HYBRIDON INC
10-Q, 1999-11-15
BIOLOGICAL PRODUCTS, (NO DIAGNOSTIC SUBSTANCES)
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    As filed with the Securities and Exchange Commission on November 15, 1999

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 10-Q


[X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES  EXCHANGE
ACT OF 1934

For the quarterly period ended September 30, 1999, or

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
ACT OF 1934

For transition period from _________________.

Commission File Number 0-27352

                                 HYBRIDON, INC.
             (Exact name of registrant as specified in its charter)

            Delaware                                 04-3072298
- -------------------------------         ----------------------------------------
(State or other jurisdiction of         (I.R.S. Employer Identification  Number)

incorporation or organization)


                                155 Fortune Blvd.
                          Milford, Massachusetts 07157
                    (Address of principal executive offices)

                                 (508) 482-7500
              (Registrant's telephone number, including area code)


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                  Yes |X|  No |_|


Indicate the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practicable date.

Common Stock, par value $.001 per share                   16,262,722
- ---------------------------------------      -----------------------------------
Class                                        Outstanding as of November 12, 1999

<PAGE>

                                 HYBRIDON, INC.
                                    FORM 10-Q
                                      INDEX



PART I - FINANCIAL STATEMENTS
Item 1-       Financial Statements

          Consolidated  Condensed  Balance  Sheets as of September  30, 1999 and
          December 31, 1998.

          Consolidated  Condensed  Statements of Operations for the Three Months
          and Nine Months ended September 30, 1999 and 1998.

          Consolidated  Condensed  Statements  of Cash Flows for the Nine Months
          ended September 30, 1999 and 1998.

          Notes to Consolidated Condensed Financial Statements.


Item 2 -  Management's Discussion and Analysis of Financial Condition and
          Results of Operations.

Item 3 -  Quantitative and Qualitative Disclosure About Market Risk.


PART II - OTHER INFORMATION

Items 1-3  None

Item 4     None

Item 5     Other Information

Item 6     Exhibits and Reports on Form 8-K

Signatures


                                       2
<PAGE>

                         HYBRIDON, INC. AND SUBSIDIARIES

                      CONSOLIDATED CONDENSED BALANCE SHEETS

                                   (UNAUDITED)

                                     ASSETS
                                                         September      December
                                                         30, 1999       31, 1998
CURRENT ASSETS:
   Cash and cash equivalents                           $   500,179   $ 5,607,882
   Accounts receivable                                     838,852     1,175,441
   Prepaid expenses and other current assets               102,185       110,827
                                                       -----------   -----------

         Total current assets                            1,441,216     6,894,150
                                                       -----------   -----------
PROPERTY AND EQUIPMENT, AT COST:
   Leasehold improvements                               11,127,035    11,127,035
   Laboratory and other equipment                        9,988,579    11,432,435
                                                       -----------   -----------
                                                        21,115,614    22,559,470

   Less--Accumulated depreciation and amortization      14,162,190    13,788,979
                                                       -----------   -----------
                                                         6,953,424     8,770,491
                                                       -----------   -----------
OTHER ASSETS:
   Deferred financing costs and other assets               531,423       612,374
   Notes receivable from officers                          267,200       258,650
                                                       -----------   -----------

                                                           798,623       871,024
                                                       -----------   -----------

                                                       $ 9,193,263   $16,535,665
                                                       ===========   ===========

                 LIABILITIES AND STOCKHOLDERS' (DEFICIT) EQUITY

CURRENT LIABILITIES:
   Current portion of long-term debt             $   6,078,179    $   6,070,951
   Related party promissory notes payable            1,000,000               --
   Accounts payable                                  2,512,738        2,368,163
   Accrued expenses                                  2,389,804        4,068,679
                                                 -------------    -------------
         Total current liabilities                  11,980,721       12,507,793

LONG-TERM DEBT, NET OF CURRENT PORTION                 413,523          473,094
                                                 -------------    -------------
9% CONVERTIBLE SUBORDINATED NOTES PAYABLE            1,306,000        1,306,000
                                                 -------------    -------------
STOCKHOLDERS' (DEFICIT)EQUITY:
   Preferred stock, $.01 par value-
     Authorized--5,000,000 shares
     Series A convertible preferred stock-
         Designated - 1,500,000 shares
         Issued and outstanding--641,023
         and 641,259 shares at September
         30, 1999 and December 31, 1998,
            respectively                                 6,410            6,413
            (Liquidation preference of $00
            at September 30, 1999)
   Common stock, $.001 par value-
     Authorized--100,000,000 shares
     Issued and outstanding - 16,260,731 and
     15,304,825 shares,
     respectively                                       16,261           15,305
   Additional paid-in capital                      246,227,811      241,632,024
   Accumulated deficit                            (249,974,144)    (238,447,837)
   Deferred compensation                              (783,319)        (957,127)
                                                 -------------    -------------

         Total stockholders' (deficit) equity       (4,506,981)       2,248,778
                                                 -------------    -------------
                                                 $   9,193,263    $  16,535,665
                                                 =============    =============

              The accompanying notes are an integral part of these
                  consolidated condensed financial statements.


                                       3
<PAGE>
                         Hybridon, Inc. and Subsidiaries

                 CONSOLIDATED CONDENSED STATEMENTS OF OPERATIONS

                                   (UNAUDITED)
<TABLE>
<CAPTION>
                                              Three Months Ended             Nine Months Ended
                                                 September 30,                  September 30,
                                            1999              1998         1999            1998
REVENUES:
<S>                                    <C>              <C>             <C>             <C>
  Product and service revenue         $  1,577,125    $    846,746    $  4,643,842    $  2,353,435
  Research and development                 150,000         150,000         450,000         949,915
  Interest income                           12,540          44,010          81,724         106,457
  Royalty and other income                  51,970              --         106,950              --
                                      ------------    ------------    ------------    ------------

                                         1,791,635       1,040,756       5,282,516       3,409,807
                                      ------------    ------------    ------------    ------------
OPERATING EXPENSES:
   Research and development              3,414,782       5,201,246      10,106,459      17,180,927
    General and administrative             884,109       1,503,845       2,946,564       5,817,864
   Interest                                224,555         296,344         561,949       2,880,307
                                      ------------    ------------    ------------    ------------

                                         4,523,446       7,001,435      13,614,972      25,879,098
                                      ------------    ------------    ------------    ------------

         Loss from operations           (2,731,811)     (5,960,679)     (8,332,456)    (22,469,291)

EXTRAORDINARY ITEM:
   Gain on conversion of 9%
   convertible subordinated notes
   payable                                      --              --              --       8,876,685
                                      ------------    ------------    ------------    ------------

NET LOSS                                (2,731,811)     (5,960,679)     (8,332,456)    (13,592,606)
                                      ------------    ------------    ------------    ------------

ACCRETION OF PREFERRED STOCK
DIVIDENDS                                1,075,899       1,026,500       3,193,851       1,647,000
                                      ------------    ------------    ------------    ------------

NET LOSS APPLICABLE TO COMMON
STOCKHOLDERS                          $ (3,807,710)   $ (6,987,179)   $(11,526,307)   $(15,239,606)
                                      ============    ============    ============    ============

BASIC AND DILUTED LOSS PER COMMON
SHARE  FROM (Note 3):

   LOSS BEFORE EXTRAORDINARY
   ITEM                               $      (0.17)   $      (0.39)   $      (0.54)   $      (2.11)

   EXTRAORDINARY ITEM                           --              --              --            0.83
                                      ------------    ------------    ------------    ------------

   NET LOSS PER SHARE                        (0.17)          (0.39)          (0.54)          (1.28)

   ACCRETION OF PREFERRED STOCK
   DIVIDENDS                                 (0.07)          (0.07)          (0.20)          (0.15)
                                      ------------    ------------    ------------    ------------
   NET LOSS PER SHARE APPLICABLE TO
   COMMON STOCKHOLDERS                $      (0.24)   $      (0.46)   $      (0.74)   $      (1.43)
                                      ============    ============    ============    ============

SHARES USED IN COMPUTING BASIC AND
DILUTED NET LOSS PER COMMON SHARE
(Note 3)                                15,984,146      15,254,825      15,653,562      10,648,116
                                      ============    ============    ============    ============
</TABLE>

              The accompanying notes are an integral part of these
                  consolidated condensed financial statements

                                       4
<PAGE>

                         HYBRIDON, INC. AND SUBSIDIARIES

                 CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS

                                   (UNAUDITED)

<TABLE>
<CAPTION>

                                                                            Nine Months Ended
                                                                              September 30,
                                                                          1999             1998
CASH FLOWS FROM OPERATING ACTIVITIES:
<S>                                                                  <C>             <C>
   Net loss                                                         $ (8,332,456)   $(13,592,606)
   Adjustments to reconcile net loss to net cash used in
   operating activities-
     Extraordinary gain on conversion of 9% convertible
       subordinated notes payable                                             --      (8,876,685)
     Depreciation and amortization                                     1,825,370       2,419,269
     Loss on disposal of fixed assets                                         --         424,675
     Amortization of deferred compensation                               576,697         163,044
     Amortization of deferred financing costs                             80,951         240,611
     Changes in operating assets and liabilities-
       Accounts receivable                                               336,589        (295,966)
       Prepaid and other current assets                                    8,642         557,703
       Notes receivable from officers                                     (8,550)         (8,550)
       Accounts payable and accrued expenses                            (534,300)        328,673
                                                                    ------------    ------------

              Net cash used in operating activities                   (6,047,057)    (18,639,832)
                                                                    ------------    ------------

CASH FLOWS FROM INVESTING ACTIVITIES:
   Purchases of property and equipment, net                               (8,303)       (340,507)
   Proceeds from sale of fixed assets                                         --         460,000
                                                                    ------------    ------------

              Net cash (used in) provided by investing activities         (8,303)        119,493
                                                                    ------------    ------------

CASH FLOWS FROM FINANCING ACTIVITIES:
   Proceeds from issuance of convertible preferred stock                      --       7,999,960
   Net proceeds from issuance of common stock                                 --       6,876,676
   Proceeds from issuance of convertible promissory notes payable             --       4,233,833
   Proceeds from related party promissory notes payable                1,000,000              --
   Payments on long-term debt and capital leases                         (52,343)     (4,236,693)
   Decrease in restricted cash and other assets                               --       2,327,186
                                                                    ------------    ------------

              Net cash provided by financing activities                  947,657      17,200,962
                                                                    ------------    ------------

NET DECREASE IN CASH AND CASH EQUIVALENTS                             (5,107,703)     (1,319,377)

CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD                         5,607,882       2,202,202
                                                                    ------------    ------------
</TABLE>


                                       5
<PAGE>

<TABLE>
<CAPTION>
<S>                                                                 <C>             <C>
CASH AND CASH EQUIVALENTS, END OF PERIOD                            $    500,179    $    882,825
                                                                    ============    ============

SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
   Cash paid for interest                                           $    532,564    $  1,494,323
                                                                    ============    ============
SUPPLEMENTAL DISCLOSURE OF NONCASH ACTIVITIES:
   Accretion of Series A convertible preferred stock dividend       $  3,193,851    $  1,026,500
                                                                    ============    ============
   Issuance of common stock in lieu of services                     $  1,000,000    $         --
                                                                    ============    ============
   Issuance of Series A convertible preferred stock and
     attached warrants in exchange for conversion of 9%
     convertible subordinated notes payable and accrued interest    $         --    $ 51,055,850
                                                                    ============    ============
   Issuance of common stock and attached warrants in exchange for
     conversion of convertible promissory notes payable             $         --    $  4,800,000
                                                                    ============    ============
  Issuance of common stock and attached warrants in exchange for
     conversion of accounts payable and other obligations           $         --    $  5,934,558
                                                                    ============    ============
   Conversion of Series A convertible preferred stock into shares
     of common stock                                                $        486    $         --
                                                                    ============    ============
</TABLE>

              The accompanying notes are an integral part of these
                  consolidated condensedfinancial statements.


                                       6
<PAGE>

                         Hybridon, Inc. and Subsidiaries

              NOTES TO CONSOLIDATED CONDENSED FINANCIAL STATEMENTS

                                   (UNAUDITED)

(1)      ORGANIZATION

         Hybridon, Inc. (the Company) was incorporated in the State of Delaware
         on May 25, 1989. The Company is engaged in the discovery and
         development of novel genetic medicines based primarily on antisense
         technology.

         Since inception, the Company has been engaged primarily in research and
         development efforts, development of its manufacturing capabilities and
         organizational efforts, including recruiting of scientific and
         management personnel and raising capital. To date, the Company has not
         received revenue from the sale of biopharmaceutical products developed
         by it based on antisense technology. In order to commercialize its own
         products, the Company will need to address a number of technological
         challenges and comply with comprehensive regulatory requirements.
         Accordingly, it is not possible to predict the amount of funds that
         will be required or the length of time that will pass before the
         Company receives revenues from sales of any of these products. All
         revenues received by the Company to date have been derived from
         collaboration agreements, interest on investment funds and revenues
         from the custom contract manufacturing of synthetic DNA and reagent
         products by the Company's Hybridon Specialty Products Division. As a
         result, although the Company has begun to generate revenues from its
         contract manufacturing business, the Company is dependent on the
         proceeds from possible future sales of equity securities, debt
         financings and research and development collaborations in order to fund
         future operations.

         The Company is currently seeking debt or equity financing in an amount
         sufficient to support its (operations through at least the end of 1999,
         and in connection therewith, is in negotiations to obtain such
         financing. Subsequent to September 30, 1999, the Company obtained
         approximately $500,000 under a loan agreement (the Loan) from new and
         existing investors (the New Investors). No later than December 31,
         1999, the Loan will be converted, at the option of the New Investors,
         into either (i) preferred stock or (ii) secured debt, as defined. In
         addition, the Company has also received approximately $500,000 (and an
         additional $400,000 in escrow) under the terms of its current debt
         offering of 8% Notes convertible to common stock at $.60 per share.
         While the terms of this financing have been agreed to, the parties have
         not yet finalized the documentation. It is therefore possible that the
         Company may not consummate this financing and gain use of these funds.
         The Company does not, however, anticipate any such difficulties. If the
         Company is unable to obtain additional financing by the end of 1999, it
         will be forced to obtain funds through arrangements with collaborative
         partners or others that may require it to relinquish rights to certain
         of its technologies, product candidates or products which it would
         otherwise pursue on its own, or terminate operations or seek relief
         under applicable bankruptcy laws.

         On December 3, 1997, the Company was delisted from the Nasdaq Stock
         Market, Inc. (NASDAQ) because the Company was not in compliance with
         the continued listing requirements of the NASDAQ National Market. The
         Company is currently trading on the NASD OTC as a result of the
         delisting.


(2)      UNAUDITED INTERIM FINANCIAL STATEMENTS

         The unaudited consolidated condensed financial statements included
         herein have been prepared by the Company, without audit, pursuant to
         the rules and regulations of the Securities and Exchange Commission and
         include, in the opinion of management, all adjustments, consisting of
         normal, recurring adjustments, necessary for a fair presentation of
         interim period results. Certain information and footnote disclosures
         normally included in financial statements prepared in accordance with
         generally accepted accounting principles have been condensed or omitted
         pursuant to such rules and regulations. The Company believes, however,
         that its disclosures are adequate to make the information presented not
         misleading. The results for the interim periods


                                       7
<PAGE>

                         Hybridon, Inc. and Subsidiaries

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

                                   (Continued)

         presented are not necessarily indicative of results to be expected for
         the full fiscal year. It is suggested that these financial statements
         be read in conjunction with the audited consolidated financial
         statements and notes thereto included in the Company's Annual Report on
         Form 10-K for the year ended December 31, 1998, as filed with the
         Securities and Exchange Commission.

(3)      SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

         Net Loss per Common Share

         The Company follows the provisions of Statement of Financial Accounting
         Standards (SFAS) No. 128, Earnings per Share. Under SFAS No. 128, basic
         net loss per share applicable to common shareholders is computed using
         the weighted average number of shares of common stock outstanding
         during the period. Diluted net loss per common share is the same as
         basic net loss per common as the effects of the Company's potential
         common stock equivalents are antidilutive.

         Comprehensive Loss

         The Company follows the provisions of SFAS No. 130, Reporting
         Comprehensive Income. Comprehensive loss is defined as the change in
         equity of a business enterprise during a period from transactions and
         other events and circumstances from nonowner sources. The Company's
         comprehensive loss is the same as the reported net loss for all periods
         presented.

         Segment Reporting

         The Company follows the provisions of SFAS No. 131, Disclosures About
         Segments of an Enterprise and Related Information. SFAS No. 131
         establishes standards for reporting information regarding operating
         segments in annual financial statements and requires selected
         information for those segments to be reported in interim financial
         reports issued to stockholders. SFAS No. 131 also establishes standards
         for related disclosures about products and services and geographic
         areas. To date, the Company has viewed its operations and manages its
         business as principally one operating segment. As a result, the
         financial information disclosed herein, represents all of the material
         financial information related to the Company's principal operating
         segment. All of the Company's revenues are generated in the United
         States and substantially all assets are located in the United States.

(4)      CASH EQUIVALENTS

         The Company considers all highly liquid investments with maturities of
         three months or less when purchased to be cash equivalents. Cash and
         cash equivalents at September 30, 1999 and December 31, 1998 consisted
         of the following (at amortized cost, which approximates fair market
         value):
                                                     September         December
                                                     30, 1999          31, 1998
             Cash and cash equivalents-
               Cash and money market funds          $  407,966        $3,865,365
               Corporate bond                           92,213         1,742,517
                                                    ----------        ----------
                                                    $  500,179        $5,607,882
                                                    ==========        ==========


                                       8
<PAGE>

                         Hybridon, Inc. and Subsidiaries

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

                                   (Continued)


(5)      9.0% CONVERTIBLE SUBORDINATED NOTES

         On April 2, 1997, the Company issued $50,000,000 of 9.0% convertible
         subordinated notes (the 9% Notes). On May 5, 1998 noteholders holding
         $48.7 million of principal value of the 9% Notes tendered such notes in
         exchange for Series A convertible preferred stock, approximately
         $2,355,000 of accrued interest thereon was converted into shares of
         Series A convertible preferred stock and warrants to purchase common
         stock. As of September 30, 1999, there is $1.3 million of 9% Notes
         outstanding. Under the terms of the 9% Notes, the Company must make
         semi-annual interest payments on the outstanding principal balance
         through the maturity date of April 1, 2004. If the 9% Notes are
         converted prior to April 1, 2000, the Noteholders are entitled to
         receive accrued interest from the date of the most recent interest
         payment through the conversion date. The 9% Notes are convertible at
         any time prior to the maturity date at a conversion price equal to
         $35.0625 per share, subject to adjustment under certain circumstances,
         as defined.

