which the Stockholder's vote, consent or other approval is sought, such
     Stockholder shall vote (or cause to be voted) such Stockholder's Securities
     against (i) any merger agreement or merger (other than the Merger Agreement
     and the Merger), consolidation, combination, sale or license of substantial
     assets, reorganization, recapitalization, dissolution, liquidation or
     winding up of or by the Company or any other Takeover Proposal (as defined
     in the Merger Agreement) (collectively, "Alternative Transactions"), or
     (ii) any amendment of the Company's Certificate of Incorporation or by-laws
     or other proposal or transaction involving the Company or any of its
     subsidiaries or any motion at a meeting of stockholders of the Company,
     which amendment or other proposal or transaction or motion would in any
     manner impede, frustrate, prevent or nullify, the Merger, the Merger
     Agreement or any of the other transactions contemplated by the Merger
     Agreement including any consent to the treatment of any Securities in or in
     connection with such transaction (collectively, "Frustrating
     Transactions").

2.   GRANT OF IRREVOCABLE PROXY COUPLED WITH AN INTEREST; APPOINTMENT OF PROXY.

(a)  Each Stockholder hereby irrevocably grants to, and appoints, any individual
     who shall be designated by Parent, and each of them, such Stockholder's
     proxy and

                                      -2-
<PAGE>
 
     attorney-in-fact (with full power of substitution), for and in the name,
     place and stead of such Stockholder, to vote such Stockholder's Securities,
     or grant a consent or approval in respect of such Securities, at any
     meeting of stockholders of the Company or at any adjournment thereof or in
     any other circumstances upon which their vote, consent or other approval is
     sought, (i) in favor of the Merger, the adoption by the Company of the
     Merger Agreement and the approval of the other transactions contemplated by
     the Merger Agreement and the calling of a special meeting of the
     stockholders of the Company to consider any of the foregoing, and (ii)
     against any Alternative Transaction or Frustrating Transaction.

(b)  Each Stockholder represents that any proxies heretofore given in respect of
     such Stockholder's Securities are not irrevocable, and that any such
     proxies are hereby revoked.

(c)  EACH STOCKHOLDER HEREBY AFFIRMS THAT THE PROXY SET FORTH IN THIS SECTION 2
     IS COUPLED WITH AN INTEREST AND IS IRREVOCABLE UNTIL SUCH TIME AS THIS
     AGREEMENT TERMINATES IN ACCORDANCE WITH ITS TERMS.  Such Stockholder hereby
     further affirms that such irrevocable proxy is given in connection with the
     execution of the Merger Agreement, and that such irrevocable proxy is given
     to secure the performance of the duties of such Stockholder under this
     Agreement.  Such Stockholder hereby ratifies and confirms all that the
     individual voting such irrevocable proxy may lawfully do or cause to be
     done by virtue hereof.  Such irrevocable proxy is executed and intended to
     be irrevocable in accordance with the provisions of Section 212 of the
     DGCL.  Such irrevocable proxy shall be valid until the later to occur of
     (i) one year from the date hereof or (ii) the termination of this Agreement
     in accordance with its terms.

3.  REPRESENTATIONS AND WARRANTIES OF THE STOCKHOLDERS.  Each Stockholder
hereby, severally and not jointly, represents and warrants to Parent as follows:

(a)  AUTHORIZATION.  The Stockholder has the legal capacity to execute, deliver
     and perform this Agreement.  This Agreement constitutes a valid and binding
     obligation of the Stockholder enforceable against the Stockholder in
     accordance with its terms.  If the Stockholder is married and the
     Securities constitute community property under applicable law, this
     Agreement has been duly authorized, executed and delivered by, and
     constitutes the valid and binding agreement of, the Stockholder's spouse
     enforceable against such spouse in accordance with its terms.

(b)  NO CONFLICT.  The execution, delivery and performance by the Stockholder of
     this Agreement and the consummation of the transactions contemplated hereby
     do not and will not (i) result in any breach or violation of or be in
     conflict with or constitute a default under any law or agreement or
     arrangement to which the Stockholder is a party or by which the Stockholder
     is bound, (ii) require any filing with or authorization by any governmental
     entity or (iii) require any consent or other action by any person under,
     constitute a default under, or give rise to any right of termination,
     cancellation or acceleration of a loss of any benefit to

                                      -3-
<PAGE>
 
     which the Stockholder is entitled under any provision of any agreement or
     other instrument binding on the Stockholder.

