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                                                                    EXHIBIT 10.7

                             CONFIDENTIAL TREATMENT


                       COOPERATION AND LICENSING AGREEMENT

This Agreement (AGREEMENT) is entered into as of the 31st of December, 2001
(EFFECTIVE DATE) between NeoGenesis Pharmaceuticals, Inc., a Delaware
corporation (NEOGENESIS) and Aventis Pharma S.A., a corporation organized under
the laws of France and having a place of business at 20, avenue Raymond Aron,
92160 Antony, France (together with its Affiliates, AVENTIS), and sets forth the
terms and conditions that will apply to the provision by NeoGenesis to Aventis
of certain screening and analysis services.

                                   BACKGROUND

Aventis is interested in identifying potential pharmaceutical products for
treatment of certain human diseases and wishes to identify compounds that
exhibit a high degree of chemical binding and functional activity to specific
protein targets. NeoGenesis has certain technology and know-how, including
screening processes of libraries of mass-encoded small molecule compounds,
relating to the identification, discovery, validation and optimization of novel
compounds which may be useful for development of novel therapeutics employing
targets implicated in a disease process. The parties wish to pursue a
collaborative screening process to identify compounds exhibiting a high degree
of chemical binding affinity to and biological activity against targets
designated by Aventis from among the NeoGenesis libraries of mass-encoded small
molecule compounds and which have activity in bioassays or functional assays.
The terms and conditions set forth below shall govern the performance of such
collaborative effort.

1.  DEFINITIONS.

1.1 DEFINED TERMS. Capitalized terms used in this Agreement and not otherwise
defined herein shall have the meaning set forth below.

     AFFILIATE means with respect to either party, any Person that, directly or
indirectly, is controlled by, controls or is under common control with such
party. For purposes of this definition, CONTROL means, with respect to any
Person, the direct or indirect ownership of more than fifty percent (50%) of the
equity (or such lesser percentage which is the maximum allowed to be owned by a
foreign corporation, in a particular jurisdiction) having the power to vote on
or direct the management or policies of such Person.

     ALIS means the Automated Ligand Identification System, an automated,
ultra-high throughput ligand selection system proprietary to NeoGenesis that is
used to identify multiple classes of chemical ligands against a specific target
protein.

     APPLICABLE LAWS means all laws, statutes, regulations and ordinances of any
Regulatory Authority, including without limitation the FD&C Act.

     AVENTIS INTELLECTUAL PROPERTY means, individually and collectively, (a) all
Inventions that are conceived, discovered, developed, generated, created, made
or reduced to practice or tangible medium of expression solely by employees or
consultants of Aventis at any time prior to the Effective Date or after the
Effective Date if such Inventions are not based upon or related to the
performance of the Program; (b) any tangible materials provided by Aventis to
NeoGenesis for use in the conduct of the Program, together with, where
applicable, any analogs, derivatives, fragments, progeny, sub-cellular
constituents or expression products thereof; (c) the Targets or the uses
thereof; and (d) the functional assays provided by Aventis under the Program.
The term Aventis Intellectual Property, however, does not include any know-how,
processes, information and data which is, as of the Effective Date or later
becomes, generally available to the public.

     AVENTIS PATENT RIGHTS means (a) those patents and patent applications
covering Aventis Intellectual Property and Program Intellectual Property owned
by Aventis that are Controlled by Aventis at any time during the term of this
Agreement which (i) relate to or otherwise would be infringed by the
manufacture, use, importation or sale of any Lead Compound or Product or (ii)
relate to Aventis Intellectual Property and (b) all divisionals, continuations,
continuations-in-part, reissues, extensions, supplementary protection
certificates and foreign counterparts thereof.

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     COMMERCIALLY REASONABLE EFFORTS means, with respect to (i) any objective by
any party, reasonable, diligent, good faith efforts to accomplish such objective
as such party would normally use to accomplish a similar objective under similar
circumstances; and (ii) with respect to any objective relating to the
development or Commercialization of any Product by any party efforts and
resources normally used by such party with respect to a product owned by such
party or to which such party has similar rights which is of similar market
potential at a similar stage in the development or life of such product, taking
into account issues of safety, efficacy, the competitiveness of the marketplace,
the proprietary position of the product, the regulatory structure involved, and
profitability of the product.

     COMMERCIALIZATION means any and all activities of marketing, promoting,
distributing, offering for sale and selling a Product to a non-Affiliated third
party. When used as a verb, COMMERCIALIZE means to engage in Commercialization.

     CONFIDENTIAL INFORMATION means any proprietary or confidential information
of either party (including but not limited to all Aventis Intellectual Property
and all NeoGenesis Intellectual Property) disclosed to the other party pursuant
to this Agreement in written, electronic or other tangible medium and marked as
confidential, or if disclosed orally or displayed or disclosed in tangible
medium without a confidential marking, confirmed in a writing (describing the
information and referencing the place and date of such oral, visual, electronic
or written disclosure and the names of the persons to whom such disclosure was
made) within thirty (30) days of disclosure, except any portion thereof which:
(i) is known to the receiving party, as evidenced by the receiving party's
written records, before receipt thereof under this Agreement; (ii) is disclosed
to the receiving party by a third person who is under no obligation of
confidentiality to the disclosing party hereunder with respect to such
information and who otherwise has a right to make such disclosure; (iii) is or
becomes generally known in the trade through no fault of the receiving party; or
(iv) is independently developed by the receiving party, as evidenced by the
receiving party's written records, without access to such information.
Additionally any technical or financial information disclosed by either Party at
a meeting of the Steering Committee or disclosed through an audit report shall
constitute Confidential Information unless otherwise specified.

     CONTROL OR CONTROLLED means with respect to: (a) any item of information,
including, without limitation, Aventis Intellectual Property and NeoGenesis
Intellectual Property, or (b) any intellectual property rights, the possession
(whether by ownership or license, other than pursuant to this Agreement) by a
party or an Affiliate thereof of the ability to grant to the other party access
or a license as provided herein under such item of information or intellectual
property rights without violating the terms of any agreement or other
arrangements, between such party or its Affiliate and any third party, existing
before or after the Effective Date.

DERIVATIVE COMPOUNDS means any analog, homolog or isomer of a Lead Compound,
which has an IC50 value against the Screening Target of [*] micromolar or less,
which (a) results from a chemical synthesis program based on the Lead Compounds
or (b) is based on structure-activity data of the Lead Compound; PROVIDED, that
any such program or data is in respect of a target protein from other bacterial
or fungal organisms homologous in origin and biological function to the original
Screening Target.

     EMEA means the European Medical Evaluation Agency and any successor agency
thereto.

     FDA means the United States Food and Drug Administration, or any successor
thereto.

     FD&C ACT means the United States Federal Food, Drug and Cosmetic Act of
1938, as amended.

     FIELD means preventative, therapeutic and diagnostic uses in humans or
animals.

     FIRST COMMERCIAL SALE of Product(s) means any transfer for value in an
arms-length transaction to an independent third party distributor, agent or end
user in a country within the Territory after obtaining all necessary Regulatory
Approvals as may be necessary for such transfer in such country.

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     FORCE MAJEURE means any event beyond the control of the parties, including,
without limitation, failures of computers, computer-related equipment, hardware
or software, fire, flood, riots, strikes, epidemics, war (declared or undeclared
and including the continuance, expansion or new outbreak of any war or conflict
now in existence), embargoes and governmental actions or decrees.

     FTE means a full time equivalent person year (consisting of a total of 1880
hours per year) of scientific, technical or managerial work, carried out by one
or more employees or agents of NeoGenesis, who devotes a portion of his or her
time to performing further optimization activities as set forth herein.

     FTE RATE means the amount charged per FTE, such amount not to exceed [*].

     GOOD CLINICAL PRACTICE means the then current standards for clinical trials
for pharmaceuticals, as set forth in the FD&C Act and applicable regulations
promulgated thereunder, as amended from time to time, and such standards of good
clinical practice as are required by the European Union and other Regulatory
Authorities in countries in which the Product is intended to be sold, to the
extent such standards are not in contravention with United States Good Clinical
Practices.

     GOOD LABORATORY PRACTICE means the then current standards for laboratory
activities for pharmaceuticals, as set forth in the FD&C Act and applicable
regulations promulgated thereunder, as amended from time to time, and such
standards of good laboratory practice as are required by the European Union and
other Regulatory Authorities in countries in which the Product is intended to be
sold, to the extent such standards are not in contravention with United States
Good Laboratory Practices.

     GOOD MANUFACTURING PRACTICE means the current standards for the manufacture
of pharmaceuticals, as set forth in the FD&C Act and applicable regulations
promulgated thereunder, as amended from time to time, and such standards of good
manufacturing practice as are required by the European Union and other
Regulatory Authorities in countries in which the Product is intended to be sold,
to the extent such standards are not in contravention with United States Good
Manufacturing Practices.

     IND means an investigational new drug application, as defined in the FD&C
Act and applicable regulations thereunder, or any equivalent document, filed
with the FDA and necessary for beginning clinical trials of any Product in
humans or any equivalent application or other documentation filed with any
Regulatory Authority of a country other than the United States prior to
beginning clinical trials of any Product in humans in that country.

     INVENTION(S) means all discoveries, inventions, know-how, trade secrets,
techniques, methodologies, modifications, improvements, works of authorship,
designs and data (whether or not protectable under patent, copyright, trade
secrecy or similar laws).

     LEAD COMPOUND means those Hit Compounds (or any analogs, homologs or
isomers of such Hit Compounds) that Aventis classifies as leads for further
research based on Aventis' good faith evaluation of the satisfaction of the
following criteria by such Hit Compound (or analogs, homologs or isomers of
such Hit Compound): (a) such Hit Compound is clearly optimized towards target
product profile; (b) SAR established on a series of more than [*] related
compounds including the Hit Compound and analogs, homologs or isomers of such
Hit Compound; (c) clear optimization potential for the Hit Compound (or
analogs, homologs or isomers of such Hit Compound) identified; (d)
satisfactory eADME [*] profile; (e) first in class in vivo PK; (f) other
preliminary in vivo data if accessible; (g) electrophysiology HERG assay when
appropriate; and (h) other secondary assays needed to pursue such Selected
Compound.

     MAJOR COUNTRY mean the United States, the United Kingdom, France, Germany
or Italy, as the case may be.

     MANUFACTURING means any and all activities involved in the production of a
Product to be developed and/or Commercialized under this Agreement. When used as
a verb, MANUFACTURE means to engage in Manufacturing.