         Beginning April 1, 2000, the Company may redeem the 9% Notes at its
         option for a 4.5% premium over the original issuance price, provided
         that from April 1, 2000 to March 31, 2001, the 9% Notes may not be
         redeemed unless the closing price of the common stock equals or exceeds
         150% of the conversion price for a period of at least 20 out of 30
         consecutive trading days and the 9% Notes redeemed within 60 days after
         such trading period. The premium decreases by 1.5% each year through
         March 31, 2003. Upon a change of control of the Company, as defined,
         the Company will be required to offer to repurchase the 9% Notes at
         150% of the original issuance price.

(6)      NOTE PAYABLE TO LENDERS

         During November 1998, the Company entered into a $6,000,000 note
         payable with Forum Capital Markets, LLC (Forum) and certain investors
         associated with Pecks Management Partners Ltd. (collectively, the
         Lenders). The terms of the note payable are as follows: (i) the
         maturity is November 30, 2003; (ii) the interest rate is 8%; (iii)
         interest is payable monthly in arrears, with the principal due in full
         at maturity of the loan; (iv) the note payable is convertible, at the
         Lender's option, in whole or in part, into shares of common stock at a
         rate equal to $2.40 per share; (v) the note includes a minimum
         liquidity covenant of $2,000,000; and (vi) the note payable may not be
         prepaid, in whole or in part, at any time prior to December 1, 2000.
         The Company has received waivers of noncompliance with the minimum
         tangible net worth covenant and for the minimum liquidity covenant
         through November 30, 1999. The Company has classified the outstanding
         balance of $6,000,000 at September 30, 1999 and December 31, 1998 as a
         current liability in the accompanying consolidated balance sheet at it
         does not expect to remain in compliance with the financial covenants.
         In connection with refinancing the note payable to a bank, Forum
         received $400,000, which was reinvested by Forum to purchase 160,000
         shares of common stock with 40,000 attached warrants at an exercise
         price of $3.00 per share. The Company has recorded the $400,000 as a
         deferred financing cost, which will be amortized to interest expense
         over the term of the note. In addition, Forum received warrants to
         purchase 133,333 shares of common stock of the Company at $3.00 per
         share. The Company computed the value of the warrants to be $85,433, by
         using the Black-Scholes option pricing model. The Company has recorded
         this $85,433 as a deferred financing cost, which will be amortized to
         interest expense over the term of the note.


                                       9
<PAGE>

(7)      RELATED PARTY PROMISSORY NOTES PAYABLE

         During September 1999, the Company entered into two $500,000 promissory
         notes payable with the Company's Chief Executive Officer and President
         (the Lender). The terms of the promissory notes payable are as follows:
         (i) the maturity is March 1, 2000, subject to certain conditions, as
         defined; (ii) interest is payable at the option of the Lender at either
         (a) 12% payable in cash, or (b) 15% payable in common stock of the
         Company at $.50 per share; (iii) interest is payable monthly in
         arrears, beginning October 1, 1999; and (iv) the term note may be
         prepaid in whole or in part, at anytime without penalty. The promissory
         notes payable are secured by substantially all tangible and intangible
         assets of the Company.

(8)      STOCK OPTION REPRICING

         In September 1999, the Company's Board of Directors authorized a
         repricing of all outstanding stock options. Under the terms of the
         repricing, all current option holders (5,251,827 shares) had their
         options repriced to an exercise price of $.50 per share. Under
         Accounting Principles Board Opinion No. 25, the Company is required to
         use variable plan accounting for these options until their expiration
         or exercise.


                                       10
<PAGE>

ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
         RESULTS OF OPERATIONS

GENERAL

Hybridon is engaged in the discovery and development of genetic medicines based
on antisense technology. Hybridon commenced operations in February 1990 and
since that time has been engaged primarily in research and development efforts,
developing its manufacturing capabilities and raising capital. In order to
commercialize its therapeutic products, Hybridon will need to raise substantial
additional funds, as well as to address a number of technological challenges and
comply with comprehensive regulatory requirements. All revenues received by
Hybridon to date have been derived from collaborative agreements, interest on
invested funds and revenues from the custom contract manufacturing of synthetic
DNA and reagent products by Hybridon Specialty Products ("HSP").

Hybridon has incurred cumulative losses from inception through September 30,
1999 of approximately $250.0 million. Hybridon has significantly reduced its
operating expenses pursuant to a restructuring commenced in the second half of
1997 and completed in 1998. Hybridon expects that, assuming adequate financing
can be obtained, its research and development expenses will be significant in
1999 and future years as it pursues its core drug development programs and
expects to continue to incur operating losses and have significant capital
requirements that it will not be able to satisfy with internally generated
funds. As of November 12, 1999, the Company had 45 full-time employees.


RESULTS OF OPERATIONS

THREE AND NINE MONTHS ENDED SEPTEMBER 30, 1999 AND 1998

Hybridon had total revenues of $1.8 million and $1.0 million for the three
months ended September 30, 1999 and 1998, respectively, and had total revenues
of $5.3 million and $3.4 million for the nine months ended September 30, 1999
and 1998, respectively. Revenues from products and services were $1.6 million
and $0.8 million for the three months ended September 30, 1999 and 1998,
respectively, and $4.6 million and $2.4 million for the nine months ended
September 30, 1999 and 1998, respectively. The increase was primarily the result
of increased sales to HSP customers and receipt of service revenues from
MethylGene, Inc., an entity in which the Company has an approximately 30% equity
interest and OriGenix Technologies, Inc., an entity in which the Company has an
approximately 49% equity interest.

Revenues from research and development collaborations were $0.2 million for both
the three months ended September 30, 1999 and 1998, and $0.5 million and $0.9
million for the nine months ended September 30, 1999 and 1998, respectively.
This decrease was primarily due to a reduction in revenues recorded under a
License Agreement with MethylGene, Inc.

Hybridon's research and development expenses were $3.4 million and $5.2 million
for the three months ended September 30, 1999 and 1998, respectively, and $10.1
million and $17.2 million for the nine months ended September 30, 1999 and 1998,
respectively. The decrease reflects Hybridon's reduction of its operating
expenses in 1997 and 1998 pursuant to the restructuring commenced in 1997 and
completed in 1998 and the lower levels of cash available for expenditures in
1999. The restructuring included the discontinuation of operations at Hybridon's
facilities in Europe, and also resulted in significant reductions in employees
and employee-related expenses, clinical and outside testing, consulting,
materials and lab expenses.

In addition, the facilities expense included in research and development
expenses decreased significantly in 1999 as a result of the relocation of the
Company's corporate offices and lab space in July 1998 from Cambridge to
Milford, Massachusetts and the sublease of its unused facilities.

Hybridon's general and administrative expenses were $0.9 million and $1.5
million for the three months ended September 30, 1999 and 1998, respectively,
and $2.9 million and $5.8 million for the nine months ended September 30, 1999
and 1998, respectively. The decrease reflects Hybridon's reduction of its
operating expenses in 1997 and


                                       11
<PAGE>

1998 pursuant to the restructuring commenced in 1997 and completed in 1998 and
which resulted in significant reduction in employees and employee-related
expenses and consulting expenses. General and administrative expenses related to
business development, public relations and legal and accounting expenses also
decreased in 1999.

In addition, the facilities expense included in general and administrative
expenses also decreased significantly in 1999 as a result of the relocation of
the Company's corporate offices to Milford, Massachusetts in 1998.

Hybridon's patent expenses remained at approximately the same level in 1999 as
1998.

Hybridon's interest expense was $0.2 million and $0.3 million for the three
months ended September 30, 1999 and 1998, respectively, and $0.6 million and
$2.9 million for the nine months ended September 30, 1999 and 1998,
respectively. The decrease is attributable to the exchange of approximately
$48.7 million of the 9% convertible subordinated notes (the "9% Notes") issued
in the second quarter of 1997 for Series A Preferred Stock on May 5, 1998. In
addition, the outstanding balance of borrowings to finance the purchase of
property and equipment was reduced in May 1998, resulting in a subsequent
reduction in interest expense.

As a result of the above factors, Hybridon incurred net losses from operations
of $2.7 million and $6.0 million for the three months ended September 30, 1999
and 1998, respectively, and $8.3 million and $22.5 million for the nine months
ended September 30, 1999 and 1998, respectively.

Hybridon had extraordinary income of $8.9 million for the nine months ended
September 30, 1998 resulting from the conversion of $48.7 million principal
amount of 9% Notes to Series A Convertible Preferred Stock in the second quarter
of 1998. As a result of this transaction, the Company reduced its net loss to
$13.6 million for the nine months ended September 30, 1998.

Hybridon had accretion of preferred stock dividends of $1.1 million and $1.0
million for the three months ended September 30, 1999 and 1998, respectively,
and $3.2 million and $1.6 million for the nine months ended September 30, 1999
and 1998, respectively, to reflect the accrued portion of dividends payable to
the holders of Series A Preferred Convertible Stock, resulting in a net loss to
common stockholders of $3.8 million and $7.0 million for the three months ended
September 30, 1999 and 1998, respectively, and a net loss to common stockholders
of $11.5 million and $15.2 million for the nine months ended September 30, 1999
and 1998, respectively.

LIQUIDITY AND CAPITAL RESOURCES

During the nine months ended September 30, 1999, Hybridon used approximately
$6.0 million to fund operating activities. The primary use of cash for operating
activities was to fund a portion of Hybridon's operating loss of $8.3 million.

Hybridon had cash and cash equivalents of $0.5 million at September 30, 1999.
However, since that date, Hybridon has expended a portion of such cash resources
and continues to have substantial obligations to lenders, real estate landlords,
trade creditors and others. On November 12, 1999, Hybridon's obligations
included a $1.0 million loan described below with E. Andrews Grinstead III,
Hybridon's Chairman and President, $1.3 million principal amount of 9% Notes, a
$6.0 million loan with Forum Capital Markets, LLC and others (collectively, the
"Lenders"), a $0.5 million loan as described below, approximately $0.5 million
in 8% Convertible Notes as described below, and approximately $2.3 million of
accounts payable. Because of Hybridon's financial condition, many trade
creditors are only willing to provide Hybridon with products and services on a
cash on delivery basis. The note to the Lenders contains certain financial
covenants that require Hybridon to maintain minimum tangible net worth and
minimum liquidity. Hybridon is not in compliance with those covenants. However,
Forum Capital Markets has granted Hybridon a waiver of compliance with the
minimum tangible net worth requirement and the minimum liquidity requirement at
September 30, 1999 and has agreed not to require that Hybridon comply with those
requirements for any periods commencing October 1, 1999 through November 30,
1999. A representative of the other Lenders has indicated informally to Hybridon
that the other Lenders intend to do likewise, but they have not yet entered into
a written agreement to that effect.


                                       12
<PAGE>

On September 1, 1999 and September 27, 1999, Hybridon entered into two six
month, $500,000 promissory notes payable and a loan agreement with E. Andrews
Grinstead III, Hybridon's Chairman and President. The loan is payable with
interest, at the option of the lender, at the rate of either (a) 12% per annum,
payable in cash or (b) 15% per annum, payable in Hybridon's common stock at the
rate of $0.50 per share. Interest is due and payable monthly in arrears on the
first business day of each month commencing on October 1, 1999 until March 1,
2000. The loan agreement provides that it is the intent of the parties that upon
the closing of any third party debt financing on or before March 1, 2000, this
loan will be converted into a portion of the credit facility made pursuant to
such debt financing. If for any reason the third party debt financing does not
close on or before March 1, 2000, the lender will have the option (a) to convert
the entire loan to a five-year term loan bearing interest at 8% per annum, with
the right to receive warrants to purchase in the aggregate 2,100,000 shares of
Hybridon common stock at per-share exercise prices of $1.50 (for three-year
warrants) and $1.25 (for four-year warrants), subject to downward adjustment, at
the one-year anniversary of the warrant issuance date, to the per-share market
price of Hybridon's common stock, in the case of the warrants having a $1.50
exercise price, and to 83.3% of the per-share market price of Hybridon's common
stock, in the case of the warrants with a $1.25 exercise price, if the market
price does not exceed $1.50, (b) to convert the entire loan to a demand loan
bearing interest at the lender's option at either (i) 12% per annum, payable in
cash or (ii) 15% per annum, payable in Hybridon's common stock at the rate of
$0.50 per share, or (c) to declare the entire principal and interest immediately
due and payable. The loan may be prepaid without premium or penalty at any time.
The loan is secured by substantially all the assets of Hybridon.

During October and November 1999, Hybridon raised approximately %500,000 under a
loan agreement with various parties. The loan will be converted, at the lenders'
option, into either (a) preferred equity, or (b) secured debt, no later than
December 31, 1999, as described below. Hybridon will pay the lenders interest
monthly in arrears on the unpaid principal amount of the loan at the rate of 8%
per annum, payable in common stock at the rate of $0.50 per share, on the first
business day of each month that the loan is outstanding, commencing November 1,
1999. The loan may be prepaid without premium or penalty at any time. Any
preferred stock into which such loan is converted will (i) rank senior to
existing preferred stock, but junior to all debt, (ii) will be paid a dividend
of 8% per annum, payable semi-annually in arrears, which will be payable in
Hybridon common stock, priced at the market price on the record date, (iii) will
be convertible to Hybridon common stock at the rate of $0.50 per share at any
time and (iv) will be callable by Hybridon at any time after three years. Any
secured debt into which such loan will be converted will (a) have a five-year
term, (b) will bear 8% interest, payable semi-annually in arrears, payable in
cash or Hybridon common stock, at Hybridon's option, (c) will be convertible
into common stock at $0.60 per share, (d) will be prepayable by Hybridon, in
whole or in part, at any time in cash; provided however, that if the loan is
prepaid at Hybridon's election during the first three years of the term,
Hybridon will issue a number of warrants with an exercise price of $0.60 per
share to purchase common stock equal to the number of shares into which the
amount prepaid was convertible, (e) will be secured by all assets of Hybridon
and (f) will rank pari passu with the current $6.0 million loan held by the
Lenders.

During October 1999, Hybridon commenced an offering that will extend through
December 1999. If such offering is consummated, the September notes and October
loans described above are expected to convert and become part of the offering.
The terms of the offering are as follows: (a) three-year term; (b) interest rate
of 8%, payable semi-annually in arrears; (c) interest is payable in cash or in
additional notes, at Hybridon's option; (d) convertible into common stock at
$0.60 per share; (e) prepayable by Hybridon, in whole or in part, at any time in
cash; (f) if prepaid at Hybridon's election during the first three years of the
term, Hybridon will issue a number of warrants to purchase common stock equal to
the number of shares into which the amount prepaid was convertible, with a $0.60
strike price; and (g) secured by substantially all assets. The securities
offered have not been and will not be registered under the Securities Act and
may not be offered or sold in the U.S. absent registration or an applicable
exemption from registration requirements. As of November 15, 1999, Hybridon had
received approximately $500,000 (and an additional $400,000 in escrow) under the
terms of this offering. While the terms of this financing have been agreed to,
the parties have not yet finalized the documentation. It is therefore possible
that Hybridon may not consummate this financing and gain use of these funds.
Hybridon does not, however, anticipate any such difficulties.

Hybridon's ability to continue operations in 1999 depends on its success in
obtaining new funds in the immediate future. Hybridon is currently seeking debt
or equity financing in an amount sufficient to support its operations into 2000,
and in connection therewith, is in negotiations with several parties to obtain
such financing. However, there can be no assurance that Hybridon will obtain any
funds or as to the timing thereof. Hybridon's existing cash resources are
expected to be sufficient to fund Hybridon's operations through the end of
1999. If Hybridon is unable to obtain substantial additional new funding by the
end of 1999, Hybridon will be required to obtain funds through arrangements with
collaborative partners or others that may require it to relinquish rights to


                                       13
<PAGE>

certain of its technologies, product candidates or products which it would
otherwise pursue on its own, or terminate operations or seek relief under
applicable bankruptcy laws.

HISTORY OF OPERATING LOSSES; UNCERTAINTY OF FUTURE PROFITABILITY

Since inception, Hybridon has incurred significant losses, which it has funded
through the issuance of equity securities, debt issuances, sales by HSP, and
through research and development collaborations and licensing arrangements.

FUTURE CAPITAL NEEDS; UNCERTAINTY OF ADDITIONAL FUNDING

Even though Hybridon has obtained sufficient cash to fund its operations for the
balance of 1999, it will be required to raise substantial additional funds
through external sources, including through collaborative relationships and
public or private financing, to support its operations throughout 2000 and
beyond. Except for research and development funding from Searle under its
collaborative agreement with Searle (which is subject to early termination in
certain circumstances), Hybridon has no committed external sources of capital,
and, as discussed above, expects no product revenues for several years from
sales of the therapeutic products that it is developing (as opposed to sales of
DNA products and reagents manufactured and sold by HSP).

No assurance can be given that additional funds will be available to fund
operations for the balance of 1999 or in future years, or, if available, that
such funds will be available on acceptable terms. If additional funds are raised
by issuing equity securities, further dilution to then existing stockholders
will result. Additionally, the terms of any such additional financing may
adversely affect the holdings or rights of then existing stockholders.

Hybridon's future capital requirements will depend on many factors, including
continued scientific progress in its research, drug discovery and development
programs, the magnitude of these programs, progress with preclinical and
clinical trials, sales of DNA products and reagents to third parties by HSP and
the margins on such sales, the time and costs involved in obtaining regulatory
approvals, the costs involved in filing, prosecuting and enforcing patent
claims, competing technological and market developments, Hybridon's ability to
establish and maintain collaborative academic and commercial research,
development and marketing relationships, its ability to obtain third-party
financing for leasehold improvements and other capital expenditures and the
costs of manufacturing scale-up and commercialization activities and
arrangements.

YEAR 2000; CONTINGENCY PLANS

As has been widely publicized, many computer systems and microprocessors are not
programmed to accommodate dates beyond the year 1999. Hybridon's exposure to
this year 2000 ("Y2K") problem comes not only from its own internal computer
systems and microprocessors, but also from the systems and microprocessors of
its key suppliers, including utility companies and payroll services.