(c)  OWNERSHIP OF SECURITIES.  Each Stockholder's Securities and the
     certificates representing such Securities are now, and at all times during
     the term hereof will be, held by each Stockholder, or by a nominee or
     custodian for the benefit of such Stockholder, and the Stockholder has good
     and marketable title to such Securities, free and clear of any (i) liens,
     proxies, voting trusts or agreements, understandings or arrangements and
     (ii) pledges, restrictions, charges or other adverse claims of any kind or
     nature.  Each Stockholder owns of record or beneficially no securities of
     the Company, or any options, warrants or rights exercisable for securities
     of the Company, other than the Securities set forth opposite the
     Stockholder's name on Schedule A hereto.

(d)  MERGER AGREEMENT.  Each Stockholder understands and acknowledges that
     Parent and Subsidiary are entering into the Merger Agreement in reliance
     upon the Stockholder's execution and delivery of this Agreement.

4.  FURTHER ASSURANCES.  Each Stockholder will, from time to time, execute and
deliver, or cause to be executed and delivered, such additional or further
transfers, assignments, endorsements, consents and other instruments as Parent
may reasonably request for the purpose of effectively carrying out the
transactions contemplated by this Agreement and to vest the power to vote such
Stockholder's Securities as contemplated by Section 2.

5.  ASSIGNMENT; BINDING EFFECT.  Neither this Agreement nor any of the rights,
interests or obligations hereunder shall be assigned by any of the parties
hereto (whether by operation of law or otherwise) without the prior written
consent of the other parties.  Subject to the preceding sentence, this Agreement
shall be binding upon, inure to the benefit of, and be enforceable by, the
parties hereto and their respective successors and assigns.  Notwithstanding
anything contained in this Agreement to the contrary, nothing in this Agreement,
expressed or implied, is intended to confer on any person other than the parties
hereto or their respective heirs, successors, executors, administrators and
assigns any rights, remedies, obligations or liabilities under or by reason of
this Agreement.

6.  TERMINATION.  This Agreement, and all rights and obligations of the parties
hereunder, shall terminate upon the earliest to occur of the Effective Time or
the  termination of the Merger Agreement in accordance with its terms.  Nothing
in this Section 6 shall relieve any party from liability for willful breach of
this Agreement.

7.  STOP TRANSFER.  The Company agrees with, and covenants to, Parent that the
Company shall not register the transfer of any certificate representing any
Stockholder's Securities unless such transfer is made in accordance with the
terms of this Agreement.

8.  GENERAL PROVISIONS.

(a)  EXPENSES.  All costs and expenses incurred by Parent in connection with
     this Agreement and the transactions contemplated hereby shall be paid by

                                      -4-
<PAGE>
 
     Parent.  All costs and expenses incurred by the Stockholders in connection
     with this Agreement and the transactions contemplated hereby shall be paid
     by the Company.

(b)  AMENDMENTS.  This Agreement may not be amended except by an instrument in
     writing signed by each of the parties hereto.

(c)  NOTICE.  All notices and other communications hereunder shall be in writing
     and shall be deemed given upon receipt to the parties at the following
     addresses (or at such other address for a party as shall be specified by
     like notice):

                       (i)  if to Parent, to:

                            Mylan Laboratories Inc.
                            781 Chestnut Ridge Road
                             Post Office Box 4310
                             Morgantown, WV  26505
                        Telecopy Number (304) 599-7284

                                with a copy to:

                            John R. Previs, Esquire
                  Buchanan Ingersoll Professional Corporation
                               One Oxford Centre
                         301 Grant Street, 20th Floor
                          Pittsburgh, PA  15219-1410
                        Telecopy Number (412) 562-1041

and

                      (ii) if to a Stockholder, to the address set forth under 
the name of such Stockholder on Schedule A hereto:

                                with a copy to:

                             Henry Lesser, Esquire
                        Heller Ehrman White & McAuliffe
                             525 University Avenue
                           Palo Alto, CA  94301-1300
                        Telecopy Number (650) 324-0638

(d)  INTERPRETATION.  When a reference is made in this Agreement to a Section,
     such reference shall be to a Section of this Agreement unless otherwise
     indicated.  The headings contained in this Agreement are for reference
     purposes only and shall not affect in any way the meaning or interpretation
     of this Agreement.  Wherever the words "include", "includes" or "including"
     are used in this Agreement, they shall be deemed to be followed by the
     words "without limitation".

                                      -5-
<PAGE>
 
(e)  COUNTERPARTS.  This Agreement may be executed in two or more counterparts,
     all of which shall be considered one and the same agreement and shall
     become effective when two or more counterparts have been signed by each of
     the parties and delivered to the other parties, it being understood that
     all parties need not sign the same counterpart.

