Document:

<PAGE>

                                                                  EXECUTION COPY

                                                                    Exhibit 10.1

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

                   RESEARCH COLLABORATION AND OPTION AGREEMENT

                                 by and between

                                 HYBRIDON, INC.

                                       and

                   NOVARTIS INTERNATIONAL PHARMACEUTICAL LTD.

<PAGE>

                   RESEARCH COLLABORATION AND OPTION AGREEMENT

      This Research Collaboration and Option Agreement (this "Agreement") is
made this 31st day of May, 2005 (the "Effective Date") by and between Hybridon,
Inc., a Delaware corporation with principal offices at 345 Vassar Street,
Cambridge, Massachusetts 02139 ("Hybridon") and Novartis International
Pharmaceutical Ltd., a Bermuda corporation with principal offices at Hurst Holme
12, Trott Road, Hamilton, HM11 Bermuda ("Novartis"). Hybridon and Novartis are
sometimes referred to herein individually as a "Party" or collectively as the
"Parties."

      Capitalized terms used but not defined in this Agreement shall have the
meanings provided in the License, Development and Commercialization Agreement by
and between Hybridon and Novartis of even date herewith (the "License
Agreement").

                                  INTRODUCTION

      WHEREAS, Hybridon possesses expertise in discovering and developing novel
therapeutics based on IMO (as defined below) compounds;

      WHEREAS, Novartis and its Affiliates (as defined below) possess expertise
in discovering, developing, manufacturing, marketing and selling pharmaceuticals
worldwide;

      WHEREAS, the Parties desire to enter into a collaboration with the
objective of identifying IMO Candidates and generating IMO Leads (each of "IMO
Candidates" and "IMO Leads" as defined below) for use in the Research Field of
Use (the "Collaboration"); and

      WHEREAS, the Parties are entering into the License Agreement, pursuant to
which Novartis and its Affiliates shall have an exclusive license to
commercialize Products based on certain of the IMO Candidates in the Commercial
Field of Use upon the terms set forth in the License Agreement if Novartis
exercises its Commercialization Option hereunder (each of "Affiliates,"
"Commercial Field of Use," "Commercialization Option," "License Agreement,"
"Products," and "Research Field of Use" as defined below);

      NOW THEREFORE, in consideration of the mutual covenants set forth in this
Agreement, and other good and valuable consideration, the Parties agree as
follows:

<PAGE>

                                    ARTICLE I

                                   DEFINITIONS

      1.1. "ACCEPTANCE CRITERIA" shall mean the specifications for IMO
Candidates for acceptance into the CSP Phase set forth in the Research Plan.

      1.2. "ACQUISITION INTELLECTUAL PROPERTY" shall mean (a) Patents or
Know-How held or otherwise controlled by an Acquisition Affiliate immediately
prior to the Acquisition Event between Hybridon and such Acquisition Affiliate
(as defined in Section 1.3 below), other than Patents that do not specifically
relate to drug delivery or formulation technology held or otherwise controlled
by any such Acquisition Affiliate that would, but for a license granted
hereunder, be infringed by the development or commercialization of IMO
Candidates or IMO Leads and (b) Patents or Know-How developed or acquired and
controlled by an Acquisition Affiliate after the Acquisition Event between
Hybridon and such Acquisition Affiliate that specifically relate to drug
delivery or formulation technology, which Patents or Know-How are not developed
or acquired through the use of, or as an improvement to, any Hybridon
Intellectual Property or Hybridon Background Intellectual Property Controlled
(other than through an Acquisition Affiliate) by Hybridon.

      1.3. "ACQUISITION EVENT" shall mean any merger or other acquisition
between Hybridon and a Third Party occurring after the Effective Date and
pursuant to which such Third Party becomes an Affiliate of Hybridon, so long as
following such merger or acquisition Hybridon does not control and is not merged
with or into such Affiliate (an "Acquisition Affiliate").

      1.4. "ADDITIONAL INDICATION" shall have the meaning set forth in Section
4.1 of the License Agreement.

      1.5. "AFFILIATE" means any Person who directly or indirectly controls or
is controlled by or is under common control with a Party. For purposes of this
definition, "control" or "controlled" means ownership directly or through one or
more Affiliates, of fifty percent (50%) or more of the shares of stock entitled
to vote for the election of directors, in the case of a corporation, or fifty
percent (50%) or more of the equity interest in the case of any other type of
legal entity, status as a general partner in any partnership, or any other
arrangement whereby a

                                  PAGE 2 OF 54
<PAGE>

Party controls or has the right to control the Board of Directors or equivalent
governing body of a corporation or other entity, or the ability to cause the
direction of the management or policies of a corporation or other entity. The
Parties acknowledge that in the case of certain entities organized under the
laws of certain countries outside of the United States, the maximum percentage
ownership permitted by law for a foreign investor may be less than fifty percent
(50%), and that in such case such lower percentage shall be substituted in the
preceding sentence, provided, that such foreign investor has the power to direct
the management and policies of such entity. For the purposes of this Agreement,
Novartis Institute for Functional Genomics, Inc. and Friedrich Miescher
Institute for Biomedical Research shall be deemed to be Affiliates of Novartis.

      1.6. "CHEMICALLY MODIFY" OR "CHEMICAL MODIFICATION" shall mean the
modification of an IMO that [**].

      1.7. "COLLABORATION" shall have the meaning set forth in the preamble to
this Agreement.

      1.8. "COMMERCIAL FIELD OF USE" shall mean the prophylaxis, palliation,
diagnosis and treatment of the Initial Indications and Additional Indications by
Products via any route of administration.

      1.9. "COMMERCIALIZATION EXERCISE NOTICE" shall have the meaning set forth
in Section 4.2.2 hereof.

      1.10. "COMMERCIALIZATION OPTION" shall have the meaning set forth in
Section 4.2.1 hereof.

      1.11. "CONFIDENTIAL INFORMATION" shall have the meaning set forth in
Section 5.1 hereof.

      1.12. "CONSUMER PRICE INDEX" shall mean the Consumer Price Index - Urban
Wage Earners and Clerical Workers, U.S. City Average, All Items, 1982-84 = 100,
published by the United States Department of Labor, Bureau of Labor Statistics
(or its successor equivalent index).

      1.13. "CONTROLLED" shall mean, with respect to intellectual property, the
legal authority of a Party (either directly or through an Affiliate) to grant
the licenses or sublicenses of

                                  PAGE 3 OF 54
<PAGE>

intellectual property rights as and to the extent provided herein, or to
otherwise disclose proprietary or trade secret information as and to the extent
provided herein, without breaching the terms of any agreement with a Third
Party, knowingly infringing upon the intellectual property rights of a Third
Party, or misappropriating the proprietary or trade secret information of a
Third Party.

      1.14. "CRITICAL ISSUE" shall have the meaning set forth in Section 2.5.2
hereof.

      1.15. "CSP PHASE RESEARCH" shall have the meaning set forth in Section
2.3.2 hereof.

      1.16. "EFFECTIVE DATE" shall mean the effective date of this Agreement as
set forth on the first page hereof.

      1.17. "EPIGENESIS" shall mean EpiGenesis Pharmaceuticals, Inc.

      1.18. "EPIGENESIS AGREEMENT" shall mean that certain Development and
License Agreement, dated as of August 9, 2000, between Hybridon and EpiGenesis.

      1.19. "EXCLUDED ANTISENSE IP" shall mean oligonucleotides or
oligonucleotide analogs or mimics thereof that (a) are targeted to a specific
sequence of RNA and (b) the primary mechanism of action of which is to hybridize
to such sequence of RNA and through such hybridization to modulate the
production of the targeted gene product, provided, that such oligonucleotides or
oligonucleotide analogs or mimics thereof [**] proprietary to Hybridon[**].

      1.20. "EXTENDED RENEWAL PERIOD" shall have the meaning set forth in
Section 2.1.3 hereof.

      1.21. "FDA" shall mean the United States Food and Drug Administration, and
any successor agency serving the same function.

      1.22. "FPFV" shall mean the first visit of the first patient or first
healthy human volunteer participating in a clinical trial with respect to an IMO
Lead.

      1.23. "FTE" shall mean the equivalent of the work of one (1) Hybridon
scientist or other Hybridon project managerial professional, full time for one
year, which equates to a total of [**] weeks or [**] hours per year on or
directly related to the Research Program and shall exclude (a) managerial
activities (other than project and research management activities as

                                  PAGE 4 OF 54
<PAGE>

described below) and (b) assistance with the manufacturing and supply activities
described in Sections 2.3.2(b) and 2.3.3(b) hereof. Work on or directly related
to the Research Program may include, but is not limited to, experimental
laboratory work, work related to Proof of Concept studies, project and research
management, activities directed toward evaluation of the commercial potential of
an IMO Candidate, recording and writing up results, reviewing literature and
references, holding scientific discussions, and carrying out JRC duties.

      1.24. "FTE RATE" shall mean a rate of [**] U.S. Dollars (U.S. $[**]) per
FTE, to be prorated on a daily basis if necessary (per annum amount to be
divided by [**] to produce the rate per whole day consisting of [**]). For the
avoidance of doubt, such rate shall include all travel expenses, which shall not
be invoiced separately. For each calendar year commencing with the 2007 calendar
year, the FTE Rate shall be subject to cost of living increases on an annual
basis, based on the increase in the Consumer Price Index as of the then most
recent December 31 over the Consumer Price Index on December 31, 2004, it being
understood that the FTE Rate to be used as the basis for each such increase, if
any, shall be $[**], and not the most recent FTE Rate then in effect.

      1.25. "HYBRIDON BACKGROUND INTELLECTUAL PROPERTY" shall mean all Patents
and Know-How Controlled by Hybridon as of the Effective Date or at any time
during the Term that are necessary or useful for the Parties or their Affiliates
or sublicensees to exploit the licenses contemplated or to carry out the
activities contemplated hereunder and that are not otherwise Hybridon
Intellectual Property or Joint Intellectual Property. Notwithstanding the
foregoing, "Hybridon Background Intellectual Property" shall exclude any
Acquisition Intellectual Property.

      1.26. "HYBRIDON INTELLECTUAL PROPERTY" shall mean all Hybridon Patents and
Hybridon Know-How, but explicitly excluding Joint Intellectual Property and any
Acquisition Intellectual Property.

      1.27. "HYBRIDON KNOW-HOW" shall mean all Know-How Controlled by Hybridon
relating to the IMO Candidates and IMO Leads but explicitly excluding Joint
Know-How and any Know-How included in the Acquisition Intellectual Property, as
of the Effective Date or at any time during the Term.

                                  PAGE 5 OF 54
<PAGE>

      1.28. "HYBRIDON PATENTS" shall mean any Patents Controlled by Hybridon
that would, but for a license granted hereunder, be infringed by making, having
made, using, having used, researching, having researched, developing, having
developed, commercializing, having commercialized, manufacturing, having
manufactured, promoting, having promoted, selling, having sold, distributing,
having distributed, marketing, having marketed, importing, having imported,
exporting or having exported IMO Candidates or IMO Leads, but explicitly
excluding Joint Patents and any Patents included in the Acquisition Intellectual
Property, as in effect on the Effective Date or at any time during the Term. The
Hybridon Patents are set forth on Schedule 1.28 hereto, as amended from time to
time.

      1.29. "IMO" shall mean an immunomodulatory oligonucleotide containing a
motif proprietary to Hybridon and designed to agonize toll-like receptor 9
(directly or indirectly) for the primary purpose of inducing or modulating an
immune response.

      1.30. "IMO CANDIDATE" shall mean an IMO supplied by Hybridon in accordance
with Section 2.3.1(a) and that is designated by Novartis, in its sole
discretion, as meeting the Acceptance Criteria and for inclusion in the CSP
Phase Research.

      1.31. "IMO LEAD" shall have the meaning set forth in Section 2.3.2 hereof
and shall include any Improvements thereto. IMO Leads shall continue to be IMO
Candidates for purposes hereof.

      1.32. "IMPROVEMENTS" shall mean any enhancements to the formulation,
ingredients, preparations, presentation, means of delivery, dosage, packaging,
or manufacturing process of an IMO Lead, IMO Candidate or Product, but excluding
as to all of the foregoing any Chemical Modification to an IMO Lead, IMO
Candidate or the IMO Lead or IMO Candidate component of a Product. For the
avoidance of doubt, any salt form of an IMO Lead, IMO Candidate or IMO included
in a Product shall be deemed an Improvement for purposes hereof.

      1.33. "INDEMNIFIED PERSON" shall have the meaning set forth in Section 7.3
hereof.

      1.34. "INDEMNIFYING PARTY" shall have the meaning set forth in Section 7.3
hereof.

      1.35. "INITIAL INDICATIONS" shall mean all human allergic and/or
respiratory diseases, but specifically excluding oncology and infectious
diseases (other than cystic fibrosis, asthma

                                  PAGE 6 OF 54
<PAGE>

and chronic obstructive pulmonary disease pathologies, in each case resulting
from infectious diseases) and systemic autoimmune diseases.

      1.36. "INITIAL RESEARCH TERM" shall have the meaning set forth in Section
2.1.1 hereof.

      1.37. "INVOICE" shall mean an invoice in the form attached hereto as
Schedule 1.37.

      1.38. "JOINT INTELLECTUAL PROPERTY" shall mean Joint Know How and Joint
Patents.

      1.39. "JOINT KNOW-HOW" shall mean all Know-How developed, produced, or
identified jointly by Hybridon and Novartis or their respective Affiliates
pursuant to the Research Program and/or under the Research Plan including, but
not limited to, such Know-How related to joint Improvements or to the
identification, generation, modification and/or characterization of IMO
Candidates and IMO Leads made jointly by the Parties.

      1.40. "JOINT PATENTS" shall mean all Patents for inventions conceived
jointly by Hybridon and Novartis or their respective Affiliates that arise out
of the activities performed under the Research Program including, but not
limited to, inventions relating to joint Improvements or to the identification,
generation, modification and/or characterization of IMO Candidates and IMO Leads
made jointly by the Parties. After the filing of the first Joint Patent, if any,
a list of Joint Patents shall be appended hereto as Schedule 1.40, which will be
updated periodically to reflect additional Joint Patents thereafter.

      1.41. "JRC" shall have the meaning set forth in Section 2.4 hereof.

      1.42. "KNOW-HOW" shall mean all data, technical information, material,
experience, know-how, inventions (whether or not patented), trade secrets,
processes and methods in any form discovered, developed or applied (with the
consent of its owner) and Controlled by either Party or its Affiliates,
excluding Patents.

      1.43. "LICENSE AGREEMENT" shall have the meaning set forth in the preamble
to this Agreement.

      1.44. "LOSS" shall have the meaning set forth in Section 7.1 hereof.

      1.45. "NOVARTIS INTELLECTUAL PROPERTY" shall mean all Novartis Patents and
Novartis Know-How, but explicitly excluding Joint Intellectual Property.

                                  PAGE 7 OF 54
<PAGE>

      1.46. "NOVARTIS KNOW-HOW" shall mean all Know-How relating to
immunomodulatory oligonucleotides Controlled by Novartis on the Effective Date
or at any time during the Term, but explicitly excluding Joint Know-How,
Hybridon Intellectual Property and Hybridon Background Intellectual Property.

      1.47. "NOVARTIS PATENTS" shall mean any Patents relating to
immunomodulatory oligonucleotides Controlled by Novartis on the Effective Date
or at any time during the Term, but explicitly excluding Joint Patents, Hybridon
Intellectual Property and Hybridon Background Intellectual Property.

      1.48. "NOVARTIS RESEARCH LICENSE" shall have the meaning set forth in
Section 4.1.2 hereof.

      1.49. "OPTION TERM" shall mean the Research Term and a period of [**]
thereafter, provided that in no event shall the Option Term extend beyond the
date that is [**] after the Effective Date without the consent of Hybridon,
which consent shall not be unreasonably withheld.

      1.50. "PATENTS" shall mean all existing patents and patent applications
and all patent applications hereafter filed, including any continuation,
continuation-in-part, divisional, provisional or any substitute applications,
any patent issued with respect to any such patent applications, any reissue,
reexamination, renewal or extension (including any supplementary protection
certificate) of any such patent, and any confirmation patent or registration
patent or patent of addition based on any such patent, and all foreign
counterparts of any of the foregoing.

      1.51. "PERSON" shall mean any individual, corporation, partnership,
association, joint-stock company, trust, unincorporated organization or
government or political subdivision thereof.

      1.52. "PROOF OF CONCEPT" shall mean the scientific study of the mechanism
of action of an IMO Lead conducted in man, which supports Novartis'
decision-making about the value of the IMO Lead as a development candidate.

      1.53. "POC PHASE RESEARCH" shall mean research related to the technical
development of IMO Leads leading to human clinical trials, as well as all human
clinical trials through the end of Proof of Concept clinical trials.

                                  PAGE 8 OF 54
<PAGE>

      1.54. "PRODUCT" shall mean a pharmaceutical product including, conjugated
to, or comprised of an IMO Lead with or without other active ingredients in
finished dosage form, ready for administration to the ultimate consumer, and any
Improvements thereto.

      1.55. "PROVIDING PARTY" shall have the meaning set forth in Section 5.1
hereof.

      1.56. "RECEIVING PARTY" shall have the meaning set forth in Section 5.1
hereof.

      1.57. "RENEWAL NOTICE" shall have the meaning set forth in Section 2.1.2
hereof.

      1.58. "RENEWAL PERIOD" shall have the meaning set forth in Section 2.1.2
hereof.

      1.59. "RESEARCH COSTS" shall mean all research costs (internal or
external, including manufacturing costs) incurred by a Party in performing such
Party's obligations under the Research Program in accordance with the Research
Plan, and, in the case of Hybridon, any such costs not contemplated by the
Research Plan for which Hybridon has obtained prior written approval from
Novartis which are evidenced by a written invoice, contract or other document
provided by a Third Party.

      1.60. "RESEARCH FIELD OF USE" shall mean the prophylaxis, palliation,
diagnosis and treatment of human diseases by pharmaceutical products via any
route of administration.

      1.61. "RESEARCH PLAN" shall have the meaning set forth in Section 2.2.1
hereof.

      1.62. "RESEARCH PROGRAM" shall mean all research activities undertaken
under this Agreement associated with the identification, generation,
modification and/or characterization of IMO Candidates and IMO Leads, including,
without limitation, all CSP Phase Research activities, which shall be performed
in connection with the Research Plan.

      1.63. "RESEARCH TERM" shall have the meaning set forth in Section 2.1.1
hereof.

      1.64. "SUBSTITUTE IMO LEAD" shall mean any IMO Candidate chosen by
Novartis as a substitute for an abandoned IMO Lead. Substitute IMO Leads, if
any, shall be considered IMO Leads for all purposes hereof, and all references
to the term "IMO Lead" shall be deemed to include any and all Substitute IMO
Leads. Abandoned IMO Leads shall, upon abandonment, cease to be IMO Leads but
shall remain IMO Candidates.

                                  PAGE 9 OF 54
<PAGE>

      1.65. "TERM" shall have the meaning set forth in Section 9.1 hereof.

      1.66. "TERRITORY" shall mean the entire world.

      1.67. "TEST SAMPLE" shall have the meaning set forth in Section 2.3.1
hereof, but shall exclude the following immunomodulatory oligonucleotides: [**].

      1.68. "THIRD PARTY" shall mean any Person that is not a Party or an
Affiliate of either Party.

                                   ARTICLE II

                                RESEARCH PROGRAM

      2.1. RESEARCH TERM.

                  2.1.1. Initial Research Term. The initial term of the Research
Program will commence on the Effective Date and continue for a period of two (2)
years, unless earlier terminated in accordance with the provisions hereof (the
"Initial Research Term"). The Initial Research Term, together with any and all
extensions under Section 2.1.2, 2.1.3, or 2.1.4, shall be referred to as the
"Research Term."

                  2.1.2. Extension of Research Term. Unless earlier terminated
in accordance with the provisions hereof, the Research Term may be extended
beyond the Initial Research Term for [**] (the "Renewal Period"), in the sole
discretion of Novartis, upon the provision of written notice to Hybridon not
later than [**] prior to the end of the Initial Research Term ("Renewal
Notice").

                  2.1.3. Extension in Event of PoC Phase Research Clinical Trial
or Volunteer Study Clinical Trial. In the event that Novartis extends the
Research Term in accordance with Section 2.1.2 and an active clinical trial that
is part of PoC Phase Research is ongoing at the end of the Renewal Period, the
term of the Research Program will automatically extend until completion of (a)
such clinical trial that is part of such PoC Phase Research, if such clinical
trial is designed to establish Proof of Concept, or (b) in the case of such
clinical trial that is part of PoC Phase Research but that is not designed to
establish Proof of Concept, the related clinical trial that is part of PoC Phase
Research and that is designed to establish Proof of Concept (the

                                 PAGE 10 OF 54
<PAGE>

"Extended Renewal Period"); provided that in no event shall the Extended Renewal
Period or the Option Term extend beyond the date that is [**] after the
Effective Date without the consent of Hybridon, which consent shall not be
unreasonably withheld.

                  2.1.4. Continuation of Research Program Upon Option Exercise.
In the event that Novartis exercises the Commercialization Option, this
Agreement shall, subject to the following sentence or as otherwise specified
herein, continue in accordance with its terms (including, without limitation,
the provisions of Section 2.3.3(b) hereof) and shall remain in effect until the
date that is [**] after the Effective Date or such longer period to which
Hybridon consents (which consent shall not be unreasonably withheld), unless
earlier terminated in accordance with the provisions hereof. Beginning upon the
Effective Date of the License Agreement, the PoC Phase Research to be performed
pursuant to Section 2.3.3(a) hereof shall be performed under, and governed by
the terms of, the License Agreement.

      2.2. RESEARCH PLAN.

                  2.2.1. Research Plan. Attached as Schedule 2.2.1 hereto is an
initial work plan identifying: (a) the Acceptance Criteria; (b) the
responsibilities of each Party with respect to research to be conducted prior to
the CSP Phase Research; and (c) the appropriate resources of each Party to be
committed with respect to research to be conducted prior to the CSP Phase
Research. No later than [**] after the Effective Date, Novartis, in consultation
with Hybridon, will prepare an overall research plan for the CSP Phase Research
to be conducted pursuant to the Research Program identifying: (i) the Acceptance
Criteria; (ii) the responsibilities of each Party with respect to the CSP Phase
Research to be conducted; (iii) the appropriate resources of each Party to be
committed with respect to the CSP Phase Research; and (iv) the research
activities, studies, developmental milestones, performance criteria, and
timeframes for work to be completed by each Party with respect to the CSP Phase
Research), which the Parties will submit to the JRC for final approval at the
first meeting of the JRC (such research plan, as approved by the JRC and as
amended from time-to-time, the "Research Plan," except that any changes to the
Acceptance Criteria must be made upon the mutual written consent of the Parties,
such consent not to be unreasonably withheld). The Research Plan and any
amendments thereto shall be included on Schedule 2.2.1 hereto.

                                 PAGE 11 OF 54
<PAGE>

                  2.2.2. Plan Review. The Research Plan will be reviewed and
approved by the JRC shortly after the Effective Date. The JRC may modify the
Research Plan as appropriate; provided, that no modified Research Plan shall
impose substantial resource and/or financial obligations on Hybridon in addition
to those obligations set forth in the initial Research Plan without Hybridon's
consent. Any disagreements between the Parties with respect to modification of
the Research Plan will, subject to the proviso in the immediately preceding
sentence, be resolved in accordance with Section 2.5 of this Agreement.