Hybridon believes that all of its internal systems will be Y2K compliant by the
end of 1999. Hybridon is currently evaluating all of its internal computer
systems and microprocessors in light of the Y2K problem. As part of this
process, Hybridon has conducted an inventory of its automated instruments and
other computerized equipment and is contacting applicable vendors for
information regarding Y2K compliance. Hybridon will then upgrade or otherwise
modify its internal computer systems and microprocessors, to the extent
necessary. Testing of all its internal computer systems and microprocessors have
been completed. Hybridon does not expect the cost of bringing all systems and
microprocessors into Y2K compliance to be material. Approximately 90% of
Hybridon's systems either have been found compliant or have already been brought
into compliance.

Hybridon's Y2K compliance efforts are in addition to other planned information
technology ("IT") projects. While these efforts have caused and may continue to
cause delays in other IT projects, Hybridon does not expect that any of these
delays will have a significant effect on Hybridon's business or that any of
Hybridon's other IT projects will be canceled or postponed to pay for the Y2K
upgrades.


                                       14
<PAGE>

With regard to potential supplier Y2K problems, Hybridon has compiled a list of
its critical suppliers, and has sent and received back a Y2K questionnaire from
each of them in order to permit Hybridon to ascertain the Y2K compliance status
of each. Hybridon has not yet uncovered any key supplier Y2K problems that could
have a material effect on its business. If through continued monitoring of these
suppliers Hybridon becomes aware of any such problems and is not satisfied that
those problems are being adequately addressed, it will take appropriate steps to
find alternative suppliers.

It has been acknowledged by governmental authorities that Y2K problems have the
potential to disrupt global economies, that no business is immune from the
potentially far-reaching effects of Y2K problems, and that it is difficult to
predict with certainty what will happen after December 31, 1999. Consequently,
it is possible that Y2K problems will have a material effect on Hybridon's
business even if Hybridon takes all appropriate measures to ensure that it and
its key suppliers are Y2K compliant.

It is possible that the conclusions reached by Hybridon from its analysis to
date will change, which could cause Hybridon's Y2K cost estimates and target
completion dates to change.

SAFE HARBOR FOR FORWARD-LOOKING STATEMENTS

Statements contained in this Report on Form 10-Q may constitute "forward-looking
statements" within the meaning of Section 27A of the Securities Act of 1933 and
Section 21E of the Securities Exchange Act of 1934. For this purpose, any
statements herein that are not statements of historical fact may be deemed to be
forward-looking statements. For example, the words "believes," "anticipates,"
"plans," "expects" and similar expressions are intended to identify
forward-looking statements. Such forward-looking statements are based on
management's current expectations and involve known and unknown risks,
uncertainties, and other factors which may cause the actual results, performance
or achievements of Hybridon to be materially different from any future results,
performance, or achievements expressed or implied by such forward-looking
statements. These forward looking statements are subject to a number of
uncertainties and other factors, many of which are outside Hybridon's control,
that could cause Hybridon's actual results to differ materially from those
indicated by such statements.

For a more complete discussion of the factors that could cause actual results to
differ materially from such forward looking statements, see the discussion
thereof contained under the heading "Management's Discussion and Analysis of
Financial Condition and Results of Operations - Certain Factors that May Affect
Future Results" in Hybridon's Annual Report on Form 10-K for the year ended
December 31, 1998, which information is incorporated herein by reference.
Hybridon disclaims any intention or obligation to update or revise any forward
looking statements, whether as a result of new information, future events or
otherwise.

ITEM 3.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Historically, Hybridon's primary exposures have been related to
nondollar-denominated operating expenses in Europe. As of September 30, 1999,
Hybridon's assets and liabilities related to nondollar-denominated currencies
were not material.


                                       15
<PAGE>

                                 HYBRIDON, INC.

                                     PART II

                                OTHER INFORMATION


ITEM 1.  LEGAL PROCEEDINGS

         None.

ITEM 2.  CHANGES IN SECURITIES AND USE OF PROCEEDS

         None.


ITEM 3.  DEFAULTS UPON SENIOR SECURITIES

         None.


ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

         None.


ITEM 5.  OTHER INFORMATION

         On September 23, 1999, Hybridon lifted the contractual "lock-up"
         provision concerning the sale of common stock acquired by certain
         investors in May 1998.

         On September 7, 1999, Hybridon entered into a non-exclusive license
         agreement with Genzyme Molecular Oncology, a division of Genzyme
         Corporation ("Genzyme"). Under the license agreement, Hybridon obtained
         a non-exclusive license to patent rights relating to antisense
         compounds that interfere with the expression of MDM2, a cancer-related
         protein, methods for treating cancers with these compounds, and methods
         for identifying these compounds. These patent rights are exclusively
         licensed to Genzyme by the Johns Hopkins University. In exchange for
         the patent rights, Genzyme received an up-front payment. If Hybridon
         successfully develops therapeutic products through the use of these
         rights, Genzyme will receive significant milestone payments and royalty
         payments on product sales.


ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

(a)      Exhibits

         10.1     Licensing Agreement dated September 7, 1999, between Genzyme
                  Corporation and Hybridon, Inc.

         10.2     Form of loan agreement relating to a loan in the amount of
                  $454,901 made to Hybridon, Inc. in October 1999 by various
                  parties.

         10.3     Form of promissory note relating to a loan in the amount of
                  $454,901 made to Hybridon, Inc. in October 1999 by various
                  parties.


                                       16
<PAGE>

         10.4     Loan Agreement dated as of September 1, 1999, between
                  Hybridon, Inc. and E. Andrews Grinstead III.

         10.5     Term promissory note in the amount of $500,000 dated September
                  1, 1999, by Hybridon, Inc. in favor of E. Andrews Grinstead
                  III.

         10.6     Term promissory note in the amount of $500,000 dated September
                  27, 1999, by Hybridon, Inc. in favor of E. Andrews Grinstead
                  III.

         27.1     Financial Data Schedule (EDGAR)

(b)      No current reports on Form 8-K were filed during the three months ended
September 30, 1999.

                                       17
<PAGE>

                                   SIGNATURES

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

                                 HYBRIDON, INC.


November 15, 1999                     /s/ E. Andrews Grinstead, III
- -----------------                    ---------------------------------------
Date                                 E. Andrews Grinstead, III
                                     Chairman, President and Chief Executive
                                     Officer (Principal Executive Officer)


November 15, 1999                    /s/ Robert G. Andersen
- -----------------                    ----------------------
Date                                 Robert G. Andersen
                                     Treasurer (Principal Financial and
                                     Accounting Officer)


                                       18
<PAGE>

                                 HYBRIDON, INC.

                                 EXHIBIT INDEX


10.1     Licensing Agreement dated September 7, 1999, between Genzyme
         Corporation and Hybridon, Inc.

10.2     Form of loan agreement relating to a loan in the amount of $454,901
         made to Hybridon, Inc. in October 1999 by various parties.

10.3     Form of promissory note relating to a loan in the amount of $454,901
         made to Hybridon, Inc. in October 1999 by various parties.

10.4     Loan Agreement dated as of September 1, 1999, between Hybridon, Inc.
         and E. Andrews Grinstead III.

10.5     Term promissory note in the amount of $500,000 dated September 1, 1999,
         by Hybridon, Inc. in favor of E. Andrews Grinstead III.

10.6     Term promissory note in the amount of $500,000 dated September 27,
         1999, by Hybridon, Inc. in favor of E. Andrews Grinstead III.

27.1     Financial Data Schedule (EDGAR)


                                       19


          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

                                                                    Exhibit 10.1

                                LICENSE AGREEMENT

      THIS LICENSE AGREEMENT dated as of September 7, 1999 (the "Agreement") is
made between Hybridon Inc., a corporation organized under the laws of the State
of Delaware ("Hybridon"), and Genzyme Corporation, a corporation organized under
the laws of the Commonwealth of Massachusetts ("Genzyme"). Hybridon and Genzyme
are sometimes referred to herein individually as a "Party" and collectively as
the "Parties."

                                 R E C I T A L S

      A. Genzyme controls certain patents and patent applications relating to
MDM2 through a license agreement (the "JHU Agreement") dated February 5, 1992
among The Johns Hopkins University ("JHU"), Hoffmann-La Roche Inc. and Genzyme
as the successor in interest through the merger of PharmaGenics, Inc. with and
into Genzyme.

      B. Genzyme has the right, subject to rights retained by the U.S.
government and by JHU, to sublicense certain patents and patent applications
relating to inhibitory compounds that interfere with the expression of the MDM2
gene, to methods for treating a neoplastic cell or a cell having neoplastic
potential through the administration of such compounds, and to methods to
identify such compounds.

      C. Subject to the terms and conditions of this Agreement, Genzyme is
willing to grant and Hybridon wishes to receive a non-exclusive sublicense under
such patents and patent applications to make, use and sell Licensed Products (as
herein defined) throughout the world.

      NOW THEREFORE, in consideration of the premises and of the covenants
herein contained, the Parties mutually agree as follows:

                             ARTICLE 1. DEFINITIONS

      For purposes of this Agreement, the terms defined in this Article shall
have the meanings specified below. Certain other capitalized terms are defined
elsewhere in this Agreement.

      1.1. "Affiliate" shall mean any corporation or other entity which
controls, is controlled by, or is under common control with a Party. A
corporation or other entity shall be regarded as in control of another
corporation or entity if it owns or directly or indirectly controls more than
fifty percent (50%) of the voting stock or other ownership interest of the other
corporation or entity, or if it possesses, directly or indirectly, the power to
direct or cause the direction of the management

<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

and policies of the corporation or other entity or the power to elect or appoint
more than fifty percent (50%) of the members of the governing body of the
corporation or other entity.

      1.2. "Antisense Technology" shall mean the selective inhibition of protein
synthesis at the RNA level. This inhibition is caused by the hybridization of an
Oligonucleotide to the complementary sequence of the selected RNA thereby
inhibiting gene expression.

      1.3. "Collaborative Partner" shall mean a Third Party with which Hybridon
enters into an agreement providing for the development and/or commercialization
of a Development Candidate.

      1.4. "Compound" shall mean ***

      1.5. "Development Candidate" shall mean ***

      1.6. "Effective Date" shall mean the date appearing on the cover page of
this Agreement.

      1.7. "First Commercial Sale" shall mean the first transfer of title to a
Licensed Product by Hybridon, its Affiliates or a Collaborative Partner to a
non-Affiliate for consideration in any arm's length transaction in a country
following governmental approval for commercial sale in such country. For the
purpose of this definition a transfer of title to reasonable quantities of free
samples of Licensed Product or to clinical trial material shall not constitute a
First Commercial Sale.

      1.8. "FDA" shall mean the United States Food and Drug Administration, any
successor agency, or the regulatory authority of a Major Country other than the
United States with responsibilities comparable to those of the United States
Food and Drug Administration.

      1.9. "IND" shall mean the regulatory filing required to initiate human
clinical trials in the United States or any other Major Country. If human
clinical trials are initiated without a requirement for regulatory filing or
approval, an IND shall be deemed to have been filed on the initiation of human
clinical trials.

      1.10. "Licensed Method" shall mean ***

      1.11. "Licensed Product" shall mean ***

      1.12. "Major Country" shall mean Germany, France, United Kingdom, the
United States, or Japan.


                                       2
<PAGE>

      1.13. "NDA" shall mean a New Drug Application, as defined in the United
States Food, Drug and Cosmetic Act, or any corresponding foreign application,
registration or certification.

      1.14. "Net Sales" shall mean that the gross amount invoiced on sales or
other dispositions of a Licensed Product by Hybridon and its Affiliates and
Collaborative Partners, as applicable, to independent third parties, less the
following items (provided that such items are included in the amount invoiced
and do not exceed reasonable and customary amounts in the country in which such
sale or other disposition occurred): (i) trade, cash, quantity and promotional
discounts actually allowed and taken; (ii) excises, sales taxes or other taxes
imposed upon and paid with respect to such sales (excluding national, state or
local taxes based on income); (iii) freight, insurance and other transportation
charges incurred in shipping a Licensed Product to third parties; (iv) amounts
repaid or credited by reason of rejections, defects, recalls or returns; and (v)
rebates (including pursuant to Medicaid or other governmental programs). Such
amounts shall be determined from the books and records of Hybridon and its
Affiliates and Collaborative Partners, and maintained in accordance with GAAP.
If a Licensed Product is sold, leased, used or otherwise commercially disposed
of for value (including, without limitation, disposition in connection with the
delivery of other products or services) in a transaction that is not an arm's
length sale to an independent third party, then the gross amount invoiced in
such transaction shall be deemed to be the gross amount that would have been
paid had there been such a sale at the average sale price of such Licensed
Product during the applicable royalty reporting period. Net Sales shall also
include any consideration received by Hybridon and its Affiliates and
Collaborative Partners in respect of the sale, use or other disposition of a
Licensed Product in a country prior to the receipt of all regulatory approvals
required to commence full commercial sales of such Licensed Product in such
country (e.g., sales under " treatment INDs", "named patient sales",
"compassionate use sales", or their equivalents), other than the sale, use or
other disposition of such Licensed Product in the course of any clinical trial
conducted with respect to such Licensed Product.

      1.15. "Oligonucleotide" shall mean an oligomer or polymer made up of at
least six nucleosides or nucleotides. Oligonucleotide includes RNA or DNA
fragments. Oligonucleotides also include mimetics of RNA or DNA that are
composed of naturally occurring and/or non-naturally occurring bases. In
addition, an oligonucleotide may include modified and/or non-naturally occurring
sugars and/or intersugar linkages or the sugars may be partially or completely
absent. Oligonucleotides include structures where adjacent nucleosides are
linked together by phosphate groups and/or modified or non-natural
internucleoside linkages, including, without limitation, amide linkages to form
the internucleoside backbone of the oligonucleotide whether or not such linkages
retain a phosphorus atom in the linkage. A nucleotide is a nucleoside that
includes a phosphate group covalently linked to the sugar portion of the
nucleoside.

      1.16. "Patent Rights" shall mean ***


                                       3
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

      1.17. "Phase II Clinical Trial" shall mean the initial clinical testing of
a Compound in humans who are patients with a medical condition for which the
Compound is being tested with the intention of gaining a preliminary assessment
of the efficacy of a Compound in treating such medical condition. If the initial
clinical testing of a Compound in humans is in patients with a medical condition
for which the Compound is being tested, such testing shall not be deemed a Phase
II Clinical Trial unless such testing is followed by a Pivotal Quality Clinical
Trial (as herein defined).

      1.18. "Pivotal Quality Clinical Trial" shall mean a human clinical trial
of a Compound designed to be of a size and statistical significance to support
an NDA filing alone or in combination with other studies. If it is unclear
whether or not a study design will be sufficient to support an NDA filing (other
than by virtue of the uncertainty of efficacy data from that trial), the study
will be deemed to be a Pivotal Quality Clinical Trial on the initiation of
activities to support an NDA filing. Initiation of a Phase III clinical study
will be deemed to be initiation of a Pivotal Quality Clinical Trial.

      1.19. "Third Party" shall mean any entity other than Hybridon, Genzyme,
their respective Affiliates or Collaborative Partners.

                            ARTICLE 2. LICENSE GRANTS

      2.1. License. Subject to the terms and conditions of this Agreement,
Genzyme hereby grants to Hybridon and its Affiliates a nonexclusive, worldwide,
royalty-bearing sublicense under the Patent Rights to discover, develop, make,
have made, use, import and export, offer for sale, and sell Licensed Products
including the right to develop, make, have made and use the Licensed Methods.
Such sublicense shall not include the right to grant sublicenses except under
the circumstances set forth in Section 2.3.

      2.2. Limitations. The Licenses granted under this Article 2 are subject
to:

            (a) the rights retained by the United States government in
accordance with P.L. 96-517, as amended by P.L. 98-620,

            (b) the retained rights of JHU to make, have made, provide and use
any method, product or composition which is covered by the Patent Rights for its
and The Johns Hopkins Health Systems' ("JHHS") non-profit purposes, and

            (c) all rights of Genzyme relating to Patent Rights not specifically
licensed to Hybridon under this Agreement, as further set forth in Section 2.1.


                                       4
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

      2.3. Right to Sublicense to Collaborative Partners. *** Any Collaboration
Agreement shall be consistent with the terms and conditions of this Agreement.
Any and all Collaboration Agreement entered into by Hybridon pursuant to Section
2.3 shall expressly: (I) prohibit Collaborative Partner(s) from granting
sublicenses (except as permitted above) and (ii) require Collaborative
Partner(s) to accord confidential treatment to Confidential Information
consistent with the terms and conditions of Article 6. It is expressly agreed by
the Parties that Hybridon shall remain responsible for compliance with the terms
of this Agreement. Furthermore, it is understood and agreed that this Section
2.3 shall not give Hybridon, its Affiliates or Collaborative Partners a right to
grant sublicenses other than as provided herein.

      2.4. No Other Technology Rights. Except as otherwise expressly provided in
this Agreement, under no circumstances shall a Party hereto, as a result of this
Agreement, obtain any ownership interest in or other right to the patent rights,
inventions, trade secrets, copyrights, know-how, data or other intellectual
property of the other Party, including items owned, controlled or developed by
any Third Party, or transferred by one Party to the other Party at any time
pursuant to this Agreement.

      2.5. Favored Licensee. Genzyme represents and warrants that it has not
granted a license to a commercial Third Party under the Patent Rights on
financial terms and conditions which are, taken as a whole, more favorable to
such Third Party than those set forth in this Agreement. In the event that
Genzyme grants a sublicense to a commercial Third Party under the Patent Rights
relating to Oligonucleotides, pursuant to an agreement, the financial terms and
conditions of which are, taken as a whole, more favorable to such Third Party
than the terms and conditions of this Agreement, Genzyme shall offer Hybridon an
option to amend this Agreement to substitute the terms and conditions of such
more favorable agreement for the terms and conditions of this Agreement.
Hybridon shall make an election to accept the terms and conditions of such more
favorable agreement by providing written notice to Genzyme within thirty (30)
days after being notified of such more favorable agreement. For purposes of this
Section 2.5, the term "financial terms and conditions" shall include, but not be
limited to, the payment provisions set forth in Section 3.4 and the provisions
regarding infringement and damages set forth in Article 5 hereof.