(f)  ENTIRE AGREEMENT; NO THIRD-PARTY BENEFICIARIES. This Agreement (including
     the documents and instruments referred to herein) (i) constitutes the
     entire agreement and supersedes all prior agreements and understandings,
     both written and oral, among the parties with respect to the subject matter
     hereof and (ii) is not intended to confer upon any person other than the
     parties hereto any rights or remedies hereunder.

(g)  GOVERNING LAW.  This Agreement shall be governed and construed in
     accordance with the laws of the State of Delaware without regard to any
     applicable conflicts of law.

9.  STOCKHOLDER CAPACITY.  As of the date of this Agreement, each of the
Stockholders is a director of the Company.  None of the Stockholders makes any
agreement or understanding herein in his or her capacity as a director or
officer of the Company.  Each Stockholder signs solely in his or her capacity as
the record holder and beneficial owner of, or the trustee of a trust whose
beneficiaries are the beneficial owners of, such Stockholder's Securities and
nothing herein shall limit or affect any actions taken by a Stockholder in his
or her capacity as an officer or director of the Company to the extent
specifically permitted by the Merger Agreement.

10.  ENFORCEMENT.  The parties agree that irreparable damage would occur in the
event that any of the provisions of this Agreement were not performed in
accordance with their specific terms or were otherwise breached.  It is
accordingly agreed that the parties shall be entitled to an injunction or
injunctions to prevent breaches of this Agreement and to enforce specifically
the terms and provisions of this Agreement in a court of the United States.
This being in addition to any other remedy to which they are entitled at law or
in equity.  In addition, each of the parties hereto waives any right to trial by
jury with respect to any claim or proceeding related to or arising out of this
Agreement or any of the transactions contemplated hereby.

EACH STOCKHOLDER AGREES THAT, IN CONNECTION WITH ANY LEGAL SUIT OR PROCEEDING
ARISING WITH RESPECT TO THIS AGREEMENT, IT SHALL SUBMIT TO THE JURISDICTION OF
THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE AND AGREES TO
VENUE IN SUCH COURTS.  EACH STOCKHOLDER HEREBY APPOINTS THE SECRETARY OF THE
COMPANY AS HIS OR HER  AGENT FOR SERVICE OF PROCESS FOR PURPOSES OF THE
FOREGOING SENTENCE ONLY.  EACH PARTY HERETO WAIVES ANY RIGHT TO JURY TRIAL IN
CONNECTION WITH ANY SUCH SUIT OR PROCEEDING.

                                      -6-
<PAGE>
 
          IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                    MYLAN LABORATORIES INC.


                                    By:    /s/ Roderick P. Jackson
                                        -------------------------------------
                                    Name:  Roderick P. Jackson
                                    Title: Senior Vice President

                                    STOCKHOLDERS

                                    
                                    /s/ Gerald Weinstein
                                    ----------------------------------
                                    Gerald Weinstein


                                    /s/ Marcia Weinstein
                                    ----------------------------------
                                    Marcia Weinstein


                                    /s/ David Collins
                                    ----------------------------------
                                    David Collins


                                    /s/ Harvey S. Sadow
                                    ----------------------------------
                                    Dr. Harvey S. Sadow, Ph.D.


                                    /s/Lloyd Malchow 
                                    ----------------------------------
                                    Lloyd Malchow


                                    /s/ Robert F. Allnutt
                                    ----------------------------------
                                    Robert F. Allnutt


                                    /s/ William E. Bergman
                                    ----------------------------------
                                    William E. Bergman


                                    /s/ Joseph E. Smith
                                    ----------------------------------
                                    Joseph E. Smith

                                      -7-
<PAGE>
 
                                   SCHEDULE A
                                   ----------

<TABLE>
<CAPTION>

STOCKHOLDER                                                          SECURITIES HELD
- ---------------------------------------------------------  ------------------------------------
<S>                                                        <C>
Gerald and Marcia Weinstein                                               27,725
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
 
David Collins                                                             15,000
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
 
Dr. Harvey S. Sadow, Ph.D.                                                10,000
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
 
Lloyd Malchow                                                              7,840
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
 
Robert F. Allnutt                                                          1,000
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
 
William E. Bergman                                                             0
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
 
Joseph E. Smith                                                                0
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
</TABLE>

                                      -8-

<PAGE>
                                                                    Exhibit 99.3


 
                          ALTERNATE VOTING AGREEMENT

          VOTING AGREEMENT, dated as of June 24, 1998, between Mylan
Laboratories Inc., a Pennsylvania corporation ("Parent"), and Mark J.
Gabrielson, individually and in his capacity as the general partner of Prince
Ventures L.P. ("Ventures"), the general partner of Prince Venture Partners III,
L.P. (the "Stockholder").