      2.3. RESEARCH PROGRAM.

               2.3.1. Commencement.

            (a)   Within [**] of the Effective Date, Hybridon, at its own cost,
                  shall generate and supply to Novartis a sufficient number and
                  quantity of IMOs (each a "Test Sample"), to allow evaluation
                  of such Test Samples by the Parties in various in vitro or in
                  vivo assays. In order to facilitate the goals and purposes of
                  the Research Program, Hybridon shall use commercially
                  reasonable efforts to supply Novartis with Test Samples of
                  those IMOs which, in Hybridon's judgment, have the greatest
                  chance (as compared to other IMOs) of meeting the Acceptance
                  Criteria. Each such Test Sample shall be accompanied by all
                  data generated by Hybridon with respect thereto and shall not
                  be required to be materially in excess of the quantity
                  necessary to complete such assays (currently estimated to be
                  up to approximately five (5) grams of each IMO). Based on the
                  results of its evaluation, Novartis, in its discretion, which
                  is reasonably exercised, shall determine whether the Test
                  Samples meet the Acceptance Criteria. From those Test Samples
                  meeting the Acceptance Criteria, Novartis shall, in its sole
                  discretion, identify up to [**] IMO Candidates to be included
                  within the CSP Phase Research. Hybridon's obligation to
                  provide IMOs pursuant to this Section 2.3.1(a) shall be
                  satisfied once Hybridon supplies, in accordance with this
                  Section 2.3.1, Test Samples for IMOs, [**] of which Novartis
                  has determined, in its discretion, which is reasonably
                  exercised, meet the Acceptance Criteria; provided that, if,
                  during the Research Term Novartis

                                  PAGE 12 OF 54
<PAGE>

                  requests that Hybridon generate or supply modified or
                  additional IMOs in response to scientific results that
                  Novartis generates during the Research Program, Hybridon shall
                  use commercially reasonable efforts to provide up to [**]
                  additional IMOs, including Test Samples thereof, at Hybridon's
                  expense.

            (b)   The JRC shall direct the conduct of activities under the
                  Research Plan, and Hybridon and Novartis shall collaborate in
                  the conduct of activities under the Research Plan with the
                  Parties having the roles and responsibilities specified in the
                  Research Plan, all as may be deemed appropriate by the JRC.
                  The JRC shall review and coordinate the efforts of the Parties
                  with respect to the Research Plan.

               2.3.2. CSP Phase Research.

            (a)   During the phase of the Research Program culminating in the
                  candidate selection point (the "CSP Phase Research"), the
                  Parties shall evaluate up to [**] IMO Candidates in various in
                  vitro screens and in vivo models such as those described on
                  Schedule 2.3.2 hereof and shall identify IMO Candidates to be
                  included in the PoC Phase Research to be performed under this
                  Agreement (each an "IMO Lead"). Novartis may designate one or
                  more of the IMO Candidates as IMO Leads, but shall not be
                  obligated to include any such IMO Leads in PoC Phase Research
                  to be performed under this Agreement. Notwithstanding the
                  foregoing, in the event Novartis abandons development of an
                  IMO Lead, Novartis may designate a Substitute IMO Lead and
                  advance the Substitute IMO Lead in place of the abandoned IMO
                  Lead.

            (b)   Hybridon shall cooperate with Novartis and any Third Party
                  supplier retained by Novartis, in Novartis' sole discretion,
                  to enable Novartis and/or such Third Party supplier to
                  manufacture and supply IMO Candidates meeting Novartis'
                  specifications for use in the CSP Phase Research. Hybridon
                  shall provide to Novartis and any Third Party supplier all

                                  PAGE 13 OF 54
<PAGE>

                  technical information and Hybridon Know-How necessary or
                  useful to allow Novartis and/or such Third Party supplier to
                  manufacture the IMO Candidates. Hybridon will make available
                  to Novartis those persons that are subject to Hybridon's
                  control with technical information or necessary or useful
                  expertise to assist Novartis and/or the Third Party supplier
                  with the manufacturing process. Hybridon will not charge
                  Novartis for any costs associated with the performance of its
                  obligations under this Section 2.3.2(b), including, without
                  limitation, the time spent by Hybridon personnel in providing
                  assistance to Novartis and/or any Third Party supplier. Other
                  than as set forth in this Section 2.3.2(b), Novartis shall be
                  responsible for the costs of such supply and all other
                  contractual obligations to such Third Party supplier.

            (c)   Novartis management will determine, in its reasonable
                  discretion, whether an IMO meets the Acceptance Criteria. In
                  addition, Novartis management will determine, in its sole
                  discretion, whether to terminate the CSP Phase Research with
                  respect to any particular IMO Candidate, whether the CSP Phase
                  Research has been successfully completed and which, if any, of
                  the IMO Candidates to designate as IMO Leads.

               2.3.3. PoC Phase Research.

            (a)   In the event that Novartis designates one or more IMO Lead(s),
                  Novartis will conduct PoC Phase Research on such IMO Lead(s),
                  including, without limitation, studies regarding [**], with at
                  least the primary clinical endpoints for such PoC Phase
                  Research to be determined by the JRC. Novartis will make all
                  regulatory filings in Europe, the U.S. and/or any other
                  jurisdictions necessary to conduct the PoC Phase Research
                  under this Agreement. Novartis shall, for informational
                  purposes only, periodically share information with the members
                  of the JRC regarding the status of the PoC Phase Research
                  performed under this Agreement and summaries of the results
                  thereof. Novartis management will determine, in its sole
                  discretion, whether to continue or cease the PoC Phase
                  Research being conducted

                                 PAGE 14 OF 54
<PAGE>

                  under this Agreement with respect to any IMO Lead and whether
                  to put forward a Substitute IMO Lead in lieu thereof, in which
                  case Novartis shall notify Hybridon of the same in writing.

            (b)   Hybridon shall cooperate with Novartis and any Third Party
                  supplier retained by Novartis, in Novartis' sole discretion,
                  to enable Novartis and/or such Third Party supplier to
                  manufacture and supply IMO Candidates meeting Novartis'
                  specifications for use in the PoC Phase Research. Hybridon
                  shall provide to Novartis and any Third Party supplier all
                  technical information and Hybridon Know-How necessary or
                  useful to allow Novartis and/or such Third Party supplier to
                  manufacture the IMO Candidates. Hybridon will make available
                  to Novartis those persons that are subject to Hybridon's
                  control with technical information or necessary or useful
                  expertise to assist Novartis and/or the Third Party supplier
                  with the manufacturing process. Hybridon will not charge
                  Novartis for any costs associated with the performance of its
                  obligations under this Section 2.3.3(b), including, without
                  limitation, the time spent by Hybridon personnel in providing
                  assistance to Novartis and/or any Third Party supplier. Other
                  than as set forth in this Section 2.3.3(b), Novartis shall be
                  responsible for the costs of such supply and all other
                  contractual obligations to such Third Party supplier.

               2.3.4. Research Diligence. Hybridon shall use commercially
reasonable efforts to fulfill its obligations under the Research Program and
Research Plan. Novartis shall use commercially reasonable efforts, similar to
those used by Novartis or its Affiliates in the research and development of
other products of Novartis or its Affiliates that are of similar commercial
potential and at a similar stage of research or development, to fulfill its
obligations under the Research Plan and the Research Program.

               2.3.5. Submission of Reports. Upon achieving, or failing to
achieve, each scientific or technical milestone specified in the Research Plan,
Hybridon and Novartis will complete and present to the JRC a report containing
detailed summaries of the data related to such milestone. For purposes thereof,
each Party shall provide (or request its Affiliates to

                                 PAGE 15 OF 54
<PAGE>

provide) to the other Party any necessary information (including, without
limitation, Confidential Information) as may be reasonably required to perform
its obligations under this Agreement.

      2.4. JOINT RESEARCH COMMITTEE. Upon execution of this Agreement, Hybridon
and Novartis will establish a joint research committee ("JRC"), which shall
consist of an equal number of executives or scientists as may be designated by
each Party from time to time. The JRC shall initially have six (6) members, with
each Party having the right to appoint three (3) members. Novartis shall have
the right to appoint one of its members as the JRC Committee Chair. The JRC
shall hold its first meeting within [**] of the Effective Date. Thereafter, the
JRC shall meet quarterly, or with such other frequency as may be established by
the JRC (but in no event less often than three (3) times per year), and at such
time and location as may be established by the JRC. The JRC shall have the
following responsibilities:

            (a)   Provide general oversight of, direct the conduct of, and
                  review and coordinate the efforts of the Parties with respect
                  to, the Research Plan, and monitor the progress of the
                  activities carried out pursuant to the Research Plan;

            (b)   Periodically review the overall goals and strategy of the
                  activities to be conducted under the Research Plan;

            (c)   Subject to Section 2.2.2, identify the number of FTEs required
                  for activities to be conducted under the Research Plan and
                  prioritize the allocation of resources dedicated to the
                  Research Plan (including FTEs);

            (d)   Subject to Section 2.2.2, approve and revise, as appropriate,
                  the Research Plan;

            (e)   Revise, as appropriate, performance milestones (other than
                  milestones the achievement of which are the basis for payments
                  to Hybridon under this Agreement or the License Agreement);

            (f)   Review and edit proposed publications related to the Research
                  Plan and/or the Collaboration;

            (g)   Subject to Sections 2.2.1, 2.2.2 and 2.5.2, revise, as
                  appropriate, the

                                 PAGE 16 OF 54
<PAGE>

                  Acceptance Criteria;

            (h)   Resolve any disagreement between the Parties, and discuss and
                  resolve any other relevant issues submitted to it, in
                  accordance with the dispute resolution procedure set forth in
                  Section 2.5 below.

            The JRC shall have the authority to create teams for individual
projects, each of which will meet (via telephone or video conference or in
person) no less frequently than monthly, and which will report to the JRC on its
progress on activities performed with respect to such project. In addition, the
JRC shall also have the authority to create subcommittees as needed.
Notwithstanding the foregoing, the Parties acknowledge that the JRC shall not
have the authority to amend or modify the terms or conditions of this Agreement.
The JRC shall survive until expiration or termination of this Agreement.

      2.5. DECISIONS OF THE JRC; RESOLUTION OF DISPUTES.

               2.5.1. Decisions of the JRC. Each of Hybridon and Novartis shall
have one vote on the JRC. The JRC shall make decisions unanimously where
possible. In the event of a deadlock, Novartis shall have the deciding vote on
all matters except Critical Issues.

               2.5.2. Dispute Resolution. In the event that the JRC is
deadlocked as to any material increase in financial or other resources required
to be expended by Hybridon in connection with the Research Program (a "Critical
Issue"), then the Parties shall attempt to have the issue resolved in accordance
with the dispute resolution mechanism set forth in Section 11.3 hereof.

      2.6. EXCHANGE OF INFORMATION.

               2.6.1. Reports to JRC. Hybridon and Novartis will share
information (including, without limitation, Confidential Information) regarding
the Collaboration and/or activities conducted under the Research Plan with the
members of the JRC no less frequently than quarterly in order to allow such
members to monitor the progress of the Collaboration.

               2.6.2. Restrictions on Use of Know-How. Know-How disclosed by one
Party to the other Party shall be deemed Confidential Information of the
Providing Party subject to the provisions of Article V.

                                 PAGE 17 OF 54
<PAGE>

               2.6.3. Delivery of Know-How. During, and upon conclusion of, the
Research Program, and subject to the provisions of this Section 2.6 and Article
V hereof, Hybridon shall (a) disclose to Novartis all technical information
known to it which constitutes Hybridon Know-How (to the extent licensed under
this Agreement) and Joint Know-How and (b) transfer to Novartis all data and
materials specified in the related Research Plan. Hybridon shall provide all
data both in hard copy form and, if commercially and technically reasonable, in
an electronic form compatible with Novartis' systems; provided that Novartis
shall only reimburse Hybridon's costs of providing data in a form compatible
with its systems so long as Hybridon has provided Novartis with a reasonably
detailed description of such costs and obtained Novartis' prior written approval
to incur such costs. Novartis shall reimburse such pre-approved costs actually
incurred by Hybridon within [**] after receipt by Novartis of Hybridon's Invoice
for the same.

               2.6.4. Background Intellectual Property; Non-Interference.

            (a)   Neither Party shall be entitled to information from the other
                  Party concerning Hybridon Intellectual Property or Novartis
                  Intellectual Property, as applicable, discovered or developed
                  by that Party outside the Research Program; except that
                  Hybridon must disclose to the JRC in a timely manner any and
                  all Hybridon Background Intellectual Property that it uses
                  and/or is relevant to the Research Program, and each Party
                  must disclose to the JRC all Joint Intellectual Property it
                  conceives, discovers or develops under the Research Program.

            (b)   Hybridon will not assert its rights in any Acquisition
                  Intellectual Property, Hybridon Intellectual Property,
                  Hybridon Background Intellectual Property or Joint
                  Intellectual Property, as applicable, and will use best
                  efforts to prevent its licensees, if any, from asserting
                  similar rights licensed by Hybridon to such licensees to block
                  or impede Novartis or its Affiliates or their assignees,
                  licensees or sublicensees from exercising the rights licensed
                  to Novartis herein or in the License Agreement.

                                 PAGE 18 OF 54
<PAGE>

      2.7. PRIMARY DATA ACCESS.

               2.7.1. Recordkeeping. Hybridon and Novartis shall each maintain
records in sufficient detail, and will document in a manner appropriate for
purposes of supporting the filing of potential patent applications, all work
done and results achieved in the performance of the Research Program and the
Research Plan (including, without limitation, all data necessary in the form
required under any applicable governmental regulations).

               2.7.2. Technical Reports. Subject to Article V hereof: (a)
Hybridon shall grant to Novartis access, at reasonable intervals and upon
reasonable notice, to all data (including, without limitation, all primary data
and data contained in laboratory notebooks) generated in the course of
performing its obligations under the Research Program; (b) Novartis shall have
the right, at reasonable intervals, to make copies of such data to use and
transfer as permitted hereunder; and (c) Novartis shall have the right to use
and transfer such data in accordance with the licenses granted hereunder.
Notwithstanding anything to the contrary in this Agreement or the License
Agreement, except in connection with the exercise by Novartis of an Additional
Indication Option under the License Agreement, Novartis shall not disclose to
Hybridon or to the JRC any data relating to indications, uses of IMOs or
improvements to IMOs outside the Commercial Field of Use.

                                   ARTICLE III

                                    PAYMENTS

      3.1. STAFFING AND RESEARCH SUPPORT PAYMENTS.

               3.1.1. Reimbursement of Research Costs. Except for Research Costs
payable by Hybridon pursuant to the first sentence of Sections 2.3.1(a),
2.3.2(b), and 2.3.3(b), Novartis shall be responsible for all Research Costs and
costs incurred in connection with Section 2.6.3 and shall reimburse Hybridon for
actual Research Costs incurred by Hybridon within [**] after receipt by Novartis
of Hybridon's Invoice for the same.

               3.1.2. FTE Allocation. The JRC shall determine the appropriate
number of FTEs to be assigned to perform activities under the Research Plan and
the manner in which such FTEs shall be allocated in order to best achieve the
goals set forth in the Research Plan. The

                                 PAGE 19 OF 54
<PAGE>

Parties agree that such number of FTEs shall not exceed [**] per year. Novartis
shall fund such FTE support as the JRC determines for the period of time
beginning on the date on which the JRC approves the Research Plan and ending on
the date on which the activities under the Research Plan are completed (or upon
the expiration or termination of this Agreement, if earlier). Novartis will
remit to Hybridon an amount equal to the FTE Rate times the number of FTEs
actually carrying out the activities assigned to Hybridon, prorated for the time
period that the work was actually being performed under the Research Plan as set
forth in Section 1.23.

               3.1.3. FTE Payments. Novartis shall make all payments for FTE
support under the Research Plan to Hybridon quarterly in arrears within [**]
after receipt by Novartis of Hybridon's Invoice for the same. All payments shall
be made without deduction for withholding or other similar taxes, in U.S.
dollars to the credit of such bank account as may be designated by Hybridon in
writing to Novartis. Any payments which fall due on a date which is a legal
holiday in Bermuda, Switzerland or the United States may be made on the next
following day which is not a legal holiday in the Bermuda, Switzerland or the
United States.

               3.1.4. Records.

            (a)   Hybridon shall keep accurate records and books of accounts
                  containing all data reasonably required for the calculation
                  and verification of Research Costs and FTEs employed by, or
                  equivalents supplied by, Hybridon for activities performed in
                  accordance with the Research Plan. At Novartis' request,
                  Hybridon shall make those records available during reasonable
                  working hours for review by a recognized independent
                  accounting firm acceptable to both Parties for the sole
                  purpose of verifying the accuracy of those records in the
                  calculation of Research Costs and FTEs. Novartis shall use
                  commercially reasonable efforts to cause the accounting firm
                  to retain all such information in confidence. Subject to
                  Section 3.1.4(b) hereof, such reviews shall be at Novartis'
                  expense and shall be conducted no more frequently than once
                  per year. Notwithstanding the foregoing, in the event Hybridon
                  is required or elects to restate its accounts, Novartis shall
                  be entitled to conduct an additional review pursuant to this
                  Section 3.1.4.

                                 PAGE 20 OF 54
<PAGE>

            (b)   If the audit shows any underpayment or overcharging by any
                  Party, that underpayment or overcharging shall be reported to
                  the JRC and the underpaying or overcharging Party shall remit
                  such underpayment or reimburse such overcompensation (together
                  with interest at the rate of one percent (1%) per annum) to
                  the underpaid or overcharged Party within thirty (30) calendar
                  days of receiving the audit report. Further, if the audit for
                  an annual period shows an underpayment or an overcharge by any
                  Party for such period in excess of five percent (5%) of the
                  amounts properly determined, the underpaying or overcharging
                  Party, as the case may be, shall reimburse the applicable
                  underpaid or overcharged Party, for its respective audit fees
                  and reasonable out-of-pocket expenses in connection with said
                  audit, which reimbursement shall be made within [**] of
                  receiving appropriate invoices and other support for such
                  audit-related costs.

      3.2. UPFRONT PAYMENT. A one-time, non-creditable, non-refundable upfront
payment of Four Million U.S. Dollars (U.S. $4,000,000) for access by Novartis to
the Hybridon Intellectual Property related to the IMOs for the Research Term and
Hybridon's participation in the Research Program shall become payable upon
execution hereof. An Invoice for such payment is attached hereto as Schedule 3.2
and shall be deemed delivered pursuant to Section 11.13 hereof upon the
Effective Date and Novartis shall make such upfront payment within [**] days
after the Effective Date.

      3.3. RESEARCH PROGRAM PAYMENTS. In addition to the payments pursuant to
Sections 3.1 and 3.2 above, Novartis shall make the following payments to
Hybridon in connection with the Research Program. Each payment shall be made
within [**] days of Novartis' receipt of the related Hybridon Invoice.

               3.3.1. Renewal Period Payment. In the event that Novartis extends
the Initial Research Term pursuant to Section 2.1.2 hereof, Novartis shall make
a one-time, non-creditable, non-refundable payment of [**] U.S. Dollars (U.S.
$[**]) to Hybridon. Hybridon shall submit its Invoice for the same to Novartis
once Hybridon has received the Novartis Renewal Notice. No payment obligation
shall accrue in respect of an extension of the Renewal Period pursuant to
Section 2.1.3 hereof.

                                 PAGE 21 OF 54
<PAGE>

               3.3.2. IMO Lead Payments. Within [**] of a FPFV with respect to
an IMO Lead, Novartis shall notify Hybridon in writing as to the occurrence of
such FPFV (a "FPFV Notice"). Hybridon shall submit its Invoice for the same to
Novartis once Hybridon has received the FPFV Notice. Upon receipt of such
Invoice, Novartis shall make a one-time, non-creditable (except as otherwise set
forth below in this Section 3.3.2), non-refundable payment of [**] U.S. Dollars
(U.S. $[**]) to Hybridon. Such FPFV Notice and payment shall be required only in
connection with the first [**] IMO Leads and such payment shall not be payable
in connection with a Substitute IMO Lead if such payment was previously made for
the initial IMO Lead replaced by the Substitute IMO Lead. In the event any IMO
Lead is replaced with a Substitute IMO Lead, the Substitute IMO Lead shall not
be considered a separate IMO Lead for the purposes of this Agreement, and all
milestone payments previously paid with respect to such initial IMO Lead shall
be fully creditable as payment for the related Substitute IMO Lead.

                                   ARTICLE IV

                LICENSE, DEVELOPMENT AND COMMERCIALIZATION RIGHTS

      4.1. RESEARCH LICENSE.

               4.1.1. Hybridon Intellectual Property. Subject to the terms of
this Agreement and during the Term, Hybridon hereby grants to Novartis and its
Affiliates an exclusive (subject to Hybridon's retention of rights sufficient to
perform its obligations hereunder and to the rights Hybridon has granted to
EpiGenesis pursuant to the EpiGenesis Agreement), non-transferable (except in
accordance with Section 11.9), and sublicensable license in the Territory under
the Hybridon Intellectual Property and Hybridon's interest in the Joint
Intellectual Property to research and develop IMO Candidates in the Research
Field of Use.

               4.1.2. Hybridon Background Intellectual Property. Subject to the
terms of this Agreement and during the Term, Hybridon hereby grants to Novartis
and its Affiliates a non-exclusive, non-transferable (except in accordance with
Section 11.9), and sublicensable license in the Territory under the Hybridon
Background Intellectual Property to research and develop IMO Candidates in the
Research Field of Use (together with the license granted in Section 4.1.1 above,
the "Novartis Research License").

                                 PAGE 22 OF 54
<PAGE>

               4.1.3. Limitations. Notwithstanding the foregoing, nothing herein
shall give Novartis or its Affiliates the right to, and Novartis shall not (and
shall not permit its Affiliates to) during the term of this Agreement: (i)
Chemically Modify any IMO Candidate or use the Hybridon Intellectual Property to
create any immunomodulatory oligonucleotide that is the same or substantially
structurally equivalent to any IMO Candidate or that is covered by any Valid
Claim in the Hybridon Patents; (ii) conduct any clinical trial designed to
support an indication outside the Commercial Field of Use without Hybridon's
consent; or (iii) prior to Novartis' exercise of the Commercialization Option,
initiate any clinical trial with respect to an IMO Candidate beyond the clinical
trial(s) required to establish Proof of Concept (i.e., initiate any phase II(b)
clinical trial, any phase III clinical trial or any pivotal clinical trial, as
those terms are commonly understood in the pharmaceutical industry).

               4.1.4. Sublicensing. Any sublicense granted by Novartis pursuant
to this Agreement must be granted pursuant to a written agreement that subjects
the sublicensee to not less than the relevant restrictions, limitations and
obligations in this Agreement. Novartis shall remain primarily responsible for
all of its obligations under this Agreement and shall take prompt action to
enforce its rights against its sublicensees should any such sublicensee breach
its obligation to comply with the restrictions, limitations or obligations set
forth in this Agreement. Novartis shall designate Hybridon as a third party
beneficiary if Hybridon is damaged as a result of any breach by a sublicensee of
any relevant restriction, limitation, or obligation pertaining to this
Agreement.

      4.2. COMMERCIALIZATION OPTION.

               4.2.1. Commercialization Option. Novartis has the exclusive right
(the "Commercialization Option") during the Option Term to license exclusively
any and all IMO Candidates, including, without limitation, IMO Leads, for
commercialization of Products in the Commercial Field of Use, under the terms
and conditions set forth in the License Agreement.