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                               ARTICLE 3. PAYMENTS

         3.1.     License Fee.  ***

         3.2.     Milestone Payments.

                  3.2.1. Milestone Payments. In addition to the amounts set
forth in Sections 3.1 and 3.3, Hybridon agrees to pay to Genzyme the following
amounts upon achievement by Hybridon, its Affiliates or Collaborative Partners
of each of the following milestones with respect to a Licensed Product:

           Milestone                                                Amount


   ***                                                      ***

   ***                                                      ***


   ***                                                      ***

   ***                                                      ***

   ***                                                      ***

***

            3.2.2. Notice; Payments Due. Hybridon shall promptly notify Genzyme
in writing of the achievement of any milestone identifying the date in which it
occurred. All payments due to Genzyme from Hybridon pursuant to Section 3.2.1
shall be made within forty-five (45) days after the achievement of the
corresponding milestone and are not refundable under any circumstances or
creditable against any other amounts due Genzyme under this Agreement.

      3.3. Royalties; Reports.

         (a)      ***

         (b)      ***

         (c)      Hybridon shall notify Genzyme in writing of the First
                  Commercial Sale within thirty (30) days after such sale.


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            (d) Hybridon agrees that beginning with the calendar quarter in
which the First Commercial Sale occurs, Genzyme shall receive, within sixty (60)
days after the end of such calendar quarter, and each of the first three
calendar quarters thereafter, and within ninety (90) days after the end of each
calendar year end thereafter: (i) payment of royalties and (ii) a written report
showing the information and basis on which the royalties have been calculated;
provided, however, that if the First Commercial Sale occurs in the fourth
calendar quarter, the first such payment and report shall be made within ninety
(90) days after the end of such calendar quarter.

            (e) In the event the Licensed Product is sold as part of a
Combination Product (as defined below), the Net Sales from the Combination
Product, for the purposes of determining royalty payments, shall be determined
by multiplying the Net Sales of the Combination Product (as defined in the
standard Net Sales definition), during the applicable royalty reporting period,
by the fraction, A/A+B where A is the average sale price of the Licensed Product
when sold separately in finished form and B is the average sale price of the
other active compound(s) and/or ingredient(s) included in the Combination
Product when sold separately in finished form, in each case during the
applicable royalty reporting period or, if sales of both the Licensed Product
and the other Product (s) did not occur in such period, then in the most recent
royalty reporting period in which sales of both occurred. In the event that such
average sale price can not be determined for both the Licensed Product and all
other product (s) included in the Comination Product, Net Sales for the purposes
of determining royalty payments shall be calculated by multiplying the Net Sales
of the Combination Product by the fraction C/C+D where C is the fair market
value of the Licensed Product and D is the fair market value of all other active
compound(s) and/or ingredient(s) included in the Combination Product. As used
above, the term "Combination Product" means any pharmaceutical product which
comprises the Licensed Product and other active compound(s) and/or
ingredient(s).

            (f) During any period in which a Licensed Product is under
development or is being manufactured or commercialized by Hybridon, its
Affiliates or Collaborative Partners, as applicable, Hybridon shall deliver to
Genzyme written reports within sixty (60) days of the end of each calendar year
providing a brief description of the status of research and development
activities as well as of any manufacturing and commercializing activities, if
any, conducted with respect to such Licensed Products. Such reports shall
contain sufficient information to allow Genzyme to monitor Hybridon's compliance
with this Agreement and to enable Genzyme to satisfy its reporting obligations
to JHU under Section 4.11 of the JHU Agreement, including without limitation the
accomplishment of the milestones set forth in Section 3.2. All reports and
information provided under this Section 3.3(f) shall be subject to Article 6.

      3.4. Payments. All payments due under this Article 3 shall be made in
United States dollars by bank wire transfer in immediately available funds to an
account designated by Genzyme. If any payments are not made by Hybridon on or
before the specified due date, Hybridon will pay interest on the outstanding
amounts until paid in full, to the extent permitted


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by applicable law, in an amount equal to and fluctuating with the prime rate, as
reported by BankBoston, N.A., Boston, Massachusetts, from time to time until
such payment is made.

            (a) The license fee, milestone payments and royalties required under
Sections 3.1., 3.2., and 3.3. shall be exclusive of any applicable withholding,
value added, sales, or other taxes and duties (which, if eligible, will be paid
by Hybridon in addition to such payments).

            (b) The license fee, milestone payments and royalties payable by
Hybridon under Sections 3.1., 3.2., and 3.3. will be paid free and clear of, and
without deduction for and on account of tax, unless Hybridon is required by law
to make those payments subject to deduction or withholding of tax, in which case
the sum paid by Hybridon shall be increased to the extent necessary to ensure
that after such deduction or withholding, Genzyme receives an amount equal to
the sum which it would have received had not deduction or withholding been
required. Where Hybridon is required by law to deduct or withhold on account of
tax, it shall use commercially reasonable efforts to obtain from the relevant
revenue authorities authorization to make payment of the sums without such
deduction or withholding. The Parties undertake to provide all reasonable
assistance to each other in obtaining such authorization and, without prejudice
to the generality of the foregoing, will submit any forms or take any action as
may be reasonably necessary or reasonably requested by the other Party for that
purpose.

            (c) If Hybridon is required to increase the amount of any payment
under the provisions of Section 3.4.(b) as a result of any withholding or
deduction required by law and Genzyme receives any amount by way of repayment of
the tax that is so deducted or withheld by Hybridon, Genzyme will reimburse,
without interest, to Hybridon an amount equal to such repayment.

            (d) Subsections (a), (b) and (c) of this Section 3.4 will apply
equally to any royalties and other amounts payable under Section 3.3 if Genzyme
directs Hybridon to pay those royalties or other amounts directly to a Third
Party.

            (e) If the Net Sales is in a currency other than U.S. Dollars (a
"Foreign Currency Amount"), then, for the purpose of determining the amount of
royalties payable hereunder, such Foreign Currency Amount shall be converted
into U.S. Dollars at the exchange rate between those two currencies quoted in
the Wall Street Journal (Eastern Edition) five (5) business days immediately
preceding the date on which such royalties become due. If no such exchange rate
is quoted in that edition, such payment shall be converted into U.S. Dollars at
the exchange rate between those two currencies most recently quoted in the Wall
Street Journal (Eastern Edition). If no such exchange rate has been quoted in
the Wall Street Journal (Eastern Edition) at any time during the twelve (12)
month period preceding the date on which royalties become due, such Foreign
Currency Amount which relates to Net Sales shall be deemed to be


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equal to the Net Sales most recently charged by the receiving party in a sale of
such Product in U.S. Dollars.

      3.5. Records; Audit. Hybridon shall keep, and maintain complete and
accurate records of its sales of Licensed Products in accordance with United
States generally accepted accounting principles, consistently applied. Hybridon
shall require each of its Affiliates and Collaborative Partners to keep and
maintain complete and accurate records of any sale of Licensed Products. Such
records shall be retained for a period of four (4) years following the
applicable royalty reporting period. Hybridon shall permit, and cause each of
its Affiliates and Collaborative Partners to permit, independent accountants
retained by Genzyme to have access to its records and books for the sole purpose
of verifying Net Sales and any royalty due thereon. Such examination shall be
conducted during regular business hours and upon reasonable notice, at the
auditing Party's own expense and no more than once in each calendar year during
the term of this Agreement and once during the four (4) calendar years following
the termination hereof. Any adjustment in the amount of royalties due Genzyme on
account of overpayment or underpayment of royalties shall be made at the next
date when royalty payments are to be made to Genzyme under Section 3.4. Genzyme
shall pay the fees and expenses of the accountant engaged to perform the audit,
unless such audit reveals an underpayment of seven and one-half percent (7.5%)
or more for the period examined, in which case Hybridon shall pay all reasonable
costs and expenses incurred by Genzyme in the course of making such
determination, including the fees and expenses of the accountant (i.e., if
Hybridon pays "X" in royalties and an audit reveals it should have paid "Y" (the
difference, Y-X, being "Z"), then the underpayment percentage equals the product
obtained by multiplying (i) the quotient obtained by dividing Z and Y (Z /Y) and
(ii) 100).

                   ARTICLE 4. REPRESENTATIONS, WARRANTIES AND
                             LIMITATIONS; COMPLIANCE

      4.1. Authorization. Each Party warrants and represents to the other that
it has the legal right and power to enter into this Agreement, to extend the
rights granted to the other in this Agreement, and to perform fully its
obligations hereunder, and that this Agreement is a valid and binding agreement
of such Party, enforceable in accordance with its terms.

      4.2. Patent Rights Representations, Warranties and Limitations.

            (a) Genzyme represents and warrants that, as of the Effective Date:

                  (i) it has not made nor will it make any commitments to others
      in conflict with or in derogation of the rights created by this Agreement;


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                  (ii) to the best of its knowledge, all obligations under 37
      C.F.R.ss.1.56 have been satisfied for all patents and patent applications
      within the Patent Rights;

                  (iii) the statements set forth in the letter from JHU attached
      hereto as Appendix B are true and correct; and

                  (iv) to the best of its knowledge, there are no pending third
      party patent applications that could form a reasonable basis for a U.S.
      interference proceeding with the Patent Rights.

            (b) Except as otherwise provided herein, nothing herein contained
shall be construed as:

                  (i) a representation or warranty by Genzyme as to the validity
      or scope of any sublicensed Patent Rights;

                  (ii) a representation or warranty that any Licensed Product
      discovered, developed, made, used, imported, exported, sold or otherwise
      disposed of under the sublicense granted in this Agreement is or will be
      free from infringement of patents, copyrights, or trademarks of Third
      Parties; or

                  (iii) an express or implied warranty of merchantability or
      fitness for a particular purpose.

            (c) In no event will Genzyme or its Affiliates be liable for
damages, whether direct, indirect, special, punitive, incidental or
consequential, or otherwise in relation to any Licensed Products manufactured or
sold by Hybridon, its Affiliates, Collaborative Partners or any distributor.
Neither Genzyme nor its Affiliates shall be obligated to defend or hold harmless
Hybridon, its Affiliates, Collaborative Partners or any other person against any
suit, damage, claim, or demand based on actual or alleged infringement of any
patent or other rights owned by a Third Party, or any unfair trade practice
resulting from the exercise or use of any right or sublicense granted under this
Agreement.

            (d) Hybridon will be solely responsible for all guarantees,
warranties, conditions, and any representations provided to distributors,
customers and end-users in relation to Licensed Products.

      4.3. Compliance. Hybridon shall comply, and shall require its Affiliates
and Collaborative Partners to comply, with all applicable laws and regulations
relative to the development, manufacture and marketing of Licensed Products.


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              ARTICLE 5. PATENT RIGHTS MAINTENANCE AND INFRINGEMENT

      5.1. Prosecution. Subject to the terms of the JHU Agreement, Genzyme shall
have the exclusive right to apply for, seek issuance of, maintain, or abandon,
any or all of the Patent Rights. In the event that Genzyme receives notice from
JHU that any of the Patent Rights will revert to JHU pursuant to Section 5.1(a)
of the JHU Agreement, Genzyme shall promptly forward such notice to Hybridon.

      5.2. Infringement by Third Parties. Each Party shall promptly notify the
other of its knowledge of any potential infringement of the Patent Rights by a
Third Party.

            (a) Legal Action by Genzyme. Genzyme has the right, but not the
obligation, at its sole discretion to bring legal action against a Third Party
that it has reasonably determined to have or is infringing its Patent Rights. If
Genzyme should bring an action pursuant to this Section 5.2, to recover damages
including lost profits or reasonable royalties or injunctive relief, any
recovery of monetary damages shall be applied in the following manner: (i) first
Genzyme shall recover all lost profits or reasonable royalties, whichever is
appropriate; (ii) second Genzyme shall be reimbursed for all out-of-pocket costs
and expenses associated with obtaining injunctive relief; and (iii) Genzyme
shall be reimbursed for all other out-of-pocket litigation costs or expenses
through appeal. Once (i), (ii), and (iii) above have been satisfied in full, any
remaining recoveries or reimbursements shall be applied to reimburse Hybridon
for its lost profits based on the market share of Hybridon, its Affiliates and
Collaborative Partner(s), as applicable.

            (b) Legal Action by Hybridon. If within ninety (90) days following
receipt of notice from Hybridon setting forth Hybridon's basis to reasonably
conclude that Genzyme's Patent Rights are being infringed or have been
infringed, or such time as Genzyme otherwise becomes aware of an alleged
infringement and Genzyme has not either terminated such infringement or
initiated legal action against the infringer or defendant, Genzyme shall, upon
written request by Hybridon and with the consent of JHU (which Genzyme shall use
reasonable efforts to secure), grant to Hybridon the right (but not the
obligation) to bring an action against such infringer. In the event that
Hybridon brings such action against a Third Party for infringement of the Patent
Rights, pursuant to this Section 5.2, to recover damages including lost profits
or reasonable royalties or injunctive relief, any recovery of monetary damages
shall be applied in the following manner: (i) first if such action results in
Genzyme being a party in the action, Hybridon shall reimburse Genzyme for all
out-of-pocket costs and expenses incurred through appeal; (ii) second Hybridon
shall recover all out-of-pocket costs and expenses incurred through appeal; and
(iii) Hybridon shall recover all lost profits or reasonable royalties, whichever
is appropriate. Any recovery by Hybridon under (iii) above, shall be used in the
first instance to fulfill Hybridon's payment obligations under Article 3, which
obligations shall be based upon


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lost Net Sales of Licensed Products which formed the basis for awarding such
lost profits or reasonable royalties.

      5.3. Infringement of Third Party Rights. Hybridon shall promptly advise
Genzyme in writing of any notice or claim of any infringement and of the
commencement of any suit or action for infringement of a Third Party patent made
or brought against Hybridon, its Affiliates or Collaborative Partners and based
upon the manufacture, use, import and export, and sale or offer to sell of
Licensed Products or the practice of Licensed Methods pursuant to the sublicense
granted under the Agreement. In such event, Hybridon shall have at all times the
right to immediately cease commercialization and/or the right either to:

                  (i) request that Genzyme enter into negotiations with such
      Third Party to obtain rights for Hybridon under the Third Party patent;

                  (ii) request that Genzyme defend such claim, suit or action at
      Genzyme's expense; or

                  (iii) terminate this Agreement.

Genzyme shall not be obligated to enter into negotiations with such Third Party
to obtain rights for Hybridon under the Third Party patent nor obligated to
defend such claim, suit or action. If Genzyme, in its sole discretion, elects to
enter into negotiations with such Third Party to obtain rights for Hybridon
under the Third Party patent or if Genzyme, in its sole discretion, elects to
undertake at its own expense the defense of any such claim, suit or action,
Hybridon shall render Genzyme all reasonable assistance that may be required by
Genzyme in the negotiations or in the defense of such claim, suit or action.
Genzyme has the primary right to control the defense of any such claim, suit or
action by counsel of its own choice, and Hybridon shall have the right, at its
own expense, to be represented in any such claim, suit or action in respect of
which Hybridon is a defendant by counsel of its own choice. The Parties agree to
cooperate reasonably in any such defense. Notwithstanding the foregoing, if
Genzyme has not within ninety (90) days (or such lesser period of time as is
necessary to avoid entry of a default judgment against Genzyme or Hybridon) from
the date of receipt of a request from Hybridon, either entered into negotiations
with such Third Party to obtain rights for Hybridon under the Third Party patent
or initiated legal action to defend such claim, suit or action, then Hybridon
shall have the right, upon written notice to Genzyme, to enter such negotiations
or defend such claim, suit or action. Hybridon shall be entitled to deduct all
reasonable out-of-pocket costs and expenses, including legal fees, incurred in
entering into such negotiations or defending such claim, suit or action from
royalties due Genzyme after commencement of such action and until such expenses
are fully recouped by Hybridon.


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      5.4. Suit Relating to Patent Rights. Notwithstanding the provisions of
Sections 5.2(b) and 5.3 above, if at any time Hybridon receives notice of any
claim, suit or action by a Third Party relating to the Patent Rights (or the
validity, scope or enforceability thereof), Hybridon shall promptly notify
Genzyme in writing. Genzyme shall have the right, exercisable in its sole
discretion, to assume and control the defense of such claim, suit or action at
its own expense and using counsel of its own choice. Hybridon shall have the
right, at its own expense, to be represented in any such claim, suit or action
in respect of which Hybridon is a defendant by counsel of its own choice. The
Parties agree to cooperate reasonably in any such defense. If, however, Genzyme
has not within ninety (90) days from the date of receipt of notice from
Hybridon, either entered into negotiations with such Third Party or initiated
legal action to defend such claim, suit or action, then Hybridon shall have the
right, upon written notice to Genzyme, to enter such negotiations or defend such
claim, suit or action. Hybridon shall be entitled to deduct all reasonable
expenses, including legal fees, incurred in entering into such negotiations or
defending such claim, suit or action from royalties due Genzyme after
commencement of such action and until such expenses are fully recouped by
Hybridon. Hybridon shall not settle or compromise any such claim, suit or action
without the written consent of Genzyme, which consent shall not be unreasonably
withheld or delayed.

                           ARTICLE 6. CONFIDENTIALITY

      6.1. Confidential Information.

            (a) As used in this Agreement, the term "Confidential Information"
means any technical or business information furnished by one Party ("Disclosing
Party") to the other Party ("Receiving Party") in connection with this Agreement
and specifically designated as confidential. Such Confidential Information may
include, without limitation, the trade secrets, know-how, inventions,
formulations, compositions, technical data or specifications, testing methods,
business or financial information, research and development activities, product
and marketing plans, and customer and supplier information. Confidential
Information that is disclosed in writing shall be marked with the legend
"CONFIDENTIAL". Confidential Information that is disclosed orally or visually
shall be documented in a written notice prepared by the Disclosing Party and
delivered to the Receiving Party within thirty (30) days of the date of
disclosure. Such notice shall summarize the Confidential Information disclosed
to the Receiving Party and reference the time and place of disclosure.

            (b) The Receiving Party shall and shall cause its employees engaged
in the performance of this Agreement to: (a) maintain all Confidential
Information in strict confidence, except that the Receiving Party may disclose
or permit the disclosure of any Confidential Information to its directors,
officers, employees, consultants, and advisors who are obligated to maintain the
confidential nature of such Confidential Information and who need to know such
Confidential Information to perform this Agreement; (b) use all Confidential
Information solely


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for purposes performing this Agreement; and (c) reproduce the Confidential
Information only to the extent necessary to perform this Agreement, with all
such reproductions being considered Confidential Information.