          WHEREAS, Parent and Penederm Incorporated, a Delaware corporation (the
"Company"), propose to enter into an Agreement and Plan of Merger, dated the
date hereof (as the same may be amended or supplemented, the "Merger Agreement")
providing for the merger of MLI Acquisition Corp., a Delaware corporation and
wholly-owned subsidiary of Parent ("Subsidiary"), with the Company (the
"Merger");

          WHEREAS, the  Stockholder is the beneficial owner of the number of
shares of common stock, par value $.01 per share, of the Company (the "Company
Common Stock") set forth on Schedule A hereto; such securities, as they may be
adjusted by stock dividend, stock split, recapitalization, combination or
exchange of shares, merger, consolidation, reorganization or other change or
transaction of or by the Company, together with securities that may be acquired
after the date hereof by the Stockholders, including Company Common Stock
issuable upon the exercise of options to purchase Company Common Stock (as the
same may be adjusted as aforesaid), being collectively referred to herein as the
"Securities"; and

          WHEREAS, as a condition to their willingness to enter into the Merger
Agreement, Parent and Subsidiary have requested that the Stockholder enter into
this Agreement (capitalized terms not otherwise defined herein shall have the
meanings set forth in the Merger Agreement);

          NOW, THEREFORE, to induce Parent and Subsidiary to enter into, and in
consideration of them entering into, the Merger Agreement, and in consideration
of the premises and the representations, warranties and agreements contained
herein and intending to be legally bound hereby, the parties hereby agree as
follows:

1.  COVENANTS OF THE STOCKHOLDER.  Stockholder agrees as follows:

(a)  Except as contemplated by the terms of this Agreement (including, without
     limitation to Section 1(d)), Stockholder shall not, (i) sell, transfer,
     pledge, assign or otherwise dispose of, or enter into any agreement, option
     or other arrangement (including any profit sharing arrangement) or
     understanding with respect to the sale, transfer, pledge, assignment or
     other disposition of, the Securities to any person other than Parent or
     Parent's designee, (ii) enter into any voting arrangement, whether by
     proxy, voting agreement, voting trust, power-of-attorney or otherwise, with
     respect to the Securities or (iii) take any other action that would in any
     way restrict, limit or interfere with the performance of its obligations
     hereunder or the transactions contemplated hereby; provided, however, that
     the Stockholder may transfer all or any part of his Securities to any
     sibling or any other member of his immediate family, any of
<PAGE>
 
     his lineal descendants or any trust for the benefit of any of them, if the
     recipient of the Securities agrees in advance in writing delivered to
     Parent to be bound by this Agreement.

(b)  Until the Merger is consummated or the Merger Agreement is terminated, the
     Stockholder shall not, nor shall the Stockholder permit any investment
     banker, financial adviser, attorney, accountant or other representative or
     agent acting on behalf of or at the direction of the Stockholder (a
     "Stockholder Representative") to, directly or indirectly (i) solicit,
     initiate or encourage (including by way of furnishing information), or take
     any other action designed or reasonably likely to facilitate, any inquiries
     or the making of any proposal which constitutes, or may reasonably be
     expected to lead to, any Takeover Proposal (as defined in the Merger
     Agreement) or (ii) participate in any discussions or negotiations regarding
     any Takeover Proposal. Without limiting the foregoing, it is understood
     that any violation of the restrictions set forth in the preceding sentence
     by a Stockholder Representative shall be deemed to be a violation of this
     Section 1(b) by the Stockholder.

(c)  At any meeting of stockholders of the Company called to vote upon the
     Merger and the Merger Agreement or at any adjournment thereof or in any
     other circumstances upon which a vote, consent or other approval (including
     by written consent) with respect to the Merger and the Merger Agreement is
     sought from the stockholders of the Company, Stockholder shall, including
     by initiating a written consent solicitation if requested by Parent, vote
     (or cause to be voted) such Stockholder's Securities in favor of approving
     the Merger, the adoption of the Merger Agreement and the approval of the
     other transactions contemplated by the Merger Agreement and the calling of
     a special meeting of the stockholders of the Company to consider any of the
     foregoing.  At any meeting of stockholders of the Company or at any
     adjournment thereof or in any other circumstances upon which Stockholder's
     vote, consent or other approval is sought, Stockholder shall vote (or cause
     to be voted) Stockholder's Securities against (i) any merger agreement or
     merger (other than the Merger Agreement and the Merger), consolidation,
     combination, sale or license of substantial assets, reorganization,
     recapitalization, dissolution, liquidation or winding up of or by the
     Company or any other Takeover Proposal (as defined in the Merger Agreement)
     (collectively, "Alternative Transactions"), or (ii) any amendment of the
     Company's Certificate of Incorporation or by-laws or other proposal or
     transaction involving the Company or any of its subsidiaries or any motion
     at a meeting of stockholders of the Company, which amendment or other
     proposal or transaction or motion would in any manner impede, frustrate,
     prevent or nullify, the Merger, the Merger Agreement or any of the other
     transactions contemplated by the Merger Agreement including any consent to
     the treatment of any Securities in or in connection with such transaction
     (collectively, "Frustrating Transactions").