               4.2.2. Exercise of Option. Novartis may exercise its
Commercialization Option by delivering to Hybridon written notice of exercise (a
"Commercialization Exercise Notice"). The license grants contemplated by the
License Agreement shall become effective upon the Effective Date of the License
Agreement (as set forth in Section 2.1 thereof). Novartis may exercise the
Commercialization Option during the Option Term. If Novartis does not

                                 PAGE 23 OF 54
<PAGE>

exercise the Commercialization Option during the Option Term, the
Commercialization Option shall expire and have no further force or effect.
Exercise of the Commercialization Option with respect to one IMO Lead licensed
hereunder shall constitute exercise of the Commercialization Option with respect
to any and all IMO Candidates and IMO Leads licensed hereunder.

      4.3. EXCLUSIVITY. During the period beginning on the Effective Date and
throughout the Option Term, and during the entire term of the License Agreement
if Novartis exercises the Commercialization Option: (i) Hybridon shall neither
grant to any Third Party rights to any immunomodulatory oligonucleotide other
than Excluded Antisense IP in the Commercial Field of Use, nor shall Hybridon
develop or commercialize, directly or indirectly, any immunomodulatory
oligonucleotide other than Excluded Antisense IP in the Commercial Field of Use;
and (ii) Hybridon shall neither grant to any Third Party rights to any Test
Sample, IMO Candidate or IMO Lead for any indication, nor shall Hybridon develop
or commercialize, directly or indirectly, any such IMO Candidate or IMO Lead for
any indication. Notwithstanding the foregoing, in the event that Hybridon
provides Novartis with more than [**] Test Samples, the provisions of this
Section 4.3 shall cease to apply upon expiration of the Research Term with
respect to those Test Samples Novartis has determined not to include in the CSP
Phase Research.

                                    ARTICLE V

                                 CONFIDENTIALITY

      5.1. UNDERTAKING. Each Party shall keep confidential, and, other than as
provided herein, shall not use or disclose, directly or indirectly, any trade
secrets, confidential or proprietary information, or any other knowledge,
information, documents or materials, owned, developed or possessed by the other
Party (the "Providing Party"), whether in tangible or intangible form, the
confidentiality of which such other Party takes reasonable measures to protect
(collectively, "Confidential Information"). The Parties hereby agree that, for
the purposes of this Agreement, discussion between the Parties regarding
potential IMO Candidates and IMO Leads will be deemed to be the confidential
information of Novartis.

            (a)   A Party receiving Confidential Information (the "Receiving
                  Party") shall use commercially reasonable efforts not less
                  than those efforts such

                                 PAGE 24 OF 54
<PAGE>

                  Receiving Party uses to protect its own proprietary
                  information to prevent the unauthorized use and disclosure of
                  such information of the Providing Party, and to prevent
                  unauthorized persons or entities from obtaining or using such
                  information.

            (b)   The Receiving Party further agrees to refrain from directly or
                  indirectly taking any action which would constitute or
                  facilitate the unauthorized use or disclosure of Confidential
                  Information. The Receiving Party may disclose Confidential
                  Information to its Affiliates, officers, employees and agents,
                  to authorized licensees and sublicensees, and to
                  subcontractors in connection with the identification,
                  generation, development and manufacture of IMOs, as
                  applicable, to the extent necessary to enable such parties to
                  perform their obligations hereunder or under the applicable
                  license, sublicense or subcontract, as the case may be;
                  provided, however, that such Affiliates, officers, employees,
                  agents, licensees, sublicensees and subcontractors have
                  entered into confidentiality agreements for secrecy and
                  non-use of such Confidential Information offering no less than
                  the protection afforded hereby which by their terms shall be
                  enforceable by injunctive relief at the instance of the
                  Providing Party.

            (c)   The Receiving Party shall be liable for any unauthorized use
                  and disclosure of such information by its Affiliates,
                  officers, employees and agents and any such sublicensees and
                  subcontractors.

      5.2. EXCEPTIONS.

               5.2.1. Non-Confidential Information. Notwithstanding the
foregoing, the provisions of Section 5.1 hereof shall not apply to Confidential
Information that the Receiving Party can establish by clear and convincing
evidence:

            (a)   have entered the public domain without such Receiving Party's
                  breach of any obligation owed to the Providing Party;

            (b)   are or have become known to the Receiving Party from a source
                  other than the Providing Party, other than by breach of an
                  obligation of confidentiality

                                 PAGE 25 OF 54
<PAGE>

                  owed to the Providing Party; or

            (c)   are independently developed by the Receiving Party without
                  reference to or reliance upon knowledge, information,
                  documents or materials of the Providing Party and without
                  breach of this Agreement.

               5.2.2. Other Exceptions. In addition, a Receiving Party may,
notwithstanding the obligations of Section 5.1, disclose Confidential
Information:

            (a)   that the Receiving Party can establish by clear and convincing
                  evidence is permitted to be disclosed by the prior written
                  consent of the Providing Party;

            (b)   that the Receiving Party can establish by clear and convincing
                  evidence is required to be disclosed by the Receiving Party to
                  defend litigation or to comply with applicable laws or
                  regulations (including without limitation disclosure
                  obligations under applicable securities laws or the
                  regulations of any stock exchange or NASDAQ), or in connection
                  with filings with the FDA, the United States Patent and
                  Trademark Office or other similar governmental agencies,
                  provided that the Receiving Party provides prior written
                  notice of such disclosure to the Providing Party and takes
                  reasonable and lawful actions to avoid or minimize the degree
                  of such disclosure; or

            (c)   concerning the existence and terms of this Agreement and the
                  status of transactions described herein, under obligations of
                  confidentiality, to the Receiving Party's existing and
                  potential advisors, investors that are bona fide venture
                  capital or institutional investors that make such investments
                  for the potential financial return and not for strategic
                  purposes (so long as such investor does not have more than
                  $1 billion in world-wide pharmaceutical revenue in the most
                  recently completed calendar year) and any Person considering
                  to acquire Hybridon or a controlling interest in Hybridon (a
                  "Potential Acquirer"). Notwithstanding the foregoing, Hybridon
                  shall not make any such disclosure to any Potential Acquirer
                  (i) until discussions

                                 PAGE 26 OF 54
<PAGE>

                  with such Potential Acquirer progress to a stage at which the
                  Potential Acquirer is engaged in comprehensive due diligence
                  of Hybridon's business and Hybridon has a good faith belief
                  that the consummation of the proposed acquisition has become
                  reasonably likely to occur and (ii) unless the Potential
                  Acquirer has entered into a confidentiality agreement at least
                  as strict as the provisions of this Section 5.2.2(c),
                  designating Novartis as a third party beneficiary and
                  prohibiting the Potential Acquirer from disclosing or using
                  for its own purposes (other than evaluation of the proposed
                  transaction with Hybridon) any such information. Hybridon
                  shall notify Novartis in writing prior to any disclosure
                  pursuant to this Section 5.2.2(c), but shall not be required
                  to disclose the identity of any Potential Acquirer until after
                  consummation or abandonment of the transaction, at which time
                  Hybridon shall provide Novartis with a copy of the
                  confidentiality agreement executed by such Potential Acquirer.

      5.3. PUBLICITY. The Parties will agree upon the timing and content of any
initial press release or other public communications relating to this Agreement
and the transactions contemplated herein.

            (a)   Except as set forth in Section 5.3(b) or to the extent already
                  disclosed in that initial press release or other public
                  communication, no public announcement concerning the existence
                  or the terms of this Agreement or the transactions described
                  herein shall be made, either directly or indirectly, by
                  Hybridon or Novartis, except as may be legally required by
                  applicable laws, regulations, or judicial order, without first
                  obtaining the approval of the other Party and agreement upon
                  the nature, text, and timing of such announcement.

            (b)   Subject to this Article V, a Party may issue press releases or
                  make public communications or otherwise make disclosures that
                  such Party determines to be necessary to comply with
                  applicable law (including disclosure requirements of the U.S.
                  Securities and Exchange Commission, NASDAQ or any stock
                  exchange on which securities issued by such Party are traded);

                                 PAGE 27 OF 54
<PAGE>

                  provided that such Party shall provide the other Party with a
                  copy of the proposed text of such press releases, public
                  communications or disclosure in advance of the scheduled
                  release or publication thereof to afford such other Party a
                  reasonable opportunity to review and comment upon the proposed
                  text.

            (c)   The Party desiring to make any such public announcement shall
                  provide the other Party with a written copy of the proposed
                  announcement in sufficient time (no less than [**] or such
                  shorter period as may be required to enable a Party to comply
                  with applicable law) prior to public release to allow such
                  other Party to comment upon such announcement, prior to public
                  release.

      5.4. SURVIVAL. The provisions of this Article V shall survive for [**]
years after the expiration or termination of this Agreement.

                                   ARTICLE VI

                                   PUBLICATION

      6.1. PUBLICATION. Hybridon and its Affiliates agree not to publish or
publicly present any results, data, or scientific findings with respect to the
Research Program (except in connection with filings with the FDA, the United
States Patent and Trademark Office or other similar governmental entities in
other countries or regions) without the prior written consent of Novartis.
Publication shall be presumed to be impermissible until Novartis shall have
determined, in its sole judgment, that the intellectual property rights in such
information first shall have been adequately protected, whether by foreign
filing of Patents or otherwise. In publications, each Party hereto shall
acknowledge appropriately the contribution of the other Party.

      6.2. SURVIVAL. The provisions of this Article VI shall survive until the
earlier of (i) expiration of the Option Term or (ii) the Effective Date (as
defined in the License Agreement) of the License Agreement, at which time the
terms of the License Agreement shall govern.

                                 PAGE 28 OF 54
<PAGE>

                                   ARTICLE VII

                                 INDEMNIFICATION

      7.1. INDEMNIFICATION BY HYBRIDON. Hybridon will indemnify, defend, and
hold Novartis and its Affiliates, their respective employees, shareholders,
officers, directors, and agents and consultants, and the successors, heirs and
assigns of each of them, harmless against any loss, damages, action, suit,
claim, demand, liability, expense, bodily injury, death or property damage
including reasonable attorney fees (a "Loss") that may arise from Third Party
claims brought, instituted or arising against such persons to the extent such
Loss is based on or arises out of the breach by Hybridon of any of its
covenants, representations or warranties set forth in this Agreement, but
excluding any such Loss that is caused by the negligent, willful or reckless
acts or omissions of Novartis.

      7.2. INDEMNIFICATION BY NOVARTIS. Novartis will indemnify, defend, and
hold Hybridon, and its Affiliates, and their respective employees, shareholders,
officers, directors, agents and consultants and the successors, heirs, and
assigns of each of them, harmless against any Loss that may arise from Third
Party claims brought, instituted or arising against such persons to the extent
such Loss is based on or arises out of (a) the breach by Novartis of any of its
covenants, representations or warranties set forth in this Agreement, but
excluding any such Loss that is caused by the negligent or reckless acts or
omissions of Hybridon or (b) the development, manufacture, use, storage or
handling of an IMO Candidate or IMO Lead by Novartis or its Affiliates or their
representatives, agents, licensees, sublicensees or subcontractors under this
Agreement, or any actual or alleged violation of law resulting therefrom,
including without limitation any death or bodily injury caused or allegedly
caused by the use of the IMO Candidate or IMO Lead, but excluding any such Loss
that is caused by the negligent, willful or reckless acts or omissions of
Hybridon.

      7.3. CLAIMS PROCEDURES. Each Person entitled to be indemnified by the
other Party (an "Indemnified Person") pursuant to Sections 7.1 or 7.2 hereof
shall give notice to the other Party (an "Indemnifying Party") promptly after
such Indemnified Person has actual knowledge of any threatened or asserted claim
as to which indemnity may be sought, and shall permit the Indemnifying Party to
assume the sole control of the defense of any such claim or any litigation
resulting therefrom; provided, however:

                                 PAGE 29 OF 54
<PAGE>

            (a)   that counsel for the Indemnifying Party, who shall conduct the
                  defense of such claim or any litigation resulting therefrom,
                  shall be approved by the Indemnified Person (whose approval
                  shall not unreasonably be withheld) and the Indemnified Person
                  may participate in such defense at such Party's expense
                  (unless: (i) the employment of counsel by such Indemnified
                  Person has been authorized by the Indemnifying Party; or (ii)
                  the Indemnified Person shall have reasonably concluded that
                  there may be a conflict of interest between the Indemnifying
                  Party and the Indemnified Person in the defense of such
                  action, in each of which cases the Indemnifying Party shall
                  pay the reasonable fees and expenses of one law firm serving
                  as counsel for all Indemnified Persons with respect to such
                  action, which law firm shall be subject to approval, not to be
                  unreasonably withheld, by the Indemnifying Party);

            (b)   the failure of any Indemnified Person to give notice as
                  provided herein shall not relieve the Indemnifying Party of
                  its obligations under this Agreement to the extent that the
                  failure to give notice did not result in harm to the
                  Indemnifying Party or materially compromise the defense of
                  such claim;

            (c)   no Indemnifying Party, in the defense of any such claim or
                  litigation, shall consent to entry of any judgment or enter
                  into any settlement, except with the approval of each
                  Indemnified Person (which approval shall not be unreasonably
                  withheld), except a settlement which imposes only a monetary
                  obligation on the Indemnifying Party and which includes as an
                  unconditional term thereof the giving of a release from all
                  liability in respect to such claim or litigation by the
                  claimant or plaintiff to the Indemnified Person;

            (d)   each Indemnified Person shall furnish such information or
                  reasonable assistance regarding itself or the claim in
                  question as an Indemnifying Party may reasonably request in
                  writing and shall be reasonably required in connection with
                  the defense of such claim and litigation resulting therefrom;
                  and

                                 PAGE 30 OF 54
<PAGE>

            (e)   no Indemnified Person shall settle or agree to a judgment with
                  respect to such claim or litigation without the consent of the
                  Indemnifying Party (which consent shall not be unreasonably
                  withheld).

      7.4. COMPLIANCE. The Parties shall comply fully with all applicable laws
and regulations in connection with their respective activities under this
Agreement, including but not limited to applicable rules concerning good
manufacturing practices according to the current EC / Pharmaceutical Inspection
Convention GMP guidelines, the U.S. Code of Federal Regulations, the laws and
regulations of the European Union and the corresponding applicable national laws
and regulations.

      7.5. SURVIVAL. The provisions of this Article VII shall survive expiration
or termination of this Agreement without limitation.

                                  ARTICLE VIII

                          INTELLECTUAL PROPERTY RIGHTS

      8.1. OWNERSHIP.

               8.1.1. Subject to any licenses explicitly granted under this
Agreement, each Party shall retain its intellectual property rights in all
Know-How and Patents Controlled by it on the Effective Date or developed or
acquired solely by it thereafter. For avoidance of any doubts, Novartis shall
retain ownership of all Novartis Intellectual Property, and Hybridon shall
retain ownership of all Hybridon Intellectual Property and Hybridon Background
Intellectual Property.

               8.1.2. During the Term of the Agreement, each of Hybridon and
Novartis will keep the other Party fully informed with respect to any new
intellectual property invented or generated by it or its Affiliates under this
Agreement.

            (a)   All intellectual property (including, without limitation,
                  data, discoveries, technical information, Know-how, Patents,
                  proprietary information, trade secrets and inventions)
                  invented or generated under this Agreement solely by one or
                  more persons obliged to assign their rights to Novartis or its
                  Affiliates during the Term shall be owned by Novartis and
                  shall be deemed

                                 PAGE 31 OF 54
<PAGE>

                  Novartis Patent Rights or Novartis Know-How as applicable;

            (b)   All intellectual property (including, without limitation,
                  data, discoveries, technical information, Know-how, Patents,
                  proprietary information, trade secrets and inventions)
                  invented or generated under this Agreement solely by one or
                  more persons obliged to assign their rights to Hybridon or its
                  Affiliates during the Term shall be owned by Hybridon and
                  shall be deemed Hybridon Patents or Hybridon Know-How, as
                  applicable;

            (c)   All intellectual property (including, without limitation,
                  data, discoveries, technical information, Know-how, Patents,
                  proprietary information, trade secrets and inventions)
                  invented or generated jointly under this Agreement by (i) one
                  or more persons obliged to assign their rights to Novartis or
                  its Affiliates and (ii) one or more persons obliged to assign
                  their rights to Hybridon or its Affiliates during the Term
                  shall be owned jointly by Novartis and Hybridon and shall be
                  Joint Intellectual Property and, subject to Section 4.1.1,
                  each Party shall have the right to use and exploit such Joint
                  Intellectual Property without any duty to account to the other
                  Party with respect to such use and exploitation. Each Party
                  will take all reasonable actions requested by the other Party,
                  including execution of appropriate patent filings and
                  applications for registration, to perfect the requesting
                  Party's ownership interest to the Joint Intellectual Property;
                  and

            (d)   Questions of inventorship under this Section 8.1.2 shall be
                  resolved in accordance with United States patent laws.

      8.2. PREPARATION AND COSTS. Hybridon shall take responsibility and pay for
the preparation, filing, prosecution and maintenance of all Hybridon Patents and
Patents that are part of the Hybridon Background Intellectual Property, and
Novartis shall take responsibility and pay for the preparation, filing,
prosecution and maintenance of all Novartis Patents and Joint Patents; provided
that, with respect to (a) Hybridon Patents and Patents that are part of the
Hybridon Background Intellectual Property that disclose or claim inventions
applicable solely to the IMO Candidates and IMO Leads and (b) Joint Patents that
disclose or claim inventions with

                                 PAGE 32 OF 54
<PAGE>

applicability beyond the IMO Candidates and IMO Leads, the Party having
responsibility for the preparation, filing, prosecution and maintenance of such
Hybridon Patents, Patents that are part of the Hybridon Background Intellectual
Property and Joint Patents shall promptly provide the other Party with copies of
all substantive communications from any patent office and with drafts of all
substantive filings to be made, reasonably in advance of their filing, with any
patent office with respect thereto; shall consider in good faith any comments
thereon provided by the other Party; and shall not unreasonably decline to
incorporate changes to such filing proposed by such other Party. Each Party
shall assist the other in the preparation and prosecution of such Patents and
shall execute all documents reasonably deemed necessary for the filing thereof
and/or for the vesting of title thereto as provided in this Agreement. Each
Party shall provide the JRC (or the other Party if the JRC no longer exists)
with periodic reports listing, by name, Hybridon Patents, Patents that are part
of the Hybridon Background Intellectual Property, Novartis Patents and Joint
Patents arising under the Research Program filed in the United States and other
jurisdictions, along with a general summary of the claims made and the
jurisdictions of filing. In good time, before the deadline for foreign filing of
any patent application filed in the United States, Hybridon will notify Novartis
whether it intends to foreign file such patent application, and if it intends to
do so, in what countries it proposes to foreign file.

      8.3. DISCONTINUATION. The Party initially responsible under Section 8.2
for the preparation, filing, prosecution and maintenance of a particular Patent
for an invention arising under the Research Program shall give at least [**]
advance notice to the other Party of any decision to cease preparation, filing,
prosecution or maintenance of that Patent. Discontinuation may be elected on a
country-by-country basis or for a Patent application or Patent series in total.
In such case, the other Party may elect, at its sole discretion, to continue
preparation, filing, and prosecution or maintenance of the discontinued Patent
at its sole expense.

      8.4. SURVIVAL. The provisions of this Article VIII shall survive
expiration or termination of this Agreement without limitation; provided that
the provisions of Section 8.3 as they relate to Patents that are solely owned by
either Party shall not survive expiration or termination of this Agreement.

                                 PAGE 33 OF 54
<PAGE>

                                   ARTICLE IX

                              TERM AND TERMINATION

      9.1. TERM. The term of this Agreement (the "Term") shall begin on the
Effective Date and expire upon expiration of the Option Term unless earlier
terminated by either Party hereto in accordance with this Agreement.

      9.2. TERMINATION.

               9.2.1. Upon ninety (90) days' written notice to Hybridon,
Novartis may, at its sole discretion, unilaterally terminate the Research
Program and this Agreement without cause.

               9.2.2. In the event that Hybridon shall breach any of its
material obligations under this Agreement or Novartis shall breach its
obligations under Section 3.2 hereof, and such breach shall not have been
remedied or steps initiated to remedy the same to the non-breaching Party's
reasonable satisfaction, within thirty (30) days after such non-breaching Party
sends written notice of such breach to the breaching Party, the non-breaching
Party may, at its sole discretion, unilaterally terminate the Research Program
and this Agreement without prejudice to its rights to seek damages in connection
with such breach.

               9.2.3. If at any time during the term of this Agreement, an Event
of Bankruptcy (as defined below) relating to a Party (the "Bankrupt Party")
occurs, the other Party shall have, in addition to all other legal and equitable
rights and remedies available hereunder, the option to terminate this Agreement
upon thirty (30) calendar days' written notice to the Bankrupt Party. As used
above, the term "Event of Bankruptcy" shall mean, with respect to a Party, (a)
the dissolution, termination of existence or liquidation of the Party; (b) the
institution of a bankruptcy action against the Party by a Third Party or the
appointment of a custodian or receiver with respect to all or substantially all
of the business or assets of the Party, which action, custodian or receiver is
not terminated or dismissed within ninety (90) calendar days following
institution or appointment; (c) the institution by the Party of any petition for
relief or similar proceeding or the making by the Party with respect to all or
substantially all of the business or assets of the Party of a composition or any
assignment or trust mortgage for the benefit of

                                 PAGE 34 OF 54
<PAGE>

creditors under any bankruptcy, reorganization, receivership or other similar
law affecting the rights of creditors generally; or (d) the insolvency of the
Party.

      9.3. EFFECT OF TERMINATION.

               9.3.1. In the event of any termination under Section 9.2.1
hereof, Novartis' obligation to perform any further work under the Research
Program shall cease as of the date of the termination notice, and Novartis shall
reimburse Hybridon for all Research Costs actually incurred by Hybridon prior to
the date of termination, regardless of whether such Research Costs become
payable subsequent to such date and shall pay Hybridon all amounts payable in
accordance with Section 3.1.3 for all periods prior to the date of termination,
provided that: (i) following the date of the termination notice, Hybridon shall
not initiate any additional internal activities or contract with any Third Party
for the provision of services or goods that will result in Hybridon incurring
Research Costs and shall use commercially reasonable efforts to minimize all
Research Costs previously incurred (including, without limitation, returning
materials to vendors where possible, winding down ongoing projects, reassigning
personnel to projects outside the Research Program, not initiating new
activities and refraining from hiring additional personnel to perform work on
the Research Program) and (ii) Hybridon shall provide Novartis with appropriate
documentation of such costs.

               9.3.2. Upon any termination of this Agreement by Novartis
pursuant to Section 9.2.1 or Hybridon pursuant to Sections 9.2.2 or 9.2.3: (i)
except with respect to any provision hereof that by its terms survives
termination and any payment obligation of Novartis that has accrued prior to the
date of termination, all rights and obligations of the Parties under this
Agreement shall terminate, (ii) all rights granted by Hybridon to Novartis
pursuant to the Novartis Research License shall revert to Hybridon, (iii) each
Party shall return to the other all Confidential Information of such other
Party, provided, however, that the Parties may each retain a copy of such other
Party's Confidential Information in segregated files solely for archival
purposes, and (iv) if the Commercialization Option has not already been
exercised, the Option Term shall terminate and the Commercialization Option
shall have no further force or effect.