            (c) The obligations of the Receiving Party under Section 6.1(b)
shall not apply to Confidential Information to the extent that the Receiving
Party can demonstrate by written documentation that such applicable Confidential
Information: (a) was in the public domain prior to the time of its disclosure
under this Agreement; (b) entered the public domain after the time of its
disclosure under this Agreement through means other than an unauthorized
disclosure resulting from an act or omission by the Receiving Party; (c) was
independently developed or discovered by the Receiving Party after the time of
its disclosure under this Agreement; (d) is or was disclosed to the Receiving
Party at any time, whether prior to or after the time of its disclosure under
this Agreement, by a Third Party having no fiduciary relationship with the
Disclosing Party and having no obligation of confidentiality with respect to
such Confidential Information; or (e) is required to be disclosed to comply with
applicable laws or regulations, or with a court or administrative order,
provided that the Disclosing Party receives, to the extent practicable, prior
written notice of such disclosure and that the Receiving Party takes all
reasonable and lawful actions to obtain confidential treatment for such
disclosure and, if possible, to minimize the extent of such disclosure.

            (d) Upon the termination by either Party of this Agreement, the
Receiving Party shall return to the Disclosing Party all originals, copies, and
summaries of documents, materials, and other tangible manifestations of
Confidential Information in the possession or control of the Receiving Party,
except for one copy which may be kept in the Receiving Party's legal archives.
The obligations set forth in this Agreement shall remain in effect for a period
of five (5) years after receipt of the Confidential Information by the Receiving
Party.

            (e) The Receiving Party agrees that any breach of its obligations
under this Section 6.1 may cause irreparable harm to the Disclosing Party;
therefore, the Disclosing Party shall have, in addition to any remedies
available at law, the right to seek equitable relief to enforce this Agreement.

      6.2. Terms of this Agreement. The Parties agree that the public
announcement of the execution of this Agreement shall be in the form of a
mutually acceptable press release and, from and after the publication date of
such press release, each Party shall be entitled to make or publish any
statement limited to the contents of such press release. The Parties further
agree to seek confidential treatment for the filing of this Agreement with the
Securities and Exchange Commission, if such filing is required, and shall agree
upon the content of the request for confidential treatment made by each Party in
respect of such filing. Except as permitted by the foregoing provisions or as
otherwise required by law, Hybridon and Genzyme each agree not to disclose any
terms or conditions of this Agreement to any Third Party without the prior
consent


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of the other Party; provided, however, that (i) Genzyme shall have the right to
provide a copy of this Agreement to JHU and (ii) Hybridon shall have the right
to provide a copy of this Agreement to Collaborative Partner(s) which have
agreed to treat this Agreement as Confidential Information under this Article 6.

                    ARTICLE 7. INDEMNIFICATION AND INSURANCE

      7.1. Hybridon Indemnity Obligations. Hybridon agrees to defend, indemnify
and hold Genzyme, its Affiliates and their respective directors, officers,
employees and agents and their respective successors, heirs and assigns, and
JHU, JHHS and its subsidiary corporations, their present and former trustees,
officers, inventors of Patent Rights, agents, faculty, employees, students,
treating and consulting physicians harmless from and against any losses, costs,
claims, damages, liabilities or expenses (including reasonable attorneys' and
professional fees and other expenses of litigation) (collectively,
"Liabilities") arising, directly or indirectly, out of or in connection with
Third Party claims, suits, actions, demands or judgments, including, without
limitation, personal injury and product liability matters, suits, actions, or
demands relating to (i) any Licensed Product developed, manufactured, used, sold
or otherwise distributed by or on behalf of Hybridon, its Affiliates,
Collaborative Partners, or other designees (including without limitation,
product liability claims) or (ii) the use of the Patent Rights by or on behalf
of Hybridon, its Affiliates, Collaborative Partners or other designees, except
in each case, to the extent such Liabilities resulted from a material breach of
this Agreement by Genzyme or negligence or intentional misconduct on the part of
Genzyme.

         7.2. Insurance. Hybridon, its Affiliates or Collaborative Partner(s)
shall maintain appropriate product liability insurance or self-insurance with
respect to the development, manufacture and sale of Licensed Products by
Hybridon, its Affiliates, Collaborative Partner(s) or other designees in such
amount as such entity customarily maintains with respect to the development,
manufacture and sale of its other products. Hybridon, its Affiliates or
Collaborative Partner(s) shall maintain such insurance for so long as it
continues to manufacture or sell the Licensed Products and shall name Genzyme,
JHU, and JHHS as additional insureds, and thereafter for so long as such entity
maintains insurance for itself covering such manufacture or sales.

                         ARTICLE 8. TERM AND TERMINATION

      8.1 Term. The term of this Agreement shall commence on the Effective Date
and continue until the expiration of all royalty obligations under Section 3.3
of this Agreement.

      8.2. Termination. This Agreement may be terminated in the following
circumstances:


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            8.2.1. For Convenience. Hybridon may terminate this Agreement at any
time upon ninety (90) days' written notice to Genzyme.

            8.2.2. Upon Breach. Upon any material breach of this Agreement by
either Party (in such capacity, the "Breaching Party"), the other Party (in such
capacity, the "Non-Breaching Party") may terminate this Agreement by providing
sixty (60) days written notice to the Breaching Party, specifying the material
breach. The termination shall become effective at the end of the sixty (60) day
period unless: (a) the Breaching Party cures such breach during such sixty (60)
day period, (b) if such breach is not susceptible to cure within sixty (60) days
of the receipt of written notice of the breach, the Breaching Party is
diligently pursuing a cure, or (c) the Breaching Party has commenced dispute
resolution pursuant to Section 9.6 prior to the expiration of the sixty (60) day
cure period (in which event, such termination shall not be effective unless the
Arbitration Panel determines that the Party in breach has materially breached or
defaulted in the performance of any of its material obligations hereunder);
provided, however, in the case of a failure to pay any amount due hereunder,
such default may be the basis of termination thirty (30) business days following
the date that notice of such default was provided to the Breaching Party.

            8.2.3. Upon Bankruptcy. Either Party may terminate this Agreement
immediately if the other Party (in such capacity, the "Bankrupt Party"): (i)
applies for or consents to the appointment of a receiver, trustee, liquidator or
custodian of itself or of all or a substantial part of its property, (ii) admits
in writing its inability to pay its debts generally as they mature, (iii) makes
a general assignment for the benefit of its creditors, (iv) is dissolved or
liquidated in full or in part, (v) commences a voluntary case or other
proceeding seeking liquidation, reorganization or other relief with respect to
itself or its debts under any bankruptcy, insolvency or other similar law now or
hereafter in effect or consents to any such relief or to the appointment of or
taking possession of its property by any official in an involuntary case or
other proceeding commenced against it, (vi) takes any action for the purpose of
effecting any of the foregoing, or (vii) becomes the subject of an involuntary
case or other proceeding seeking liquidation, reorganization or other relief
with respect to itself or its debts under any bankruptcy, insolvency or other
similar law now or hereafter in effect that is not dismissed within sixty (60)
calendar days of commencement.

            8.2.4. Accrued Rights and Obligations. Termination or expiration of
this Agreement for any reason shall not release any Party hereto from any
liability which, at the time of such termination or expiration, has already
accrued to the other Party or which is attributable to a period prior to such
termination or expiration, nor preclude either Party from pursuing any rights
and remedies it may have hereunder or at law or in equity which accrued or are
based upon any event occurring prior to such termination or expiration.


                                       16
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.


            8.2.5. Sublicenses.

                  (a) In the event that the sublicense granted under the JHU
Agreement to Genzyme is terminated, any granted sublicense to Hybridon and its
Affiliates under this Agreement shall remain in full force and effect, provided
that Hybridon and its Affiliates: (i) are not then in breach of this Agreement,
and (ii) agree to be bound to JHU as licensor under the terms and conditions of
this Agreement.

                  (b) In the event that the sublicense granted under this
Agreement to Hybridon and its Affiliates is terminated, or upon the occurrence
of any event which results in Hybridon becoming a Bankrupt Party, any granted
sublicense to Collaborative Partner(s) shall remain in full force and effect,
provided that such Collaborative Partner(s) (i) are not then in breach of their
respective Collaborative Agreement(s) and (ii) agree to be bound to Genzyme as
licensor under the terms and conditions of this Agreement.

            8.2.6. Survival. The provisions of Articles 1, 6 and 7 and Sections
3.2.2 (limited solely to the obligation to make final payment of any amounts
accrued prior to expiration or termination), 3.3 (limited solely to the
obligation to submit final report), 3.4, 3.5, 8.2.4, 8.2.5, 8.2.6, 9.4, 9.5 and
9.6 shall survive the expiration or termination of this Agreement.

                            ARTICLE 9. MISCELLANEOUS

      9.1. Force Majeure. Neither Party shall be held liable or responsible to
the other Party nor be deemed to have defaulted under or breached this Agreement
for failure or delay in fulfilling or performing any term of this Agreement when
such failure or delay is caused by or results from causes beyond the reasonable
control of the affected Party, including without limitation, fire, floods,
embargoes, war, acts of war (whether war is declared or not), insurrections,
riots, civil commotions, strikes, lockouts or other labor disturbances, acts of
God or acts, omissions or delays in acting by any governmental authority or the
other Party.

      9.2. Assignment. This Agreement may not be assigned or otherwise
transferred by any Party without the consent of the other Party; provided,
however, that each Party may, without such consent, assign its rights and
obligations under this Agreement (i) in connection with a corporate
reorganization, to any member of an affiliated group, all or substantially all
of the equity interest of which is owned and controlled by such Party or its
direct or indirect parent corporation, or (ii) in connection with a merger,
consolidation or sale of substantially all of such Party's assets to an
unrelated Third Party; provided, however, that such Party's rights and
obligations under this Agreement shall be assumed by its successor in interest
in any such transaction and shall not be transferred separate from all or
substantially all of its other business assets, including those business assets
that are the subject of this Agreement. Any purported


                                       17
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.


assignment in violation of the preceding sentence shall be void. Any permitted
assignee shall assume all obligations of its assignor under this Agreement.

      9.3. Severability. Each Party hereby agrees that it does not intend to
violate any public policy, statutory or common laws, rules, regulations, treaty
or decision of any government agency or executive body thereof of any country or
community or association of countries. Should one or more provisions of this
Agreement be or become invalid, the Parties hereto shall substitute, by mutual
consent, valid provisions for such invalid provisions which valid provisions in
their economic effect are sufficiently similar to the invalid provisions that it
can be reasonably assumed that the Parties would have entered into this
Agreement with such valid provisions. In case such valid provisions cannot be
agreed upon, the invalidity of one or several provisions of this Agreement shall
not affect the validity of this Agreement as a whole, unless the invalid
provisions are of such essential importance to this Agreement that it is to be
reasonably assumed that the Parties would not have entered into this Agreement
without the invalid provisions.

      9.4. Notices. Any consent, notice or report required or permitted to be
given or made under this Agreement by one of the Parties hereto to the other
shall be in writing, delivered personally or by facsimile (and promptly
confirmed by personal delivery or courier) or courier, postage prepaid (where
applicable), addressed to such other Party at its address indicated below, or to
such other address as the addressee shall have last furnished in writing to the
addressor and shall be effective upon receipt by the addressee.

         If to
         Hybridon:           Hybridon Inc.
                             155 Fortune Boulevard
                             Milford, Massachusetts 01757
                             Attention: Chairman, Chief Executive Officer
                             and President

         with a copy to:     Hybridon Inc.
                             155 Fortune Boulevard
                             Milford, Massachusetts 01757
                             Attention: Vice President and General Counsel

         If to               Genzyme Corporation
         Genzyme:            P.O. Box 9322
                             15 Pleasant Street Connector
                             Framingham, Massachusetts 01701-9322
                             Attention:  President, Genzyme Molecular Oncology

         with a copy to:     Genzyme Corporation
                             One Kendall Square, Building 1400
                             Cambridge, Massachusetts 02139-1562
                             Attention: Chief Legal Officer


                                       18
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

      9.5. Governing Law and Venue. The Parties hereby consent to the
jurisdiction and venue of the state and federal courts in the Commonwealth of
Massachusetts. This Agreement shall be governed by and construed under the laws
of the Commonwealth of Massachusetts, without regard to its conflicts of law
principles.

      9.6. Dispute Resolution.

            9.6.1. General. Any disputes arising between the Parties relating
to, arising out of or in any way connected with this Agreement or any term or
condition hereof, or the performance by any Party of its obligations hereunder,
whether before or after termination of this Agreement (a "Dispute"), which is
not settled by the Parties within thirty (30) days after notice of such Dispute
is given by one Party to the other in writing shall be referred to the Chief
Legal Officer of Genzyme and the Chief Executive Officer of Hybridon who are
authorized to settle such Disputes on behalf of their respective companies
("Senior Executives"). The Senior Executives will meet for negotiations within
thirty (30) days of the end of the 30-day negotiation period referred to above,
at a time and place mutually acceptable to both Senior Executives. If the
Dispute has not been resolved within thirty (30) days after the end of the
30-day negotiation period referred to above (which period may be extended by
mutual agreement), subject to any rights to injunctive relief and unless
otherwise specifically provided for herein, any Dispute will be finally resolved
by binding arbitration as provided in Section 9.6.2.

            9.6.2. Arbitration. Any arbitration hereunder shall be conducted
under the commercial rules of the American Arbitration Association. Each such
arbitration shall be conducted in the English language by a panel of three
arbitrators (the "Arbitration Panel"). Each of Hybridon and Genzyme shall
appoint one arbitrator to the Arbitration Panel and the third arbitrator shall
be appointed by the two arbitrators appointed by Hybridon and Genzyme. The
Arbitration Panel shall be convened upon delivery of written notice by one Party
to the other following expiration of the time periods provided in Section 9.6.1
that the notifying Party intends to institute arbitration proceedings. Any such
arbitration shall be held in Boston, Massachusetts. The Arbitration Panel shall
have the authority to grant specific performance, and to allocate between the
Parties the costs of arbitration in such equitable manner as it shall determine.
Judgment upon the award so rendered may be entered in any court having
jurisdiction or application may be made to such court for judicial acceptance of
any award and an order of enforcement, as the case may be.


                                       19
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

      9.7. Entire Agreement. This Agreement contains the entire understanding of
the Parties with respect to the subject matter hereof and supersedes any prior
understanding. All express or implied agreements and understandings, either oral
or written, heretofore made are expressly merged in and made a part of this
Agreement. This Agreement may be amended, or any term hereof modified, only by a
written instrument duly executed by both Parties hereto.

      9.8. Headings. The captions to the several Articles and Sections hereof
are not a part of this Agreement, but are merely guides or labels to assist in
locating and reading the several Articles and Sections hereof.

      9.9. Compliance with Law. Each Party agrees to comply with all federal,
state, and local laws and regulations applicable to the sublicenses granted
under this Agreement, including without limitation the Toxic Substances Control
Act (15 U.S.C. ss. 2601 et seq.) and implementing regulations (in particular, 40
C.F.R. ss. 720.36 [Research and Development Exemption]), the Food, Drug, and
Cosmetic Act (21 U.S.C. ss. 301 et seq.) and implementing regulations, and all
United States export laws and regulations. Each Party assumes sole
responsibility for any violation of such laws or regulations by it or any of its
Affiliates.

      9.10. Use of Genzyme's Trademarks. Hybridon agrees that it shall have no
right or license to use any trademark of Genzyme.

      9.11. Use of The Johns Hopkins University Names. Hybridon agrees that it
shall have no right or license to use the names, likeness, or logos of The Johns
Hopkins University or any of its schools or divisions of The Johns Hopkins
Health Systems or any of its constituent parts and affiliated hospitals and
companies, or any contraction or derivative thereof or the names of The Johns
Hopkins University's faculty members, employees, and students in any press
releases, general publications, advertising, marketing, promotional or sales
literature without prior written consent from an authorized official of The
Johns Hopkins University.

      9.12. Product Marking. Hybridon shall mark and shall require Affiliates
and Collaborative Partners to mark all packaging containing Licensed Products
and/or items relating to the practice of the Licensed Method with the number of
the applicable patents licensed hereunder in accordance with the laws of the
country in which such items are distributed.

      9.13. Independent Contractors. It is expressly agreed that each of the
Parties shall be independent contractors and that the relationship between the
Parties shall not constitute a partnership, joint venture or agency. No Party
shall have the authority to make any statements, representations or commitments
of any kind, or to take any action, which shall be binding on the other, without
the prior consent of the other Party to do so.


                                       20
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

      9.14. Waiver. The waiver by either Party hereto of any right hereunder or
the failure to perform or a breach by the other Party shall not be deemed a
waiver of any other right hereunder or of any other breach or failure by said
other Party whether of a similar nature or otherwise.

      9.15. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.


                                       21
<PAGE>


          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

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

                                  HYBRIDON INC.


                                      By:               (signed)
                                         -------------------------------------
                                      Name:  E. Andrews Grinstead III
                                      Title: Chairman, CEO and President

                                      GENZYME CORPORATION


                                      By:               (signed)
                                         -------------------------------------
                                      Name:    Thomas J. DesRosier
                                      Title:   Senior Vice President,
                                               Chief Patent Counsel


                                       22
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

                           Appendix A - Patent Rights


         ***


                                       23
<PAGE>

          Confidential materials omitted and filed separately with the
                       Securities and Exchange Commission.
                           Asterisks denote omissions.

                                   Appendix B


         ***

                                       24



                                 LOAN AGREEMENT


      LOAN AGREEMENT ("Agreement") dated as of October ____, 1999, is entered
into by and among HYBRIDON, INC. (the "Borrower"), a Delaware corporation having
its principal place of business at 155 Fortune Boulevard, Milford, Massachusetts
01757 and _______________________________________________________, with an
address at ________________________________________________________________,
(the "Lenders").

                              W I T N E S S E T H:

      WHEREAS, the Borrower has requested and the Lenders have agreed to make a
loan to the Borrower in an aggregate principal amount of
__________________________ Dollars and 00/100 (US$________________), the
("Loan") on the terms, and subject to the conditions set forth herein;

      NOW, THEREFORE, IT IS AGREED that, in consideration of the premises and
mutual agreements contained herein, the parties hereby agree as follows:

SECTION 1. THE LOAN.