(d)  Notwithstanding Sections 1(a) and (c), Parent and Subsidiary in reliance
     upon Stockholder's representations and warranties contained in Section
     3(e), agree that:  (i) Stockholder may cause the Distribution (as defined
     in Section 3(e)) to be made; and (ii) upon the effective date of the
     Distribution (or such earlier date, if any, as any Securities are required
     to be distributed in the event of an amendment of the Prince Partnership
     Agreement), Stockholder shall cease to be bound by Section 1(c), and the
     irrevocable proxy granted by Section 2 shall terminate, with respect to any
     vote or consent that has not yet occurred (whether or not the applicable

                                      -2-
<PAGE>
 
     record date has passed) and each Distributee (as defined in Section 3(e))
     shall be free to vote or consent as such Distributee chooses; provided,
                                                                   -------- 
     however, that Stockholder shall continue to be bound by all provisions of
     -------                                                                  
     this Agreement with respect to any other Securities over which he retains
     the power to vote after the effective date of the Distribution.

2.   GRANT OF IRREVOCABLE PROXY COUPLED WITH AN INTEREST; APPOINTMENT OF PROXY.

(a)  Stockholder hereby irrevocably grants to, and appoints, any individual who
     shall be designated by Parent, and each of them, Stockholder's proxy and
     attorney-in-fact (with full power of substitution), for and in the name,
     place and stead of Stockholder, to vote Stockholder's Securities, or grant
     a consent or approval in respect of such Securities, at any meeting of
     stockholders of the Company or at any adjournment thereof or in any other
     circumstances upon which their vote, consent or other approval is sought,
     (i) in favor of the Merger, the adoption by the Company of the Merger
     Agreement and the approval of the other transactions contemplated by the
     Merger Agreement and the calling of a special meeting of the stockholders
     of the Company to consider any of the foregoing, and (ii) against any
     Alternative Transaction or Frustrating Transaction.

(b)  Stockholder represents that any proxies heretofore given in respect of
     Stockholder's Securities are not irrevocable, and that any such proxies are
     hereby revoked.

(c)  STOCKHOLDER HEREBY AFFIRMS THAT THE PROXY SET FORTH IN THIS SECTION 2 IS
     COUPLED WITH AN INTEREST AND IS IRREVOCABLE UNTIL SUCH TIME AS THIS
     AGREEMENT OR SUCH PROXY TERMINATES IN ACCORDANCE WITH ITS TERMS.
     Stockholder hereby further affirms that such irrevocable proxy is given in
     connection with the execution of the Merger Agreement, and that such
     irrevocable proxy is given to secure the performance of the duties of
     Stockholder under this Agreement.  Stockholder hereby ratifies and confirms
     all that the individual voting such irrevocable proxy may lawfully do or
     cause to be done by virtue hereof.  Such irrevocable proxy is executed and
     intended to be irrevocable in accordance with the provisions of Section 212
     of the DGCL.  Such irrevocable proxy shall be valid until the later to
     occur of (i) one year from the date hereof or (ii) the termination of this
     Agreement in accordance with its terms.

3.  REPRESENTATIONS AND WARRANTIES OF STOCKHOLDER.  Stockholder hereby,
severally and not jointly, represents and warrants to Parent as follows:

(a)  AUTHORIZATION.  The Stockholder has the legal capacity to execute, deliver
     and perform this Agreement.  This Agreement constitutes a valid and binding
     obligation of the Stockholder enforceable against the Stockholder in
     accordance with its terms.  If the Stockholder is married and the
     Securities constitute community property under applicable law, this
     Agreement has been duly authorized, executed and delivered by, and
     constitutes the valid and binding agreement of, the Stockholder's spouse
     enforceable against such spouse in accordance with its terms.