               9.3.3. Upon any termination of this Agreement by Novartis
pursuant to Section 9.2.2 or Section 9.2.3, all rights granted to Novartis
hereunder shall survive (including,

                                 PAGE 35 OF 54
<PAGE>

without limitation, all rights granted by Hybridon to Novartis pursuant to the
Novartis Research License) and the License Agreement shall become effective
immediately, subject to payment by Novartis of the option exercise fee as set
forth in Section 5.1 of the License Agreement. In the event that Novartis fails
to make such payment, the License Agreement shall terminate and shall be of no
further force or effect, effective as of the day immediately following the day
on which such payment is ultimately due. Upon such termination, Novartis'
payment obligations pursuant to Sections 3.1 (with respect to Research Costs and
FTE costs incurred after the date of termination hereof) and 3.3.1 hereof shall
terminate, Novartis' payment obligations (whether arising before or after such
termination of this Agreement) under Section 3.3.2 shall survive for so long as
the License Agreement remains in effect, and all rights granted to Hybridon
hereunder shall terminate. Notwithstanding the foregoing, each Party's rights
and obligations pursuant to Article V with respect to confidentiality, Article
VII with respect to indemnification, and Article VIII with respect to
intellectual property rights shall survive any such termination in accordance
with their terms.

                                    ARTICLE X

                         REPRESENTATIONS AND WARRANTIES

      10.1. REPRESENTATIONS AND WARRANTIES OF HYBRIDON. Hybridon represents and
warrants to Novartis as follows:

               10.1.1. Authorization. This Agreement has been duly executed and
delivered by Hybridon and constitutes the valid and binding obligation of
Hybridon, enforceable against Hybridon in accordance with its terms except as
enforceability may be limited by fraudulent conveyance, insolvency, bankruptcy,
reorganization, moratorium and other laws relating to or affecting creditors'
rights generally and by general equitable principles. The execution, delivery
and performance of this Agreement have been duly authorized by all necessary
action on the part of Hybridon, its officers and directors. No provision of this
Agreement violates any other agreement that Hybridon may have with any other
person or company, and Hybridon acknowledges that Novartis has relied on that
representation in entering into this Agreement.

                                 PAGE 36 OF 54
<PAGE>

               10.1.2. Hybridon Controlled Rights. As of the Effective Date,
Hybridon owns or possesses adequate licenses or other rights to use all Hybridon
Intellectual Property and Hybridon Background Intellectual Property and to grant
the licenses and perform the obligations contemplated herein. The granting of
the Commercialization Option to Novartis hereunder does not violate any right
known to Hybridon of any Third Party.

               10.1.3. Third Party Patents. Except as disclosed in writing
between the Parties to this Agreement or their respective agents, as of the
Effective Date, to the best of Hybridon's knowledge, after reasonable inquiry,
there are no issued patents or pending patent applications that, if issued,
would be infringed by the exercise by Novartis of the rights granted herein or
the development, manufacture, use or sale of the IMO Leads pursuant to this
Agreement.

      10.2. REPRESENTATIONS AND WARRANTIES OF NOVARTIS. Novartis represents and
warrants to Hybridon that this Agreement has been duly executed and delivered by
Novartis and constitutes the valid and binding obligation of Novartis,
enforceable against Novartis in accordance with its terms except as
enforceability may be limited by fraudulent conveyance, insolvency, bankruptcy,
reorganization, moratorium and other laws relating to or affecting creditors'
rights generally and by general equitable principles. The execution, delivery
and performance of this Agreement have been duly authorized by all necessary
action on the part of Novartis, its officers and directors. No provision of this
Agreement violates any other agreement that Novartis may have with any other
person or company, and Novartis acknowledges that Hybridon has relied on that
representation in entering into this Agreement.

      10.3. LIMITATIONS.

               10.3.1. NO OTHER WARRANTIES. EXCEPT AS OTHERWISE EXPRESSLY SET
FORTH IN THIS AGREEMENT, ALL IMPLIED WARRANTIES, INCLUDING IMPLIED WARRANTIES OF
NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
EXCLUDED.

               10.3.2. CONSEQUENTIAL AND PUNITIVE DAMAGES. EXCEPT AS OTHERWISE
EXPRESSLY SET FORTH IN THIS AGREEMENT, NEITHER PARTY WILL BE LIABLE FOR
CONSEQUENTIAL, INCIDENTAL, MULTIPLE, SPECIAL OR PUNITIVE

                                 PAGE 37 OF 54
<PAGE>

DAMAGES OF ANY NATURE ARISING FROM SUCH PARTY'S ACTIVITIES UNDER THIS AGREEMENT;
PROVIDED, HOWEVER, THAT THIS LIMITATION SHALL NOT LIMIT THE INDEMNIFICATION
OBLIGATIONS OF THE PARTIES WITH RESPECT TO THIRD PARTY CLAIMS OR THE OBLIGATIONS
OF EITHER PARTY WITH RESPECT TO A BREACH OF ARTICLE IV OR ARTICLE V.

                                   ARTICLE XI

                            MISCELLANEOUS PROVISIONS

      11.1. GOVERNING LAW AND JURISDICTION. This Agreement shall be governed and
construed in accordance with the internal laws of the State of New York, United
States, and the Parties hereby submit to the exclusive jurisdiction of the
courts of New York.

      11.2. ADVERSE EVENTS. During the term of this Agreement, the Parties shall
keep each other promptly and fully informed and will promptly notify appropriate
authorities in accordance with applicable law, after receipt of information with
respect to any serious adverse event (as defined by the ICH Harmonized
Tripartite Guideline on Clinical Safety Data Management), directly or indirectly
attributable to the use or application of any IMO, and other material safety
information relating to any IMO. Each Party shall be entitled to disclose and
use all such information to regulatory authorities as required under applicable
law or regulation, to licensees, sublicensees and collaborators, under
obligations of confidentiality, for purposes relating to the research,
development and/or commercialization of products incorporating IMOs.

      11.3. DISPUTE RESOLUTION PROCESS FOR CRITICAL ISSUES. In the event of any
Critical Issue which the JRC is unable to resolve, the Parties shall refer the
matter to the President of Hybridon and the Head of the Novartis Respiratory
Disease Area of Novartis Institutes for BioMedical Research, who shall attempt
in good faith and using their best efforts to resolve the Critical Issue within
sixty (60) days of the date of initial referral of the matter from the JRC;
provided that, if such officers are unable to resolve such Critical Issue, the
provisions of Section 2.2.2 shall continue to apply.

                                 PAGE 38 OF 54
<PAGE>

      11.4. WAIVER. No provision of this Agreement may be waived except in
writing by both Parties hereto. No failure or delay by either Party hereto in
exercising any right or remedy hereunder or under applicable law will operate as
a waiver thereof, or a waiver of any right or remedy on any subsequent occasion.

      11.5. FORCE MAJEURE. Neither Party will be in breach hereof by reason of
its delay in the performance of or failure to perform any of its obligations
hereunder, if that delay or failure is caused by strikes, acts of God or the
public enemy, riots, incendiaries, interference by civil or military
authorities, compliance with governmental priorities for materials, or any cause
beyond its control without its fault or negligence.

      11.6. SEVERABILITY. Should one or more provisions of this Agreement be or
become invalid, then the Parties hereto shall attempt in good faith to agree
upon valid provisions in substitution for the invalid provisions, which in their
economic effect and other substance come so close to the invalid provisions that
it can be reasonably assumed that the Parties would have accepted this Agreement
with those new provisions. If the Parties are unable to agree on such valid
provisions, the invalidity of such one or more provisions of this Agreement
shall nevertheless not affect the validity of the Agreement as a whole, unless
the invalid provisions are of such essential importance for this Agreement that
it may be reasonably presumed that the Parties would not have entered into this
Agreement without the invalid provisions.

      11.7. GOVERNMENT ACTS. In the event that any act, regulation, directive,
or law of a country or its government, including its departments, agencies or
courts, should make impossible or prohibit, restrain, modify or limit any
material act or obligation of Novartis or Hybridon under this Agreement, the
Party, if any, not so affected, shall have the right, at its option, to suspend
or terminate this Agreement as to such country, if good faith negotiations
between the Parties to make such modifications therein as may be necessary to
fairly address the impact thereof, are not successful after a reasonable period
of time in producing mutually acceptable modifications to this Agreement.

      11.8. GOVERNMENT APPROVALS. Each Party will use commercially reasonable
efforts to obtain any government approval required to enable this Agreement to
become effective, or to enable any payment hereunder to be made, or any other
obligation hereunder to be observed or performed. Each Party will keep the other
informed of progress in obtaining any such

                                 PAGE 39 OF 54
<PAGE>

government approval, and will cooperate with the other Party in any such
efforts.

      11.9. ASSIGNMENT. This Agreement may not be assigned or otherwise
transferred by either Party without the prior written consent of the other
Party; provided, however, that Novartis may assign this Agreement without the
consent of Hybridon: (i) to any of its Affiliates, if Novartis guarantees to
full performance of such Affiliate's obligations hereunder; or (ii) in
connection with the transfer or sale of all or substantially all of its assets
or business to which this Agreement pertains, or a controlling interest in its
equity, or in the event of its merger or consolidation with another company. Any
purported assignment in contravention of this Section 11.9 shall, at the option
of the non-assigning Party, be null and void and of no effect. No assignment
shall release either Party from responsibility for the performance of any
accrued obligation of such Party hereunder. This Agreement shall be binding upon
and enforceable against the successor to or any permitted assignees of either of
the Parties.

      11.10. AFFILIATES. Each Party may perform its obligations hereunder
personally or through one or more Affiliates, although each Party shall
nonetheless be solely responsible for the performance of its Affiliates. Neither
Party shall permit any of its Affiliates to commit any act (including any act or
omission) which such Party is prohibited hereunder from committing directly.

      11.11. COUNTERPARTS. This Agreement may be executed in counterparts, each
of which shall be deemed to be original and all of which shall constitute one
and the same Agreement.

      11.12. NO AGENCY. Nothing herein contained shall be deemed to create an
agency, joint venture, amalgamation, partnership or similar relationship between
Novartis and Hybridon and/or their respective Affiliates. Notwithstanding any of
the other provisions of this Agreement, neither Party to this Agreement shall at
any time enter into, incur, or hold itself out to Third Parties as having
authority to enter into or incur, on behalf of the other Party, any commitment,
expense, or liability whatsoever, and all contracts, expenses and liabilities in
connection with or relating to the obligations of each Party under this
Agreement shall be made, paid, and undertaken exclusively by such Party on its
own behalf and not as an agent or representative of the other.

      11.13. NOTICE. All communications between the Parties with respect to any
of the

                                 PAGE 40 OF 54
<PAGE>

provisions of this Agreement will be sent to the addresses set out below, or to
such other addresses as may be designated by one Party to the other by notice
pursuant hereto, by (i) personal delivery (which shall be deemed received when
delivered), (ii) reputable international express courier (which shall be deemed
received when delivered), (iii) prepaid, certified mail (which shall be deemed
received by the other party on the seventh (7th) business day following deposit
in the mails), or (iv) facsimile transmission, or other electronic means of
communication (which shall be deemed received when transmitted), with
confirmation in the case of clause (iv) prepaid certified mail, given by the
close of business on or before the next following business day:

                  if to Novartis, at:

                        Novartis International Pharmaceutical Ltd.
                        Hurst Holme
                        12 Trott Road
                        Hamilton, HM 11
                        Bermuda
                        Attention: Emil Bock
                        Fax: [**]
                  with a copy to:

                        Novartis Institutes for BioMedical Research, Inc.
                        400 Technology Square
                        Cambridge, Massachusetts 02139
                        USA
                        Attention: Robert L. Thompson, Vice President and
                          General Counsel
                        Fax: [**]

                  and:

                        Novartis Horsham Research Centre
                        Wimblehurst Road
                        Horsham, West Sussex
                        RH12 5AB
                        United Kingdom
                        Attention: Head of  Novartis Respiratory Disease Area
                        Fax: [**]

      if to Hybridon, at:

                        Hybridon, Inc.
                        345 Vassar Street

                                 PAGE 41 OF 54
<PAGE>

                        Cambridge, Massachusetts 02139
                        USA
                        Attention: President
                        Fax: +(617) 679-5542

                  with a copy to:

                        Wilmer Cutler Pickering Hale and Dorr LLP
                        60 State Street
                        Boston, Massachusetts 02109
                        USA
                        Attention: David E. Redlick, Esq.
                        Fax: +(617) 526-5000

      11.14. HEADINGS. The paragraph headings are for convenience only and will
not be deemed to affect in any way the language of the provisions to which they
refer.

      11.15. AUTHORITY. The undersigned represent that they are authorized to
sign this Agreement on behalf of their respective Parties.

      11.16. ENTIRE AGREEMENT. This Agreement and the License Agreement contain
the entire understanding of the Parties relating to the matters referred to
herein and therein, supersede all prior agreements between the Parties with
respect to such matters (including without limitation the Confidential Term
Sheet dated January 26, 2005, the Material Transfer Agreement dated July 1, 2003
between Hybridon and Novartis Pharmaceuticals UK Limited, as amended prior to
the Effective Date, and the Mutual Confidentiality Agreements dated January 23,
2003 and June 8, 2004 between Hybridon and Novartis Pharmaceuticals UK Limited,
each as amended prior to the Effective Date, but excluding provisions of such
Material Transfer Agreement and Mutual Confidentiality Agreements relating to
restrictions on the use and disclosure of materials and information prior to the
Effective Date (it being understood that any material and information
transferred or disclosed between the Parties prior to the Effective Date
relating to the matters referred to in this Agreement and the License Agreement
will, after the Effective Date, be deemed to have been transferred or disclosed
under, and will be subject to the restrictions on use and disclosure set forth
in, this Agreement and the License Agreement)), and may only be amended by a
written document, duly executed on behalf of the respective Parties.

                            [SIGNATURE PAGE FOLLOWS]

                                 PAGE 42 OF 54
<PAGE>

      IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed
by their duly authorized representatives as of the date first written above.

                                      HYBRIDON, INC.

                                      By: /s/ Sudhir Agrawal
                                          --------------------------------------
                                      Name: Sudhir Agrawal
                                      Title: CEO/President

                                      NOVARTIS INTERNATIONAL PHARMACEUTICAL LTD.

                                      By: /s/ Emil Bock
                                          --------------------------------------
                                      Name: Emil Bock
                                      Title: Member of the Board of Directors

                                      By: /s/ Michael Jones
                                          --------------------------------------
                                      Name: Michael Jones
                                      Title: Member of the Board of Directors

                                 PAGE 43 OF 54
<PAGE>

                                  SCHEDULE 1.28
                                HYBRIDON PATENTS

                                HYBRIDON PATENTS

<TABLE>
<CAPTION>
                                                  STATUS
HYBN #   OTHER CASE #   APPLICATION NO.   TITLE   OF CASE   PATENT #   COUNTRY   FILING DATE   PUBLICATION #
------   ------------   ---------------   -----   -------   --------   -------   -----------   -------------
<S>      <C>            <C>               <C>     <C>       <C>        <C>       <C>           <C>
[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]        [**]      [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]
</TABLE>

<PAGE>

                                HYBRIDON PATENTS

<TABLE>
<CAPTION>
                                                  STATUS
HYBN #   OTHER CASE #   APPLICATION NO.   TITLE   OF CASE   PATENT #   COUNTRY   FILING DATE   PUBLICATION #
------   ------------   ---------------   -----   -------   --------   -------   -----------   -------------
<S>      <C>            <C>               <C>     <C>       <C>        <C>       <C>           <C>
[**]         [**]            [**]          [**]    [**]       [**]       [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]
</TABLE>

<PAGE>

                                HYBRIDON PATENTS

<TABLE>
<CAPTION>
                                                  STATUS
HYBN #   OTHER CASE #   APPLICATION NO.   TITLE   OF CASE   PATENT #   COUNTRY   FILING DATE   PUBLICATION #
------   ------------   ---------------   -----   -------   --------   -------   -----------   -------------
<S>      <C>            <C>               <C>     <C>       <C>        <C>       <C>           <C>
[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]
</TABLE>

<PAGE>

                                HYBRIDON PATENTS

<TABLE>
<CAPTION>
                                                  STATUS
HYBN #   OTHER CASE #   APPLICATION NO.   TITLE   OF CASE   PATENT #   COUNTRY   FILING DATE   PUBLICATION #
------   ------------   ---------------   -----   -------   --------   -------   -----------   -------------
<S>      <C>            <C>               <C>     <C>       <C>        <C>       <C>           <C>
[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]           [**]
</TABLE>

<PAGE>

                                HYBRIDON PATENTS

<TABLE>
<CAPTION>
                                                  STATUS
HYBN #   OTHER CASE #   APPLICATION NO.   TITLE   OF CASE   PATENT #   COUNTRY   FILING DATE   PUBLICATION #
------   ------------   ---------------   -----   -------   --------   -------   -----------   -------------
<S>      <C>            <C>               <C>     <C>       <C>        <C>       <C>           <C>
[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]

[**]         [**]            [**]          [**]    [**]                  [**]       [**]
</TABLE>

[**]

<PAGE>

HYBRIDON'S LOGO                                                          INVOICE

                                                               INVOICE DATE:
Street                                                         [MONTH][DAY] 200X
Town, Country
Phone and Fax Nr.                                              INVOICE NO.:XXXX

BILL TO:                                       FOR:
Novartis International Pharmaceutical Ltd.     Milestone for   200x
"Hurst Holme", 12 Trott Road                    event Y
Att. Mr. Emil Bock
P.O. Box HM 2899
Hamilton, HM LX
Bermuda

<TABLE>
<CAPTION>
                        DESCRIPTION                               AMOUNT (USD)
--------------------------------------------------------------   ---------------
<S>                                                              <C>
Milestone payment for event Y, according to paragraph XY
of agreement ZZZZ dated ......                                    US$ 000'000.00

Novartis Contract Code

Please specify the event for which the invoice is due, and add
any copies of invoices from third parties in case
reimbursement for third party work is agreed to

PLEASE REMIT BY WIRE TRANSFER WITHIN 60 DAYS TO:

        Receiving Bank - .......
        Swift Code - .......
        ABA Number - .......
        Credit Account - .......
        Beneficiary - .......
                                                                  --------------
                                                         TOTAL        000'000,00
                                                                  ==============
</TABLE>

If you have any questions concerning this invoice, contact ...
or e-mail to .....

VAT -Reg. No. Xxxxxxxxxx (if partner has one)

                BEST REGARDS,

<PAGE>

                                  SCHEDULE 1.40
                                  JOINT PATENTS

          [To be appended upon exercise of the commercialization option.]
<PAGE>

                                 SCHEDULE 2.2.1
                              INITIAL RESEARCH PLAN

             Acceptance Criteria for Hybridon IMO(TM)(TLR9 agonists)
           Criteria to be met to qualify candidate for CSP initiation

<TABLE>
<CAPTION>
            AREA                PARAMETER   ACCEPTANCE CRITERIA (FOR CSP)   RESPONSIBILITY FOR DATA
-----------------------------   ---------   -----------------------------   -----------------------
<S>                             <C>         <C>                             <C>
IN VITRO PHARMACOLOGY             [**]                 [**]                          [**]
                                  [**]                 [**]                          [**]
                                  [**]                 [**]                          [**]
IN VIVO PHARMACOLOGY              [**]                 [**]                          [**]
IN VITRO AND IN VIVO SAFETY       [**]                 [**]                          [**]
                                  [**]                 [**]                          [**]
                                  [**]                 [**]                          [**]
STRUCTURE AND PHYSICOCHEMICAL     [**]                 [**]                          [**]
PROPERTIES
                                  [**]                 [**]                          [**]
                                  [**]                 [**]                          [**]
                                  [**]                 [**]                          [**]
</TABLE>

<PAGE>

                                 SCHEDULE 2.3.2
                 EXAMPLES OF POSSIBLE CSP PHASE RESEARCH STUDIES

[**]

<PAGE>

HYBRIDON                            SCHEDULE 3.2
                             UPFRONT PAYMENT INVOICE             INVOICE

345 Vassar Street                                                INVOICE DATE:
Cambridge, Massachusetts 02139                                   JUNE 1, 2005
Tel. (617) 679-5517
Fax: (617) 679-5542
                                                                 INVOICE NO.: 1

BILL TO:                                     FOR:
                                             Research Collaboration Upfront
Novartis International Pharmaceutical Ltd.    payment
"Hurst Holme", 12 Trott Road
Att.: Mr. Emil Bock
P.O. Box HM 2899
Hamilton, HM LX
Bermuda

<TABLE>
<CAPTION>
                            DESCRIPTION                            AMOUNT (USD)
----------------------------------------------------------------   -------------
<S>                                                                <C>
Upfront payment pursuant to Section 3.2 of the Research            $4,000,000.00
Collaboration and Option Agreement dated May 31, 2005.

        PLEASE REMIT BY WIRE TRANSFER WITHIN 60 DAYS TO:
                Citibank
                ABA 021000089
                Bear Stearns
                A/C: 09253186
                For further credit to: Hybridon
                For further credit to account # 220-03084
                                                                   -------------
                                                           TOTAL   $4,000,000.00
                                                                   =============
</TABLE>

If you have any questions concerning this invoice, contact Bob Anderson at 617
-679-5517 or by e -mail at randersen@hybridon.com.

                        BEST REGARDS,
                        /s/ SUDHIR AGRAWAL
                        SUDHIR AGRAWAL

cc: Novartis Institutes for BioMedical Research (Attn.: Reto Wittwer)<PAGE>

                                                                  EXECUTION COPY

                                                                    Exhibit 10.2

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

                   LICENSE, DEVELOPMENT AND COMMERCIALIZATION

                                    AGREEMENT

                                 by and between

                                 HYBRIDON, INC.

                                       and

                   NOVARTIS INTERNATIONAL PHARMACEUTICAL LTD.

<PAGE>

                                                                  EXECUTION COPY

              LICENSE, DEVELOPMENT AND COMMERCIALIZATION AGREEMENT

      This License, Development and Commercialization Agreement (this "License
Agreement") is made this 31st day of May, 2005 by and between Hybridon, Inc.
("Hybridon"), a Delaware corporation with principal offices at 345 Vassar
Street, Cambridge, Massachusetts 02139 USA, and Novartis International
Pharmaceutical Ltd. ("Novartis"), a Bermuda corporation with principal offices
at Hurst Holme, 12 Trott Road, Hamilton, HM LX, Bermuda. Hybridon and Novartis
are sometimes referred to herein individually as a "Party" and together as the
"Parties." This License Agreement shall take effect on the Effective Date
pursuant to Section 2.1 hereof.

      Capitalized terms used but not defined in this License Agreement shall
have the meanings provided in the Research Collaboration and Option Agreement by
and between Hybridon and Novartis of even date herewith (the "Collaboration
Agreement").

                                  INTRODUCTION

      WHEREAS, pursuant to the Collaboration Agreement, the Parties are entering
into a collaboration with the objective of identifying and generating IMO Leads;
and

      WHEREAS, Novartis may exercise its Commercialization Option (as defined
herein) to license exclusively the Licensed IMOs (as defined herein) for
worldwide development and commercialization of Products (as defined herein) in
the Commercial Field of Use (as defined herein);

      NOW THEREFORE, in consideration of the foregoing premises, the Parties
agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

         1.1. "AAA" shall have the meaning set forth in Section 14.3.1 hereof.

         1.2. "ACCOUNTING STANDARDS" with respect to Hybridon shall mean that
Hybridon shall maintain records and books of accounts in accordance with United
States Generally

<PAGE>

Accepted Accounting Principles and with respect to Novartis shall mean that
Novartis shall maintain records and books of accounts in accordance with IFRS
(International Financial Reporting Standards).

         1.3. "ACQUISITION INTELLECTUAL PROPERTY" shall mean (a) Patents or
Know-How held or otherwise controlled by an Acquisition Affiliate immediately
prior to the Acquisition Event between Hybridon and such Acquisition Affiliate
(as defined in Section 1.4 below), other than Patents that do not specifically
relate to drug delivery or formulation technology held or otherwise controlled
by any such Acquisition Affiliate that would, but for a license granted
hereunder, be infringed by the development or commercialization of IMO
Candidates or IMO Leads and (b) Patents or Know-How developed or acquired and
controlled by an Acquisition Affiliate after the Acquisition Event between
Hybridon and such Acquisition Affiliate that specifically relate to drug
delivery or formulation technology, which Patents or Know-How are not developed
or acquired through the use of, or as an improvement to, any Hybridon
Intellectual Property or Hybridon Background Intellectual Property Controlled
(other than through an Acquisition Affiliate) by Hybridon.