      1.1 Loan. Subject to and upon the terms and conditions set forth herein,
Lenders agree to make the Loan to Borrower on October _______, 1999 in an
aggregate principal amount of _______________________________________________
Dollars and 00/100 (US$______________________) (the "Loan"). At the Borrower's
request, the Lenders may, but are not required to, make additional advances (up
to a maximum of an additional US$_________________) to the Borrower under this
Agreement. Any such additional advances shall also be deemed to be part of the
Loan hereunder.

      1.2 Senior Indebtedness. The Lender and the Borrower intend that the Loan
constitutes "Senior Indebtedness" under the Borrower's 9% Convertible Secured
Notes due 2004.

      1.3 Conversion of Loan. The parties agree that the Loan will be converted,
at the Lenders' option, into either (a) preferred equity, or (b) secured debt,
in each case on substantially the terms described in Exhibit A hereto, no later
than December 31, 1999 (the "Conversion"). The Lenders shall notify the Borrower
regarding which Conversion option (i.e. preferred equity or secured debt) it
elects not later than December 17, 1999. At the Borrower's request, the
Conversion may be effected prior to December 31, 1999, in which case the
Borrower shall notify the Lenders (the "Conversion Notice") at least five (5)
business days prior to the proposed Conversion date. Lenders shall have two (2)
business days from the date of the Conversion Notice to notify the Borrower
which Conversion option it elects.

<PAGE>

SECTION 2.  INTEREST RATE AND OTHER CHARGES.

      2.1 Interest. (a) Borrower shall pay the Lenders interest monthly, in
arrears, on the unpaid principal amount of the date the Conversion is effected
(the "Conversion Date") at the rate of eight per cent (8%) per annum, payable in
common stock of the Borrower at the rate of fifty cents (US$0.50) per share. Any
common stock of the Borrower issued pursuant to this Section 2.1 shall bear an
appropriate securities law legend and, at the request of Borrower, the issuance
thereof shall be subject to the Lenders' execution and delivery of an
appropriate private placement agreement.

      (b) Interest shall accrue from and including the Closing Date and to but
excluding the Conversion Date (or the date upon which the principal balance is
paid in full) and shall be payable as provided above on the first business day
of each month that the Loan is outstanding, commencing November 1, 1999 and upon
any repayment (to the extent accrued on the amount being repaid), and at the
Conversion Date.

      (c) All computations of interest hereunder shall be made on the basis of a
360-day year consisting of 12 30-day months.

      2.2 Excess Interest. In no event whatsoever shall the interest rate and
other charges charged hereunder exceed the highest rate permissible under any
law which a court of competent jurisdiction shall, in a final determination,
deem applicable hereto. In the event that a court determines that the Lenders
have received interest or other charges hereunder in excess of the highest
permissible rate applicable thereto, the Lenders shall promptly refund the
amount thereof to Borrower, and the provisions hereof shall be deemed amended to
provide for such permissible rate.

SECTION 3.  PRINCIPAL PAYMENTS AND REPAYMENTS.

      3.1 Repayment and Conversion. The Loan shall be repaid as provided in this
Section 3.1 or converted as provided in Section 1.3 above. Borrower may repay
the Loan in whole or in part without premium or penalty at any time. Repayments
of the Loan may not be re-borrowed. All repayments of the Loan or any portion
thereof shall be made together with the payment of all interest accrued on the
amount repaid through the date of such payment.

      3.2 [Reserved]

      3.3 Notices. Borrower shall give the Lenders five (5) days' prior written
notice of each repayment of the Loan or any portion thereof. Each notice of
repayment shall specify the amount of the Loan to be repaid and the date of
repayment.

      3.4 Payments Without Deductions. Borrower shall pay principal, interest,
and all other amounts payable hereunder, or under the Note, without any
deduction whatsoever, including, but not limited to, any deduction for any
setoff or counterclaims


                                      -2-
<PAGE>

whatsoever, provided that with respect to withholding taxes Borrower may make
such deductions as may be required by law if Lender fails to deliver a Form W-9
to Borrower.

SECTION 4. LEGAL EXPENSES  AND SETOFF

      4.1 (a) The Borrower agrees to pay on demand reasonable attorneys' fees of
the Lenders in connection with the enforcement of the this Agreement and the
Notes, whether in any action, suit or litigation, any bankruptcy, insolvency or
other similar proceeding affecting creditors' rights generally or otherwise.

      (b) The Borrower agrees not to assert any claim against any Lender or any
of its affiliates, or any of its directors, officers, employees, attorneys or
agents, on any theory of liability, for special, indirect, consequential, or
punitive damages arising out of or otherwise relating to any of the transactions
contemplated herein or in the Notes.

      (c) If the Borrower fails to pay when due any costs, expenses or other
amounts payable by it under this Agreement, such amount may be paid on behalf of
the Borrower by the Lenders in their sole discretion.

      (d) The Borrower's obligations under this Section 4.1 shall survive any
termination of this Agreement and the payment in full of the obligations
hereunder, and are in addition to and not in substitution of any of its
obligations in this Agreement or the Notes.

      4.2 Right of Setoff. Upon the occurrence and during the continuance of any
Event of Default each Lender and each of its Affiliates is hereby authorized at
any time and from time to time, to the fullest extent permitted by law, to set
off and otherwise apply any and all amounts such Lender may owe to Borrower
pursuant to any agreement or otherwise to and in reduction of the obligations
hereunder, irrespective of whether such Lender shall have made any demand under
this Agreement or the Notes and although such obligations may be unmatured. Each
Lender agrees promptly to notify the Borrower after any such setoff and
application; provided, however, that the failure to give such notice shall not
affect the validity of such setoff and application. The rights of the Lenders
and their Affiliates under this Section 4.2 are in addition to other rights and
remedies (including, without limitation, other rights of setoff) that the
Lenders and their Affiliates may have.

SECTION 5.  TERM.

      The term of this Agreement commences on the Closing Date and shall extend
through the date upon which all the Borrower's obligations hereunder and under
the Notes have been fulfilled.


                                      -3-
<PAGE>

SECTION 6. EVENTS OF DEFAULT

      6.1 If any of the following events ("Events of Default") shall occur and
be continuing:

      (a) the Borrower shall fail to pay any principal of, or interest on, the
Loan, or the Borrower shall fail to make any other payment under this Agreement
or the Notes, in each case when the same becomes due and payable and such
failure continues unremedied for fifteen days after such amount was due and
payable;

      (b) the Borrower shall admit in writing its inability to pay its debts
generally, or shall make a general assignment for the benefit of creditors; or
any proceeding shall be instituted by or against the Borrower seeking to
adjudicate it a bankrupt or insolvent, or seeking liquidation, winding up,
reorganization, arrangement, adjustment, protection, relief, or composition of
it or its debts under any law relating to bankruptcy, insolvency or
reorganization or relief of debtors, or seeking the entry of an order for relief
or the appointment of a receiver, trustee, or other similar official for it or
for any substantial part of its property and, in the case of any such proceeding
instituted against it (but not instituted by it) that is being diligently
contested by it in good faith, either such proceeding shall remain undismissed
or unstayed for a period of 60 days or any of the actions sought in such
proceeding (including, without limitation, the entry of an order for relief
against, or the appointment of a receiver, trustee, custodian or other similar
official for, it or any substantial part of its property) shall occur; or the
Borrower shall take any corporate action to authorize any of the actions set
forth above in this Section 6.1; or

      (c) any provision of this Agreement or the Notes shall for any reason
cease to be valid and binding on or enforceable against the Borrower in any
material respect, or the Borrower shall so state in writing;

then, and in any such event, the Lenders may, by notice to the Borrower, declare
the Loan, all interest thereon and all other amounts payable under this
Agreement and the Notes to be forthwith due and payable, whereupon the Loan, all
such interest and all such amounts shall become and be forthwith due and
payable, without presentment, demand, protest or further notice of any kind;
provided, however, that in the event of an actual or deemed entry of an order
for relief with respect to the Borrower under the Federal Bankruptcy Code, the
Loan, all such interest and all such amounts shall automatically become and be
due and payable, without presentment, demand, protest or any notice of any kind.

      Each Lender shall also have all of its rights and remedies under
applicable law.

SECTION 7. DEFINITIONS.

      7.1 Defined Terms. The following terms shall have the definitions set
forth below.


                                      -4-
<PAGE>

      "Affiliate" means, with respect to any Person, any other Person that,
directly or indirectly controls, is controlled by or is under common control
with such Person or is a director or officer of such Person. For purposes of
this definition, the term "control" (including the terms "controlling",
"controlled by" and "under common control with") of a Person means the
possession, direct or indirect, of the power to vote 5% or more of the voting
stock of such Person or to direct or cause the direction of the management and
policies of such Person, whether through the ownership of voting stock, by
contract or otherwise.

      "Closing" means the funding of the Loan by the Lenders pursuant to this
Agreement.

      "Closing Date" means the date upon which the Lenders fund the Loan
pursuant to this Agreement.

      "Default" means any Event of Default or any event that would constitute an
Event of Default but for the requirement that notice be given or time elapse or
both.

      "Event of Default" has the meaning specified in Section 6.

      "Notes" shall mean the Promissory Notes, dated of even date herewith,
in the original aggregate principal amount of_____________ dollars
(US$________), of the Borrower and payable to the Lenders, evidencing amounts
outstanding under the Loan, as the same may be amended, extended, renewed,
restated or replaced from time to time.

      "Person" means an individual, partnership, corporation (including a
business trust), limited liability company, joint stock company, trust,
unincorporated association, joint venture or other entity, or a government or
any political subdivision or agency thereof.

SECTION 8. MISCELLANEOUS.

      8.1 Certain Waivers. All obligations hereunder shall be payable by
Borrower as provided for herein and, in full, at the termination of this
Agreement; Borrower waives presentment and protest of any instrument and notice
thereof, notice of default and, to the extent permitted by applicable law, all
other notices to which Borrower might otherwise be entitled.

      8.2 No Waiver by the Lenders. The Lenders' failure to exercise any right,
remedy or option under this Agreement or any supplement or other agreement
between the Lenders and Borrower or delay by the Lenders in exercising the same
will not operate as a waiver. No waiver by the Lenders will be effective unless
in writing and then only to the extent stated. No waiver by the Lenders shall
affect their right to require strict


                                      -5-
<PAGE>

performance of this Agreement. The Lenders' rights and remedies will be
cumulative and not exclusive.

      8.3 Binding on Successor and Assigns. All terms, conditions, promises,
covenants, provisions and warranties shall inure to the benefit of and bind the
Lenders' and Borrower's respective representatives, successors and assigns.

      8.4 Severability. If any provision of this Agreement shall be prohibited
or invalid under applicable law, it shall be ineffective only to such extent,
without invalidating the remainder of this Agreement.

      8.5 Amendments; Assignments. This Agreement may not be modified, altered
or amended, except by an agreement in writing signed by Borrower and the
Lenders. Borrower may not sell, assign or transfer any interest in this
Agreement or any other Loan Document, or any portion thereof, including, without
limitation, any of Borrower's rights, title, interests, remedies, powers and
duties hereunder or thereunder.

      8.6 Integration. This Agreement, together with the Notes, reflect the
entire understanding of the parties with respect to the transactions
contemplated hereby.

      8.7 Governing Law; Jurisdiction and Venue. This Agreement and the legal
relations between the parties hereto shall be governed by and construed in
accordance with the laws of the State of Massachusetts applicable to contracts
made and to be performed entirely within such State.

      8.8 Survival. All of the representations and warranties of Borrower
contained in this Agreement shall survive the execution, delivery and acceptance
thereof by the parties. No termination of this Agreement or of any guaranty of
the obligations hereunder shall affect or impair the powers, obligations,
duties, rights, representations, warranties or liabilities of the parties hereto
and all shall survive such termination.

      8.9 Notices. Any notice required hereunder shall be in writing and
addressed to the Borrower and the Lenders at their addresses set forth at the
beginning of this Agreement. Notices hereunder shall be deemed received on the
earlier of receipt, whether by mail, personal delivery, facsimile, overnight
courier or otherwise, or three (3) days after deposit in the United States mail,
postage prepaid.

      8.10 Captions. The Section titles contained in this Agreement are for
convenience of reference only and shall not affect the interpretation of this
Agreement.

      8.11 Injunctive Relief. Borrower recognizes that, in the event Borrower
fails to perform, observe or discharge any of its obligations under this
Agreement, any remedy of law may prove to be inadequate relief to the Lenders.
Therefore, the Lenders, if they so request, shall be entitled to temporary and
permanent injunctive relief in any such case without the necessity of proving
actual damages.


                                      -6-
<PAGE>

      8.12 Counterparts; Telecopy Execution. This Agreement may be executed in
any number of separate counterparts, each of which, when taken together, shall
constitute one and the same agreement, admissible into evidence, notwithstanding
the fact that all parties have not signed the same counterpart. Delivery of an
executed counterpart of this Agreement by telefacsimile shall be equally as
effective as delivery of a manually executed counterpart of this Agreement. Any
party delivering an executed counterpart of this Agreement by telefacsimile
shall also deliver a manually executed counterpart of this Agreement, but the
failure to deliver a manually executed counterpart shall not affect the
validity, enforceability, and binding affect of this Agreement.

      8.13 Construction. The parties acknowledge that each party and its counsel
have reviewed and participated in the preparation of this Agreement and that the
normal rule of construction to the effect that any ambiguities are to be
resolved against the drafting party shall not be employed in the interpretation
of this Agreement or any amendments or exhibits hereto.

      8.14 Time of Essence. Time is of the essence for the performance by
Borrower of the obligations set forth in this Agreement.

      8.15 MUTUAL WAIVER OF RIGHT TO JURY TRIAL. THE LENDERS AND BORROWER EACH
HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING BASED UPON,
ARISING OUT OF, OR IN ANY WAY RELATING TO: (i) THIS AGREEMENT; OR (ii) ANY OTHER
PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN THE LENDERS AND BORROWER; OR
(iii) ANY CONDUCT, ACTS OR OMISSIONS OF THE LENDERS OR BORROWER OR ANY OF THEIR
DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR ANY OTHER PERSONS
AFFILIATED WITH THE LENDERS OR BORROWER; IN EACH OF THE FOREGOING CASES, WHETHER
SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

      8.16 AGENT. In the event more than one Person is named as Lender
hereunder, each such Person, as a Lender hereunder, hereby appoints Amer Tabbah
as its agent ("Agent") with full authority to take any action and to execute any
instrument in the place and stead of such Lender to the same extent as the
Lender may do or take hereunder, and any notices or other communications
required to be given by the Borrower to the Lender shall be satisfied by the
provision of same to the Agent.

      IN WITNESS WHEREOF, the parties hereto have caused the Agreement to be
duly executed as of the day and year first above written.

                                       HYBRIDON, INC.

                                       By:
                                          --------------------------------------
                                       Name:  Robert G. Andersen
                                       Title: Vice President, Operations and
                                              Planning

[New Lenders]

By:
   --------------------------------
   Amer Tabbah, Attorney-in-Fact


                                      -7-
<PAGE>

                                    EXHIBIT A

                                 HYBRIDON, INC.

                              CONVERSION PROVISION

      Lenders will have the option to invest in two different financing vehicles
as described below.

A.    PREFERRED STOCK (MAXIMUM TEN MILLION DOLLARS [US$10MM])

      o     Rank senior to existing preferred stock, but junior to all debt.

      o     Dividend rate will be eight per cent (8%), payable semi-annually in
            arrears.

      o     Dividend is payable in Hybridon common stock, priced at market on
            the record date.

      o     Convertible to common at fifty cents (US$0.50) per share at any
            time.

      o     Callable by Hybridon at any time after three (3) years.


B.    SECURED DEBT (MAXIMUM FIVE MILLION DOLLARS [US$5MM])

      o     Five (5) year term.

      o     Interest rate of eight per cent (8%), payable semi-annually in
            arrears.

      o     Interest is payable in cash or Hybridon common stock, at the
            Company's option. If paid in stock, the stock will be priced at
            market on the interest due date.

      o     Convertible into common stock at sixty cents (US$0.60) per share.

      o     Prepayable by Hybridon, in whole or in part, at any time in cash.

      o     If prepaid at Hybridon's election during the first three years of
            the term, Hybridon will issue a number of warrants to purchase
            common stock equal to the number of shares into which the amount
            prepaid was convertible, with a sixty cent (US$0.60) strike price.

      o     Secured by all assets.

      o     Ranks pari passu with the current six million dollars (US$6MM) loan.


                                      -8-


THE TERMS OF THIS PROMISSORY NOTE ARE SUBJECT TO THE TERMS OF A SUBSCRIPTION
AGREEMENT AND A LOAN AGREEMENT, COPIES OF WHICH ARE AVAILABLE FROM HYBRIDON,
INC. THE SECURITIES REPRESENTED BY THIS PROMISSORY NOTE HAVE NOT BEEN REGISTERED
UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), OR ANY APPLICABLE STATE SECURITIES LAWS, AND MAY NOT BE SOLD, OFFERED FOR
SALE, PLEDGED OR HYPOTHECATED OR OTHERWISE TRANSFERRED IN THE ABSENSE OF A
REGISTRATION STATEMENT IN EFFECT WITH RESPECT TO THE SECURITIES UNDER THE
SECURITIES ACT OR AN EXEMPTION FROM THE SECURITIES ACT. ANY SUCH TRANSFER MAY
ALSO BE SUBJECT TO COMPLIANCE WITH APPLICABLE STATE SECURITIES LAWS AND THE LAWS
OF OTHER APPLICABLE JURISDICTIONS.


                                 PROMISSORY NOTE


US$__________________                                         October ____, 1999
                                                          Milford, Massachusetts


         FOR VALUE RECEIVED, the undersigned, Hybridon, Inc., a Delaware
corporation (the "Maker"), hereby promises to pay to ___________________ (the
"Payee"), or his assigns, the principal sum of __________________ Dollars
(US$__________), together with interest thereon from the date hereof on the
unpaid principal balance hereunder at the rate (the "Rate of Interest")
(calculated on the basis of a 360-day year of twelve 30-day months) of eight
percent (8%) per annum, payable in common stock of the Payee at the rate of
fifty cents (US$0.50) per share. Interest on this Note shall be due and payable
monthly in arrears on the first business day of each month commencing on
November 1, 1999. Notwithstanding the foregoing, this Note may be revised or
extended as provided in the Loan Agreement of even date herewith between the
Maker and the Payee ("Loan Agreement"). All amounts due hereunder shall be
subject to conversion into preferred stock of the Maker or secured debt, at the
option of the Payee, as provided in the Loan Agreement. All cash payments under
this Note shall be made in lawful money of the United States in immediately
available funds. Any common stock of the Maker issued under this Note shall bear
an appropriate securities law legend and, at the request of the Maker, the
issuance thereof shall be subject to the Payee's execution and delivery of an
appropriate private placement agreement.