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     NDA means a new drug application as defined in the FD&C Act and applicable
regulations thereunder, and/or the non-U.S. equivalent thereof.

     NEOGENESIS INTELLECTUAL PROPERTY means, individually and collectively, (a)
all Inventions that are conceived, discovered, developed, generated, created,
made or reduced to practice or tangible medium of expression solely by employees
or consultants of NeoGenesis at any time prior to the Effective Date or after
the Effective Date (if such Inventions are not based upon or related to the
performance of the Program); (b) any tangible materials provided by NeoGenesis
to Aventis for use in the conduct of the Program, together with, where
applicable, any analogs, derivatives, fragments, progeny, sub-cellular
constituents or expression products thereof; and (c) the NeoMorph Screening
Library, the NeoMorph Focused Libraries, ALIS and QSCD. The term NeoGenesis
Intellectual Property, HOWEVER, does not include any know-how, processes,
information and data which is, as of the Effective Date or later becomes,
generally available to the public.

     NEOGENESIS PATENT RIGHTS means those (a) patents and patent applications
covering NeoGenesis Intellectual Property and Program Intellectual Property
owned by NeoGenesis listed in ATTACHMENT D, as ATTACHMENT D is amended from time
to time in accordance with Section 2.6 or Section 3.3, which are Controlled by
NeoGenesis; and (b) all divisionals, continuations, continuations-in-part,
reissues, extensions, supplementary protection certificates and foreign
counterparts thereof which are Controlled by NeoGenesis and are existing as of
the Effective Date or filed or issued during the term of this Agreement.

     NEOMORPH CHEMISTRY means the process, proprietary to NeoGenesis, of forming
libraries and sub-libraries of discrete compounds by coupling a broad set of
diverse cores with diverse sets of building blocks employing proprietary
mass-coding algorithms.

     NEOMORPH FOCUSED LIBRARIES means those compounds synthesized by NeoGenesis
derived from Primary Active Compounds identified by Aventis in bioassays or
functional assays

     NEOMORPH SCREENING LIBRARY means the entire collection of libraries
consisting of mass-encoded small molecule organic compounds owned by NeoGenesis
and developed with NeoMorph Chemistry, currently comprising approximately
10,000,000 different compounds.

     NET SALES means the aggregate amount invoiced by Aventis, its Affiliates or
any of its sublicensees to a third party distributor (who is not a sublicensee),
agent, contractor or end user for the sale of the Product (other than sales of
Products at cost by Aventis, its Affiliates or sublicensees to a third party for
use in a clinical study prior to regulatory approval of such Product) LESS
deductions selected as appropriate from: (a) credits, refunds and allowances
separately and actually credited to customers for defective, spoiled, damaged,
outdated, and returned Products, (b) offered and taken trade volume and cash
discounts and rebates in amounts customary to the trade, (d) sales, excise,
value added, turnover, use, and other like taxes, and customs duties, paid,
absorbed or allowed excluding net income tax, to the extent invoiced, (e)
compulsory payments and rebates accrued, paid or deducted pursuant to agreements
with third party payors or administrators (including but not limited to managed
care agreements) or government regulations, (f) outbound packing,
transportation, insurance and handling charges that are separately billed to the
customer or prepaid to the extent invoiced, and (g) price adjustments (including
retro-active price adjustments) separately and actually credited to customers.
The amounts of any deductions taken pursuant to clauses (a)-(g) shall be
determined from books and records maintained in accordance with GAAP,
consistently applied. Net Sales shall not include revenue received by Aventis
(or any of its Affiliates) from transactions with an Affiliate, where the
Product in question will be resold to an independent third-party distributor,
agent or end user by the Affiliate where such revenue received by the Affiliate
from such resale is included in Net Sales in accordance with Section 4.6.

     PERSON means any individual, corporation, association, partnership (general
or limited), joint venture, trust, estate, limited liability company, limited
liability partnership, unincorporated organization, government (or any agency or
political subdivision thereof) or other legal entity or organization.

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     PRODUCT(S) means any product: (a) made up of, comprising or containing a
Lead Compound or a Derivative Compound; and (b) the development, manufacture,
use, or sale of which, absent the license granted to Aventis under Section 3.1
OR the rights assigned to Aventis under Section 3.2(d) of this Agreement, would
infringe the NeoGenesis Intellectual Property or NeoGenesis Patent Rights or
which makes use of any Program Patent Rights with respect to which NeoGenesis is
an inventor (in accordance under U.S. patent law).

     PROGRAM means, collectively, the screening program described in Paragraphs
1-6 of ATTACHMENT A (the SCREENING PROGRAM) and the optimization program
described in Paragraphs 7-8 of ATTACHMENT A (the HIT EXPLORATION PROGRAM) as the
same may be amended during the term of this Agreement by mutual agreement of the
parties acting through the Steering Committee (as defined below). The Screening
Program will be directed toward the discovery and development of Hits for the
Screening Targets and the Hit Exploration Program will be directed toward the
development of Lead Compounds for the Screening Targets.

     PROGRAM INTELLECTUAL PROPERTY means individually and collectively all
Inventions that are conceived, created, discovered, developed, generated, made
or reduced to practice or tangible medium of expression: (a) solely by one or
more employees or consultants of NeoGenesis at any time if such Inventions are
based upon or related to the performance of the Program; (b) jointly by one or
more employees or consultants of NeoGenesis and one or more employees or
consultants of Aventis at any time if such Inventions are based upon or related
to the performance of the Program; or (c) solely by one or more employees or
consultants of Aventis at any time if such Inventions are based upon or related
to the performance of the Program. Program Intellectual Property is listed in
ATTACHMENT B, which shall be amended from time-to-time to include new Program
Intellectual Property, in accordance with Section 3.3.

     PROGRAM PATENT RIGHTS means (a) those patents and patent applications, the
claim of which covers all or any part of Program Intellectual Property, and (b)
all divisionals, continuations, continuations-in-part, reissues, extensions,
supplementary protection certificates and foreign counterparts thereof.

     QSCD means Quantized Surface Complementary Diversity, a model proprietary
to NeoGenesis, in terms of which discrete chemical compliments to the surfaces
of a Target are defined.

     R&D PROGRAM means on a Lead Compound-by-Lead Compound basis the activities
necessary to be undertaken in connection with the research and development of
such Lead Compound prior to obtaining Regulatory Approval for a Product
(regardless of the country in which such activities are conducted).

     REGULATORY APPROVALS means, for any country in the Territory, those
authorizations by the appropriate Regulatory Authority(ies) required for the
manufacture, importation, marketing, promotion, pricing and sale of the
Product(s) in such country.

     REGULATORY AUTHORITY means any national, supra-national, regional, state or
local regulatory agency, department, bureau, commission, council or other
governmental entity in the Territory, including, without limitation, the FDA and
the EMEA.

     SCREENING TARGET means a specific protein target - selected by Aventis for
which NeoGenesis will perform the Program and for which the screening fee
described in Section 4.1, the success payment described in Section 4.4, the
milestone payments described in Section 4.5 and royalties described in Section
4.6 are due from Aventis to NeoGenesis as specified in Section 4. An Excluded
Target is not a Screening Target for purposes of this Agreement until such time
as it becomes a Screening Target. The initial Screening Targets are identified
in ATTACHMENT C.

     TERRITORY means all the countries of the world.

1.2 OTHER  DEFINED  TERMS.  The  following  terms  shall have the  meanings
set forth in the section appearing opposite such term:

<Table>
         <S>                                         <C>
         AAA                                         Section 9.1
         AGREEMENT                                   Recitals

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         AVENTIS                                     Recitals
         BANKRUPTCY CODE                             Section 3.1
         DISPUTE NOTICE                              Section 9.1
         EFFECTIVE DATE                              Recitals
         EXCLUDED TARGET                             Section 2.2
         FINAL TARGET REPORT                         ATTACHMENT A
         GENERIC RIGHTS                              Section 3.2
         HIT COMPOUND(S)                             ATTACHMENT A
         HIT EXPLORATION PROGRAM                     C.F. PROGRAM
         INDEMNIFIED PARTY(IES)                      Section 7.2
         INDEMNIFYING PARTY                          Section 7.2
         LICENSED TECHNOLOGY                         Section 3.1
         LOSSES                                      Section 7.2
         NEOGENESIS                                  Recitals
         PHASE II CLINICAL TRIALS                    Section 4.3
         PHASE III CLINICAL TRIALS                   Section 4.3
         PRELIMINARY COMPOUND                        ATTACHMENT A
         PRIMARY ACTIVE COMPOUNDS                    ATTACHMENT A
         PRIMARY ENDPOINT                            Section 4.3
         PROGRAM TERM                                Section 8.1
         SCREENING PERIOD                            Section 2.4
         SCREENING PROGRAM                           C.F. PROGRAM and Section 2.4
         SELECTED SERIES                             ATTACHMENT A
         STEERING COMMITTEE                          Section 2.7
</Table>


2.  SCREENING PROGRAM; R&D PROGRAM; COMMERCIALIZATION

2.1 SCOPE. Aventis shall select [*] protein targets as Screening Targets for the
Program. Aventis will disclose proposed Screening Targets to NeoGenesis using
the procedure specified in Section 2.2; PROVIDED, that Aventis will complete all
proposed Screening Target disclosure for the [*] initial Screening Targets not
later than [*] following the Effective Date.

2.2 DISCLOSURE OF TARGETS. During the Program Term, Aventis shall from time to
time disclose additional Targets to NeoGenesis in writing. Within [*] of each
disclosure of a proposed Target by Aventis, NeoGenesis shall notify Aventis as
to whether such Target is an Excluded Target. If NeoGenesis does not serve such
notice within the specified period, such Target shall not be deemed to be an
Excluded Target. NeoGenesis may deem a Target as an Excluded Target if on the
date NeoGenesis receives such proposed Target disclosure from Aventis: (i)
NeoGenesis is contractually prohibited from performing the screening
contemplated in this Agreement on such proposed Target, (ii) NeoGenesis has
received a request from a third party to provide screening on such proposed
Target and NeoGenesis reasonably expects to commence screening within [*] for
such third party or (iii) NeoGenesis has previously conducted screening on such
proposed Target for another party (each, an EXCLUDED TARGET). NeoGenesis will
promptly notify Aventis if an Excluded Target that was excluded pursuant to
Section 2.2(ii) does not become the subject of screening at NeoGenesis within
said [*] period and Aventis may have such Excluded Target deemed a Screening
Target with notice to NeoGenesis.