         1.4. "ACQUISITION EVENT" shall mean any merger or other acquisition
between Hybridon and a Third Party occurring after the Effective Date and
pursuant to which such Third Party becomes an Affiliate of Hybridon, so long as
following such merger or acquisition Hybridon does not control and is not merged
with or into such Affiliate (an "Acquisition Affiliate").

         1.5. "ADDITIONAL INDICATION" shall have the meaning set forth in
Section 4.1 hereof.

         1.6. "AFFILIATE" means any Person who directly or indirectly controls
or is controlled by or is under common control with a Party. For purposes of
this definition, "control" or "controlled" means ownership directly or through
one or more Affiliates, of fifty percent (50%) or more of the shares of stock
entitled to vote for the election of directors, in the case of a corporation, or
fifty percent (50%) or more of the equity interest in the case of any other type
of legal entity, status as a general partner in any partnership, or any other
arrangement whereby a Party controls or has the right to control the Board of
Directors or equivalent governing body of

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 2 OF 53
<PAGE>

a corporation or other entity, or the ability to cause the direction of the
management or policies of a corporation or other entity. The Parties acknowledge
that in the case of certain entities organized under the laws of certain
countries outside of the United States, the maximum percentage ownership
permitted by law for a foreign investor may be less than fifty percent (50%),
and that in such case such lower percentage shall be substituted in the
preceding sentence; provided, that such foreign investor has the power to direct
the management and policies of such entity.

         1.7. "ARBITRATORS" shall have the meaning set forth in Section 14.3.1
hereof.

         1.8. "BANKRUPT PARTY" shall have the meaning set forth in Section 10.4
hereof.

         1.9. "CHEMICALLY MODIFY" OR "CHEMICAL MODIFICATION" shall mean the
modification of an IMO that [**], but specifically excluding [**].

         1.10. "COLLABORATION AGREEMENT" shall have the meaning set forth in the
preamble.

         1.11. "COMMERCIAL FIELD OF USE" shall mean prophylaxis, palliation,
diagnosis and treatment of the Initial Indications and Additional Indications
added pursuant to Article IV hereof by Products via any route of administration.

         1.12. "COMMERCIALIZATION OPTION" shall have the meaning set forth in
Section 4.2.1 of the Collaboration Agreement.

         1.13. "CONFIDENTIAL INFORMATION" shall have the meaning set forth in
Section 7.1 hereof.

         1.14. "CONTROLLED" shall mean, with respect to intellectual property,
the legal authority of a Party (either directly or through an Affiliate) to
grant the licenses or sublicenses of intellectual property rights as and to the
extent provided herein, or to otherwise disclose proprietary or trade secret
information as and to the extent provided herein, without breaching the terms of
any agreement with a Third Party, knowingly infringing upon the intellectual
property rights of a Third Party, or misappropriating the proprietary or trade
secret information of a Third Party.

         1.15. "COST OF GOODS SOLD" shall mean the total Product cost (standard
cost of

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 3 OF 53
<PAGE>

goods), variances, inventory re- / devaluation costs, non-Product-related
production costs, write-offs and Third Party royalties other than Section 5.6.2
royalties. The total Product cost is the total of material costs and processing
costs pertaining to the Products. Material costs relate to costs of devices used
to administer the Product, raw materials and intermediates needed for the
manufacturing process and costs of packaging material for these raw materials
and intermediates. Processing costs shall mean costs for direct labor, costs of
equipment, costs of production area overhead, costs of quality assurance, costs
of material handling overhead, costs of general factory overhead, costs for
utilities and costs for ecology. These costs are to be established on a regular,
standard basis. In this standard setting process all relevant costs as mentioned
above are determined. Costs of equipment shall be based on a planned utilization
of equipment. Idle capacity costs are not to be included in processing costs.
Costs of equipment are costs of depreciation or rent of the building
accommodating that equipment plus repair and maintenance for the building, and
costs for equipment depreciation, and other equipment costs such as costs for
repair and maintenance. The building costs shall be allocated to the equipment
using an appropriate key such as space occupied by the equipment. Production
area overhead costs are costs for personnel which typically embraces a
controlling and supervisory function, costs of indirect space such as costs for
a break room, costs of in-process control, costs of microbiological monitoring
of production environment, costs of training of process personnel, costs for
utilities and ecology, costs for auxiliary and consumables, costs of shop floor
control systems, costs for cleaning of production buildings, and costs of
working clothes. Quality assurance costs include costs of identifying and
analyzing the raw materials and intermediates needed for the manufacturing
process, costs of finished Product control, costs of production support, costs
of cleaning validation, costs of electronic data processing for the quality
assurance ("QA") / quality control ("QC") department, costs of microbiology
department, costs of laboratory infrastructure, costs of quality systems support
and compliance, costs of overheads within the QA/QC department. Materials
handling overhead costs are costs for warehousing and internal transportation of
raw material and semi-finished goods, costs of quality control of raw and
packaging material, costs of the purchasing department. General factory overhead
("GFO") costs shall mean costs of plant and production management, costs for
ensuring sufficient levels of safety, health and environment such as fire
brigade, medical services, documentation for transportation of hazardous goods.
Other GFO costs include costs for the scheduling of

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 4 OF 53
<PAGE>

production, costs of the maintenance of the bills of materials, costs for the
technical support, expenses of the plant administration and general services,
costs of information technology ("IT") for non-dedicated IT systems such as SAP.
Utility costs are costs associated with the consumption of supportive media such
as electricity, water, nitrogen, steam, and air. Ecology costs are costs
associated with the deposition of solid or liquid waste, purification of
effluent water, and purification of waste air. Variance costs attribute to the
following circumstance: Standard Cost of Goods include cost elements which are
set at so-called standard costs. They serve as a norm on how much typically a
Product costs. Deviations from such standard costs are captured in variances.
Inventory re- / devaluation shall mean the gain or loss as a result of the
inventory value adjustment due to changes in the standard costs. Non-
Product-related production costs shall contain Technical Operations Corporate
Headquarter overhead costs, non-Product-allocated QA costs, validation costs,
directly expensed IT project costs, and other costs that cannot be attributed to
specific Products. Write-offs are captured for the destruction of Products that
cannot be used anymore due to expiration of shelf-life, spoilage in the
production process, and transportation mishaps. Third Party royalties are
manufacturing- and/or supply royalties paid to Third Parties other than Section
5.6.2 royalties. Costs of Goods Sold shall be determined in accordance with
Novartis' usual and customary accounting methods, which are in accordance with
the Accounting Standards.

         1.16. "EFFECTIVE DATE" shall have the meaning set forth in Section 2.1
hereof.

         1.17. "EMEA" shall mean the European Medical Evaluation Agency, and any
successor agency serving the same function.

         1.18. "EPIGENESIS" shall mean EpiGenesis Pharmaceuticals, Inc.

         1.19. "EPIGENESIS AGREEMENT" shall mean that certain Development and
License Agreement, dated as of August 9, 2000, between Hybridon and EpiGenesis.

         1.20. "EUROPEAN MARKETING APPROVAL" shall mean Marketing Approval by
(i) the EMEA or (ii) the regulatory authorities in no fewer than three of the
Major Market Countries.

         1.21. "EVENT OF BANKRUPTCY" shall have the meaning set forth in Section
10.4 hereof.

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 5 OF 53
<PAGE>

         1.22. "EXCLUDED ANTISENSE IP" shall mean oligonucleotides or
oligonucleotide analogs or mimics thereof that (a) are targeted to a specific
sequence of RNA and (b) the primary mechanism of action of which is to hybridize
to such sequence of RNA and through such hybridization to modulate the
production of the targeted gene product, provided, that such oligonucleotides or
oligonucleotide analogs or mimics thereof [**] proprietary to Hybridon, [**].

         1.23. "FDA" shall mean the United States Food and Drug Administration,
and any successor agency serving the same function.

         1.24. "FIRST COMMERCIAL SALE" shall mean the first shipment of a
Product to a Third Party (other than to licensees or sublicensees for resale
rather than their own use) by Novartis or its Affiliate or sublicensee in a
country following applicable Regulatory Approval of the Product in such country
or, if no Regulatory Approval is required in a country, the first sale of the
Product in an arm's-length for-profit transaction to a Third Party (other than
to licensees or sublicensees for resale rather than their own use) by Novartis
or its Affiliate or sublicensee in such country.

         1.25. "FPFV" shall mean the first visit of the first patient or first
healthy human volunteer participating in a clinical trial with respect to a
Licensed IMO.

         1.26. "HYBRIDON BACKGROUND INTELLECTUAL PROPERTY" shall mean all
Patents and Know-How Controlled by Hybridon as of the Effective Date or at any
time during the term of this License Agreement that are necessary or useful for
the Parties or their Affiliates, contractors, agents or sublicensees to exploit
the licenses contemplated or to carry out the activities contemplated hereunder
and that are not otherwise Hybridon Intellectual Property or Joint Intellectual
Property. Notwithstanding the foregoing, "Hybridon Background Intellectual
Property" shall exclude any Acquisition Intellectual Property.

         1.27. "HYBRIDON INTELLECTUAL PROPERTY" shall mean Hybridon Know-How and
Hybridon Patent(s), but explicitly excluding Joint Intellectual Property and any
Acquisition Intellectual Property.

         1.28. "HYBRIDON KNOW-HOW" shall have the meaning set forth in Section
1.27 of the Collaboration Agreement.

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 6 OF 53
<PAGE>

         1.29. "HYBRIDON PATENTS" shall have the meaning set forth in Section
1.28 of the Collaboration Agreement. Upon Novartis' exercise of the
Commercialization Option, a list of Hybridon Patents shall be appended hereto as
Schedule 1.29, which will be updated periodically to reflect additions thereto
during the course of this License Agreement.

         1.30. "IMO" shall have the meaning set forth in Section 1.29 of the
Collaboration Agreement.

         1.31. "IMO CANDIDATE" shall have the meaning set forth in Section 1.30
of the Collaboration Agreement.

         1.32. "IMO LEAD" shall have the meaning set forth in Section 1.31 of
the Collaboration Agreement.

         1.33. "IMPROVEMENTS" shall have the meaning set forth in Section 1.32
of the Collaboration Agreement.

         1.34. "INDEMNIFYING PARTY" shall have the meaning set forth in Section
13.3 hereof.

         1.35. "INDEMNIFIED PERSON" shall have the meaning set forth in Section
13.3 hereof.

         1.36. "INITIAL INDICATIONS" shall mean all human allergic and/or
respiratory diseases, but specifically excluding oncology and infectious
diseases (other than cystic fibrosis, asthma and chronic obstructive pulmonary
disease pathologies, in each case resulting from infectious diseases) and
systemic autoimmune diseases.

         1.37. "JOINT INTELLECTUAL PROPERTY" shall mean Joint Know How and Joint
Patent(s).

         1.38. "JOINT KNOW-HOW" shall have the meaning set forth in Section 1.39
of the Collaboration Agreement.

         1.39. "JOINT PATENTS" shall have the meaning set forth in Section 1.40
of the Collaboration Agreement. Upon Novartis' exercise of the Commercialization
Option, a list of Joint Patents shall be appended hereto as Schedule 1.39, which
list will be updated periodically

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 7 OF 53
<PAGE>

to reflect additions thereto during the course of this License Agreement.

         1.40. "LICENSED IMOS" shall mean the IMO Candidates and IMO Leads.

         1.41. "LOSS" shall have the meaning set forth in Section 13.1 hereof.

         1.42. "MAJOR MARKET COUNTRIES" shall mean the United Kingdom, France,
Germany, Italy and Spain.

         1.43. "MARKETING APPROVAL" shall mean the final Regulatory Approval
that ultimately enables Novartis, its Affiliates or sublicensees, directly or
through intermediaries, to sell a Product commercially to the ultimate consumer
in a particular country.

         1.44. "MHLW" shall mean the Japanese Ministry of Health, Labor and
Welfare, and any successor agency serving the same function.

         1.45. "NET SALES" shall mean, with respect to any Product, the gross
amount invoiced by or on behalf of Novartis or its Affiliates or sublicensees
for that Product sold to Third Parties (other than to licensees or sublicensees
for resale rather than their own use) in bona fide, arm's-length transactions,
less the following deductions, determined in accordance with Novartis' standard
accounting methods as generally and consistently applied by Novartis and its
Affiliates in determining net product sales, to the extent included in the gross
invoiced sales price of any Product or otherwise directly paid or incurred by
Novartis, its Affiliates, or sublicensees with respect to the sale of such
Product:

                  (a) Normal and customary trade and quantity discounts actually
         allowed and properly taken directly with respect to sales of the
         Product;

                  (b) Amounts repaid or credited by reason of defects, rejection
         recalls, returns, rebates and allowances of goods, or because of
         retroactive price reductions specifically identifiable to the Product;

                  (c) Chargebacks and other amounts paid on the sale or
         dispensing of such Product;

                  (d) Amounts payable resulting from governmental (or agency
         thereof) mandated rebate programs;

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 8 OF 53
<PAGE>

                  (e) Tariffs, duties, excise, sales, value-added, and other
         taxes (other than taxes based on income);

                  (f) Retroactive price reductions that are actually allowed or
         granted;

                  (g) Cash discounts for timely payment;

                  (h) Delayed ship order credits;

                  (i) Discounts pursuant to indigent patient programs and
         patient discount programs, including, without limitation, "Together Rx"
         and coupon discounts;

                  (j) All freight, postage and insurance included in the invoice
         price;

                  (k) Uncollectible amounts on previously sold Products that are
         written off for financial reporting purposes (provided that if any such
         amounts are subsequently collected, such amounts shall be included in
         Net Sales upon such collection);

                  (l) [**] percent ([**]%) for distribution and warehousing
         expenses; and

                  (m) Any other specifically identifiable amounts included in
         the gross invoice of the Product that should be credited for reasons
         substantially equivalent to those listed above;

      all as determined in accordance with Novartis' usual and customary
      accounting methods, which are in accordance with the Accounting Standards.
      Sales from Novartis to its Affiliates and sublicensees shall be
      disregarded for the purpose of calculating Net Sales. Any of the items set
      forth above that would otherwise be deducted from the invoice price in the
      calculation of Net Sales but which are separately charged to Third Parties
      (other than licensees or sublicensees) shall not be deducted from the
      invoice price in the calculation of Net Sales.

      Furthermore:

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 9 OF 53
<PAGE>

                  (i) In the case of any sale or other disposal of a Product
         between or among Novartis and its Affiliates, licensees and
         sublicensees for resale, Net Sales shall be calculated as above only on
         the value charged or invoiced on the first arm's-length sale thereafter
         to a Third Party (other than licensees or sublicensees);

                  (ii) In the case of any sale which is not invoiced or is
         delivered before invoice, Net Sales shall be calculated at the time of
         shipment or when the Product is paid for, if paid for before shipment
         or invoice;

                  (iii) In the case of any sale or other disposal for value,
         such as barter or countertrade, of any Product, or part thereof, other
         than in an arm's-length transaction exclusively for money, Net Sales
         shall be calculated as above on the value of the non-cash consideration
         received or the fair market price (if higher) of the Product in the
         country of sale or disposal; and

                  (iv) In the event that the Product is sold in a finished
         dosage form containing the Licensed IMO in combination with one or more
         other active ingredients (a "Combination Product"), the Net Sales of
         the Product, for the purpose of determining royalty payments, shall be
         determined by multiplying the Net Sales (as defined above in this
         Section) of the Combination Product by the fraction A/(A+B), where A is
         the weighted (by sales volume) average sales price in a particular
         country of the Product when sold separately in finished form and B is
         the weighted average sales price in that country of the other
         product(s) sold separately in finished form. In the event that such
         average sales price cannot be determined for both the Product and the
         other product(s) in the combination, Net Sales for purposes of
         determining royalty payments shall be agreed by the Parties based on
         the relative value contributed by each component, and such agreement
         shall not be unreasonably withheld.

         1.46. "NON-SECTION 5.2 PRODUCTS" shall have the meaning set forth in
Section 5.3.2 hereof.

         1.47. "NON-VALID CLAIM COUNTRY" shall mean a country in which no Valid
Claim with respect to the applicable Hybridon Patent, Patent that is part of the
Hybridon Background

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 10 OF 53
<PAGE>

Intellectual Property, or Joint Patent in which Hybridon retains an interest has
existed during the term of this License Agreement.

         1.48. "PATENTS" shall mean all existing patents and patent applications
and all patent applications hereafter filed, including any continuation,
continuation-in-part, divisional, provisional or any substitute applications,
any patent issued with respect to any such patent applications, any reissue,
reexamination, renewal or extension (including any supplementary protection
certificate) of any such patent, and any confirmation patent or registration
patent or patent of addition based on any such patent, and all foreign
counterparts of any of the foregoing.

         1.49. "PERSON" shall mean, any individual, corporation, partnership,
association, joint-stock company, trust, unincorporated organization or
government or political subdivision thereof.

         1.50. "PHASE IIB CLINICAL TRIAL" shall mean a human clinical trial, the
principal purpose of which is to allow selection of the particular doses to be
applied in a Phase III Clinical Trial.

         1.51. "PHASE III CLINICAL TRIAL" shall mean a human clinical trial, the
principal purpose of which is to establish safety and efficacy of one or more
particular doses in patients being studied, and which will (or are intended to)
satisfy the requirements of a pivotal trial for purposes of preparing and
submitting a filing for Regulatory Approval in a particular country.

         1.52. "PRODUCT" shall mean a pharmaceutical product including,
conjugated to, or comprised of, a Licensed IMO with or without other active
ingredients in finished dosage form, ready for administration to the ultimate
consumer, and any Improvements thereto.

         1.53. "PROVIDING PARTY" shall have the meaning set forth in Section 7.1
hereof.

         1.54. "RECEIVING PARTY" shall have the meaning set forth in Section
7.1.1 hereof.

         1.55. "REGULATORY APPROVAL" shall mean all authorizations by the
appropriate governmental entity or entities necessary for commercial sale of a
Product in a particular country including, without limitation and where legally
necessary prior to commercial sale, approval of labeling, price, reimbursement
and manufacturing.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 11 OF 53
<PAGE>

         1.56. "RESEARCH FIELD OF USE" shall have the meaning set forth in
Section 1.60 of the Collaboration Agreement.

         1.57. "SALES REPORT" shall mean a written report or reports showing
each of: (a) the Net Sales of each Product in each country in the world during
the reporting period by Novartis and each Affiliate and sublicensee; (b) the
royalties, payable in United States Dollars, which shall have accrued under
Section 5.5 hereof in respect of such Net Sales and the basis of calculating
those royalties; (c) withholding taxes, if any, required by law to be deducted
in respect of any such Net Sales; and (d) dispositions of the Products other
than pursuant to sale for cash.

         1.58. "SECTION 5.2 PRODUCTS" shall have the meaning set forth in
Section 5.2 hereof.

         1.59. "SECTION 10.3 DISPUTE" shall have the meaning set forth in
Section 14.3 hereof.

         1.60. "THIRD PARTY" shall mean any Person that is not a Party or an
Affiliate of either Party.

         1.61. "VALID CLAIM" shall mean a claim of any issued, unexpired
Hybridon Patent or Joint Patent in which Hybridon retains an interest that shall
not have been withdrawn, canceled or disclaimed, nor held invalid or
unenforceable by a governmental authority or a court of competent jurisdiction
in an unappealed or unappealable decision, and which has not been admitted to be
invalid or unenforceable through reissue, disclaimer or otherwise.

         1.62. "VALID CLAIM COUNTRY" shall mean, with respect to a Product, a
country in which a Valid Claim with respect to the applicable Hybridon Patent or
Joint Patent in which Hybridon retains an interest has existed during the term
of this License Agreement.

                                   ARTICLE II

                       EFFECTIVENESS; RIGHTS AND LICENSES

         2.1. EFFECTIVENESS. Subject to Section 12.3 hereof, this License
Agreement (other than this Section 2.1, which shall become effective upon
execution by the Parties of this

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 12 OF 53
<PAGE>

License Agreement) shall become effective on the date on which Hybridon is
deemed to have received the Commercialization Exercise Notice from Novartis
pursuant to Section 4.2.2 of the Collaboration Agreement or in connection with
termination of the Collaboration Agreement as set forth in Section 9.3.3 thereof
(the "Effective Date").

         2.2. NOVARTIS RIGHTS; LIMITATIONS.

            2.2.1. Subject to the other provisions of this License Agreement,
Hybridon grants to Novartis and its Affiliates a worldwide, exclusive license
(with the right to sublicense) for the term, subject only to Hybridon's retained
right to perform its obligations under the Collaboration Agreement so long as
such Collaboration Agreement is still in effect and subject to the rights
granted by Hybridon to EpiGenesis under the EpiGenesis Agreement, under the
Hybridon Intellectual Property and Hybridon's interest in the Joint Intellectual
Property, to: (i) make, have made, use, have used, research, have researched,
develop, have developed, commercialize, have commercialized, manufacture, have
manufactured, promote, have promoted, sell, have sold, distribute, have
distributed, market, have marketed, import, have imported, export and have
exported, the Licensed IMOs and Products in the Commercial Field of Use and (ii)
research, have researched, develop and have developed Licensed IMOs in the
Research Field of Use.

            2.2.2. Subject to the other provisions of this License Agreement,
Hybridon grants to Novartis and its Affiliates a worldwide, non-exclusive
license (with the right to sublicense) for the term under the Hybridon
Background Intellectual Property to (i) to make, have made, use, have used,
research, have researched, develop, have developed, commercialize, have
commercialized, manufacture, have manufactured, promote, have promoted, sell,
have sold, distribute, have distributed, market, have marketed, import, have
imported, export and have exported, the Licensed IMOs and Products in the
Commercial Field of Use and (ii) research, have researched, develop and have
developed Licensed IMOs in the Research Field of Use.

            2.2.3. Notwithstanding the foregoing and subject to Section 4.2
hereof, nothing herein shall give Novartis or its Affiliates the right to, and
Novartis shall not (and shall not permit its Affiliates to): (i) Chemically
Modify any Licensed IMO or use the Hybridon Intellectual Property to create any
immunomodulatory oligonucleotide that is the same or

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 13 OF 53
<PAGE>

substantially structurally equivalent to any Licensed IMO or that is covered by
any claims in the Hybridon Patents; or (ii) conduct any clinical trial designed
to support an indication outside the Commercial Field of Use without Hybridon's
consent.

            2.2.4. Any sublicense granted by Novartis pursuant to this License
Agreement must be granted pursuant to a written agreement that subjects the
sublicensee to not less than the relevant restrictions, limitations and
obligations in this License Agreement. Novartis shall remain primarily
responsible for all of its obligations under this License Agreement and shall
take prompt action to enforce its rights against its sublicensees should any
such sublicensee breach its obligation to comply with the restrictions,
limitations or obligations set forth in this License Agreement. Novartis shall
designate Hybridon as a third party beneficiary if Hybridon is damaged as a
result of any breach by a sublicensee of any relevant restriction, limitation,
or obligation pertaining to this License Agreement.