                                      -3-
<PAGE>
 
(b)  NO CONFLICT.  The execution, delivery and performance by the Stockholder of
     this Agreement and the consummation of the transactions contemplated hereby
     do not and will not (i) result in any breach or violation of or be in
     conflict with or constitute a default under any law or agreement or
     arrangement to which the Stockholder is a party or by which the Stockholder
     is bound, (ii) require any filing with or authorization by any governmental
     entity or (iii) require any consent or other action by any person under,
     constitute a default under, or give rise to any right of termination,
     cancellation or acceleration of a loss of any benefit to which the
     Stockholder is entitled under any provision of any agreement or other
     instrument binding on the Stockholder.

(c)  OWNERSHIP OF SECURITIES.  Stockholder's Securities and the certificates
     representing such Securities are now, and at all times during the term
     hereof will be, held by Stockholder, or by a nominee or custodian for the
     benefit of Stockholder, and Stockholder has good and marketable title to
     such Securities, free and clear of any (i) liens, proxies, voting trusts or
     agreements, understandings or arrangements and (ii) pledges, restrictions,
     charges or other adverse claims of any kind or nature, except as described
     in Section 3(e).  Stockholder owns of record or beneficially no securities
     of the Company, or any options, warrants or rights exercisable for
     securities of the Company, other than the Securities set forth opposite the
     Stockholder's name on Schedule A hereto.

(d)  MERGER AGREEMENT.  Stockholder understands and acknowledges that Parent and
     Subsidiary are entering into the Merger Agreement in reliance upon the
     Stockholder's execution and delivery of this Agreement.

(e)  OTHER MATTERS.  All of the Securities that constitute currently outstanding
     shares of Company Common Stock (the "Current Securities") are owned by
     Prince Venture Partners III, L.P. ("Prince").  The general partner of
     Prince is Ventures.  Stockholder is the general partner of Ventures and his
     beneficial ownership of the Current Securities derives solely from his
     status as the general partner of Ventures.  Under the terms of the
     Partnership Agreement governing Prince, Prince must be wound up on
     September 15, 1998 and all of the assets of Prince are required to be
     distributed to the individual partners of Prince (the "Distributees") by
     that date (the "Distribution"), assuming that the Distributees have not
     previously taken action to amend the terms of the Partnership Agreement
     prior to that date.  Stockholder, as the general partner of Ventures,
     intends to cause Ventures, as the general partner of Prince, to effect the
     Distribution as close in time to September 15, 1998 as is consistent with
     the obligations of Ventures to ensure that the Distribution is timely made.
     The Current Securities are included in the assets that will be the subject
     of the Distribution.

4.  FURTHER ASSURANCES.  Stockholder will, from time to time, execute and
deliver, or cause to be executed and delivered, such additional or further
transfers, assignments, endorsements, consents and other instruments as Parent
may reasonably request for the purpose of effectively carrying out the
transactions contemplated by this Agreement and to vest the power to vote
Stockholder's Securities as contemplated by Section 2.

                                      -4-
<PAGE>
 
5.  ASSIGNMENT; BINDING EFFECT.  Neither this Agreement nor any of the rights,
interests or obligations hereunder shall be assigned by any of the parties
hereto (whether by operation of law or otherwise) without the prior written
consent of the other parties.  Subject to the preceding sentence, this Agreement
shall be binding upon, inure to the benefit of, and be enforceable by, the
parties hereto and their respective successors and assigns.  Notwithstanding
anything contained in this Agreement to the contrary, nothing in this Agreement,
expressed or implied, is intended to confer on any person other than the parties
hereto or their respective heirs, successors, executors, administrators and
assigns any rights, remedies, obligations or liabilities under or by reason of
this Agreement.

6.  TERMINATION.  Except as otherwise provided in Section 1(d), this Agreement,
and all rights and obligations of the parties hereunder, shall terminate upon
the earliest to occur of the Effective Time or the  termination of the Merger
Agreement in accordance with its terms.  Nothing in this Section 6 shall relieve
any party from liability for willful breach of this Agreement.

7.  STOP TRANSFER.  The Company agrees with, and covenants to, Parent that the
Company shall not register the transfer of any certificate representing any
Stockholder's Securities unless such transfer is made in accordance with the
terms of this Agreement.

8.  GENERAL PROVISIONS.

(a)  EXPENSES.  All costs and expenses incurred by Parent in connection with
     this Agreement and the transactions contemplated hereby shall be paid by
     Parent.  All costs and expenses incurred by Stockholder in connection with
     this Agreement and the transactions contemplated hereby shall be paid by
     the Company.

(b)  AMENDMENTS.  This Agreement may not be amended except by an instrument in
     writing signed by each of the parties hereto.