2.3 DELIVERY OF TARGET PROTEINS. Aventis shall deliver the Screening Targets
that have been accepted by NeoGenesis to NeoGenesis for screening within [*]
following acceptance by NeoGenesis in accordance with Section 2.2. Aventis shall
provide Screening Targets in the quantities and formats specified in ATTACHMENT
A. Aventis shall also provide NeoGenesis at the time of delivery with a written
description of the concentration and volume of the Screening Target. Aventis
shall deliver the Screening Targets Ex Works to NeoGenesis' Cambridge facility.

2.4 SCREENING PROGRAM. (a) NeoGenesis will use its ALIS method to screen the
NeoMorph Library for activity with respect to each Screening Target for purposes
of identifying potentially useful chemical compounds for further

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evaluation and development. Screening will be performed pursuant to the
screening protocol for the Program set forth in ATTACHMENT A.

     (b) It is understood and agreed that while NeoGenesis will use Commercially
Reasonable efforts to complete the Screening Program for all three Screening
Targets within [*] following the Effective Date (the SCREENING PERIOD) and
complete the Hit Exploration Program for all [*] Screening Targets within [*]
following the Effective Date, in the event and to the extent that NeoGenesis has
not completed the Screening Program with respect to any Screening Target(s)
within such [*] period or completed the Hit Exploration Program within such [*]
period, NeoGenesis will continue to perform the applicable Program services
during the period following the expiration of the applicable period until
NeoGenesis completes the Program for each Screening Target submitted in
accordance with Sections 2.1-2.2 at no additional cost.

2.5 GRANT OF RESEARCH LICENSES. (a) Aventis hereby grants NeoGenesis a
nonexclusive, nontransferable, royalty-free license to use Aventis Intellectual
Property (including Aventis Patent Rights) solely for purposes of conducting the
Program and performing NeoGenesis' obligations under the Program. NeoGenesis
will not use Aventis Intellectual Property for any other purpose, without
Aventis' prior written permission. NeoGenesis shall not (i) grant, or attempt to
grant, a sub-license to use Aventis Intellectual Property to any Person without
the express written consent of Aventis, or (ii) modify the Screening Targets
supplied by Aventis, including, without limitation, the making of any analogs,
homologs or isomers thereof. In the event that NeoGenesis does not consume all
of the Screening Targets supplied by Aventis in performance of the Program,
NeoGenesis will upon completion of the Program, return to Aventis any quantities
of such Screening Target(s) and any analogs, homologs or isomers thereof.

     (b) NeoGenesis hereby grants Aventis a nonexclusive, nontransferable,
royalty-free license to use NeoGenesis Intellectual Property (including
NeoGenesis Patent Rights) solely for purposes of conducting the Program and
performing Aventis' obligations under the Program. Aventis will not use
NeoGenesis Intellectual Property for any other purpose, without NeoGenesis'
prior written permission. Aventis shall not grant, or attempt to grant, a
sub-license to use NeoGenesis Intellectual Property to any Person without the
express written consent of NeoGenesis. In addition, Aventis shall not analyze
any Preliminary Compounds or Active Compounds or Primary Active Compounds
structurally or otherwise seek to derive the structure of such Preliminary
Compounds or Active Compounds or Primary Active Compounds until such time as
Aventis designates Primary Active Compounds as Hit Compounds in accordance with
the procedure specified in ATTACHMENT A.

2.6 SCIENTIFIC REPORTS. (a) NeoGenesis will keep and maintain adequate records
containing laboratory data generated in the course of the Program to enable it
to furnish complete and accurate information to Aventis regarding the Program
activities and results, including all Preliminary Compounds, Active Compounds
and NeoMorph Focused Libraries identified in the Program and all NeoGenesis
Program Intellectual Property developed during the Program. All such written
records of NeoGenesis shall be open to inspection by Aventis during normal
business hours upon reasonable prior notice.

     (b) NeoGenesis shall provide Aventis with reasonably-detailed written
reports describing the results of the research performed pursuant to the Program
including all Preliminary Compounds, Active Compounds and NeoMorph Focused
Libraries identified in the Program. Such reports shall be delivered to Aventis
at least monthly during the Program. NeoGenesis will deliver a Final Target
Report and a Candidate Lead Compound Report (as defined in ATTACHMENT A) with
respect to the Program work performed on each Screening Target including a
description of all the Preliminary Compounds, Primary Active Compounds and
NeoMorph Focused Libraries identified during the Program with respect to such
Screening Target.

2.7 STEERING COMMITTEE. (a) A Steering Committee (STEERING COMMITTEE) shall be
responsible for the oversight of the day-to-day management of the Program. The
Steering Committee shall consist of four members, two members to be appointed by
each of NeoGenesis and Aventis. Each party may, with notice to the other,
substitute any of its members serving on the Steering Committee. The initial
Aventis members shall be John Hodgson and Norbert Dereu and the initial
NeoGenesis members shall be Peter Lomedico and Huw Nash. Aventis shall have the
right to appoint one of its members to be the chairperson of the Steering
Committee.

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     (b) The Steering Committee shall be responsible for the management and
conduct of the Program and shall in particular: (i) consider, review and amend
the Program from time to time in such manner as may be appropriate; (ii) monitor
progress of the Program; (iii) report regularly to the management of both
parties upon the progress of the Program; and (iv) be the initial medium for
transfer of information between the parties.

     (c) The Steering Committee shall hold meetings as mutually agreed by the
parties (but in no event less than four (4) times during the Screening Period)
to review the Program. The first meeting of the Steering Committee shall be held
within forty-five (45) days of the Effective Date and shall be held in
Cambridge, MA. Thereafter, meetings may be held by telephone or video conference
if requested by either party in writing to the other, PROVIDED that the parties
shall meet in person at least two (2) times during the Screening Period. Draft
Minutes of all meetings setting forth decisions of the Steering Committee
relative to the Screening Process shall be prepared by the Chairman, or his
designate and circulated by the Chairman to both parties within fifteen (15)
days after each meeting, but minutes shall not become official until approved by
both parties (which approval the parties shall use reasonable efforts to give
within thirty (30) days of receipt of such minutes).

     (d) The quorum for Steering Committee meetings shall be two, provided there
is at least one member from each of NeoGenesis and Aventis present. Aventis and
NeoGenesis shall each have one vote at the Steering Committee. The Steering
Committee will render decisions by unanimous vote. Disagreements among the
Steering Committee regarding the Program will be resolved via good-faith
discussions; PROVIDED, that in the event of a disagreement that cannot be
resolved within fifteen (15) days after the date on which the disagreement
arose, the matter shall be referred to Aventis' Head of Drug Innovation and
Approval for France and NeoGenesis' Chief Executive Officer or their respective
designees. Thereafter, if any such disagreement is not resolved within thirty
(30) days, then Aventis will have the right to make the final decision.

2.8 LEAD COMPOUNDS. (a) Within [*] following the completion of the evaluation
described in Paragraph 8 of ATTACHMENT A, the Steering Committee shall make a
recommendation to Aventis on the nomination of Lead Compounds. Within [*] from
receipt of the Steering Committee's recommendation, Aventis shall notify
NeoGenesis whether it will designate any Lead Compounds for such Screening
Target, or whether it wishes further optimization work with respect to such
Selected Series. If Aventis does not designate any Lead Compound(s) against a
particular Screening Target within such period or initiate further optimization
work with respect to such Selected Series within such period, the rights granted
Aventis shall terminate and be of no further force or effect with respect to
Lead Compounds and/or Products against the applicable Screening Target, and no
further payment from Aventis shall be due with respect to such Screening Target.
If Aventis does identify any Lead Compounds, such Lead Compounds will be subject
to the license granted Aventis and shall no longer be available to NeoGenesis or
any third party in any NeoGenesis compound library, including its mass encoded
NeoMorph compound library or in any other manner. There shall be no limit on the
number of Lead Compounds that may be taken; PROVIDED, all such Lead Compounds
have a binding affinity of [*] and demonstrated activity in the Screening
Target-based biochemical/functional assays with [*]. If Aventis does not
identify any Lead Compounds but does initiate further optimization work with
respect to such Selected Series, such Selected Series compounds will remain
subject to Section 3.2 and Section 3.3(a) for a period of not longer than [*]
during which optimization may be performed and Aventis will pay NeoGenesis in
accordance with Section 4.2 as if the Hit Exploration Program were being
pursued. If Aventis does not designate Lead Compounds by the end of such [*]
period, Aventis will be deemed to have not designated Lead Compounds in respect
of such Screening Target.

     (b) Within thirty (30) days following receipt of notification from Aventis
identifying Lead Compounds, NeoGenesis shall amend ATTACHMENT D to identify any
applicable NeoGenesis Patent Rights not previously identified to Aventis.

2.9 PRODUCT DEVELOPMENT. Aventis, at its sole expense, shall be responsible for
and shall use its Commercially Reasonable Efforts to conduct the R&D Program
related to Lead Compounds and Products and to develop and obtain Regulatory
Approvals for Products in each of the Major Countries; provided that, in the
reasonable exercise of Aventis discretion, development in each such Major
Country is commercially expedient.

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2.10 MANUFACTURE OF PRODUCT. Aventis, at its sole expense, shall be responsible
for and shall use its Commercially Reasonable Efforts to Manufacture the
Products in accordance with the Regulatory Approvals, Applicable Laws, Good
Laboratory Practices and Good Manufacturing Practices.

2.11 REGULATORY MATTERS. Aventis, at its sole expense, shall be responsible for
the preparation and filing, with the appropriate Regulatory Authorities, of all
documents that are necessary to conduct clinical studies of Products and
Regulatory Approval applications that are necessary to market and sell Products.
Aventis shall use Commercially Reasonable Efforts to file Regulatory Approval
applications in the Major Countries. Simultaneously with the submission of each
such regulatory filing, Aventis shall notify NeoGenesis, in writing, that such
regulatory filing has been made. Aventis shall be responsible for reporting all
adverse events associated with any Product to the appropriate Regulatory
Authorities in accordance with Applicable Laws.

2.12 MARKETING AND SALE. Aventis, at its sole expense, shall be responsible for
the Commercialization of Products in the Territory and shall use its
Commercially Reasonable Efforts to Commercialize each Product in each of the
Major Countries. Aventis shall be responsible for establishing the price of each
Product sold by or on behalf of it pursuant to this Agreement.