         2.3. IMMUNITY FROM SUIT. In the event that the exercise by Novartis
and/or its Affiliates or sublicensees of the licenses and rights granted
pursuant to this License Agreement would infringe during the term of this
License Agreement a claim of an issued Patent Controlled by Hybridon, which
Patent is not otherwise covered by the grant in Section 2.2 or any Acquisition
Intellectual Property, Hybridon hereby grants to Novartis and its Affiliates or
sublicensees a worldwide, non-exclusive, royalty-free license and immunity from
suit by Hybridon and its Affiliates under such issued Patent for Novartis, its
Affiliates and or sublicensees to discover, research, develop, make, use,
import, export, distribute, market, promote, offer for sale, and sell the
Licensed IMOs and the Products in the Commercial Field of Use.

         2.4. TECHNOLOGY NECESSARY TO THE LICENSE. If Hybridon conceives and
reduces to practice during the term of this License Agreement any new technology
relating to a Licensed IMO or Product and such new technology is necessary to
Novartis' exercise of its licensed rights pursuant to this License Agreement,
which technology is not otherwise covered by the grant in Section 2.2, then
Hybridon hereby grants to Novartis and its Affiliates and sublicensees a
worldwide, non-exclusive, royalty-free license under such new technology to
discover and have discovered, research and have researched, develop and have
developed, make and have made, use and have used, import and have imported,
export and have exported, distribute and have

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 14 OF 53
<PAGE>

distributed, market and have marketed, promote and have promoted, offer for sale
and have offered for sale, sell and have sold such new technology in connection
with the Licensed IMO or the Product in the Commercial Field of Use.

                                   ARTICLE III

                        DEVELOPMENT AND COMMERCIALIZATION

         3.1. DEVELOPMENT AND COMMERCIALIZATION RIGHTS. The rights granted to
Novartis pursuant to Section 2.2 are exclusive to Novartis, even as to Hybridon,
subject to Hybridon's right to perform its obligations under the Collaboration
Agreement and subject to 35 USC Sections 200-212, 37 CFR Section 401 et seq. and
related governmental implementing regulations, as applicable.

         3.2. TRADEMARK AND TRADENAME RIGHTS. Novartis, its Affiliates and
sublicensees shall be entitled, in their sole discretion, to select the
trademarks and tradenames for all Products, which trademarks and tradenames for
any Product may vary by country or within a country, in Novartis' sole
discretion. Novartis shall own all right, title and interest in and to such
trademarks and tradenames, and Hybridon shall have no rights with respect to any
such trademarks and tradenames.

         3.3. INFORMATION TRANSFER. Within sixty (60) days after the Effective
Date, Hybridon shall promptly deliver to Novartis all information (including,
without limitation, Know-How) of Hybridon and its Affiliates that is necessary
or useful, or is reasonably requested by Novartis, for further development,
manufacture and commercial exploitation and distribution of a Licensed IMO or
Product subject to any confidentiality obligations owed by Hybridon to Third
Parties. Subject to the foregoing, such information (including, without
limitation, Know-How) shall include a summary of all material written
communications between Hybridon or its other licensees and the FDA concerning
the Licensed IMO or Product and shall also include copies of all Patents,
copyrights, copyright registrations and applications therefor and all other
manifestations of the intellectual property related to the Licensed IMO or
Product of Hybridon or its Affiliates, whether in human or machine readable
form, and, if commercially and technically reasonable, in an electronic form
compatible with Novartis' systems; provided that Novartis shall only reimburse
Hybridon's costs of providing data in a form compatible with its systems so long

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 15 OF 53
<PAGE>

as Hybridon has provided Novartis with a reasonably detailed description of such
costs and obtained Novartis' prior written approval to incur such costs.
Novartis shall reimburse such pre-approved costs actually incurred by Hybridon
within [**] days after receipt by Novartis of Hybridon's Invoice for the same.

         3.4. REGULATORY APPROVALS. Novartis, its Affiliates and sublicensees
will be responsible for all required Regulatory Approvals. All filings will be
made by Novartis, its Affiliates or sublicensees. All Regulatory Approvals will
be held in the name of Novartis, its Affiliates or sublicensees. Novartis, its
Affiliates or sublicensees shall have the right to, and Hybridon shall provide
the requisite notification to regulatory authorities to, cross reference any
relevant information such as but not limited to any clinical and pre-clinical
files and regulatory filings, such as but not limited to Drug Master Files of
Hybridon and its Affiliates, with respect to Licensed IMOs and Products, for the
purpose of regulatory filings hereunder.

         3.5. DEVELOPMENT AND COMMERCIALIZATION EFFORTS. Novartis shall use
commercially reasonable efforts, similar to those used by Novartis or its
Affiliates in the research, development and commercialization of other products
of Novartis or its Affiliates that are of similar commercial potential and at a
similar stage of development, to develop and commercialize Products hereunder.

                                   ARTICLE IV

                          ADDITIONAL INDICATION OPTION

         4.1. ADDITIONAL INDICATION OPTION. Subject to Section 4.2 hereof,
Novartis shall have the option (each, an "Additional Indication Option") to
include one or more additional indications (each, an "Additional Indication") in
the Commercial Field of Use. Notwithstanding the foregoing, Novartis shall not
have the right to expand the Commercial Field of Use to include oncology
indications, non-human indications, or infectious disease indications not
originally included in the Commercial Field of Use.

         4.2. EXERCISE OF AN ADDITIONAL INDICATION OPTION. If Novartis generates
pre-clinical data that supports the inclusion of Additional Indication(s) in the
Commercial Field of Use, Novartis may notify Hybridon that it wishes to include
such Additional Indication(s) in

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 16 OF 53
<PAGE>

the Commercial Field of Use at any time after the second anniversary of the
Effective Date of the Collaboration Agreement (the "Option Notice"). Novartis
shall provide Hybridon with a summary of the pre-clinical data that supports the
inclusion of the Additional Indication(s), which Hybridon may use only in
connection with its review of Novartis' exercise of the Additional Indication
Option. Hybridon may not withhold its consent to the expansion of the Commercial
Field of Use to include such Additional Indication(s) unless, as of the date on
which Hybridon receives such Option Notice, Hybridon: (a) has granted exclusive
rights to such Additional Indication(s) to a Third Party; (b) is actively
negotiating with a Third Party to grant such rights; or (c) has [**] such
Additional Indication(s) in which the first visit of the first patient has
occurred. If Hybridon withholds its consent to the requested expansion for the
reasons set forth above, Hybridon shall use good faith efforts to obtain for
Novartis the agreement of such Third Party to negotiate a co-commercialization
agreement with Novartis with respect to such Additional Indication(s). If
Hybridon withholds its consent to the requested expansion because, as of the
date on which Hybridon receives the Option Notice, Hybridon is actively
negotiating with a Third Party to grant exclusive rights to the Additional
Indication(s), but Hybridon does not grant such rights to such Third Party
within [**] after the receipt of the Option Notice, Hybridon shall agree to the
expansion of the Commercial Field of Use to include such Additional
Indication(s). Novartis may submit multiple Option Notices during the term of
this License Agreement; provided that Novartis may not submit an Option Notice
covering Additional Indication(s) that are closely related to any Additional
Indication(s) for which Novartis has submitted an Option Notice during the
previous [**] period. Upon the successful exercise of an Additional Indication
Option, the term "Commercial Field of Use" shall be deemed to include the
Additional Indication(s) covered by such exercise.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 17 OF 53
<PAGE>

                                    ARTICLE V

                         MILESTONE AND ROYALTY PAYMENTS

         5.1. OPTION EXERCISE FEE. Upon this License Agreement taking effect in
accordance with Section 2.1 hereof and following delivery of the certificate set
forth in Section 12.3 hereof and subject to the terms thereof, Novartis shall
pay to Hybridon the sum of [**] U.S. Dollars (US$[**]) in accordance with
Section 14.1 (Invoice Requirement).

         5.2. MILESTONE PAYMENTS WITH RESPECT TO PRODUCTS FOR INITIAL
INDICATIONS. Novartis shall notify Hybridon within thirty (30) business days
after the occurrence of a milestone event for which payment is due pursuant to
this Section 5.2. Each milestone payment set forth below shall be paid by
Novartis to Hybridon with respect only to the first [**] Products originally
developed for Initial Indications to achieve the related milestone ("Section 5.2
Products"). Notwithstanding the foregoing, achievement of a milestone by
[**]Products that have the same active ingredient shall only trigger separate
payments of the related milestone payment if such Products [**][**] that are
separately approved by the FDA, the EMEA (or not less than [**] of the
regulatory authorities of the Major Market Countries), or the MHLW, as
applicable. Each milestone payment shall be paid in accordance with Section 14.1
(Invoice Requirement) following notice by Novartis that the applicable milestone
has been met. The Parties agree that, if only one (1) Product is in either Phase
IIb Clinical Trials or Phase III Clinical Trials at a particular time and
Novartis, in its sole discretion, ceases development of such Product, then each
milestone payment which has previously been paid for such Product pursuant to
this Section 5.2 shall be credited as a milestone payment for the next Product
developed for any Initial Indication(s). For clarity, the milestone payments set
out in the following table shall be payable only once for each Product (and its
related substituted Product if the original Product was abandoned) and shall be
payable no more than an aggregate of [**] times as to all Products developed for
Initial Indication(s) (even if there are more than [**] Products developed for
Initial Indications). The Parties agree further that each of the [**] milestones
in the table below shall be deemed to have occurred (and, if not made
previously, the related milestone payment shall become payable) upon the
occurrence of any subsequent milestone in the table below with respect to the
same Product. Novartis may deduct from any milestone payments otherwise due to
Hybridon under this Section 5.2 the amount of any

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 18 OF 53
<PAGE>

withholding and similar taxes required under applicable United States law to be
withheld from such payments and paid to United States tax authorities.

<TABLE>
<CAPTION>
MILESTONE       PAYMENT
---------       -------
<S>             <C>
   [**]         US$[**]
   [**]         US$[**]
   [**]         US$[**]
   [**]         US$[**]
   [**]         US$[**]
</TABLE>

         5.3. MILESTONE PAYMENTS WITH RESPECT TO PRODUCTS FOR ADDITIONAL
INDICATIONS. Novartis shall notify Hybridon within thirty (30) business days
after the occurrence of a milestone event for which payment is due pursuant to
this Section 5.3. Novartis shall pay to Hybridon milestone payments as set forth
below with respect to certain Products developed for Additional Indications in
accordance with Section 14.1 (Invoice Requirement). Novartis may deduct from any
milestone payments otherwise due to Hybridon under this Section 5.3 the amount
of any withholding and similar taxes required under applicable United States law
to be withheld from such payments and paid to United States tax authorities.

            5.3.1. Products for Which Milestones Are Payable Under Section 5.2.
Novartis shall make the milestone payments set forth in the following table with
respect to Section 5.2 Products that are later developed for Additional
Indications. For clarity, if a Section 5.2 Product is developed for an
Additional Indication, the achievement of each milestone set forth below with
respect to the Additional Indication shall trigger payment of the related
milestone payment regardless of whether the comparable payment has already been
paid with respect to the Initial Indication. Notwithstanding the foregoing,
achievement of milestones by [**] Products that have the same active ingredient
shall only trigger separate payment of the related milestone payment if such
Products have distinct formulations and distinct labels that are separately
approved by the FDA, the EMEA (or not less than [**] of the regulatory
authorities of the Major Market Countries), or the MHLW, as applicable. The
Parties agree that, if Novartis, in its sole

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 19 OF 53
<PAGE>

discretion, ceases development of a Section 5.2 Product, then all milestone
payments which have previously been paid for such Product pursuant to this
Section 5.3.1 shall be credited as milestone payments for the next Section 5.2
Product or non-Section 5.2 Product developed for the same Additional Indication.
For clarity, the milestone payments set out in the following table shall be
payable only once for each Section 5.2 Product and its related substituted
Section 5.2 Product or non-Section 5.2 Product developed for the same Additional
Indication, if the original Section 5.2 Product was abandoned.

<TABLE>
<CAPTION>
MILESTONE       PAYMENT
---------       -------
<S>             <C>
  [**]          US$[**]
  [**]          US$[**]
  [**]          US$[**]
</TABLE>

            5.3.2. Products for Which Milestones Are Not Payable Under Section
5.2. Novartis shall make the milestone payments set forth in the following table
with respect to Products, other than Section 5.2 Products, that are developed
for Additional Indications ("non-Section 5.2 Products"). Notwithstanding the
foregoing, achievement of milestones by [**] non-Section 5.2 Products that have
the same active ingredient shall only trigger separate payment of the related
milestone payment if such non-Section 5.2 Products have distinct formulations
and distinct labels that are separately approved by the FDA, the EMEA (or not
less than [**] of the regulatory authorities of the Major Market Countries), or
the MHLW, as applicable. The Parties agree that, if Novartis, in its sole
discretion, ceases development of a non-Section 5.2 Product, then all milestone
payments which have previously been paid for such non-Section 5.2 Product
pursuant to this Section 5.3.2 shall be credited as milestone payments for the
next Section 5.2 Product or non-Section 5.2 Product developed for the same
Additional Indication. For clarity, the milestone payments set out in the
following table shall be payable only once for each abandoned non-Section 5.2
Product and its related substituted Section 5.2 Product or non-Section 5.2
Product. The Parties agree further that, in the event that, for a particular
non-Section 5.2 Product, the "Initiation of Phase III Clinical Trial" milestone
is achieved prior to the achievement of the "Initiation of Phase IIb Clinical
Trial" milestone for the same Product, then at

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 20 OF 53
<PAGE>

such time as the "Initiation of Phase III Clinical Trial" milestone is achieved,
the milestone payments for both milestones shall become payable.

<TABLE>
<CAPTION>
MILESTONE         PAYMENT
---------         -------
<S>               <C>
  [**]            US$[**]
  [**]            US$[**]
  [**]            US$[**]
  [**]            US$[**]
  [**]            US$[**]
</TABLE>

         5.4. MILESTONE PAYMENT FOR $[**] IN NET SALES. For each of the first
[**] Products for which worldwide Net Sales in a calendar year exceeds [**] U.S.
Dollars (US$[**]), Novartis shall pay to Hybridon the sum of [**] U.S. Dollars
(US$[**]) in accordance with Section 14.1 (Invoice Requirement) upon the first
achievement of such milestone by each such Product. Notwithstanding the
foregoing, achievement of the milestone by [**] Products that have the same
active ingredient shall only trigger separate payment of the milestone payment
if such Products have distinct formulations and distinct labels that are both
approved by any of the FDA, the EMEA (or not less than [**] of the regulatory
authorities of the Major Market Countries), or the MHLW.

         5.5. ROYALTY PAYMENTS. Novartis shall make the following royalty
payments to Hybridon on Net Sales of all Products on an aggregate, cumulative,
basis in accordance with Section 6.1 hereof.

<TABLE>
<CAPTION>
                   CUMULATIVE WORLDWIDE NET SALES                   ROYALTY IN VALID     ROYALTY IN NON-VALID
                FOR ALL PRODUCTS ON A COMBINED BASIS                 CLAIM COUNTRY          CLAIM COUNTRY
------------------------------------------------------------------  ----------------     --------------------
<S>                                                                 <C>                  <C>
On Net Sales less than US$[**]                                           [**]%                  [**]%

On the increment of Net Sales greater than or equal to US$[**] but
less than US[**]                                                         [**]%                  [**]%

On the increment of Net Sales greater than or equal to US$[**]           [**]%                  [**]%
</TABLE>

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 21 OF 53
<PAGE>

For purposes of the second and third columns of the above table, the
determination of whether particular Net Sales are subject to the royalty rate
for Valid Claim Countries or the royalty rate for Non-Valid Claim Countries
shall be made on a country-by-country and Product-by-Product basis.

         5.6. REDUCED MILESTONE AND ROYALTY OBLIGATIONS. The obligation of
Novartis, its Affiliates and sublicensees to pay milestones and royalties to
Hybridon under this License Agreement shall be reduced upon the occurrence of
the following events:

            5.6.1. In the event that Novartis terminates this License Agreement
in accordance with Section 10.3, the rights of Novartis, its Affiliates and
sublicensees under this License Agreement shall remain unaffected, but its
milestone and post-termination royalty payment obligations shall be reduced by
[**] percent ([**]%).

            5.6.2. In the event that Novartis, its Affiliates or sublicensees is
required to pay Third Party royalties, milestones or license fees in order to
use a Licensed IMO or the Hybridon Intellectual Property or Hybridon Background
Intellectual Property as contemplated hereunder, Novartis' obligation to pay
royalties to Hybridon with respect to any Product(s) incorporating such Licensed
IMO shall be reduced dollar for dollar on par with the amounts actually paid by
Novartis, its Affiliate or sublicensee to such Third Party; provided that
Novartis' milestone and royalty payment obligations pursuant to this License
Agreement shall not be reduced by more than [**] percent ([**]%) of the amount
that would otherwise be due from Novartis to Hybridon;

            5.6.3. Notwithstanding the foregoing and the provisions of Section
5.7, Novartis' royalty obligations for any Product shall not in any case be
reduced below [**] percent ([**]%) with respect to Net Sales in Valid Claim
Countries or [**] percent ([**]%) with respect to Net Sales in Non-Valid Claim
Countries.

         5.7. COST OF GOODS SOLD ADJUSTMENT. For each Product, in any calendar
quarter that the Cost of Goods Sold for such Product, expressed as a percentage
of Net Sales, exceeds [**] percent ([**]%) on an aggregated, worldwide basis,
then the royalty amounts payable by Novartis to Hybridon pursuant to Section 5.5
with respect to sales of such Product during such calendar quarter shall be
reduced by one-third, subject to the minimum royalties set forth in

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 22 OF 53
<PAGE>

Section 5.6.3. Such reduced royalty rates shall remain in effect with respect to
any given Product so long as Cost of Goods Sold continues to exceed [**] percent
([**]%) of Net Sales for such Product on an aggregated, worldwide basis. In the
event that worldwide Cost of Goods Sold ceases to exceed [**] percent ([**]%) of
Net Sales for such Product on an aggregated, worldwide basis, such reduction
shall cease to apply unless and until Cost of Goods Sold again exceeds [**]
percent ([**]%) of Net Sales as set forth herein. Novartis shall determine
worldwide Cost of Goods Sold on a calendar quarterly basis, and, if Cost of
Goods Sold exceeds [**] percent ([**]%) of Net Sales on an aggregated, worldwide
basis, Novartis shall include Cost of Goods in its Sales Reports pursuant to
Section 6.1.

                                   ARTICLE VI

                              REPORTING OBLIGATIONS

         6.1. QUARTERLY ROYALTY OBLIGATIONS. Within forty-five (45) days after
the close of each calendar quarter (each such calendar quarter being sometimes
referred to herein as a "reporting period") during the term of this License
Agreement following the First Commercial Sale of a Product, Novartis shall
furnish to Hybridon a Sales Report for Hybridon's review. Upon receipt of a
Sales Report, Hybridon shall submit an invoice to Novartis substantially in the
form of Exhibit A hereto for all undisputed royalty amounts due from Novartis.
Novartis shall pay such royalty amounts within thirty (30) days after receipt of
the invoice.

         6.2. AUDITS. Novartis shall keep, and shall cause its Affiliates and
sublicensees to keep, complete and accurate records of Net Sales relating to
Sales Reports and payments required under Article V. Hybridon will have the
right, at its own expense, except as specified below, to have an independent,
certified public accountant, selected by it and reasonably acceptable to
Novartis, review any such records of Novartis, its Affiliates and sublicensees
in the location(s) where such records are maintained by Novartis, its Affiliates
and sublicensees upon reasonable notice and during regular business hours and
under obligations of confidence, for the sole purpose of verifying the basis and
accuracy of payments made under Article V within the prior thirty-six (36) month
period. Notwithstanding the foregoing, Hybridon shall not be entitled to: (i)
conduct any audit pursuant to this

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 23 OF 53
<PAGE>

Section 6.2 more frequently than once per year and (ii) review any records it
has previously reviewed in connection with an audit pursuant to this Section 6.2
unless Novartis is required or elects to restate its accounts relating to such
records. If the review of such records reveals that Novartis has failed to
accurately report information pursuant to Section 6.1, then Novartis shall
promptly pay to Hybridon any corresponding unpaid amounts due under Article V
(together with interest at the rate of one percent (1%) per annum). If any such
underpayment is greater than five percent (5%) of the amount actually due for
any calendar year, Novartis shall pay all of the costs of such review.

         6.3. EXCHANGE RATES. With respect to amounts invoiced in United States
Dollars, all such amounts shall be expressed in United States Dollars. With
respect to amounts invoiced in a currency other than United States Dollars, all
such amounts shall be expressed both in the currency in which the amount was
invoiced and in the United States Dollar equivalent. The United States Dollar
equivalent shall be calculated using Novartis' then-current standard exchange
rate methodology applied in its external reporting (for the purpose of clarity,
this is ultimately based on official rates such as Reuters and the European
Central Bank) for the conversion of foreign currency sales into United States
Dollars.

         6.4. CURRENCY OF ROYALTY PAYMENTS. All royalty payments due under this
License Agreement shall be paid in United States Dollars.

                                   ARTICLE VII

                                 CONFIDENTIALITY

         7.1. UNDERTAKING. Each Party shall keep confidential, and, other than
as provided herein, shall not use or disclose, directly or indirectly, any trade
secrets, confidential or proprietary information, or any other knowledge,
information, documents or materials, owned, developed or possessed by the other
Party (the "Providing Party"), whether in tangible or intangible form, the
confidentiality of which such other Party takes reasonable measures to protect
(collectively, "Confidential Information"). The Parties hereby agree that, for
the purposes of this License Agreement, discussion between the Parties, if any,
regarding Novartis' plans for developing and commercializing Licensed IMOs and
Products will be deemed to be the confidential information of Novartis.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 24 OF 53
<PAGE>

            7.1.1. A Party receiving Confidential Information (the "Receiving
Party") shall use commercially reasonable efforts not less than those efforts
such Receiving Party uses to protect its own proprietary information to prevent
the unauthorized use and disclosure of such information of the Providing Party
and to prevent unauthorized persons or entities from obtaining or using such
information.

            7.1.2. The Receiving Party further agrees to refrain from directly
or indirectly taking any action which would constitute or facilitate the
unauthorized use or disclosure of Confidential Information. The Receiving Party
may disclose Confidential Information to its Affiliates, officers, employees and
agents, to authorized licensees and sublicensees, and to subcontractors in
connection with the identification, generation, development and manufacture of
Licensed IMOs, as applicable, to the extent necessary to enable such parties to
perform their obligations hereunder or under the applicable license, sublicense
or subcontract, as the case may be; provided, however, that such Affiliates,
officers, employees, agents, licensees, sublicensees and subcontractors have
entered into confidentiality agreements for secrecy and non-use of such
Confidential Information offering no less than the protection afforded hereby
which by their terms shall be enforceable by injunctive relief at the instance
of the Providing Party.

            7.1.3. The Receiving Party shall be liable for any unauthorized use
and disclosure of such information by its Affiliates, officers, employees and
agents and any such sublicensees and subcontractors.

         7.2. EXCEPTIONS.

            7.2.1. Non-Confidential Information. Notwithstanding the foregoing,
the provisions of Section 7.1 hereof shall not apply to Confidential Information
that the Receiving Party can establish by clear and convincing evidence:

                  (a) have entered the public domain without such Receiving
         Party's breach of any obligation owed to the Providing Party;

                  (b) are or have become known to the Receiving Party from a
         source other than the Providing Party, other than by breach of an
         obligation of confidentiality owed to the Providing Party; or

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 25 OF 53
<PAGE>

                  (c) are independently developed by the Receiving Party without
         reference to or reliance upon knowledge, information, documents or
         materials of the Providing Party and without breach of this License
         Agreement.