         Maker may repay all or any portion of the principal amount outstanding
hereunder without premium or penalty at any time. All repayments of the
principal amount


                                      -1-
<PAGE>

outstanding  hereunder or any portion  thereof  shall be made  together with the
payment of all interest  accrued on the amount  repaid  through the date of such
repayment.

         If any of the following events ("Events of Default") shall occur and be
continuing:

(a)   the Maker shall admit in writing its inability to pay its debts generally,
      or shall make a general assignment for the benefit of creditors; or any
      proceeding shall be instituted by or against the Maker seeking to
      adjudicate it a bankrupt or insolvent, or seeking liquidation, winding up,
      reorganization, arrangement, adjustment, protection, relief, or
      composition of it or its debts under any law relating to bankruptcy,
      insolvency or reorganization or relief of debtors, or seeking the entry of
      an order for relief or the appointment of a receiver, trustee, or other
      similar official for it or for any substantial part of its property and,
      in the case of any such proceeding instituted against it (but not
      instituted by it) that is being diligently contested by it in good faith,
      either such proceeding shall remain undismissed or unstayed for a period
      of 60 days or any of the actions sought in such proceeding (including,
      without limitation, the entry of an order for relief against, or the
      appointment of a receiver, trustee, custodian or other similar official
      for, it or any substantial part of its property) shall occur; or the Maker
      shall take any corporate action to authorize any of the actions set forth
      above; or

(b)   the Maker shall fail to pay any principal or interest hereunder, in each
      case when the same becomes due and payable, and such failure continues
      unremedied for fifteen days after such amount was due and payable; or

(c)   an "Event of Default" as defined in the Loan Agreement shall occur and be
      continuing,

then, all unpaid principal of and interest on this Note shall become immediately
due and payable, without presentment, demand, protest or further notice of any
kind, and the Payee may proceed to protect and enforce its rights hereunder by
an action at law, suit in equity or other appropriate proceeding, in the Payee's
sole discretion.

      In the event of any failure to make a full and timely payment of any
amount due under this Note, or if any other event rendering the entire unpaid
principal amount of this Note immediately due and payable shall occur, the Maker
will pay to the Payee reasonable attorneys' fees incurred by Payee in connection
with any action relating to collection of this Note.


                                      -2-
<PAGE>

      No course of dealing and no delay or failure on the part of the Payee in
exercising any right, power or remedy hereunder shall operate as a waiver
thereof or otherwise prejudice any of the Payee's rights, powers and remedies,
and no single or partial exercise of a right, power or remedy shall preclude a
further exercise thereof or the exercise of another right, power or remedy. The
Maker hereby waives presentment for payment, demand, protest, notice of dishonor
and nonpayment, and all other notices and demands in connection with the
delivery, acceptance, performance, default, endorsement or guarantee of this
Note. The Maker shall not have any right to offset any payments due to the Payee
hereunder against any amounts claimed to be owed to Payee hereunder or
otherwise, but shall be required to continue to make all payments to the Payee
when due hereunder.

      This Note shall be governed by and construed in accordance with the
internal laws of the Commonwealth of Massachusetts without giving effect to the
conflict of laws principles thereof. Any provisions hereof which may prove
unenforceable under any law shall not affect the validity of any other
provisions hereof.

      The Maker hereby irrevocably waives all right to trial by jury in any
action, proceeding or counterclaim (whether based on contract, tort or
otherwise) arising out of or relating to this Note or the negotiation,
administration, performance or enforcement hereof.

      This Note may not be altered or amended except by a writing duly signed by
the party against whom such alteration or amendment is sought to be enforced.
All of the terms and provisions of this Note shall be applicable to and binding
upon each and every maker, holder, endorser, surety, guarantor and all other
persons who are or may become liable for the payment hereof and their respective
successors or assigns.

      IN WITNESS WHEREOF, the undersigned has duly caused this Note to be
executed and delivered as of the date and year first above written.

                                        HYBRIDON, INC.



                                        By:
                                               ---------------------------------
                                        Name:  Robert G. Andersen
                                        Title: Vice President, Operations and
                                               Planning


                                      -3-




            LOAN AGREEMENT ("Agreement") dated as of September 1, 1999, is
entered into by and among HYBRIDON, INC. (the "Borrower"), a Delaware
corporation having its principal place of business at 155 Fortune Boulevard,
Milford, Massachusetts 01757 and E. Andrews Grinstead III, residing at 33
Edgehill Road, Brookline, Massachusetts 02445, (the "Lenders").

                              W I T N E S S E T H:

            WHEREAS, the Borrower has requested and the Lenders have agreed to
make a loan to the Borrower in an aggregate principal amount of Five Hundred
Thousand Dollars and 00/100 ($500,000), the ("Loan") on the terms, and subject
to the conditions set forth herein;

            NOW, THEREFORE, IT IS AGREED that, in consideration of the premises
and mutual agreements contained herein, the parties hereby agree as follows:

SECTION 1. THE LOAN.

            1.1 Loan. Subject to and upon the terms and conditions set forth
herein, Lenders agree to make the Loan to Borrower on September 1, 1999 in an
aggregate principal amount of Five Hundred Thousand Dollars and 00/100
($500,000) (the "Loan"). At the Borrower's request, the Lenders may, but are not
required to, make additional advances (up to a maximum of an additional
$500,000) to the Borrower under this Agreement. Any such additional advances
shall also be deemed to be part of the Loan hereunder.

            1.2 Senior Indebtedness. The Lender and the Borrower agree that the
Loan constitutes "Senior Indebtedness" under the Borrower's 9% Convertible
Secured Notes due 2004.

            1.3 Letter of Intent. It is the intent of the parties that, upon the
closing of any third party debt financing which closes on or before March 1,
2000, including the Letter of Intent Transaction, the Loan will be converted
into a portion of the credit facility made pursuant to such debt financing. If
for any reason, however, a third party debt financing does not close on or
before March 1, 2000, the Lenders shall have the option (a) to convert the
entire Loan to a five-year term loan (maturing on August 31, 2004) substantially
on the terms set forth in the Letter of Intent, in which event the Borrower
shall issue to the Lenders the warrants which the Lenders would have otherwise
received if the Loan had been made as part of the Letter of Intent Transaction,
(b) to convert the entire Loan to a demand loan bearing interest at the rates
provided in Section 2 below or (c) to declare the entire principal balance,
together with accrued but unpaid interest thereon, immediately due and payable.

<PAGE>

SECTION 2. INTEREST RATE AND OTHER CHARGES.

            2.1 Interest. (a) Borrower shall pay the Lenders interest monthly,
in arrears, on the unpaid principal amount of the Loan until the Loan has been
paid in full at the following rate: at the option of the Lender, either (a) 12%
per annum, payable in cash or (b) 15% per annum, payable in common stock of the
Borrower at the rate of fifty cents ($0.50) per share. Any common stock of the
Borrower issued pursuant to this Section 2.1 shall bear an appropriate
securities law legend and the issuance thereof shall be subject to the Lender's
execution and delivery of an appropriate private placement agreement.

            (b) Interest shall accrue from and including the Closing Date to but
excluding the date of any repayment and shall be payable, in cash or in common
stock, as provided above, on the first business day of each month that the Loan
is outstanding, commencing October 1, 1999 and upon any prepayment (to the
extent accrued on the amount being prepaid), and at maturity.

            (c) All computations of interest hereunder shall be made on the
basis of a 360-day year consisting of 12 30-day months.

            2.2 Excess Interest. In no event whatsoever shall the interest rate
and other charges charged hereunder exceed the highest rate permissible under
any law which a court of competent jurisdiction shall, in a final determination,
deem applicable hereto. In the event that a court determines that the Lenders
have received interest or other charges hereunder in excess of the highest
permissible rate applicable thereto, the Lenders shall promptly apply such
excess to the Obligations in such order as the Lenders shall determine in their
discretion or refund the amount thereof to Borrower, and the provisions hereof
shall be deemed amended to provide for such permissible rate.

SECTION 3. PRINCIPAL PAYMENTS AND PREPAYMENTS.

            3.1 Repayment. Except as provided in Section 1.3 above, Borrower
shall pay to the Lenders the principal amount of the Loan, less any principal
prepayments made pursuant to the terms of this Agreement, on or before March 1,
2000.

            3.2 Prepayments. Borrower may prepay the Loan in whole or in part
without premium or penalty at any time. Prepayments of the Loan may not be
re-borrowed. All prepayments of the Loan or any portion thereof shall be made
together with the payment of all interest accrued on the amount repaid through
the date of such prepayment.

            3.3 Notices. Borrower shall give the Lenders ten days' prior written
notice of each prepayment of the Loan. Each notice of prepayment shall specify
the amount of the Loan to be prepaid and the date of prepayment.

            3.4 Payments Without Deductions. Borrower shall pay principal,
interest, and all other amounts payable hereunder, or under any Loan Document,
without any deduction whatsoever, including, but not limited to, any deduction
for any setoff or counterclaims


                                      -2-
<PAGE>

whatsoever, provided that with respect to withholding taxes Borrower may make
such deductions as may be required by law if Lender fails to deliver a Form W-9
to Borrower.

SECTION 4.  COSTS AND EXPENSES, INDEMNITY AND SETOFF

            4.1 (a) The Borrower agrees to pay on demand all costs and expenses
of the Lenders in connection with the enforcement of the Loan Documents, whether
in any action, suit or litigation, any bankruptcy, insolvency or other similar
proceeding affecting creditors' rights generally or otherwise (including,
without limitation, the fees and expenses of counsel for the Lenders with
respect thereto).

            (b) The Borrower agrees to indemnify and hold harmless the Lenders
and each of their respective Affiliates, officers, directors, employees, agents
and advisors (each, an "Indemnified Party") from and against any and all claims
that may be asserted against, and any and all damages, claims, losses,
liabilities, deficiencies, judgments, costs and expenses of any kind (including,
without limitation, amounts paid in settlement, court costs, reasonable fees and
expenses of counsel and other professionals) (collectively, "Indemnified
Liabilities") that may be incurred by or awarded against, any Indemnified Party,
in each case arising out of or in connection with or by reason of, or in
connection with the preparation for a defense of, any investigation, litigation
or proceeding arising out of, related to or in connection with this Agreement or
any other Loan Document, or the exercise of any right or remedy hereunder, in
each case whether or not such investigation, litigation or proceeding is brought
by the Borrower, its directors, shareholders or creditors or an Indemnified
Party or any Indemnified Party is otherwise a party thereto and whether or not
the transactions contemplated hereby are consummated, except to the extent such
claim, damage, loss, liability or expense is found in a final, nonappealable
judgment by a court of competent jurisdiction to have resulted from such
Indemnified Party's gross negligence or willful misconduct. To the extent that
the undertaking to indemnify, pay and hold harmless set forth in the preceding
sentence may be unenforceable because it is violative of any law of public
policy, the Borrower will contribute the maximum portion that it is permitted to
pay and satisfy under applicable law to the payment and satisfaction of all
Indemnified Liabilities incurred by the Indemnified Parties or any of them. The
Borrower also agrees not to assert any claim against any Lender or any of its
affiliates, or any of its directors, officers, employees, attorneys or agents,
on any theory of liability, for special, indirect, consequential, punitive or
other damages arising out of or otherwise relating to any of the transactions
contemplated herein or in any other Loan Document.

            (c) If the Borrower fails to pay when due any costs, expenses or
other amounts payable by it under any Loan Document, including, without
limitation, fees and expenses of counsel and indemnities, such amount may be
paid on behalf of the Borrower by the Lenders in their sole discretion.

            (d) The Borrower's obligations under this Section 4.1 shall survive
any termination of this Agreement and the payment in full of the Obligations,
and are in addition to and not in substitution of any of its obligations in this
Agreement or the other Loan Documents.


                                      -3-
<PAGE>

            4.2 Right of Setoff. Upon the occurrence and during the continuance
of any Event of Default each Lender and each of its Affiliates is hereby
authorized at any time and from time to time, to the fullest extent permitted by
law, to set off and otherwise apply any and all amounts any Lender may owe to
Borrower pursuant to any agreement or otherwise to and in reduction of the
Obligations hereunder, irrespective of whether such Lender shall have made any
demand under this Agreement or such Note and although such obligations may be
unmatured. Each Lender agrees promptly to notify the Borrower after any such
setoff and application; provided, however, that the failure to give such notice
shall not affect the validity of such setoff and application. The rights of each
Lender and its Affiliates under this Section 4.2 are in addition to other rights
and remedies (including, without limitation, other rights of setoff) that such
Lender and its Affiliates may have.

SECTION 5. TERM.

            The term of this Agreement commences on the Closing Date and shall
extend through the date upon which all Obligations have been fulfilled.

SECTION 6. EVENTS OF DEFAULT

            6.1 If any of the following events ("Events of Default") shall occur
and be continuing:

            (a) the Borrower shall fail to pay any principal of, or interest on,
the Loan, or the Borrower shall fail to make any other payment under any Loan
Document, in each case when the same becomes due and payable and such failure
continues unremedied for fifteen days after such amount was due and payable;

            (b) the Borrower shall generally not pay its debts as such debts
become due, or shall admit in writing its inability to pay its debts generally,
or shall make a general assignment for the benefit of creditors; or any
proceeding shall be instituted by or against the Borrower seeking to adjudicate
it a bankrupt or insolvent, or seeking liquidation, winding up, reorganization,
arrangement, adjustment, protection, relief, or composition of it or its debts
under any law relating to bankruptcy, insolvency or reorganization or relief of
debtors, or seeking the entry of an order for relief or the appointment of a
receiver, trustee, or other similar official for it or for any substantial part
of its property and, in the case of any such proceeding instituted against it
(but not instituted by it) that is being diligently contested by it in good
faith, either such proceeding shall remain undismissed or unstayed for a period
of 60 days or any of the actions sought in such proceeding (including, without
limitation, the entry of an order for relief against, or the appointment of a
receiver, trustee, custodian or other similar official for, it or any
substantial part of its property) shall occur; or the Borrower shall take any
corporate action to authorize any of the actions set forth above in this Section
6.1; or

            (c) any provision of any Loan Document shall for any reason cease to
be valid and binding on or enforceable against the Borrower in any material
respect, or the Borrower shall so state in writing;


                                      -4-
<PAGE>

then, and in any such event, the Lenders may, by notice to the Borrower, declare
the Loan, all interest thereon and all other amounts payable under this
Agreement and the other Loan Documents to be forthwith due and payable,
whereupon the Loan, all such interest and all such amounts shall become and be
forthwith due and payable, without presentment, demand, protest or further
notice of any kind, all of which are hereby expressly waived by the Borrower;
provided, however, that in the event of an actual or deemed entry of an order
for relief with respect to the Borrower under the Federal Bankruptcy Code, the
Loan, all such interest and all such amounts shall automatically become and be
due and payable, without presentment, demand, protest or any notice of any kind,
all of which are hereby expressly waived by the Borrower.

            Each Lender shall also have all of its rights and remedies under
applicable law.

SECTION 7. DEFINITIONS.

            7.1 Defined Terms. The following terms shall have the definitions
set forth below.

            "Affiliate" means, with respect to any Person, any other Person
that, directly or indirectly controls, is controlled by or is under common
control with such Person or is a director or officer of such Person. For
purposes of this definition, the term "control" (including the terms
"controlling", "controlled by" and "under common control with") of a Person
means the possession, direct or indirect, of the power to vote 5% or more of the
voting stock of such Person or to direct or cause the direction of the
management and policies of such Person, whether through the ownership of voting
stock, by contract or otherwise.

            "Closing" means the funding of the Loan by the Lenders pursuant to
this Agreement.

            "Closing Date" means the date of the Closing.

            "Default" means any Event of Default or any event that would
constitute an Event of Default but for the requirement that notice be given or
time elapse or both.

            "Event of Default" has the meaning specified in Section 6.

            "Letter of Intent Transaction" means the transaction described in
the draft Letter of Intent (the "Letter of Intent"), a copy of which is attached
hereto as Exhibit A.

            "Loan Documents" means, collectively, this Agreement, the Note, the
Security Agreement, any other note or notes executed by Borrower and payable to
Lender, and any other agreement entered into in connection with this Agreement,
together with all amendments, changes, extensions, modifications, refinancings,
refundings, renewals, replacements, restatements, or supplements, of or to any
of the foregoing.


                                      -5-
<PAGE>

            "Note" shall mean that certain Promissory Note, dated of even date
herewith, in the original aggregate principal amount of $500,000, of the
Borrower and payable to the Lender, evidencing amounts outstanding under the
Loan, as the same may be amended, extended, renewed, restated or replaced from
time to time.

            "Obligations" means all present and future loans, advances, debts,
liabilities, obligations, covenants, duties and indebtedness at any time owing
by Borrower to the Lenders, whether evidenced by this Agreement, any note or
other instrument or document, whether arising from an extension of credit,
opening of a letter of credit, banker's acceptance, loan, guaranty,
indemnification or otherwise, whether direct or indirect (including, without
limitation, those acquired by assignment and any participation by the Lenders in
Borrower's debts owing to others), absolute or contingent, due or to become due,
and all interest, charges, expenses, fees, attorneys, fees and any other sums
chargeable to Borrower hereunder or under any other agreement with Lender.

            "Person" means an individual, partnership, corporation (including a
business trust), limited liability company, joint stock company, trust,
unincorporated association, joint venture or other entity, or a government or
any political subdivision or agency thereof.

            "Security Agreement" means the Security Agreement of even date
herewith between the Borrower and the Lenders.

SECTION 8. MISCELLANEOUS.

            8.1 Certain Waivers. All Obligations shall be payable by Borrower as
provided for herein and, in full, at the termination of this Agreement; Borrower
waives presentment and protest of any instrument and notice thereof, notice of
default and, to the extent permitted by applicable law, all other notices to
which Borrower might otherwise be entitled.