2.13 THIRD PARTY LICENSES. Aventis, at its sole expense, shall be responsible
for obtaining any and all licenses from third parties necessary or desirable to
perform the R&D Program and/or to Commercialize any Product; PROVIDED, that the
provisions of Section 4.4(b) may result in a reduction in the royalties payable
to NeoGenesis with respect to certain third party licenses.

2.14 COMPLIANCE WITH LAW. Aventis shall conduct the R&D Program and conduct its
Manufacturing operations in a safe and prudent manner, in compliance with all
Applicable Laws (including, but not limited to, occupational safety and health,
public safety and health, protecting the environment, the disposal of wastes,
Good Clinical Practices, Good Laboratory Practices and Good Manufacturing
Practices), and in compliance with all applicable provisions of this Agreement.
Aventis shall obtain all necessary registrations and permits pertaining to
activities contemplated by this Agreement. NeoGenesis shall conduct all
activities contemplated by this Agreement in accordance with all Applicable
Laws, including, but not limited to, occupational safety and health, public
safety and health, protecting the environment, the disposal of wastes and Good
Laboratory Practices.

2.15 PERIODIC REVIEW. Aventis and NeoGenesis shall periodically meet, at such
times and places as are mutually agreed upon, for Aventis to provide NeoGenesis
with an update on the status of the progress of Aventis' R&D Program and
Commercialization of each Product, PROVIDED, HOWEVER, that such meetings shall
occur no more than twice per calendar year unless the parties agree, in writing,
to meet more often. Aventis and NeoGenesis shall each be responsible for its own
expenses incurred in connection with attending such meetings.


3.  LICENSE; PROPRIETARY RIGHTS

3.1 GRANT OF LICENSE. (a) Subject to the terms and conditions of this Agreement,
including the payment of all applicable fees, NeoGenesis hereby grants to
Aventis, and Aventis hereby accepts, an exclusive, worldwide, right and license,
within the Territory, to use the NeoGenesis Intellectual Property and NeoGenesis
Patent Rights with application to the Field (collectively, the LICENSED
TECHNOLOGY) to the extent necessary or useful to research, develop, make, have
made, use, distribute for sale, promote, market, offer for sale, sell, have
sold, import and export Lead Compounds and Products. Aventis may grant
sublicenses of its rights under this Section 3.1; PROVIDED that Aventis: (i)
obtains the written agreement of each non-Affiliated sublicensee to be subject
to the same obligations as is Aventis under Sections 2.14, 2.15, 3.1(c), 3.2,
4.4-4.8, 5.2 and 8.3(c) (last sentence) of this Agreement (or substantially
identical provisions) and (ii) shall remain responsible for the performance of
all of its obligations under this Agreement, whether such obligations are
performed by Aventis, its Affiliates or any of its sublicensees. Aventis shall
also ensure that all sublicensees are required to indemnify NeoGenesis with
respect to the matters that are addressed in Section 7.2(b) and Section 7.3(b)
(it being further understood that NeoGenesis need not be identified by name).

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     (b) The license granted under this Section 3.1 shall be treated as a
license of rights to "intellectual property" (as defined in Section 101(56) of
Title 11 of the United States Code, as amended (the BANKRUPTCY CODE)) for
purposes of Section 365(n) of the Bankruptcy Code. The parties agree that
Aventis may elect to retain and may fully exercise all of its rights and
elections under the Bankruptcy Code PROVIDED, that it abides by the terms of
this Agreement.

     (c) Aventis shall mark or have marked all containers or packages of
Products that are the subject of the license granted under this Section 3.1 in
accordance with the patent marking laws of the jurisdiction in which such
Products are manufactured, used or sold.

3.2 RETAINED RIGHTS. (a) This Agreement does not convey to NeoGenesis any
ownership rights in any Aventis Intellectual Property by implication, estoppel
or otherwise except for the rights expressly granted in Section 2.5. Title to
the Aventis Intellectual Property shall at all times remain vested in Aventis.
This Agreement does not convey to Aventis any ownership rights in any NeoGenesis
Intellectual Property by implication, estoppel or otherwise except for the
rights expressly granted in Section 3.1 and assigned in Section 3.2(d). Title to
the NeoGenesis Intellectual Property shall at all times remain vested in
NeoGenesis. Title to and any interest in Program Intellectual Property described
in clause (a) of the Program Intellectual Property definition (including
corresponding Program Patent Rights) shall be the property of NeoGenesis and is
included in the definition of NeoGenesis Intellectual Property. Title to and any
interest in Program Intellectual Property described in clause (b) of the Program
Intellectual Property definition (including corresponding Program Patent Rights)
shall be jointly held by Aventis and NeoGenesis. Title to and any interest in
Program Intellectual Property described in clause (c) of the Program
Intellectual Property definition (including corresponding Program Patent Rights)
shall be the property of Aventis and is included in the definition of Aventis
Intellectual Property. Notwithstanding any of the foregoing, Program
Intellectual Property, regardless of inventorship, shall be: (i) the property of
NeoGenesis if such Program Intellectual Property is directly related to the
NeoMorph Screening Library (except as described in Section 3.2(a)(ii)(2) below),
ALIS screening technology or QSCD; and (ii) the property of Aventis (1) if such
Program Intellectual Property is directly related to the Screening Targets or
the uses thereof or to Aventis' functional or secondary assays, or to the
Products, or (2) if such Program Intellectual Property relates to the Lead
Compounds and analogs, homologs and isomers thereof or the Products.

     (b) If required, patent counsel mutually acceptable to the parties and
selected by the Steering Committee in accordance with Section 3.3(c) shall
determine inventorship of all Program Intellectual Property (including Program
Patent Rights) that arises from the transactions contemplated by this Agreement
in accordance with U.S. patent law (and other U.S. intellectual property law)
when determining whether such intellectual property is (i) Aventis Intellectual
Property or (ii) NeoGenesis Intellectual Property or (iii) whether Program
Intellectual Property (including Program Patent Rights) is jointly owned or is
owned solely by NeoGenesis or owned solely by Aventis.

     (c) NeoGenesis shall retain the following rights with respect to the
following NeoGenesis Intellectual Property and Program Intellectual Property
(including Program Patent Rights):

         (i) NeoGenesis shall continue to use its NeoMorph Screening Library to
         screen target proteins for other parties; PROVIDED, that any Screening
         Targets screened by NeoGenesis on behalf of Aventis, shall not be
         screened for a third party or internally at NeoGenesis (nor shall
         NeoGenesis research, develop, make, use or sell any products active
         against such Screening Targets) during the Program and for a period of
         [*] following the completion of all work by NeoGenesis under the
         Program. It is understood and acknowledged by NeoGenesis that the
         restrictions imposed by this paragraph will operate independently of
         and in addition to any patent rights that Aventis may hold in respect
         of any Screening Target.

         (ii) NeoGenesis shall retain all rights and may continue to use
         Preliminary Compounds created as part of the Program but not selected
         as Primary Active Compounds and Primary Active Compounds not selected
         as Hit Compounds; PROVIDED, HOWEVER, that such Preliminary Compounds
         and Primary Active Compounds (A) may not be used against the Screening
         Targets and (B) shall only be used in the event and to the extent they
         result from use of the primary mass-encoded NeoMorph Screening Library
         to screen target proteins for other parties. Notwithstanding the
         foregoing, it is understood and agreed that NeoGenesis shall mask all
         Preliminary Compounds created as part of the Program until such time as
         Aventis selects Primary Active

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         Compounds in accordance with paragraph 3 of ATTACHMENT A and shall
         mask all Primary Active Compounds created as part of the Program until
         such time as Aventis selects Hit Compounds in accordance with
         paragraph 6 of ATTACHMENT A and shall mask all Hit Compounds created
         as part of the Program until such time as Aventis selects Lead
         Compounds in accordance with Section 2.8.

     (d) In addition to the license granted under Section 3.1 with respect to
Licensed Technology, NeoGenesis hereby assigns and agrees to assign to Aventis
all of NeoGenesis' right, title and interest in all Lead Compounds designated by
Aventis in accordance with Section 2.8. Such assigned Lead Compounds and the
corresponding NeoGenesis Patent Rights shall, from the date of assignment by
NeoGenesis, be treated as Aventis Patent Rights for purposes of this Agreement
(including Section 3.3(c) and Section 3.4) and such assigned Lead Compounds and
the corresponding NeoGenesis Intellectual Property shall, from the date of
assignment by NeoGenesis, be treated as Aventis Intellectual Property for
purposes of this Agreement (including Section 3.3(c) and Section 3.4); PROVIDED,
that notwithstanding any provision of this Agreement to the contrary, Aventis
shall remain obligated to pay NeoGenesis in respect of all such assigned Lead
Compounds (and any related Products) the milestone fees and royalties due
NeoGenesis under Section 4.3 and Section 4.4 of this Agreement. The date of
assignment with respect to the designated Compounds shall be the date Aventis
notifies NeoGenesis that a particular Hit Compound has been designated as a Lead
Compound and pays the fee for such Lead Compound specified in Section 4.3(a)(i).

     (e) If, at any time during the applicable license term, NeoGenesis has or
obtains any patent or other proprietary right in any Program Intellectual
Property (by ownership or license) that could be asserted to prevent Aventis
from practicing the Aventis Intellectual Property or Program Intellectual
Property owned by Aventis to research, develop, make and have made, use,
distribute for sale, promote, market, offer for sale, sell, have sold, import
and export compounds, NeoGenesis will grant Aventis a non-exclusive, worldwide,
perpetual license (or sublicense, as the case may be), with the right to
sublicense, to such patent or other proprietary right and Aventis will pay
NeoGenesis royalties on sales of such compounds as described under Section 4.4
to the extent necessary or useful to practice the license granted under Section
3.1; provided, however, that the foregoing shall not be construed to grant
Aventis any license to utilize NeoGenesis' proprietary mass encoded NeoMorph
compound library, ALIS screening technology or QSCD except as otherwise
expressly set forth in this Agreement.

     (f) Aventis hereby grants NeoGenesis an irrevocable, exclusive (except as
to Aventis as described below in this Section 3.2(f)), fully-paid, perpetual
license to any Program Intellectual Property described in Section 3.2(a)(ii)(2),
except that in each case Aventis will retain exclusive rights in such Program
Intellectual Property (the GENERIC RIGHTS) to the extent necessary or useful to
research, develop, make and have made, use, distribute for sale, promote,
market, offer for sale, sell, have sold, import and export Lead Compounds and/or
Products.