            7.2.2. Other Exceptions. In addition, a Receiving Party may,
notwithstanding the obligations of Section 7.1, disclose Confidential
Information:

                  (a) that the Receiving Party can establish by clear and
         convincing evidence is permitted to be disclosed by the prior written
         consent of the Providing Party;

                  (b) that the Receiving Party can establish by clear and
         convincing evidence is required to be disclosed by the Receiving Party
         to defend litigation or to comply with applicable laws or regulations
         (including without limitation disclosure obligations under applicable
         securities laws or the regulations of any stock exchange or NASDAQ), or
         in connection with filings with the FDA, the United States Patent and
         Trademark Office or other similar governmental agencies, provided that
         the Receiving Party provides prior written notice of such disclosure to
         the Providing Party and takes reasonable and lawful actions to avoid or
         minimize the degree of such disclosure; or

                  (c) concerning the existence and terms of this License
         Agreement and the status of transactions described herein, under
         obligations of confidentiality, to the Receiving Party's existing and
         potential advisors, investors that are bona fide venture capital or
         institutional investors that make such investments for the potential
         financial return and not for strategic purposes (so long as such
         investor does not have more than $1 billion in world-wide
         pharmaceutical revenue in the most recently completed calendar year)
         and any Person considering to acquire Hybridon or a controlling
         interest in Hybridon (a "Potential Acquirer"). Notwithstanding the
         foregoing, Hybridon shall not make any such disclosure to any Potential
         Acquirer (i) until discussions with such Potential Acquirer progress to
         a stage at which the Potential Acquirer is engaged in comprehensive due
         diligence of Hybridon's business and Hybridon has a good faith belief
         that the consummation of the proposed acquisition

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 26 OF 53
<PAGE>

         has become reasonably likely to occur and (ii) unless the Potential
         Acquirer has entered into a confidentiality agreement at least as
         strict as the provisions of this Section 7.2.2(c), designating Novartis
         as a third party beneficiary and prohibiting the Potential Acquirer
         from disclosing or using for its own purposes (other than evaluation of
         the proposed transaction with Hybridon) any such information. Hybridon
         shall notify Novartis in writing prior to any disclosure pursuant to
         this Section 7.2.2(c), but shall not be required to disclose the
         identity of any Potential Acquirer until after consummation or
         abandonment of the transaction, at which time Hybridon shall provide
         Novartis with a copy of the confidentiality agreement executed by such
         Potential Acquirer.

         7.3. PUBLICITY. The Parties will agree upon the timing and content of
any initial press release or other public communications relating to this
License Agreement and the transactions contemplated herein.

            7.3.1. Except as set forth in Section 7.3.2 or to the extent already
disclosed in that initial press release or other public communication, no public
announcement concerning the existence or the terms of this License Agreement or
the transactions described herein shall be made, either directly or indirectly,
by Hybridon or Novartis, except as may be legally required by applicable laws,
regulations, or judicial order, without first obtaining the approval of the
other Party and agreement upon the nature, text, and timing of such
announcement.

            7.3.2. Subject to this Article VII, a Party may issue press releases
or make public communications or otherwise make disclosures that such Party
determines to be necessary to comply with applicable law (including disclosure
requirements of the U.S. Securities and Exchange Commission, NASDAQ or any stock
exchange on which securities issued by such Party are traded); provided that
such Party shall provide the other Party with a copy of the proposed text of
such press releases, public communications or disclosure in advance of the
scheduled release or publication thereof to afford such other Party a reasonable
opportunity to review and comment upon the proposed text.

            7.3.3. The Party desiring to make any such public announcement shall
provide the other Party with a written copy of the proposed announcement in
sufficient time (no less than

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 27 OF 53
<PAGE>

thirty (30) days or such shorter period as may be required to enable a Party to
comply with applicable law) prior to public release to allow such other Party to
comment upon such announcement, prior to public release.

         7.4. SURVIVAL. The provisions of this Article VII shall survive for
five (5) years after the expiration or termination of this License Agreement.

                                  ARTICLE VIII

                                   PUBLICATION

         8.1. PUBLICATION. Hybridon and its Affiliates agree not to publish or
publicly present any results, data, or scientific findings with respect to the
Research Program (except in connection with filings with the FDA, the United
States Patent and Trademark Office or other similar governmental entities in
other countries or regions) without the prior written consent of Novartis. In
publications authorized by Novartis pursuant hereto, each Party hereto shall
acknowledge appropriately the contribution of the other Party.

         8.2. SURVIVAL. The provisions of this Article VIII shall survive until
expiration of this License Agreement.

                                   ARTICLE IX

                          INTELLECTUAL PROPERTY RIGHTS

         9.1. OWNERSHIP.

            9.1.1. Subject to any licenses explicitly granted under this License
Agreement, each Party shall retain its intellectual property rights in all
Know-How and Patents Controlled by it on the Effective Date or developed or
acquired solely by it thereafter. For avoidance of any doubts, Novartis shall
retain ownership of all Novartis Intellectual Property, and Hybridon shall
retain ownership of all Hybridon Intellectual Property and Hybridon Background
Intellectual Property.

            9.1.2. During the term of this License Agreement, each of Hybridon
and Novartis will keep the other Party fully informed with respect to any new
intellectual property invented or generated by it or its Affiliates under this
License Agreement.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 28 OF 53
<PAGE>

                  (a) All intellectual property (including, without limitation,
         data, discoveries, technical information, Know-how, Patents,
         proprietary information, trade secrets and inventions) invented or
         generated under this License Agreement solely by one or more persons
         obliged to assign their rights to Novartis or its Affiliates during the
         term of this License Agreement shall be owned by Novartis;

                  (b) All intellectual property (including, without limitation,
         data, discoveries, technical information, Know-how, Patents,
         proprietary information, trade secrets and inventions) invented or
         generated under this License Agreement solely by one or more persons
         obliged to assign their rights to Hybridon or its Affiliates during the
         term of this License Agreement shall be owned by Hybridon and shall be
         deemed Hybridon Patents or Hybridon Know-How, as applicable;

                  (c) All intellectual property (including, without limitation,
         data, discoveries, technical information, Know-how, Patents,
         proprietary information, trade secrets and inventions) invented or
         generated jointly under this License Agreement by (i) one or more
         persons obliged to assign their rights to Novartis or its Affiliates
         and (ii) one or more persons obliged to assign their rights to Hybridon
         or its Affiliates during the term of this License Agreement shall be
         owned jointly by Novartis and Hybridon and shall be Joint Intellectual
         Property and, subject to Section 2.2.1, each Party shall have the right
         to use and exploit such Joint Intellectual Property without any duty to
         account to the other Party with respect to such use and exploitation.
         Each Party will take all reasonable actions requested by the other
         Party, including execution of appropriate patent filings and
         applications for registration, to perfect the requesting Party's
         ownership interest to the Joint Intellectual Property; and

                  (d) Questions of inventorship under this Section 9.1.2 shall
         be resolved in accordance with United States patent laws.

         9.2. PREPARATION AND COSTS. Hybridon shall take responsibility and pay
for the preparation, filing, prosecution and maintenance of all Hybridon Patents
and Patents that are part of the Hybridon Background Intellectual Property, and
Novartis shall take responsibility and pay for the preparation, filing,
prosecution and maintenance of all Novartis Patents and Joint Patents;

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 29 OF 53
<PAGE>

provided that, with respect to (a) Hybridon Patents and Patents that are part of
the Hybridon Background Intellectual Property that disclose or claim inventions
applicable solely to the Licensed IMOs and (b) Joint Patents that disclose or
claim inventions with applicability beyond the Licensed IMOs, the Party having
responsibility for the preparation, filing, prosecution and maintenance of such
Hybridon Patents, Patents that are part of the Hybridon Background Intellectual
Property and Joint Patents shall promptly provide the other Party with copies of
all substantive communications from any patent office and with drafts of all
substantive filings to be made, reasonably in advance of their filing, with any
patent office with respect thereto; shall consider in good faith any comments
thereon provided by the other Party; and shall not unreasonably decline to
incorporate changes to such filing proposed by such other Party. Each Party
shall assist the other in the preparation and prosecution of such Patents and
shall execute all documents reasonably deemed necessary for the filing thereof
and/or for the vesting of title thereto as provided in this License Agreement.
In good time, before the deadline for foreign filing of any patent application
filed in the United States, Hybridon will notify Novartis whether it intends to
foreign file such patent application, and if it intends to do so, in what
countries it proposes to foreign file.

         9.3. DISCONTINUATION. The Party initially responsible under Section 9.2
for the preparation, filing, prosecution and maintenance of a particular Patent
for an invention arising under the Research Program shall give at least thirty
(30) days advance notice to the other Party of any decision to cease
preparation, filing, prosecution or maintenance of that Patent. Discontinuation
may be elected on a country-by-country basis or for a Patent application or
Patent series in total. In such case, the other Party may elect, at its sole
discretion, to continue preparation, filing, and prosecution or maintenance of
the discontinued Patent at its sole expense.

         9.4. THIRD PARTY INFRINGEMENT.

            9.4.1. If either Party becomes aware of any activity that such Party
believes represents an infringement of the claims of the Hybridon Patents,
Patents that are part of the Hybridon Background Intellectual Property or Joint
Patents with respect to a Licensed IMO or Product, the Party obtaining such
knowledge shall advise the other of all relevant facts and circumstances
pertaining to the potential infringement as soon as practicable.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 30 OF 53
<PAGE>

            9.4.2. Novartis shall have the first right, but no obligation, to
initiate and prosecute such legal proceedings, at its own expense and in the
name of Novartis, and to control the defense of any declaratory judgment action,
if the infringing party is making, having made, using or selling a product, or
proposing to do so, that is or may be competitive with the Licensed IMO or
Product; provided, however, that no settlement shall be entered into by Novartis
without the written consent (which consent shall not be unreasonably withheld)
of Hybridon if such settlement would materially affect Hybridon's interests
(including without limitation the validity or enforceability of any Hybridon
Patent or Patent that is part of the Hybridon Background Intellectual Property).
Hybridon shall reasonably cooperate with Novartis in such effort, including,
without limitation, being joined as a party to such action, and Novartis shall
reimburse Hybridon for the out-of-pocket costs and expenses incurred by Hybridon
in so cooperating with Novartis. In deciding whether to pursue, and in the
pursuit of such legal proceedings, Novartis will use diligent, commercially
reasonable efforts consistent with those used by Novartis for its own compounds
or products of similar commercial potential.

            9.4.3. If Novartis does not succeed, within ninety (90) days after
receiving notice from Hybridon of the potential infringement or within sixty
(60) days after providing Hybridon with notice of such potential infringement,
either in terminating such infringement or in instituting an action to prevent
continuation thereof, or if Novartis notifies Hybridon that Novartis does not
plan to seek to terminate the infringement or to institute any such action, then
Hybridon shall have the right to do so at its own cost and expense. In such
case, Novartis shall reasonably cooperate with Hybridon in such effort,
including being joined as a party to such action, if necessary, and Hybridon
shall reimburse Novartis for the out-of-pocket costs and expenses incurred by
Novartis in so cooperating with Hybridon.

            9.4.4. The costs and expenses (including attorneys' fees) of any
action against an infringement brought in accordance with this Section 9.4, or
to defend a declaratory judgment suit as provided in this Section 9.4, shall be
borne by the Party controlling the infringement or declaratory judgment action.

            9.4.5. Any monetary recovery obtained in legal proceedings brought
against an infringer pursuant to Section 9.4.2 or 9.4.3, whether obtained by
settlement, judgment or otherwise, shall first be applied to reimburse the
Parties for the costs (including reasonable

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 31 OF 53
<PAGE>

attorneys' fees) that each incurred in connection with such legal action. If the
monetary recovery is insufficient to fully reimburse both parties for all such
costs, both parties shall receive the same percentage of their respective costs.
The value of any monetary recovery remaining once both Parties have been
reimbursed for all of their costs shall be treated as Net Sales and subject to
earned royalties as set forth in Article V hereof.

            9.4.6. Notwithstanding anything in this Section 9.4 to the contrary,
Hybridon may participate, through its own counsel and at its own cost and
expense, in any proceeding involving a challenge to the validity or
enforceability of any Hybridon Patent, Patent that is part of the Hybridon
Background Intellectual Property or Joint Patent that relates to both a Licensed
IMO and to IMO(s) that are not subject to the licenses granted to Novartis
hereunder.

         9.5. NOTIFICATION, DEFENSE AND SETTLEMENT OF THIRD PARTY CLAIMS.

            9.5.1. Hybridon shall promptly notify Novartis in the event Hybridon
becomes aware of the existence of any Third Party Patent that may be infringed
by the making, having made, using, having used, developing, having developed,
commercializing, having commercialized, manufacturing, having manufactured,
promoting, having promoted, selling, having sold, distributing, having
distributed, marketing, having marketed, importing, having imported, exporting
or having exported of a Licensed IMO or Product.

            9.5.2. If a Third Party asserts that a Patent owned by it is
infringed by the making, having made, using, having used, developing, having
developed, commercializing, having commercialized, manufacturing, having
manufactured, promoting, having promoted, selling, having sold, distributing,
having distributed, marketing, having marketed, importing, having imported,
exporting or having exported of a Licensed IMO or Product, Novartis shall,
subject to Section 5.6.2, defend and be solely responsible for defending,
against any such assertions and controlling any related litigation at its own
cost and expense. Hybridon shall reasonably cooperate with Novartis in such
effort, including, without limitation, being joined as a party to such action,
if necessary, and Novartis shall reimburse Hybridon for the out-of-pocket costs
and expenses incurred by Hybridon in so cooperating with Novartis.

            9.5.3. Notwithstanding anything in this Section 9.5 to the contrary,
Hybridon may participate, at its own cost and expense, in any proceeding
involving a challenge to the

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 32 OF 53
<PAGE>

validity or enforceability of any Hybridon Patent, Patent that is part of the
Hybridon Background Intellectual Property or Joint Patent that relates to both a
Licensed IMO and to IMO(s) that are not subject to the licenses granted to
Novartis hereunder.

         9.6. PIRATE GOODS. Novartis and its Affiliates shall exercise
commercially reasonable efforts to monitor sales and take action to prevent
trade in goods by a Third Party that violate Novartis' or its Affiliates'
exclusive legal rights to market, price and sell a Product in such a market. In
the event that Hybridon first becomes aware of such a trade in goods by a Third
Party which violates Novartis' or its Affiliates' exclusive legal rights,
Hybridon shall notify Novartis within seven (7) calendar days of first becoming
aware of such trading by a Third Party.

         9.7. DRUG PRICE COMPETITION AND PATENT TERM RESTORATION ACT AND
PEDIATRIC EXCLUSIVITY.

            9.7.1. The Parties shall cooperate in an effort to avoid the loss of
any rights which may otherwise be available to the Parties under the provisions
of the Drug Price Competition and Patent Term Restoration Act of 1984 or
comparable laws outside of the United States and for pediatric exclusivity, and
Novartis shall reimburse Hybridon in accordance with Section 14.1 (Invoice
Requirement) for reasonable out-of-pocket costs and expenses incurred by
Hybridon in so cooperating with Novartis.

            9.7.2. Hybridon shall provide any relevant information related to
Patents included in the Hybridon Intellectual Property, Hybridon Background
Intellectual Property or Joint Intellectual Property to Novartis or its
Affiliates such that Novartis or its Affiliates, as an NDA applicant, may
provide accurate and complete information to the FDA or other applicable
regulatory authorities.

                                    ARTICLE X

                              TERM AND TERMINATION

         10.1. TERM. The term of this License Agreement shall extend with
respect to each Product in each Valid Claim Country until the expiration of the
last to expire of a Valid Claim

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 33 OF 53
<PAGE>

included in the Hybridon Patents or Joint Patents covering the Product in such
country. In the case of a Non-Valid Claim Country, the term of this License
Agreement shall extend with respect to each Product in each such country until
the earlier of (a) the date that is ten (10) years after the date of the First
Commercial Sale of the Product in such country or (b) the last day in any
calendar year during which Novartis has lost market exclusivity with respect to
such Product in such country. For purposes of this License Agreement, Novartis
shall be deemed to have lost market exclusivity with respect to a Product in a
particular country if annual Net Sales of such Product in such country have
decreased by [**] percent ([**]%) from Net Sales in the previous calendar year.
Once market exclusivity has been lost with respect to a Product in a particular
country, Novartis' obligations to pay royalties hereunder shall expire with
respect to such Product in such country. For each country, upon expiration of
Novartis' obligation to pay royalties hereunder with respect to a Product, the
licenses granted to Novartis in Section 2.2 shall convert to fully paid-up,
royalty-free, perpetual licenses with respect to such Product, which licenses
shall survive any expiration or termination of this Agreement.

         10.2. TERMINATION BY NOVARTIS WITHOUT CAUSE. Upon sixty (60) days'
written notice to Hybridon, Novartis may, at its sole discretion, unilaterally
terminate this License Agreement on a Product-by-Product and/or
country-by-country basis without cause.

         10.3. MATERIAL BREACH. In the event either Party shall be in material
breach of its obligations hereunder, the other Party may give written notice to
the breaching Party specifying the claimed particulars of such breach, and, in
the event such material breach is not cured, or effective steps to cure such
material breach have not been initiated or are not thereafter diligently pursued
within ninety (90) days following the date of such written notification, in
addition to any other damages or remedies available to the non-breaching Party,
the non-breaching Party shall have the right thereafter to terminate this
License Agreement by giving not less than thirty (30) days prior written notice
to the breaching Party to such effect. If the breaching Party disputes the basis
for such termination, the breaching Party may institute an arbitration
proceeding pursuant to Section 14.3 by notifying the other Party of such dispute
as set forth in Section 14.3.1 prior to the effective date of termination as set
forth in the immediately preceding sentence, and, in such event, the
non-breaching Party shall not be entitled to terminate this License Agreement
pursuant to this Section 10.3 unless and until the Arbitrators issue an order
pursuant to Section 14.3

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 34 OF 53
<PAGE>

declaring that a material breach has occurred and all opportunities for appeal
of such order have been exhausted.

         10.4. BANKRUPTCY. If at any time during the term of this License
Agreement, an Event of Bankruptcy (as defined below) relating to a Party (the
"Bankrupt Party") occurs, the other Party shall have, in addition to all other
legal and equitable rights and remedies available hereunder, the option to
terminate this License Agreement upon thirty (30) calendar days' written notice
to the Bankrupt Party. As used above, the term "Event of Bankruptcy" shall mean,
with respect to a Party, (a) the dissolution, termination of existence or
liquidation of the Party; (b) the institution of a bankruptcy action against the
Party by a Third Party or the appointment of a custodian or receiver with
respect to all or substantially all of the business or assets of the Party,
which action, custodian or receiver is not terminated or dismissed within ninety
(90) calendar days following institution or appointment; (c) the institution by
the Party of any petition for relief or similar proceeding or the making by the
Party with respect to all or substantially all of the business or assets of the
Party of a composition or any assignment or trust mortgage for the benefit of
creditors under any bankruptcy, reorganization, receivership or other similar
law affecting the rights of creditors generally; or (d) the insolvency of the
Party.

         10.5. EFFECT OF TERMINATION.

            10.5.1. Upon termination of this License Agreement by Novartis
pursuant to Section 10.2 with respect to all Products and all countries covered
by this License Agreement or by Hybridon pursuant to Section 10.3 or 10.4: (a)
except with respect to any provision hereof that by its terms survives
termination and any payment obligation of Novartis that has accrued prior to the
date of termination, all rights and obligations of the Parties under this
License Agreement shall terminate; (b) all license rights granted by Hybridon to
Novartis hereunder shall revert to Hybridon; and (c) each Party shall return to
the other all Confidential Information of a Providing Party, provided, however,
that the Parties may each retain a copy of such Providing Party's Confidential
Information in segregated files solely for archival purposes.

            10.5.2. Upon termination of this License Agreement by Novartis
pursuant to Section 10.2 with respect to fewer than all the Products or
countries covered by this License Agreement: (a) except with respect to any
provision hereof that by its terms survives termination

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 35 OF 53
<PAGE>

and any payment obligation of Novartis that has accrued prior to the date of
termination, all rights and obligations of the Parties under this License
Agreement with respect to such country and/or Product subject to such
termination shall terminate; and (b) all license rights granted by Hybridon to
Novartis hereunder with respect to such country and/or Product subject to such
termination shall revert to Hybridon.

            10.5.3. In the case of termination by Novartis pursuant to Section
10.3, all rights of Novartis shall survive, and all rights of Hybridon shall
terminate other than Hybridon's rights under Sections 5.2 through 5.7 of Article
V (Milestone and Royalty Payments), except that the royalty payable to Hybridon
pursuant to Section 5.5 shall be reduced by [**] percent ([**]%) as provided in
Section 5.6.1, Section 14.6 (Force Majeure) and Articles VII (Confidentiality),
X (Term and Termination) and XIII (Indemnification).

            10.5.4. In the case of termination by Novartis pursuant to Section
10.4, all rights of Novartis shall survive, and all rights of Hybridon shall
terminate other than Hybridon's rights under Sections 5.2 through 5.7 of Article
V (Milestone and Royalty Payments), Section 14.6 (Force Majeure), and Articles
VII (Confidentiality), X (Term and Termination) and XIII (Indemnification).

                                   ARTICLE XI

                                   EXCLUSIVITY

      During the term of this License Agreement, Hybridon shall neither grant to
any Third Party rights to any immunomodulatory oligonucleotide other than
Excluded Antisense IP in the Commercial Field of Use, nor shall Hybridon develop
or commercialize, directly or indirectly, any immunomodulatory oligonucleotide
other than Excluded Antisense IP in the Commercial Field of Use. Furthermore,
during the term of this License Agreement, Hybridon shall neither grant to any
Third Party rights to any Licensed IMO for any indication, nor shall Hybridon
develop or commercialize, directly or indirectly, any such Licensed IMO.
Notwithstanding the foregoing, nothing in this License Agreement shall restrict
or prohibit Hybridon from performing its obligations or exercising its rights
under the Collaboration Agreement.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 36 OF 53
<PAGE>

                                   ARTICLE XII

                         REPRESENTATIONS AND WARRANTIES

         12.1. REPRESENTATIONS AND WARRANTIES OF HYBRIDON. Hybridon hereby
represents and warrants to Novartis that the statements in this Section 12.1 are
true and accurate as of the date of this License Agreement and as of the
Effective Date:

            12.1.1. Authorization. This License Agreement has been duly executed
and delivered by Hybridon and constitutes the valid and binding obligation of
Hybridon, enforceable against Hybridon in accordance with its terms, except as
enforceability may be limited by fraudulent conveyance, insolvency, bankruptcy,
reorganization, moratorium and other laws relating to or affecting creditors'
rights generally and by general equitable principles. The execution, delivery
and performance of this License Agreement have been duly authorized by all
necessary action on the part of Hybridon, its officers and directors. No
provision of this License Agreement violates any other agreement that Hybridon
may have with any other person or company, and Hybridon acknowledges that
Novartis has relied on that representation in entering into this License
Agreement.

            12.1.2. Hybridon Controlled Rights. Hybridon owns or possesses
adequate licenses or other rights to use all Hybridon Intellectual Property and
Hybridon Background Intellectual Property and to grant the licenses and perform
the obligations contemplated herein. The granting of the licenses to Novartis
hereunder does not violate any right known to Hybridon of any Third Party.

            12.1.3. Third Party Patents. Except as disclosed in writing between
the Parties to this License Agreement or their respective agents to Hybridon's
best knowledge, after reasonable inquiry, there are no issued patents or pending
patent applications that, if issued, would be infringed by the exercise by
Novartis of the rights granted herein or the research, development, manufacture,
use or sale of the Licensed IMOs pursuant to this License Agreement.