(c)  NOTICE.  All notices and other communications hereunder shall be in writing
     and shall be deemed given upon receipt to the parties at the following
     addresses (or at such other address for a party as shall be specified by
     like notice):

                       (i)  if to Parent, to:

                            Mylan Laboratories Inc.
                            781 Chestnut Ridge Road
                             Post Office Box 4310
                             Morgantown, WV  26505
                        Telecopy Number (304) 599-7284

                                      -5-
<PAGE>
 
                                with a copy to:

                            John R. Previs, Esquire
                  Buchanan Ingersoll Professional Corporation
                               One Oxford Centre
                          301 Grant Street, 20th Floor
                           Pittsburgh, PA  15219-1410
                         Telecopy Number (412) 562-1041

and

                      (ii) if to a Stockholder, to the address set forth under 
the name of such Stockholder on Schedule A hereto:

                                with a copy to:

                             Henry Lesser, Esquire
                        Heller Ehrman White & McAuliffe
                             525 University Avenue
                           Palo Alto, CA  94301-1300
                         Telecopy Number (650) 324-0638

(d)  INTERPRETATION.  When a reference is made in this Agreement to a Section,
     such reference shall be to a Section of this Agreement unless otherwise
     indicated.  The headings contained in this Agreement are for reference
     purposes only and shall not affect in any way the meaning or interpretation
     of this Agreement.  Wherever the words "include", "includes" or "including"
     are used in this Agreement, they shall be deemed to be followed by the
     words "without limitation".

(e)  COUNTERPARTS.  This Agreement may be executed in two or more counterparts,
     all of which shall be considered one and the same agreement and shall
     become effective when two or more counterparts have been signed by each of
     the parties and delivered to the other parties, it being understood that
     all parties need not sign the same counterpart.

(f)  ENTIRE AGREEMENT; NO THIRD-PARTY BENEFICIARIES. This Agreement (including
     the documents and instruments referred to herein) (i) constitutes the
     entire agreement and supersedes all prior agreements and understandings,
     both written and oral, among the parties with respect to the subject matter
     hereof and (ii) is not intended to confer upon any person other than the
     parties hereto any rights or remedies hereunder.

(g)  GOVERNING LAW.  This Agreement shall be governed and construed in
     accordance with the laws of the State of Delaware without regard to any
     applicable conflicts of law.

                                      -6-
<PAGE>
 
9.  STOCKHOLDER CAPACITY.  As of the date of this Agreement, Stockholder is a
director of the Company.  Stockholder makes no agreement or understanding herein
in his capacity as a director or officer of the Company.  Each Stockholder signs
solely in his capacity as the record holder and beneficial owner of, or the
trustee of a trust whose beneficiaries are the beneficial owners of,
Stockholder's Securities and nothing herein shall limit or affect any actions
taken by Stockholder in his capacity as an officer or director of the Company to
the extent specifically permitted by the Merger Agreement.

10.  ENFORCEMENT.  The parties agree that irreparable damage would occur in the
event that any of the provisions of this Agreement were not performed in
accordance with their specific terms or were otherwise breached.  It is
accordingly agreed that the parties shall be entitled to an injunction or
injunctions to prevent breaches of this Agreement and to enforce specifically
the terms and provisions of this Agreement in a court of the United States.
This being in addition to any other remedy to which they are entitled at law or
in equity.  In addition, each of the parties hereto waives any right to trial by
jury with respect to any claim or proceeding related to or arising out of this
Agreement or any of the transactions contemplated hereby.

STOCKHOLDER AGREES THAT, IN CONNECTION WITH ANY LEGAL SUIT OR PROCEEDING ARISING
WITH RESPECT TO THIS AGREEMENT, STOCKHOLDER SHALL SUBMIT TO THE JURISDICTION OF
THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE AND AGREES TO
VENUE IN SUCH COURTS.  STOCKHOLDER HEREBY APPOINTS THE SECRETARY OF THE COMPANY
AS HIS AGENT FOR SERVICE OF PROCESS FOR PURPOSES OF THE FOREGOING SENTENCE ONLY.
EACH PARTY HERETO WAIVES ANY RIGHT TO JURY TRIAL IN CONNECTION WITH ANY SUCH
SUIT OR PROCEEDING.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                      -7-
<PAGE>
 
          IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                    MYLAN LABORATORIES INC.


                                    By:    /s/ Roderick P. Jackson
                                        ---------------------------------------
                                    Name:  Roderick P. Jackson
                                    Title: Senior Vice President


                                    PRINCE VENTURE PARTNERS III L.P.