     (g) Neither party shall use Program Intellectual Property owned by the
other party unless exclusively licensed back to such party by the other party
(pursuant to Section 3.2(f)) or Confidential Information of the other party
outside of the performance of the Program or except as otherwise permitted in
the Agreement.

3.3 DISCLOSURE; PATENT PROSECUTION. (a) Each of NeoGenesis and Aventis shall
promptly disclose to the other knowledge of any Invention that constitutes
Program Intellectual Property; such Program Intellectual Property will be added
to ATTACHMENT B (and ATTACHMENT D if applicable) and will be subject to the
provisions of this Agreement. Within forty-five (45) days following the date of
such disclosure regarding the existence of particular Program Intellectual
Property that is jointly owned, the parties shall confer as to appropriate
protection for such Program Intellectual Property. Notwithstanding the provision
of this Section 3.3, no party shall file, prosecute and maintain any Program
Patent Right without the other party's prior written consent before the date
specified in Section 2.8 for Aventis' notice of Lead Compounds.

(b) NeoGenesis shall have the sole right, but not the obligation, to file,
prosecute, and maintain, at NeoGenesis' sole expense, each of the NeoGenesis
Patent Rights throughout the Territory. NeoGenesis shall promptly furnish or
have furnished to Aventis copies of all patents, patent applications,
substantive patent office actions, substantive responses received or filed in
connection with such patents and patent applications (other than patents and
patent applications covering solely NeoGenesis Intellectual Property that is not
licensed to Aventis under Section 3.1 or assigned to Aventis under Section
3.2(d)). Aventis may itself or through its attorney offer comments and
suggestions with

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respect to the matters that are the subject of this Section 3.3(b) and
NeoGenesis agrees to consider such comments and suggestions; PROVIDED that
nothing herein shall obligate NeoGenesis to adopt or follow such comments or
suggestions. Aventis shall cooperate in the preparation, filing, prosecution and
maintenance of any and all patent applications and patents included in Program
Intellectual Property owned by NeoGenesis. NeoGenesis shall promptly provide
notice to Aventis as to all matters that come to its attention that may affect
the preparation, filing, prosecution or maintenance of any patents or patent
applications within the Program Intellectual Property owned by NeoGenesis.
NeoGenesis shall not seek patent protection that covers generic claims to any
class of compounds developed in the course of the Program until such time as
Aventis has designated Lead Compounds in respect of such class of compounds or
until the period of time for such designation expires with respect to the
Selected Compounds derived from such class of compounds. In the event that
NeoGenesis elects not to file for patent protection under the NeoGenesis Patent
Rights or elects not to prosecute or maintain a patent or patent application
under the NeoGenesis Patent Rights it shall notify Aventis of such decision at
least forty-five (45) days prior to the due date of any action or payment due.
Aventis shall have the right, but not the obligation to assume the
responsibility therefor then at its own cost and expense. If appropriate, such
patents and patent applications rights should then be assigned to Aventis;
PROVIDED, Aventis reimburses NeoGenesis for its' documented patent costs in
respect of such assigned patents and patent applications.

(c) Aventis shall have the sole right, but not the obligation, to file,
prosecute, and maintain, at Aventis' sole expense (except as provided below),
each of the Aventis Patent Rights throughout the Territory. Aventis shall
promptly furnish or have furnished to NeoGenesis copies of documents relevant to
Generic Rights and provide NeoGenesis with the opportunity to review and comment
on patent decisions made by patent counsel. NeoGenesis shall be responsible for
[*] of all costs relating to the preparation, filing, prosecution and
maintenance of any and all patent applications and patents covering Generic
Rights. NeoGenesis shall cooperate in the preparation, filing, prosecution and
maintenance of any and all patent applications and patents included in Program
Intellectual Property owned by Aventis. Aventis shall promptly provide notice to
NeoGenesis as to all matters that come to its attention that may affect the
preparation, filing, prosecution or maintenance of any patents or patent
applications within the Program Intellectual Property owned by Aventis relating
to Generic Rights.

3.4 ENFORCEMENT. (a) NeoGenesis shall be solely responsible for defense and
enforcement of NeoGenesis Intellectual Property and NeoGenesis Patent Rights but
excluding Licensed Technology. Aventis shall be solely responsible for the
defense and enforcement of Aventis Intellectual Property and Aventis Patent
Rights.

     (b) Except as otherwise provided in Section 3.4(a), Aventis shall have the
first option to pursue any enforcement or defense of Licensed Technology;
PROVIDED, that Aventis pays all costs and expenses related to the same, keeps
NeoGenesis reasonably informed of its progress and provides NeoGenesis with
copies of any documents related to such proceedings and reasonable notice of all
proceedings relating to same. Aventis' costs in prosecuting such matters shall
be subject to reimbursement in accordance with Section 3.4(d). Aventis shall
notify NeoGenesis of its decision to exercise its right to enforce Licensed
Technology as soon as possible, and shall bring an enforcement action not later
than sixty (60) days (forty five (45) days in the case of an action brought
under the Hatch-Waxman Act) following its discovery or receipt of notice of the
alleged infringement.

     (c) If Aventis does not exercise its option to enforce or defend any
Licensed Technology within sixty (60) days (forty five (45) days in the case of
an action brought under the Hatch-Waxman Act) or (within ninety (90) days of
commencing to prosecute any enforcement or defense action) Aventis and
NeoGenesis have not otherwise agreed not to pursue such infringement for
business reasons, and Aventis (i) has not persuaded the alleged infringer to
desist, (ii) is not diligently pursuing an infringement action or diligently
defending the validity or enforceability of Licensed Technology at issue, as
determined by NeoGenesis in its reasonable discretion, or (iii) has not provided
NeoGenesis with evidence of bona fide negotiations of an acceptable sublicense
agreement with the alleged infringer, then NeoGenesis shall have the right to
pursue the alleged infringer or take control of any action initiated by Aventis
at NeoGenesis' own expense. In any such case, Aventis will substitute NeoGenesis
as party plaintiff for purposes of pursuing any alleged infringer.

     (d) Any recovery of damages with regard to Licensed Technology in any suit
handled by one party pursuant to Section 3.4(b) or Section 3.4(c) shall be
applied first in satisfaction of any unreimbursed expenses and legal fees of

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the litigant relating to the suit or settlement thereof. The balance of any
recovery shall be distributed (i) first to Aventis in an amount equal to its
lost profits or a reasonable royalty on the sales of the infringer (whichever
measure of damages the court shall have applied), and (ii) then to NeoGenesis in
an amount equal to the royalties due NeoGenesis based on such sales (if the
court applies a sales of the infringer measure of damages) or a reasonable
approximation of the royalties that Aventis would have owed to NeoGenesis on
sales of Products that Aventis lost to the infringer (if the court applies a
lost profits measure of damages). The balance, if any, remaining after Aventis
has been compensated for lost profits or lost sales and NeoGenesis has been
compensated for lost royalties shall be paid to Aventis. No settlement, or
consent judgment or other voluntary final disposition of any suit regarding
Licensed Technology may be entered into without the consent of the other party,
which consent shall not be unreasonably withheld.

     (e) Notwithstanding the provisions of Section 3.4(b), in the event that a
declaratory judgment action alleging invalidity or non-infringement of any of
the patents within Licensed Technology that are within NeoGenesis Patent Rights
but are not within jointly owned Program Intellectual Property, NeoGenesis shall
have the first option, within sixty (60) days after notification of same, to
assume defense of the action concerning its own technology at its expense, but
Aventis shall be entitled to participate in such action, at its own expense.

     (f) In any infringement suit as either party may institute to enforce
Licensed Technology, or in any declaratory judgment action alleging invalidity
or non-infringement of any Licensed Technology brought against NeoGenesis or
Aventis, the other party shall, at the request and expense of the party
initiating or defending the suit or action, cooperate and assist in all
reasonable respects, having its employees testify when requested and making
available relevant records, papers, information, specimens and the like.


4.  PRICING; PAYMENT

4.1 SCREENING FEE. Aventis shall pay NeoGenesis a fee of [*] for each Screening
Target screened pursuant to the Program that is a non-protein/protein
interaction Screening Target and a fee of [*] for each Screening Target screened
pursuant to the Program that is a protein/protein interaction Screening Target.
Such fee shall be payable with respect to the first [*] Screening Targets in two
installments: the first installment of [*] on the Effective Date and the second
installment consisting of the remaining balance due in accordance with the
immediately preceding sentence within [*] of "completion of screening" against
all [*] of the Screening Targets. "Completion of screening" for each Screening
Target shall be deemed to occur upon delivery of Hit Compounds for such
Screening Target to Aventis (or, if Aventis does not designate any Hit
Compound(s) for such Screening Target, within [*] of receipt of the Final Target
Report for such Screening Target, then at the end of such [*] period). Any work
conducted for further optimization and evaluation of Hit Compounds to Selected
Series or to Lead Compounds will be carried out on FTE basis in accordance with
Section 4.2 and Paragraphs 7-8 of ATTACHMENT A.

4.2 HIT EXPLORATION FEE. Commencing on the first anniversary of the Effective
Date, but not prior to the date Aventis commences optimization of Hit Compounds
resulting from the Screening Program (whether such optimization is performed by
NeoGenesis or Aventis), Aventis will provide NeoGenesis with [*] of funding, at
the FTE Rate and payable in equal quarterly installments over such [*], for at
least [*] full time FTE positions per year to facilitate the performance by
NeoGenesis of the Hit Exploration Program. Aventis may increase such Hit
Exploration Program funding for up to an aggregate [*] FTE positions per annum.
Such FTE personnel shall, at the direction of the Steering Committee, perform
optimization and evaluation of Hit Compounds to Selected Series or to Lead
Compounds; PROVIDED, that if the Steering Committee does not direct the
expenditure of all FTE funding on such optimization and evaluation services in
any year of such [*] period, Aventis may use such FTE funding to fund screening
of up to [*] additional Screening Target during each year of such [*] period;
such additional Screening target to be proposed by Aventis using the procedure
specified in Section 2.2.

4.3 MILESTONES. (a) Aventis will pay NeoGenesis milestone payments in respect of
Products as specified in this Section 4.3.

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         (i)  Within thirty (30) days following the date on which Aventis
              identifies each Lead Compound (if any), Aventis will pay
              NeoGenesis [*]. Aventis shall promptly notify NeoGenesis of the
              decision to nominate a Lead Compound.