         12.2. REPRESENTATIONS AND WARRANTIES OF NOVARTIS. Novartis represents
and warrants to Hybridon that this License Agreement has been duly executed and
delivered by Novartis and constitutes the valid and binding obligation of
Novartis, enforceable against

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 37 OF 53
<PAGE>

Novartis in accordance with its terms except as enforceability may be limited by
fraudulent conveyance, insolvency, bankruptcy, reorganization, moratorium and
other laws relating to or affecting creditors' rights generally and by general
equitable principles. The execution, delivery and performance of this License
Agreement have been duly authorized by all necessary action on the part of
Novartis, its officers and directors. No provision of this License Agreement
violates any other agreement that Novartis may have with any other person or
company, and Novartis acknowledges that Hybridon has relied on that
representation in entering into this License Agreement.

         12.3. CERTIFICATE OF HYBRIDON. Within thirty (30) days of the Effective
Date, Hybridon shall deliver to Novartis a certificate or certificates, dated as
of the Effective Date, of the President of Hybridon certifying on behalf of
Hybridon that the representations and warranties of Hybridon set forth in this
License Agreement are true and correct on and as of the Effective Date. In the
event that the representations and warranties of Hybridon set forth in this
License Agreement are no longer true and correct on and as of the Effective
Date, without exception, Hybridon shall deliver to Novartis such certificate(s)
along with a detailed schedule of exceptions to such representations and
warranties (the "Schedule of Exceptions"). Upon delivery by Hybridon of
certificate(s) together with a Schedule of Exceptions (but not upon delivery of
certificate(s) not accompanied by a Schedule of Exceptions), Novartis, in its
sole discretion, shall either (i) withdraw its exercise of the Commercialization
Option, in which case this License Agreement shall be deemed not to have taken
effect, such Commercialization Option shall remain in full force and effect, and
Novartis shall retain the right to exercise such Commercialization Option at a
later time during the Option Term or (ii) accept the certificate as modified by
the Schedule of Exceptions, in which case this License Agreement shall remain
effective, the Schedule of Exceptions shall be incorporated herein as Schedule
12.3, and the option exercise fee set forth in Section 5.1 hereof shall become
payable by Novartis upon receipt of Invoice; provided that, (x) if Novartis does
not notify Hybridon that Novartis has elected to withdraw its exercise of the
Commericalization Option within sixty (60) days after Novartis receives such
certificate(s) together with a Schedule of Exceptions, Novartis shall be deemed
to have accepted the certificate(s) in accordance with the foregoing clause (ii)
and (y) if Hybridon delivers such certificate(s) together with a Schedule of
Exceptions, then Hybridon shall not Invoice Novartis for the option exercise fee
unless and until such certificate(s) have been

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 38 OF 53
<PAGE>

accepted (or deemed to have been accepted) by Novartis. Acceptance by Novartis
of a certificate modified by the Schedule of Exceptions shall in no way be
deemed to modify or otherwise limit Novartis' rights or possible remedies under
the Collaboration Agreement.

         12.4. LIMITATIONS.

            12.4.1. NO OTHER WARRANTIES. EXCEPT AS OTHERWISE EXPRESSLY SET FORTH
IN THIS AGREEMENT, ALL IMPLIED WARRANTIES, INCLUDING IMPLIED WARRANTIES OF
NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
EXCLUDED.

            12.4.2. CONSEQUENTIAL AND PUNITIVE DAMAGES. EXCEPT AS OTHERWISE
EXPRESSLY SET FORTH IN THIS AGREEMENT, NEITHER PARTY WILL BE LIABLE FOR
CONSEQUENTIAL, INCIDENTAL, MULTIPLE, SPECIAL OR PUNITIVE DAMAGES OF ANY NATURE
ARISING FROM SUCH PARTY'S ACTIVITIES UNDER THIS AGREEMENT; PROVIDED, HOWEVER,
THAT THIS LIMITATION SHALL NOT LIMIT THE INDEMNIFICATION OBLIGATIONS OF THE
PARTIES WITH RESPECT TO THIRD PARTY CLAIMS OR THE OBLIGATIONS OF EITHER PARTY
WITH RESPECT TO A BREACH OF ARTICLE II OR ARTICLE VII.

                                  ARTICLE XIII

                                 INDEMNIFICATION

         13.1. INDEMNIFICATION BY HYBRIDON. Hybridon will indemnify, defend, and
hold Novartis and its Affiliates, their respective employees, shareholders,
officers, directors, agents and consultants, and the successors, heirs and
assigns of each of them, harmless against any loss, damages, action, suit,
claim, demand, liability, expense, bodily injury, death or property damage,
including reasonable attorney fees (a "Loss") that may arise from Third Party
claims brought, instituted or arising against such persons to the extent such
Loss is based on or arises out of the breach by Hybridon of any of its
covenants, representations or warranties set forth in this License Agreement,
but excluding any such Loss that is caused by the negligent, willful or reckless
acts or omissions of Novartis.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 39 OF 53
<PAGE>

         13.2. INDEMNIFICATION BY NOVARTIS. Novartis will indemnify, defend, and
hold Hybridon, and its Affiliates, and their respective employees, shareholders,
officers, directors, agents and consultants, and the successors, heirs, and
assigns of each of them, harmless against any Loss that may arise from Third
Party claims brought, instituted or arising against such persons to the extent
such Loss is based on or arises out of (a) the breach by Novartis of any of its
covenants, representations or warranties set forth in this License Agreement,
(b) the development, manufacture, use, storage or handling of a Licensed IMO by
Novartis or its Affiliates or their representatives, agents, licensees,
sublicensees or subcontractors under this License Agreement, or any actual or
alleged violation of law resulting therefrom, including without limitation any
death or bodily injury caused or allegedly caused by the use of the Licensed IMO
or (c) any actual or alleged infringement of any patent rights, trademarks or
other intellectual property rights, or misappropriation of trade secrets, in
connection with the making, having made, using, having used, developing, having
developed, commercializing, having commercialized, manufacturing, having
manufactured, promoting, having promoted, selling, having sold, distributing,
having distributed, marketing, having marketed, importing, having imported,
exporting or having exported of any Licensed IMO or Product, but excluding any
such Loss that is caused by the negligent, willful or reckless acts or omissions
of Hybridon.

         13.3. CLAIMS PROCEDURES. Each Person entitled to be indemnified by a
Party (an "Indemnified Person") pursuant to Sections 13.1 or 13.2 hereof shall
give notice to the other Party (an "Indemnifying Party") promptly after such
Indemnified Person has actual knowledge of any threatened or asserted claim as
to which indemnity may be sought, and shall permit the Indemnifying Party to
assume the sole control of the defense of any such claim or any litigation
resulting therefrom; provided, however:

         (a) that counsel for the Indemnifying Party, who shall conduct the
defense of such claim or any litigation resulting therefrom, shall be approved
by the Indemnified Person (whose approval shall not unreasonably be withheld)
and the Indemnified Person may participate in such defense at such Party's
expense (unless: (i) the employment of counsel by such Indemnified Person has
been authorized by the Indemnifying Party; or (ii) the Indemnified Person shall
have reasonably concluded that there may be a conflict of interest between the
Indemnifying Party and the Indemnified Person in the defense of such action, in
each of which cases the Indemnifying

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 40 OF 53
<PAGE>

Party shall pay the reasonable fees and expenses of one law firm serving as
counsel for all Indemnified Persons with respect to such action, which law firm
shall be subject to approval, not to be unreasonably withheld, by the
Indemnifying Party);

         (b) the failure of any Indemnified Person to give notice as provided
herein shall not relieve the Indemnifying Party of its obligations under this
License Agreement to the extent that the failure to give notice did not result
in harm to the Indemnifying Party or materially compromise the defense of such
claim;

         (c) no Indemnifying Party, in the defense of any such claim or
litigation, shall consent to entry of any judgment or enter into any settlement,
except with the approval of each Indemnified Person (which approval shall not be
unreasonably withheld), except a settlement which imposes only a monetary
obligation on the Indemnifying Party and which includes as an unconditional term
thereof the giving of a release from all liability in respect to such claim or
litigation by the claimant or plaintiff to the Indemnified Person;

         (d) each Indemnified Person shall furnish such information or
reasonable assistance regarding itself or the claim in question as an
Indemnifying Party may reasonably request in writing and shall be reasonably
required in connection with the defense of such claim and litigation resulting
therefrom; and

         (e) no Indemnified Person shall settle or agree to a judgment with
respect to such claim or litigation without the consent of the Indemnifying
Party (which consent shall not be unreasonably withheld).

         13.4. SURVIVAL. The provisions of this Article XIII shall survive
expiration or termination of this Agreement without limitation.

                                   ARTICLE XIV

                            MISCELLANEOUS PROVISIONS

         14.1. INVOICE REQUIREMENT. Except as otherwise set forth in Section
6.1, any amounts payable to Hybridon hereunder shall be made within sixty (60)
calendar days after receipt by Novartis or its designated nominee of an invoice
covering such payment. With respect

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 41 OF 53
<PAGE>

to invoices for milestone payments, Hybridon shall send such invoices following
written notice by Novartis that the particular milestone(s) to which such
invoice pertains has been met.

         14.2. GOVERNING LAW, AND JURISDICTION. This License Agreement shall be
governed and construed in accordance with the internal laws of the State of New
York, United States. Both Parties agree to submit to personal jurisdiction in
the State of New York and to accept and agree to venue in the State of New York.

         14.3. ARBITRATION WITH RESPECT TO CERTAIN MATTERS. Any controversy or
claim as to whether this License Agreement may be terminated by a Party pursuant
to Section 10.3 (any such controversy or claim being referred to in this Section
14.3 as a "Section 10.3 dispute") shall be resolved through arbitration as
follows:

            14.3.1. Notice; Selection of Arbitrators. A Party may submit such
Section 10.3 dispute to arbitration by notifying the other Party, in writing, of
such Section 10.3 dispute. The Party submitting such notice shall include
therein a reasonably detailed summary of the basis for such Section 10.3
dispute. The Parties agree that any such Section 10.3 dispute shall be submitted
to three (3) arbitrators selected from the panel of arbitrators of the American
Arbitration Association ("AAA"). Within twenty (20) days after receipt of notice
pursuant to this Section 14.3.1, each Party shall designate in writing a single
arbitrator. Within ten (10) business days after the designation of the
arbitrators, the arbitrators chosen by the Parties shall choose a third
arbitrator (collectively, the "Arbitrators"). In selecting the third arbitrator,
preference shall be given to a lawyer or former judge knowledgeable and
experienced in the law concerning the subject matter of the Section 10.3
dispute, and shall not be an Affiliate, employee, consultant, officer, director
or stockholder of either Party. The Parties shall obtain the agreement of the
Arbitrators to provide a written ruling, stating in separate sections the
findings of fact and conclusions of law on which their ruling is based. The
Parties will obtain the agreement of the Arbitrators to the terms of this
Section 14.3.

            14.3.2. Initial Meeting. Within ten (10) days after the designation
of the Arbitrators, the Arbitrators and the Parties shall meet, at which time
the Parties shall be required to set forth in writing all disputed issues and a
proposed ruling on the merits of each such issue.

       License, Development and Commercialization Agreement - Confidential

                                  PAGE 42 OF 53
<PAGE>

            14.3.3. Hearing. The Arbitrators shall set a date for a hearing,
which shall be no later than twenty (20) days after the submission of written
proposals pursuant to Section 14.3.2, to discuss each of the issues identified
by the Parties. The Parties shall have the right to be represented by counsel.
Except as provided herein, the arbitration shall be governed by the Commercial
Arbitration Rules of the AAA, as amended and in effect on the date a demand for
arbitration is filed; provided, however, that the United States Federal Rules of
Evidence shall apply with regard to the admissibility of evidence.

            14.3.4. Ruling. The Arbitrators shall use their best efforts to rule
on the Section 10.3 dispute within twenty (20) days after the completion of the
hearing described in Section 14.3.3. Subject to any rights to appeal provided
for by statute, the determination of the Arbitrators as to the resolution of any
Section 10.3 dispute shall be binding and conclusive upon both Parties. All
rulings of the Arbitrators shall be in writing, specifying the basis in law and
in fact of the ruling, and shall be delivered to the Parties.

            14.3.5. Costs and Expenses. Each Party shall bear its own costs and
expenses incurred in connection with any arbitration pursuant to this Section
14.3.

            14.3.6. Location of Arbitration. Any arbitration pursuant to this
Section 14.3 shall be conducted in New York, New York. Any arbitration award may
be entered in and enforced by a court in accordance with Section 14.2, subject
to each Party's rights to appeal as provided for by statute.

            14.3.7. No Limitation. Nothing in this Section 14.3 shall be
construed as limiting in any way the right of a Party to bring an action in aid
of arbitration in a court in accordance with Section 14.2.

         14.4. SAFETY ISSUES OR SIGNALS. During the term of this License
Agreement, the Parties will promptly report to appropriate authorities in
accordance with applicable law any safety issue or signal, directly or
indirectly attributable to such Party's use or application of any
immunomodulatory oligonucleotide and shall share any such report with the other
Party. Each Party shall be entitled to use and disclose all such reports or
other information to regulatory authorities as required under applicable law or
regulation and to licensees, sublicensees and collaborators under obligations of
confidentiality for purposes relating to the research,

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 43 OF 53
<PAGE>

development and/or commercialization of products incorporating immunomodulatory
oligonucleotides.

         14.5. WAIVER. No provision of this License Agreement may be waived
except in writing by both Parties. No failure or delay by either Party in
exercising any right or remedy hereunder or under applicable law will operate as
a waiver thereof, or a waiver of any right or remedy on any subsequent occasion.

         14.6. FORCE MAJEURE. Neither Party will be in breach hereof by reason
of its delay in the performance of or failure to perform any of its obligations
hereunder, if that delay or failure is caused by strikes, acts of God or the
public enemy, riots, war, terrorism, incendiaries, interference by civil or
military authorities, compliance with governmental priorities for materials, or
any fault beyond its control or without its fault or negligence.

         14.7. SEVERABILITY. Should one or more provisions of this License
Agreement be or become invalid, then the Parties shall attempt in good faith to
agree upon valid provisions in substitution for the invalid provisions, which in
their economic effect and other substance come so close to the invalid
provisions that it can be reasonably assumed that the Parties would have
accepted this License Agreement with those new provisions. If the Parties are
unable to agree on such valid provisions, the invalidity of such one or more
provisions of this License Agreement shall nevertheless not affect the validity
of the License Agreement as a whole, unless the invalid provisions are of such
essential importance for this License Agreement that it may be reasonably
presumed that the Parties would not have entered into this License Agreement
without the invalid provisions.

         14.8. GOVERNMENT ACTS. In the event that any act, regulation,
directive, or law of a country or its government, including its departments,
agencies or courts, should make impossible or prohibit, restrain, modify or
limit any material act or obligation of the Parties under this License
Agreement, the Party, if any, not so affected, shall have the right, at its
option, to suspend or terminate this License Agreement as to such country, if
good faith negotiations between the Parties to make such modifications herein as
may be necessary to fairly address the impact thereof, are not successful after
a reasonable period of time in producing mutually acceptable modifications to
this License Agreement.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 44 OF 53
<PAGE>

         14.9. GOVERNMENT APPROVALS. Each Party will obtain any government
approval required to enable this License Agreement to become effective, or to
enable any payment hereunder to be made, or any other obligation hereunder to be
observed or performed. Each Party shall keep the other informed of progress in
obtaining any such government approval, and will cooperate with the other Party
in any such efforts.

         14.10. EXPORT CONTROLS. This License Agreement is made subject to any
restrictions concerning the export of a Licensed IMO, Product, Hybridon
Intellectual Property, Hybridon Background Intellectual Property, or Joint
Intellectual Property from the United States that may be imposed upon or related
to either Party from time to time by the Government of the United States.
Furthermore, each Party agrees that it will not export, directly or indirectly,
any Hybridon Intellectual Property, Hybridon Background Intellectual Property,
Joint Intellectual Property or a Licensed IMO or Product utilizing the same to
any countries for which the United States government or any agency thereof at
the time of export requires an export license or other governmental approval,
without first obtaining the written consent to do so (of which Novartis will
promptly inform Hybridon) from the Department of Commerce or other agency of the
United States government when required by applicable statute or regulation.

         14.11. ASSIGNMENT. This License Agreement may not be assigned or
otherwise transferred by either Party without the prior written consent of the
other Party; provided, however, that either Party may assign this License
Agreement, without the consent of the other Party: (a) to any of its Affiliates,
if the assigning Party guarantees to full performance of its Affiliates'
obligations hereunder; or (b) in connection with the transfer or sale of all or
substantially all of its assets or business to which this License Agreement
pertains, or a controlling equity interest, or in the event of its merger or
consolidation with another company. Any purported assignment in contravention of
this Section 14.11 shall, at the option of the nonassigning Party, be null and
void and of no effect. No assignment shall release either Party from
responsibility for the performance of any accrued obligation of such Party
hereunder. This License Agreement shall be binding upon and enforceable against
the successor to or any permitted assignees of either of the Parties.

         14.12. COUNTERPARTS. This License Agreement may be executed in
counterparts, each of which shall be deemed to be original and both of which
shall constitute one and the same

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 45 OF 53
<PAGE>

License Agreement.

         14.13. NO AGENCY. Nothing in this License Agreement shall be deemed to
create an agency, joint venture, amalgamation, partnership or similar
relationship between Hybridon and Novartis and/or their respective Affiliates.
Notwithstanding any of the other provisions of this License Agreement, neither
Party shall at any time enter into, incur, or hold itself out to Third Parties
as having authority to enter into or incur, on behalf of the other Party, any
commitment, expense, or liability whatsoever, and all contracts, expenses and
liabilities in connection with or relating to the obligations of each Party
under this License Agreement shall be made, paid, and undertaken exclusively by
such Party on its own behalf and not as an agent or representative of the other.

         14.14. NOTICE. All communications between the Parties with respect to
any of the provisions of this License Agreement will be sent to the addresses
set out below, or to such other addresses as may be designated by one Party to
the other by notice pursuant hereto, by (i) personal delivery (which shall be
deemed received when delivered), (ii) reputable international express courier
(which shall be deemed received when delivered), (iii) prepaid, certified mail
(which shall be deemed received by the other party on the seventh (7th) business
day following deposit in the mails), or (iv) facsimile transmission, or other
electronic means of communication (which shall be deemed received when
transmitted), with confirmation in the case of clause (iv) prepaid certified
mail, given by the close of business on or before the next following business
day:

            if to Novartis, at:

                Novartis International Pharmaceutical Ltd.
                Hurst Holme
                12 Trott Road
                P.O. Box 2899
                Hamilton, HM LX
                Bermuda
                Attention: Emil Bock
                Fax: (441) 296-5083

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 46 OF 53
<PAGE>

            with a copy to:

                Novartis Institutes for BioMedical Research, Inc.
                400 Technology Square
                Cambridge, Massachusetts 02139
                Attention: Robert L. Thompson, Vice President and General
                 Counsel
                Fax: [**]
            and:

                Novartis Pharma AG
                Lichtstrasse 35
                CH-4056 Basel
                Switzerland
                Attn.: General Counsel
                Fax: [**]

            if to Hybridon, at:

                Hybridon, Inc.
                345 Vassar Street
                Cambridge, Massachusetts  02139
                Attention: President
                Fax: +(617) 679-5542

            with a copy to:

                Wilmer Cutler Pickering Hale and Dorr LLP
                60 State Street
                Boston, Massachusetts 02109
                USA
                Attention: David E. Redlick, Esq.
                Fax: +(617) 526-5000

         14.15. HEADINGS. The paragraph headings are for convenience only and
will not be deemed to affect in any way the language of the provisions to which
they refer.

         14.16. AUTHORITY. The undersigned represent that they are authorized to
sign this License Agreement on behalf of their respective Party. The Parties
each represent that no provision of this License Agreement will violate any
other agreement that such Party may have with any other person or company. Each
Party has relied on that representation in entering into this License Agreement.

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 47 OF 53
<PAGE>

         14.17. ENTIRE AGREEMENT. This License Agreement and the Collaboration
Agreement contain the entire understanding of the Parties relating to the
matters referred to herein and therein, supersede all prior agreements between
the Parties with respect to such matters (including without limitation the
Confidential Term Sheet dated January 26, 2005, the Material Transfer Agreement
dated July 1, 2003, as amended prior to the Effective Date, and the Mutual
Confidentiality Agreements dated January 23, 2003 and June 8, 2004, each as
amended prior to the Effective Date, but excluding provisions of such Material
Transfer Agreement and Mutual Confidentiality Agreements, relating to
restrictions on the use and disclosure of materials and information prior to the
Effective Date (it being understood that any material and information
transferred or disclosed between the Parties prior to the Effective Date
relating to the matters referred to in this License Agreement and the
Collaboration Agreement will, after the Effective Date, be deemed to have been
transferred or disclosed under, and will be subject to the restrictions on use
and disclosure set forth in, this License Agreement and the Collaboration
Agreement)), and may only be amended by a written document, duly executed on
behalf of the respective Parties.

                            [Signature page follows]

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 48 OF 53
<PAGE>

                                    HYBRIDON, INC.

                                    By: /s/ Sudhir Agrawal
                                        ----------------------------------------

                                    Name: Sudhir Agrawal

                                    Title: CEO/President

                                    NOVARTIS INTERNATIONAL PHARMACEUTICAL LTD.

                                    By: /s/ Emil Bock
                                        ----------------------------------------

                                    Name: Emil Bock

                                    Title: Member of the Board of Directors.

                                    By: /s/ Michael Jones
                                        ----------------------------------------

                                    Name: Michael Jones

                                    Title: Member of the Board of Directors

       License, Development and Commercialization Agreement - Confidential

                                 PAGE 49 OF 53
<PAGE>

                                                                       EXHIBIT A
                                 SAMPLE INVOICE

HYBRIDON'S LOGO                                                    INVOICE

                                                               INVOICE DATE:
Street                                                         [MONTH][DAY] 200X
Town, Country
Phone and Fax Nr.                                              INVOICE NO.:XXXX

BILL TO:                                             FOR:
Novartis International Pharmaceutical Ltd.           Product X Royalties 1st
"Hurst Holme", 12 Trott Road                          Quarter 2004
Att. Mr. Emil Bock                                   (or Milestone for event Y)
P.O. Box HM 2899
Hamilton, HM LX
Bermuda

<TABLE>
<CAPTION>
                          DESCRIPTION                              AMOUNT (USD)
------------------------------------------------------------      --------------
<S>                                                               <C>
Product X royalties January - March 2004 calculated based on      US$ 000'000.00
Novartis provided sales report (see attached worksheet)

(Or milestone payment for event Y, according to paragraph XY
of agreement ZZZZ dated ......)

Novartis Contract Code

Please specify the event for which the invoice is due, and
add any copies of invoices from third parties in case
reimbursement for third party work is agreed to

PLEASE REMIT BY WIRE TRANSFER WITHIN 60 DAYS TO:

                Receiving Bank -
                Swift Code -
                ABA Number -
                Credit Account -
                Beneficiary -
                                                                  --------------
                                                       TOTAL          000'000,00
                                                                  ==============
</TABLE>

If you have any questions concerning this invoice, contact ..........
or e-mail to ......

VAT -Reg. No. Xxxxxxxxxx (if partner has one)

                        BEST REGARDS,

<PAGE>

                                  SCHEDULE 1.29
                                HYBRIDON PATENTS

         [TO BE APPENDED UPON EXERCISE OF THE COMMERCIALIZATION OPTION]

<PAGE>

                                  SCHEDULE 1.39
                                  JOINT PATENTS

         [TO BE APPENDED UPON EXERCISE OF THE COMMERCIALIZATION OPTION]

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00088-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00088-of-00352.parquet"}]]