                                    PRINCE VENTURES L.P.
                                    General Partner


                                    By:  /s/ Mark J. Gabrielson
                                        ---------------------------------------
                                    Mark J. Gabrielson,
                                    General Partner


                                    /s/ Mark J. Gabrielson
                                    -------------------------------------------
                                    Mark J. Gabrielson

                                      -8-
<PAGE>
 
                                   SCHEDULE A
                                   ----------

<TABLE>
<CAPTION>

STOCKHOLDER                                                           SECURITIES HELD
- ---------------------------------------------------------  -------------------------------------
<S>                                                        <C>
Mark J. Gabrielson                                                      270,091*
c/o Penederm Incorporated
320 Lakeside Drive
Foster City, CA  94404
</TABLE>



*  Held as indicated in Section 3(e) of the foregoing Agreement.

                                      -9-

<PAGE>
 
                                                                    Exhibit 99.4


Mylan to Acquire Penederm


PITTSBURGH, Pa.--(BUSINESS WIRE)--June 24, 1998--Mylan Laboratories Inc.
(NYSE:MYL) and Penederm Inc. (NASDAQ:DERM) announced today that they have
entered into a definitive agreement whereby Mylan will acquire Penederm Inc. of
Foster City, Calif.

The boards of directors of both companies have unanimously approved the
agreement.  SBC Warburg Dillon Read advised Mylan and Lehman Brothers advised
Penederm in connection with the transaction.

Penederm develops and markets patented topically administered prescription
products.  The company currently markets three prescription products to
dermatologists in the U.S. through a 41 person direct sales force.  The products
include:  Avita(R), a topical anti-acne retinoic acid therapy formulated with
Penederm's proprietary TopiCare delivery technology; Mentax(R), their novel
antifungal compound that treats common skin fungal infections; and Acticin(R), a
topical prescription product for scabies.  Penederm has an existing partnership
with Mylan for the marketing of Mentax(R) to the U.S. primary care market.

Penederm also has a pipeline of promising compounds under active development,
two of which are in Phase III clinical development.  In order to maximize the
commercialization of its technology, Penederm has selectively licensed their
proprietary delivery system to cosmetic companies seeking to enhance the
effectiveness of their cosmetic and skin care products.

Under terms of the agreement, Penederm shareholders will receive 0.68 shares of
Mylan common stock for each share of Penederm stock.  The transaction is valued
at approximately $21.89 per share to Penederm shareholders, or approximately
$205 million based on the closing price of Mylan stock on June 23, 1998.

The transaction is subject to the approval of Penederm's stockholders and other
customary conditions.  The transaction is intended to qualify as a tax-free
reorganization.  It is expected to close before the end of the calendar year.

The companies believe that significant opportunities exist in their joint
marketing and sales efforts.  This combined proprietary product line will be
marketed through Bertek Pharmaceuticals Inc., a wholly owned subsidiary of Mylan
Laboratories Inc.  On a combined basis, Mylan's sales efforts would include a
170 person sales force calling on physicians in both the primary care and
dermatology markets with a product line that includes seven proprietary
prescription products.

In addition, it is anticipated that Penederm's current R&D efforts will not only
continue, but will be expanded to include some of Mylan's research projects that
have the potential to be improved by Penederm's drug delivery technology.
<PAGE>
 
Commenting on the acquisition, Milan Puskar, Chairman and CEO and President of
Mylan noted that "Penederm is an excellent strategic fit with Mylan.  We expect
their products and sales force to meaningfully add to our proprietary product
line and marketing efforts.  In addition, Penederm's current products under
development offer significant opportunities for our combined shareholders.  We
see numerous opportunities to apply Penederm's patented drug delivery technology
to products we have under development."

Lloyd Malchow, President and CEO of Penederm added that "The Penederm Board is
very pleased to be able to offer our stockholders this opportunity to exchange
their shares for significant equity investment in Mylan.  We believe this
transaction will enhance significantly Penederm's ability to pursue its product
development and marketing plans."

Addressing the near-term financial effects of the merger, Don Schilling, Mylan's
VP of Finance commented that "Mylan expects that the acquisition will be
basically neutral for the remainder of Mylan's current fiscal year which ends
March 31, 1999, excluding the effects of the one-time write-off of purchased
R&D."  Elaborating further, Schilling stated that "Mylan expects the transaction
to be accretive to earnings in our next fiscal year which begins April 1, 1999
and ends March 31, 2000.  The acquisition will be accounted for under the
purchase method of accounting."

CONTACT:

Mylan Laboratories Inc.

Patricia Sunseri, 412/232-0100

or

Penederm Incorporated


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