         (ii) Within thirty (30) days following the date on which Aventis files
              the first IND in a Major Country, Aventis will pay NeoGenesis [*].
              Aventis shall promptly notify NeoGenesis of the decision to
              initiate such toxicology studies.

         (iii)Within thirty (30) days following the date on which the first
              administration or dosing of any Product occurs in a Major Country
              in the first Phase II Clinical Trials relating to such Product,
              Aventis will pay NeoGenesis [*]. PHASE II CLINICAL TRIALS means
              any human clinical trials for which a Primary Endpoint is a
              preliminary determination of safety, biological activity, efficacy
              or dose ranges in patients with the disease target being studied
              as required by the relevant Regulatory Authorities. PRIMARY
              ENDPOINT means, with respect to a Phase II Clinical Trial, the
              point at which POSITIVE statistical significance has been achieved
              with respect to the primary endpoint specified in the protocol for
              such trial.

         (iv) Within thirty (30) days following the date on which the first
              administration or dosing of any Product occurs in a Major Country
              in the first Phase III Clinical Trials relating to such Product,
              Aventis will pay NeoGenesis [*]. PHASE III CLINICAL TRIALS means
              any clinical studies of any Product in human patients with the
              disease target being studied to determine safety and efficacy of a
              Product in patients as required by the relevant Regulatory
              Authorities.

         (v)  Within thirty (30) days following the date on which Aventis
              receives an NDA approval from the FDA permitting the manufacture
              and sale of a Product, or a comparable Regulatory Approval for
              another Major Country, Aventis will pay NeoGenesis [*].

     (b) Milestones identified in Section 4.3(a)(i)-(v) shall be due only for
the first Product that is active against a particular Screening Target,
regardless of (i) the number of Products that are active against such Screening
Target that are identified by the Program or developed and/or commercialized by
Aventis, and (ii) the number of times a Product hits such milestone (e.g., if
different indications are pursued for the same Product); PROVIDED, that if the
first Product that is active against a Screening Target does not achieve any
milestone(s), such non-achieved milestones shall be paid on any subsequent
Product that is active against such Screening Target and that achieves such
milestone. On the date any one milestone with respect to a Product is achieved,
all lower numbered unachieved milestones shall be deemed to have been achieved
with respect to that Product and shall be paid (except to the extent they have
previously been paid with respect to another Product active against the relevant
Screening Target).

4.4 ROYALTIES. (a) Not later than [*] following each March 31, June 30,
September 30 and December 31 commencing with the First Commercial Sale of
Products that are active against Screening Targets in any country, Aventis shall
pay to NeoGenesis royalties by country for the most recent three-month period
then ended, equal to (i) [*] of Net Sales. Aventis shall pay royalties with
respect to each Product on a country by country basis (1) until the expiration
or revocation or complete rejection of the last to expire or to be revoked or to
be completely rejected of any NeoGenesis Patent Right (including those
NeoGenesis Patent Rights assigned to Aventis pursuant to Section 3.2(d))
covering such Product in the country in which the Product is manufactured or
sold, or (2) if no NeoGenesis Patent Right (including those NeoGenesis Patent
Rights assigned to Aventis pursuant to Section 3.2(d)) exists in the relevant
country covering the manufacture, use or sale of the relevant Product, until [*]
from the First Commercial Sale of such Product in such country.

     (b) If Aventis is required to make payments (including, without limitation,
royalties, option fees or license fees) to one or more third parties to obtain
licenses or similar rights under patents owned by a third party to avoid
infringement by any Product of such third party(ies) patent-protected
technology, then Aventis may, beginning from the date of such third party
payments, deduct fifty percent (50%) of the amount of such third party payments
in any calendar quarter from the royalties payable to NeoGenesis in such
calendar quarter; provided that such deductions

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       14
<Page>

shall not exceed one half (50%) of the applicable royalty rate specified in
Section 4.4(a) with respect to such Product.

4.5 REMITTANCE. (a) All royalties and milestone payments required under this
Section 4 shall be payable in full in the United States in United States
Dollars, regardless of the countries in which sales are made. For the purpose of
computing Net Sales for which a currency other than United States Dollars is
received, such currency shall be converted into United States Dollars at the
simple average of the closing mid-point rates for the last business day of each
month of the calendar quarter for buying United States Dollars for the calendar
quarter in which such sales were made. The "closing mid-point rates" found in
the "Dollar spot forward against the Dollar" table published by THE FINANCIAL
TIMES or any other publication as agreed to by the parties shall be used as the
source of spot rates to calculate the average as defined in the preceding
sentence.

     (b) In the event that any payment due NeoGenesis under this Agreement is
not made when due, the amount due shall accrue interest beginning on the fifth
day following the final date on which such payment was due, calculated at the
annual rate equal to two percent (2%) above the 30-day LIBOR for U.S. dollars
reported in the WALL STREET JOURNAL for the due date, calculated from the due
date until paid in full. Such payment when made shall be accompanied by all
interest so accrued. Said interest and the payment and acceptance thereof shall
not negate or waive the right of NeoGenesis to any other remedy, legal or
equitable, to which it may be entitled because of the delinquency of the
payment.

     (c) If at any time legal restrictions within any country in the Territory
prevent the conversion of the local currency and such currency cannot be removed
from such country such that prompt remittance by Aventis of any royalties owed
by Aventis to NeoGenesis in respect of sales in such country is prevented,
Aventis shall make payment through any lawful means or methods that may be
available as Aventis shall reasonably determine. If royalties in any country
cannot be remitted within three (3) months after the end of the relevant royalty
period then Aventis shall pay NeoGenesis in the local currency of such country
by deposit of the relevant royalties in a bank account in such country
designated by NeoGenesis.

4.6 RECORDS. Aventis, its Affiliates and sublicensees shall keep and maintain
for a period of at least three (3) years from the date of each payment of
royalties, records (prepared in accordance with GAAP) sufficient to determine
the amounts of Net Sales and payments due under Section 4.4. Within forty-five
(45) days following each March 31, June 30, September 30 and December 31 in
which payments are due under Section 4.4, Aventis shall provide NeoGenesis with
a report including at least: (a) actual Net Sales, by country in local currency;
(b) the currency conversion rate used and U.S. dollar-equivalent of such sales;
(c) the calculation of royalties thereon; and (d) the total royalties so
computed and due NeoGenesis. Such reports shall be submitted to NeoGenesis
whether or not any sales of Product have been made during such period. Upon
delivery of the report due for the period ending December 31 of each year,
Aventis shall also report to NeoGenesis the aggregate royalties due NeoGenesis
for the entire preceding year.

4.7 INSPECTION. Aventis and its Affiliates shall, and Aventis shall provide in
any agreements with any sublicensees that such sublicensees shall, each make its
records available for inspection by an independent certified public accountant,
appointed by NeoGenesis and reasonably acceptable to Aventis, during regular
business hours at such place or places where such records are customarily kept,
upon reasonable notice from NeoGenesis, to verify the accuracy of the reports
and payments. Such inspection right shall not be exercised more than once in any
calendar year nor more than once with respect to sales of Products in any given
payment period. NeoGenesis agrees to hold in confidence all information
concerning royalty payments and reports, and all information learned in the
course of any audit or inspection, except to the extent necessary for NeoGenesis
to reveal such information in order to enforce its rights under this Agreement
or if disclosure is required by law, regulation or judicial order. Any person or
entity conducting such audit or inspection will agree in writing with NeoGenesis
to treat all records reviewed in the course of the audit or inspection as the
Confidential Information of Aventis under terms and conditions no less
restrictive than the terms contained in Section 5.2. The results of each
inspection, if any, shall be binding on both parties. NeoGenesis shall pay for
such inspections, except that in the event there is any upward adjustment in
aggregate royalties payable for any year shown by such inspection of more than
five percent (5%) of the total amount paid during the period that is the subject
of the inspection, Aventis shall pay for such inspection.

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       15
<Page>

4.8 TAXES. If at any time, any jurisdiction within the Territory requires the
withholding of income taxes or other taxes imposed upon payments set forth in
this Section 4, Aventis shall make such withholding payments as required and
subtract such withholding payments from the payments to be made to NeoGenesis as
set forth in this Section 4, or if applicable, NeoGenesis will reimburse Aventis
or its designee(s) of the amount of such withholding payments that are not
subtracted from the payments made to NeoGenesis as set forth in this Section 4.
Aventis shall provide NeoGenesis with documentation of such withholding and
payment in a manner that is satisfactory for purposes of reporting to the U.S.
Internal Revenue Service. Any withholdings paid when due hereunder shall be for
the account of NeoGenesis. Withholding payments made by Aventis pursuant to this
Section 4.8 shall be made based upon financial information provided to Aventis
by NeoGenesis, and to the extent that such information is incorrect, NeoGenesis
shall be liable for any deficiency, and any fine, assessment or penalty imposed
by any taxing authority in the Territory for any deficiency in the amount of any
such withholding or the failure to make such withholding payment. If Aventis is
required to pay any such deficiency, or any fine, assessment or penalty for any
such deficiency, NeoGenesis shall promptly reimburse Aventis for such payments.
The parties will cooperate to minimize, to the extent legally permissible, the
tax liabilities related to this Agreement. Notwithstanding the foregoing, such
cooperation shall not cause any adverse tax consequences to be incurred by
either party which would not have been incurred under the provisions of this
Agreement, including this Section 4.8. No U.S. sales tax or similar taxes will
be due by Aventis on any of the contractual payments set forth in this Section
4.

4.9 INVOICES. All payments will be made thirty (30) days after receipt of an
invoice in the name of Aventis Pharma S.A and sent to the following address:

     Aventis Pharma S.A.
     Comptabilite Fournisseurs
     Tri 403
     20, avenue Raymond Aron
     F-92160 ANTONY

     The invoice should mention: "Dossier gere par N. Delbos"


5.  CONFIDENTIALITY

5.1 PUBLICITY. Except as is necessary to enforce their respective rights under
this Agreement, or to a party's legal or financial advisors, and except as
otherwise agreed to by the parties in writing, the parties shall: (a) keep the
material terms of this Agreement confidential; and (b) agree upon the text and
the exact timing of an initial public announcement relating to the transactions
contemplated by this Agreement as soon as practicable after the Effective Date
(such agreement not to be unreasonably withheld or delayed). Each party may
thereafter disclose to third parties the specific information contained in such
public announcement without the need for further approval by the other party.
Nothing in this Section 5.1 shall prohibit a party from making such disclosures
to the extent required under applicable federal or state securities laws or any
rule or regulation of any nationally recognized securities exchange. In such
event, however, the disclosing party shall use good faith efforts to notify and
consult with the other party prior to such disclosure and, where applicable,
shall diligently seek confidential treatment to the extent such treatment is
available under applicable securities laws.