            8.2 No Waiver by the Lenders. The Lenders failure to exercise any
right, remedy or option under this Agreement or any supplement or other
agreement between the Lenders and Borrower or delay by the Lenders in exercising
the same will not operate as a waiver. No waiver by the Lenders will be
effective unless in writing and then only to the extent stated. No waiver by the
Lenders shall affect it right to require strict performance of this Agreement.
The Lenders' rights and remedies will be cumulative and not exclusive.

            8.3 Binding on Successor and Assigns. All terms, conditions,
promises, covenants, provisions and warranties shall inure to the benefit of and
bind the Lenders and Borrower's respective representatives, successors and
assigns.

            8.4 Severability. If any provision of this Agreement shall be
prohibited or invalid under applicable law, it shall be ineffective only to such
extent, without invalidating the remainder of this Agreement.


                                      -6-
<PAGE>

            8.5 Amendments; Assignments. This Agreement may not be modified,
altered or amended, except by an agreement in writing signed by Borrower and the
Lenders. Borrower may not sell, assign or transfer any interest in this
Agreement or any other Loan Document, or any portion thereof, including, without
limitation, any of Borrower's rights, title, interests, remedies, powers and
duties hereunder or thereunder.

            8.6 Integration. This Agreement, together with the other Loan
Documents, reflect the entire understanding of the parties with respect to the
transactions contemplated hereby.

            8.7 Governing Law; Jurisdiction and Venue. This Agreement and the
legal relations between the parties hereto shall be governed by and construed in
accordance with the laws of the State of Massachusetts applicable to contracts
made and to be performed entirely within such State.

            8.8 Survival. All of the representations and warranties of Borrower
contained in this Agreement shall survive the execution, delivery and acceptance
thereof by the parties. No termination of this Agreement or of any guaranty of
the Obligations shall affect or impair the powers, obligations, duties, rights,
representations, warranties or liabilities of the parties hereto and all shall
survive such termination.

            8.9 Notices. Any notice required hereunder shall be in writing and
addressed to the Borrower and the Lenders at their addresses set forth at the
beginning of this Agreement. Notices hereunder shall be deemed received on the
earlier of receipt, whether by mail, personal delivery, facsimile, overnight
courier or otherwise, or three (3) days after deposit in the United States mail,
postage prepaid.

            8.10 Captions. The Section titles contained in this Agreement are
for convenience of reference only and shall not affect the interpretation of
this Agreement.

            8.11 Injunctive Relief. Borrower recognizes that, in the event
Borrower fails to perform, observe or discharge any of its Obligations under
this Agreement, any remedy of law may prove to be inadequate relief to the
Lenders. Therefore, the Lenders, if they so request, shall be entitled to
temporary and permanent injunctive relief in any such case without the necessity
of proving actual damages.

            8.12 Counterparts; Telecopy Execution. This Agreement may be
executed in any number of separate counterparts, each of which, when taken
together, shall constitute one and the same agreement, admissible into evidence,
notwithstanding the fact that all parties have not signed the same counterpart.
Delivery of an executed counterpart of this Agreement by telefacsimile shall be
equally as effective as delivery of a manually executed counterpart of this
Agreement. Any party delivering an executed counterpart of this Agreement by
telefacsimile shall also deliver a manually executed counterpart of this
Agreement, but the failure to deliver a manually executed counterpart shall not
affect the validity, enforceability, and binding affect of this Agreement.


                                      -7-
<PAGE>

            8.13 Construction. The parties acknowledge that each party and its
counsel have reviewed and participated in the preparation of this Agreement and
that the normal rule of construction to the effect that any ambiguities are to
be resolved against the drafting party shall not be employed in the
interpretation of this Agreement or any amendments or exhibits hereto.

            8.14 Time of Essence. Time is of the essence for the performance by
Borrower of the Obligations set forth in this Agreement.

            8.15 MUTUAL WAIVER OF RIGHT TO JURY TRIAL. THE LENDERS AND BORROWER
EACH HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING BASED
UPON, ARISING OUT OF, OR IN ANY WAY RELATING TO: (i) THIS AGREEMENT; OR (ii) ANY
OTHER PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN THE LENDERS AND
BORROWER; OR (iii) ANY CONDUCT, ACTS OR OMISSIONS OF THE LENDERS OR BORROWER OR
ANY OF THEIR DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR ANY OTHER
PERSONS AFFILIATED WITH THE LENDERS OR BORROWER; IN EACH OF THE FOREGOING CASES,
WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

            IN WITNESS WHEREOF, the parties hereto have caused the Agreement to
be duly executed as of the day and year first above written.

                                          HYBRIDON, INC.



                                          By:
                                                   -----------------------------
                                          Name     Robert G. Andersen
                                          Title:   Vice President, Operations
                                                   and Planning




                                          ------------------------------------
                                                   E. Andrews Grinstead III

                                      -8-


                              TERM PROMISSORY NOTE


$500,000                                                       September 1, 1999
                                                          Milford, Massachusetts

      FOR VALUE RECEIVED, the undersigned, Hybridon, Inc., a Delaware
corporation (the "Maker"), hereby promises to pay to E. Andrews Grinstead III
(the "Payee"), or his assigns, the principal sum of Five Hundred Thousand
Dollars ($500,000), together with interest thereon from the date hereof at the
following rate (the "Rate of Interest") (calculated on the basis of a 360-day
year of twelve 30-day months) on the unpaid principal balance hereunder: at the
option of the Lender, either (a) 12% per annum, payable in cash or (b) 15% per
annum, payable in common stock of the Payee at the rate of fifty cents ($0.50)
per share. Interest on this Note shall be due and payable monthly in arrears on
the first business day of each month commencing on October 1, 1999 until March
1, 2000. Notwithstanding the foregoing, this Note may be revised or extended as
provided in the Loan Agreement of even date herewith between the Maker and the
Payee ("Loan Agreement"). All cash payments under this Note shall be made in
lawful money of the United States in immediately available funds. Any common
stock of the Maker issued under this Note shall bear an appropriate securities
law legend and the issuance thereof shall be subject to the Payee's execution
and delivery of an appropriate private placement agreement.

      Maker may prepay all or any portion of the principal amount outstanding
hereunder without premium or penalty at any time. All prepayments of the
principal amount outstanding hereunder or any portion thereof shall be made
together with the payment of all interest accrued on the amount repaid through
the date of such prepayment.

      If any of the following events ("Events of Default") shall occur and be
continuing:

(a)   the Maker shall generally not pay its debts as such debts become due, or
      shall admit in writing its inability to pay its debts generally, or shall
      make a general assignment for the benefit of creditors; or any proceeding
      shall be instituted by or against the Maker seeking to adjudicate it a
      bankrupt or insolvent, or seeking liquidation, winding up, reorganization,
      arrangement, adjustment, protection, relief, or composition of it or its
      debts under any law relating to bankruptcy, insolvency or reorganization
      or relief of debtors, or seeking the entry of an order for relief or the
      appointment of a receiver, trustee, or other similar official for it or
      for any substantial part of its property and, in the case of any such
      proceeding instituted against it (but not instituted by it) that is being
      diligently contested by it in good faith, either such proceeding shall
      remain undismissed or unstayed for a period of 60 days or any of the
      actions sought in such proceeding (including, without limitation, the
      entry of an order for relief against, or the appointment of a receiver,
      trustee, custodian or other similar official for, it or any substantial
      part of its property) shall occur; or the Maker shall take any corporate
      action to authorize any of the actions set forth above; or


                                      -1-
<PAGE>

(b)   any event or condition shall occur which results in the acceleration of
      the maturity of any indebtedness of the Maker; or

(c)   the Maker shall fail to pay any principal or interest hereunder, in each
      case when the same becomes due and payable, and such failure continues
      unremedied for fifteen days after such amount was due and payable; or

(d)   an "Event of Default" as defined in the Loan Agreement shall occur and be
      continuing,

then, all unpaid principal of and interest on this Note shall become immediately
due and payable, without presentment, demand, protest or further notice of any
kind, all of which are hereby expressly waived by the Maker, and the Payee may
proceed to protect and enforce its rights hereunder by an action at law, suit in
equity or other appropriate proceeding, in the Payee's sole discretion. The
Maker shall forthwith notify the Payee, in writing, of the occurrence of any
event which is, or with the passage of time would be, an Event of Default.

      In the event of any failure to make a full and timely payment of any
amount due under this Note, or if any other event rendering the entire unpaid
principal amount of this Note immediately due and payable shall occur, the Maker
will pay to the Payee such further amount as shall be sufficient to cover all
costs and expenses directly or indirectly incurred in connection with any action
relating to collection of this Note and/or the enforcement of the Payee's rights
with respect to, or the administration, supervision, preservation, protection
of, or realization upon, any property securing payment hereof (including
expenses incurred in the defense of counterclaims whether or not related to this
Note), including but not limited to attorneys' fees, expenses and disbursements.

      No course of dealing and no delay or failure on the part of the Payee in
exercising any right, power or remedy hereunder shall operate as a waiver
thereof or otherwise prejudice any of the Payee's rights, powers and remedies,
and no single or partial exercise of a right, power or remedy shall preclude a
further exercise thereof or the exercise of another right, power or remedy. The
Maker hereby waives presentment for payment, demand, protest, notice of dishonor
and nonpayment, and all other notices and demands in connection with the
delivery, acceptance, performance, default, endorsement or guarantee of this
Note. The Maker shall not have any right to offset any payments due to the Payee
hereunder against any amounts claimed to be owed to Payee hereunder or
otherwise, but shall be required to continue to make all payments to the Payee
when due hereunder.

      This Note shall be governed by and construed in accordance with the
internal laws of the Commonwealth of Massachusetts without giving effect to the
conflict of laws principles thereof. Any provisions hereof which may prove
unenforceable under any law shall not affect the validity of any other
provisions hereof.

      The Maker hereby irrevocably waives all right to trial by jury in any
action,


                                      -2-
<PAGE>

proceeding or counterclaim (whether based on contract, tort or otherwise)
arising out of or relating to this Note or the negotiation, administration,
performance or enforcement hereof.

      This Note may not be altered or amended except by a writing duly signed by
the party against whom such alteration or amendment is sought to be enforced.
All of the terms and provisions of this Note shall be applicable to and binding
upon each and every maker, holder, endorser, surety, guarantor and all other
persons who are or may become liable for the payment hereof and their respective
successors or assigns.

      IN WITNESS WHEREOF, the undersigned has duly caused this Note to be
executed and delivered as of the date and year first above written.

                                      HYBRIDON, INC



                                      By:
                                             ---------------------------------
                                      Name:  Robert G. Andersen
                                      Title: Vice President, Operations
                                                and Planning

                                      -3-


                              TERM PROMISSORY NOTE


$500,000                                                      September 27, 1999
                                                          Milford, Massachusetts


      FOR VALUE RECEIVED, the undersigned, Hybridon, Inc., a Delaware
corporation (the "Maker"), hereby promises to pay to E. Andrews Grinstead III
(the "Payee"), or his assigns, the principal sum of Five Hundred Thousand
Dollars ($500,000), together with interest thereon from the date hereof at the
following rate (the "Rate of Interest") (calculated on the basis of a 360-day
year of twelve 30-day months) on the unpaid principal balance hereunder: at the
option of the Lender, either (a) 12% per annum, payable in cash or (b) 15% per
annum, payable in common stock of the Payee at the rate of fifty cents ($0.50)
per share. Interest on this Note shall be due and payable monthly in arrears on
the first business day of each month commencing on October 1, 1999 until March
1, 2000. Notwithstanding the foregoing, this Note may be revised or extended as
provided in the Loan Agreement dated September 1, 1999 between the Maker and the
Payee ("Loan Agreement"). All cash payments under this Note shall be made in
lawful money of the United States in immediately available funds. Any common
stock of the Maker issued under this Note shall bear an appropriate securities
law legend and the issuance thereof shall be subject to the Payee's execution
and delivery of an appropriate private placement agreement.

      Maker may prepay all or any portion of the principal amount outstanding
hereunder without premium or penalty at any time. All prepayments of the
principal amount outstanding hereunder or any portion thereof shall be made
together with the payment of all interest accrued on the amount repaid through
the date of such prepayment.

      If any of the following events ("Events of Default") shall occur and be
continuing:

(a)   the Maker shall generally not pay its debts as such debts become due, or
      shall admit in writing its inability to pay its debts generally, or shall
      make a general assignment for the benefit of creditors; or any proceeding
      shall be instituted by or against the Maker seeking to adjudicate it a
      bankrupt or insolvent, or seeking liquidation, winding up, reorganization,
      arrangement, adjustment, protection, relief, or composition of it or its
      debts under any law relating to bankruptcy, insolvency or reorganization
      or relief of debtors, or seeking the entry of an order for relief or the
      appointment of a receiver, trustee, or other similar official for it or
      for any substantial part of its property and, in the case of any such
      proceeding instituted against it (but not instituted by it) that is being
      diligently contested by it in good faith, either such proceeding shall
      remain undismissed or unstayed for a period of 60 days or any of the
      actions sought in such proceeding (including, without limitation, the
      entry of an order for relief against, or the appointment of a receiver,
      trustee, custodian or other similar official for, it or any substantial
      part of its property) shall occur; or the Maker shall take any corporate
      action to authorize any of the actions set forth above; or

(b)   any event or condition shall occur which results in the acceleration of
      the maturity of any


                                      -1-
<PAGE>

      indebtedness of the Maker; or

(c)   the Maker shall fail to pay any principal or interest hereunder, in each
      case when the same becomes due and payable, and such failure continues
      unremedied for fifteen days after such amount was due and payable; or

(d)   an "Event of Default" as defined in the Loan Agreement shall occur and be
      continuing,

then, all unpaid principal of and interest on this Note shall become immediately
due and payable, without presentment, demand, protest or further notice of any
kind, all of which are hereby expressly waived by the Maker, and the Payee may
proceed to protect and enforce its rights hereunder by an action at law, suit in
equity or other appropriate proceeding, in the Payee's sole discretion. The
Maker shall forthwith notify the Payee, in writing, of the occurrence of any
event which is, or with the passage of time would be, an Event of Default.

      In the event of any failure to make a full and timely payment of any
amount due under this Note, or if any other event rendering the entire unpaid
principal amount of this Note immediately due and payable shall occur, the Maker
will pay to the Payee such further amount as shall be sufficient to cover all
costs and expenses directly or indirectly incurred in connection with any action
relating to collection of this Note and/or the enforcement of the Payee's rights
with respect to, or the administration, supervision, preservation, protection
of, or realization upon, any property securing payment hereof (including
expenses incurred in the defense of counterclaims whether or not related to this
Note), including but not limited to attorneys' fees, expenses and disbursements.

      No course of dealing and no delay or failure on the part of the Payee in
exercising any right, power or remedy hereunder shall operate as a waiver
thereof or otherwise prejudice any of the Payee's rights, powers and remedies,
and no single or partial exercise of a right, power or remedy shall preclude a
further exercise thereof or the exercise of another right, power or remedy. The
Maker hereby waives presentment for payment, demand, protest, notice of dishonor
and nonpayment, and all other notices and demands in connection with the
delivery, acceptance, performance, default, endorsement or guarantee of this
Note. The Maker shall not have any right to offset any payments due to the Payee
hereunder against any amounts claimed to be owed to Payee hereunder or
otherwise, but shall be required to continue to make all payments to the Payee
when due hereunder.

      This Note shall be governed by and construed in accordance with the
internal laws of the Commonwealth of Massachusetts without giving effect to the
conflict of laws principles thereof. Any provisions hereof which may prove
unenforceable under any law shall not affect the validity of any other
provisions hereof.

      The Maker hereby irrevocably waives all right to trial by jury in any
action, proceeding or counterclaim (whether based on contract, tort or
otherwise) arising out of or relating to this Note or the negotiation,
administration, performance or enforcement hereof.

      This Note may not be altered or amended except by a writing duly signed by
the party against whom such alteration or amendment is sought to be enforced.
All of the terms and


                                      -2-
<PAGE>

provisions of this Note shall be applicable to and binding upon each and every
maker, holder, endorser, surety, guarantor and all other persons who are or may
become liable for the payment hereof and their respective successors or assigns.

      IN WITNESS WHEREOF, the undersigned has duly caused this Note to be
executed and delivered as of the date and year first above written.

                                         HYBRIDON, INC.



                                         By:
                                                -------------------------------
                                         Name:  Robert G. Andersen
                                         Title: Vice President, Operations
                                                    and Planning


                                      -3-

<TABLE> <S> <C>


<ARTICLE>                     5
<CURRENCY>                                           U.S. DOLLARS

<S>                             <C>
<PERIOD-TYPE>                                               9-MOS
<FISCAL-YEAR-END>                                     DEC-31-1999
<PERIOD-START>                                        JAN-01-1999
<PERIOD-END>                                          SEP-30-1999
<EXCHANGE-RATE>                                                 1
<CASH>                                                    500,179
<SECURITIES>                                                    0
<RECEIVABLES>                                             838,852
<ALLOWANCES>                                                    0
<INVENTORY>                                                     0
<CURRENT-ASSETS>                                        1,441,216
<PP&E>                                                 21,115,614
<DEPRECIATION>                                         14,162,190
<TOTAL-ASSETS>                                          9,193,263
<CURRENT-LIABILITIES>                                  11,980,721
<BONDS>                                                 1,719,523
                                      16,261
                                                     0
<COMMON>                                                    6,410
<OTHER-SE>                                             (4,529,652)
<TOTAL-LIABILITY-AND-EQUITY>                            9,193,263
<SALES>                                                 4,643,842
<TOTAL-REVENUES>                                        5,282,516
<CGS>                                                           0
<TOTAL-COSTS>                                          13,053,023
<OTHER-EXPENSES>                                                0
<LOSS-PROVISION>                                                0
<INTEREST-EXPENSE>                                        561,949
<INCOME-PRETAX>                                        (8,332,456)
<INCOME-TAX>                                                    0
<INCOME-CONTINUING>                                    (8,332,456)
<DISCONTINUED>                                                  0
<EXTRAORDINARY>                                                 0
<CHANGES>                                                       0
<NET-INCOME>                                           (8,332,456)
<EPS-BASIC>                                               (0.74)
<EPS-DILUTED>                                               (0.74)


</TABLE>


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