5.2 CONFIDENTIALITY. (a) Confidential Information of each party will be used by
the other party solely for the purposes permitted by this Agreement. All
Confidential Information will be received and held in confidence by the
receiving party, subject to the provisions of this Agreement. Each party
acknowledges that it will not obtain any rights of any sort in or to the
Confidential Information of the other party as a result of such disclosure and
that any such rights must be the subject of separate written agreement(s).
Either party may only disclose the general nature, but not the specific
financial terms, of this Agreement without the prior consent of the other party;
PROVIDED that either party may provide a copy of this Agreement or disclose the
terms of this Agreement (i) to any finance provider in conjunction with a
financing transaction, if such finance provider agrees to keep this Agreement
confidential, (ii) to any legal or financial advisor of such party, or (iii) in
response to a subpoena or other validly issued administrative

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       16
<Page>

or judicial process requesting disclosure of same; PROVIDED, the party that
receives such order or process provides prompt notice to the disclosing party
before making any disclosure and permits the disclosing party to oppose or
narrow such request for disclosure and supports any of disclosing party's
reasonable efforts to oppose such request (at disclosing party's expense) and
shall disclose the terms of this Agreement only in the event of a final judgment
or administrative order requiring such disclosure, and only to the extent
necessary to comply with such request.

     (b) Each party will restrict disclosure of the other party's Confidential
Information to those of its employees to whom it is necessary to disclose such
Confidential Information in connection with the purposes permitted under Section
5.2(a). Each party shall use reasonable efforts, including at least efforts
fully commensurate with those employed by the party for the protection of its
own Confidential Information, to protect the Confidential Information of the
other party.

     (c) Either disclosing party may at any time notify the receiving party that
such receiving party must return to the disclosing party the disclosing party's
Confidential Information. Each party hereby agrees to, within thirty (30) days
of such notification: (i) return all documents and tangible items it or its
employees or agents have received or created pursuant to this Agreement
pertaining, referring or relating to the other party's Confidential Information;
and (ii) return or certify (in a writing attested to by a duly authorized
officer of such party) destruction of all copies, summaries, modifications or
adaptations that such party or its employees or agents have made from the
materials provided by the disclosing party.

     (d) Nothing herein shall prevent a receiving party from disclosing all or
part of the Confidential Information as necessary pursuant to the lawful
requirement of a governmental agency or when disclosure is required by operation
of law; PROVIDED that prior to any such disclosure, the receiving party shall
use reasonable efforts to: (i) promptly notify the disclosing party in writing
of such requirement to disclose; and (ii) cooperate fully with the disclosing
party in protecting against any such disclosure or obtaining a protective order.

5.3 PUBLICATIONS. Each party recognizes that the publication of papers regarding
results of the Program, including oral presentations and abstracts, may be
beneficial to both parties provided such publications are subject to reasonable
controls to protect Confidential Information. In particular, it is the intent of
the parties to maintain the confidentiality of any Confidential Information
regarding the compounds included in any patent application until such patent
application has been published. Accordingly, each party shall have the right to
review and comment upon any paper proposed for publication by the other party
regarding results of the Program, including oral presentations and abstracts,
which utilizes data generated from the Program or includes Confidential
Information of the other party and neither party will make any publication or
disclosure regarding the results of the Program without the prior written
consent of the other party. Before any such paper is submitted for publication,
the party proposing publication shall deliver a complete copy to the other party
at least thirty (30) days prior to submitting the paper to a publisher. The
receiving party shall review any such paper and give its comments to the
publishing party within twenty (20) days of the delivery of such paper to the
receiving party. With respect to oral presentation materials, the parties shall
make reasonable efforts to expedite review of such materials, and shall return
such items as soon as practicable to the disclosing party with appropriate
comments, if any, but in no event later than twenty (20) days from the date of
delivery to the receiving party. The disclosing party shall comply with the
other party's request to delete references to such other party's Confidential
Information in any such paper and agrees to withhold publication of same for an
additional one hundred eighty (180) days (or longer if necessary) in order to
permit the parties to obtain patent protection, if either of the parties deem it
necessary, in accordance with the terms of this Agreement. If there is a dispute
regarding publications, such dispute shall be resolved by the Steering
Committee.

6.  REPRESENTATIONS AND WARRANTIES.

6.1 AUTHORIZATION; ENFORCEABILITY. Each of Aventis and NeoGenesis represent and
warrant to the other that: (a) it is a corporation or limited liability company,
as applicable, duly organized and validly existing under the laws of its
jurisdiction of organization and has all requisite power and authority to enter
into this Agreement; (b) it is duly authorized by all requisite action to
execute, deliver and perform this Agreement and to consummate the transactions
contemplated hereby, and that the same do not conflict or cause a default with
respect to such party's obligations

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       17
<Page>

under any other agreement; (c) it has duly executed and delivered this
Agreement; and (d) (i) it is authorized to disclose any and all Confidential
Information made available to the other party pursuant to this Agreement; and
(ii) it shall not disclose to the other party any information that is
confidential or proprietary to itself or to a third party unless such
information is identified as Confidential Information.

6.2 NEOGENESIS PERFORMANCE. (a) NeoGenesis hereby represents and warrants to
Aventis that: (i) NeoGenesis shall use Commercially Reasonable Efforts to
perform the Program using qualified personnel and in a good and workmanlike
manner consistent with industry standards of companies that are comparable to
NeoGenesis performing similar activities under similar circumstances; and (ii)
as of the Effective Date, there is no agreement known to NeoGenesis to which it
is a party and by which it is bound that would conflict with or be breached by
NeoGenesis granting Aventis the license in Section 3.1.

     (b) NeoGenesis hereby represents and warrants to Aventis that it has not
sought, and will not seek, patent protection on any of the compounds that will
be screened in the conduct of the Program.

6.3 DISCLAIMER. (a) EXCEPT FOR THE WARRANTIES EXPRESSLY MADE IN SECTIONS
6.1-6.2, NeITHER PARTY MAKES ANY OTHER REPRESENTATION OR WARRANTY, EITHER
EXPRESS OR IMPLIED (WHETHER WRITTEN OR ORAL), INCLUDING, WITHOUT LIMITATION ANY
WARRANTY AGAINST INFRINGEMENT OF ANY THIRD PARTY PATENT OR OTHER INTELLECTUAL
PROPERTY RIGHTS, ANY WARRANTY OF MERCHANTABILITY OR ANY WARRANTY OF FITNESS FOR
A PARTICULAR PURPOSE WITH RESPECT TO THE NeoMorph Screening Library, the
NeoMorph Focused Libraries, QSCD, the Preliminary Compounds, the Primary Active
Compounds, the Selected Compounds, the LEAD Compounds, THE SCREENING TARGETS,
THE PRODUCTS, THE NeoGenesis intellectual property, THE Aventis intellectual
property, THE SCOPE, VALIDITY OR ENFORCEABILITY OF THE NeoGenesis PATENT RIGHTS
OR THE Aventis PATENT RIGHTS, OR SUCH PARTy'S OBLIGATIONS UNDER THIS AGREEMENT.

     (b) THE REPRESENTATIONS AND WARRANTIES OF EACH OF NeoGenesis AND Aventis
EXTEND ONLY TO THE OTHER PARTY. NEITHER PARTY WILL BE LIABLE FOR ANY CLAIM OR
DEMAND AGAINST SUCH OTHER PARTY BY A THIRD PARTY, EXCEPT TO THE EXTENT PROVIDED
IN SECTIONS 7.2-7.3.


7.  RISK ALLOCATION

7.1 LIMITATION OF LIABILITY. EXCEPT FOR BREACH OF CONFIDENTIALITY OBLIGATIONS
UNDER SECTION 5 AND EXCEPT AS OTHERWISE PROVIDED IN SECTIONS 7.2-7.3 WITH
RESPECT TO THIRD PARTY CLAIMS, IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE
OTHER FOR LOST PROFITS OR SAVINGS OR FOR ANY INDIRECT, INCIDENTAL,
CONSEQUENTIAL, SPECIAL, PUNITIVE OR EXEMPLARY DAMAGES IN CONNECTION WITH THIS
AGREEMENT OR THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT, HOWEVER CAUSED,
UNDER ANY THEORY OF LIABILITY.

7.2 THIRD PARTY CLAIMS. Subject to the provisions of Section 7.4, each of
NeoGenesis and Aventis (each, in such capacity an INDEMNIFYING PARTY) will
defend, indemnify and hold harmless the other party, its subsidiaries, parent
corporations, affiliates, officers, directors, partners, members, shareholders,
employees, agents, and their successors and assigns (each, in such capacity, an
INDEMNIFIED PARTY) from and against any claim, suit, demand, loss, damage,
expense (including reasonable attorneys' fees of Indemnified Party(ies) and
those that may be asserted by a third party) or liability including but not
limited to claims for death or personal injury (collectively, LOSSES) imposed
upon the Indemnified Party(s) by any third party arising from or related to: (a)
any material breach of the Indemnifying Party's representations and warranties
under this Agreement; or (b) any negligence or intentional misconduct by the
Indemnifying Party (or its employees, agents, representatives, Affiliates,
licensees, sublicensees or distributors) in performing its obligations under
this Agreement, including the performance of the Program or the R&D Program; or
(c) (with respect to Aventis as an Indemnifying Party) the labeling, packaging,
package insert, other materials or promotional claims with respect to any
Product or the development, testing, Manufacturing, Commercialization, use or
other disposition of any Product by Aventis or by an Affiliate, licensee,
sublicensee, distributor or agent of

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       18
<Page>

Aventis. The foregoing indemnification action shall not apply in the event and
to the extent that such Losses arose as a result of any Indemnified Party's
negligence, intentional misconduct or breach of this Agreement.

7.3 INFRINGEMENT INDEMNIFICATION. (a) Subject to the provisions of Section 7.4,
NeoGenesis shall defend, indemnify and hold harmless the Aventis Indemnified
Party(ies) from and against any Losses imposed upon them by any third party and
arising from or related to a third party claim that use of NeoGenesis
Intellectual Property or practice of the NeoGenesis Patent Rights by Aventis in
accordance with the terms of this Agreement violates or infringes the
intellectual property rights of any third party. NeoGenesis shall have no
liability or obligation to Aventis under this Section 7.3(a) in the event and to
the extent that the alleged infringement results from willful misconduct or
negligent acts or omissions of Aventis or its Affiliates, or its or their
respective employees, officers, directors or agents.

     (b) Subject to the provisions of Section 7.4, Aventis shall defend,
indemnify and hold harmless the NeoGenesis Indemnified Party(ies) from and
against any Losses imposed upon them by any third party and arising from or
related to a third party claim that use of the Aventis Intellectual Property or
the practice of the Aventis Patent Rights by NeoGenesis in accordance with the
terms of this Agreement violates or infringes the intellectual property rights
of any third party. Aventis shall have no obligation or liability to NeoGenesis
under this Section 7.3(b) in the event and to the extent that the alleged
infringement (i) is covered by Section 7.3(a) or (ii) results from willful
misconduct or negligent acts or omissions of NeoGenesis or its Affiliates, or
its or their respective employees, officers, directors or agents.

7.4 PROCEDURE. To receive the benefit of indemnification under Sections 7.2 or
7.3, the Indemnified Party must (a) promptly notify the Indemnifying Party of a
claim or suit; PROVIDED, that failure to give such notice shall not relieve
Indemnifying Party of its indemnification obligations except where, and solely
to the extent that, such failure actually and materially prejudices the rights
of Indemnifying Party); (b) provide reasonable cooperation (at the Indemnifying
Party's expense); and (c) tender to the Indemnifying Party (and its insurer)
full authority to defend or settle the claim or suit; PROVIDED that no
settlement requiring any admission by the Indemnified Party or that imposes any
obligation on the Indemnified Party shall be made without the Indemnified
Party's consent. Neither party has any obligation to indemnify the other party
in connection with any settlement made without the Indemnifying Party's written
consent. The Indemnified Party has the right to participate at its own expense
in the claim or suit and in selecting counsel therefor. The Indemnified Party
shall cooperate with Indemnifying Party (and its insurer), as reasonably
requested, at Indemnifying Party's cost and expense.


8.   TERM AND TERMINATION

8.1 TERM. This Agreement shall take effect as the Effective Date and shall
remain in effect until the expiration date(s) specified in this Section 8.1,
unless sooner terminated in accordance with Section 8.2. The duration of the
Program will be thirty six (36) months from the Effective Date or such longer
period as is required for NeoGenesis to complete the Program in accordance with
Section 2.4 (the PROGRAM TERM). If the license under Section 3.1 is exercised,
such license will remain in effect on a country-by-country basis until the LATER
OF: (a) the expiration of the term of the last-to-expire of the patent rights
within the NeoGenesis Intellectual Property or Program Intellectual Property
owned by or licensed to NeoGenesis (including those NeoGenesis Patent Rights
assigned to Aventis pursuant to Section 3.2(d)) covering the applicable Lead
Compounds or the corresponding Product or (b) ten (10) years following the First
Commercial Sale of such Product.

8.2 TERMINATION. (a) NeoGenesis may terminate the Program with thirty (30) days'
notice to Aventis if Aventis fails to pay fees not contested in good faith due
under the Agreement or commits a material breach, unless the nonpayment or
breach is cured within the 30-day notice period. Aventis may terminate the
Program with thirty (30) days notice to NeoGenesis if NeoGenesis commits a
material breach unless the breach is cured within the thirty (30)-day notice
period. In addition, NeoGenesis may suspend work pursuant to the Program with
notice to Aventis if Aventis fails to pay NeoGenesis any amount due NeoGenesis
under this Agreement.

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       19
<Page>

     (b) Aventis may terminate the Program on the first anniversary of the
Effective Date based on Aventis' dissatisfaction with the results of the
Screening Program. Aventis may terminate the Hit Exploration Program at any time
with or without cause upon one hundred eighty (180) days notice.

     (c) Following completion of the Program, either party may terminate the
license, on a Product-by-Product basis, with sixty (60) days notice if the other
commits a material breach (including non-payment) unless the breach is cured
within the sixty (60)-day notice period.

     (d) Either party shall have the right to terminate this Agreement upon
thirty (30) days notice if a Force Majeure condition has prevented performance
by the other party for more than one hundred twenty (120) consecutive days. The
parties may also terminate this Agreement at any time upon mutual written
agreement of the parties.

     (e) Aventis shall have the right to terminate the license on a Lead
Compound-by-Lead Compound basis at any time with sixty (60) days notice.

8.3 EFFECT OF TERMINATION. (a) Upon termination (including expiration) of this
Agreement: (i) NeoGenesis will terminate all Program tasks (if any) then in
process in an orderly manner, as soon as practical and in accordance with a
schedule agreed to by Aventis and NeoGenesis; (ii) Aventis shall pay NeoGenesis
any monies due and owing NeoGenesis up to the time of termination, for services
actually performed (including all work-in process (if any) pursuant to the last
sentence of Paragraph 7 or Paragraph 8 of ATTACHMENT A), PROVIDED, such fee
shall not exceed the price specified in this Agreement and (iii) within thirty
(30) days following termination (including expiration) of this Agreement,
NeoGenesis shall deliver to Aventis a reasonably-detailed written report
describing the results of the Program services performed up to the date of such
termination.

     (b) Upon termination (including expiration) of this Agreement each party
shall return to the other party or certify in writing to the other party that it
has destroyed all documents and other tangible items it or its employees or
agents have received or created pertaining, referring or relating to the
Confidential Information of the other party.

     (c) The licenses granted by NeoGenesis under Section 3.1 shall survive any
expiration or termination of the Program or this Agreement with respect to any
Lead Compound or Product for which the applicable fees and milestone fees and
royalties have been paid (when due in accordance with the terms of this
Agreement) and Aventis shall continue to have the right to develop, have
developed, make, have made, use, distribute, offer for sale, import, export and
sell Lead Compounds and Products; PROVIDED that Aventis continues to pay
NeoGenesis the fees and royalties as required by Sections 4.1, 4.3 and 4.4 and
complies with Sections 4.5-4.8. The licenses granted under Section 3.1 shall not
survive termination or expiration with respect to Lead Compounds or Products for
which Aventis has not made payment in accordance with this Agreement and shall
immediately terminate with respect to any Lead Compound or Product for which the
applicable service fees and milestone fees are not timely paid (should such
payment become due after termination of this Agreement or for any Product for
which Aventis fails to pay NeoGenesis fees and royalties as required by Sections
4.1, 4.3 and 4.4 or fails to comply with Sections 4.5-4.8 subject to the
opportunity to cure described in Section 8.2(b). In the event the license
granted to Aventis under Section 3.1 terminates for any reason, each of Aventis'
sublicensees at such time shall continue to have the rights and license set
forth in their sublicense agreements, PROVIDED such sublicensee agrees in
writing that NeoGenesis is entitled to enforce all relevant provisions directly
against such sublicensee.

     (d) Except as otherwise provided herein, neither party shall be liable to
the other party for any compensation or damages by reason of termination of this
Agreement in accordance with this Section 8.

     (e) Nothing herein shall be construed to release either party of any
obligation which matured prior to the effective date of any termination.
Aventis' liability for any charges, payments or expenses due to NeoGenesis that
accrued prior to the termination date shall not be extinguished by termination,
and such amounts (if not otherwise due on an earlier date) shall be immediately
due and payable on the termination date.

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMMISSION.

                                       20
<Page>

8.4 SURVIVAL. Sections 1, 2.8, 3.2, 3.3 and 5-9 shall survive any termination or
expiration of this Agreement. Section 4 shall survive any termination of this
Agreement with respect to Products (including Products that are covered by
Section 3.2(d)) PROVIDED, that Section 4 shall not survive expiration of this
Agreement with respect to any Product in accordance with the last sentence of
Section 8.1.


9.  GENERAL PROVISIONS.

9.1 ISSUE RESOLUTION. The parties shall use their best efforts to resolve any
controversy or dispute that arises under or relates to this Agreement through
good faith discussions. The parties shall initiate such discussions using the
following procedure. Either party shall notify the other party of the nature of
the controversy or dispute, providing sufficient detail to permit the other
party to understand same (a DISPUTE NOTICE). The representatives of the parties
shall meet within 30 days after the date that the non-sending party receives the
Dispute Notice to attempt to reach an agreement about the nature of the dispute
and a resolution of the dispute. If they are unable to resolve the dispute
within 60 days after their meeting, and do not agree to extend the time period
for resolving the dispute, or if the terms and conditions of the resolution or
settlement of the dispute are breached, the parties are free to pursue any
remedy at law or in equity. Pending resolution of any dispute covered by this
Section 9.1, both parties will continue their performance under this Agreement
including, without limitation, the payment of all amounts due to the other party
that are not in dispute.

9.2 GOVERNING LAW. This Agreement shall be governed and construed in accordance
with the internal, substantive laws of the State of New York to the exclusion of
any choice or conflict of laws rule or provision that would result in the
application of the substantive law of any other jurisdiction. Notwithstanding
the foregoing, the parties shall use United States (Federal) patent laws for
purposes of governing and construing Sections 3.2-3.4 of this Agreement. The
United Nations Convention on Contracts for the International Sale of Goods shall
not apply to the transactions contemplated by this Agreement.

9.3 AMENDMENT AND WAIVER. No provision of or right under this Agreement shall be
deemed to have been waived by any act or acquiescence on the part of either
party, its agents or employees, but only by an instrument in writing signed by
an authorized officer of each party. No waiver by either party of any breach of
this Agreement by the other party shall be effective as to any other breach,
whether of the same or any other term or condition and whether occurring before
or after the date of such waiver.

9.4 INDEPENDENT CONTRACTORS. Each party represents that it is acting on its own
behalf as an independent contractor and is not acting as an agent for or on
behalf of any third party. This Agreement and the relations hereby established
by and between Aventis and NeoGenesis do not constitute a partnership, joint
venture, franchise, agency or contract of employment. Neither party is granted,
and neither party shall exercise, the right or authority to assume or create any
obligation or responsibility on behalf of or in the name of the other party or
its Affiliates. NeoGenesis shall be solely responsible for compensating all its
personnel and for payment of all related FICA, workers' compensation,
unemployment and withholding taxes. Aventis shall not provide NeoGenesis
personnel with any benefits, including but not limited to compensation for
insurance premiums, paid sick leave or retirement benefits.

9.5 ASSIGNMENT. Neither party may assign this Agreement or any of its rights and
obligations under this Agreement without the prior written consent of the other
party; PROVIDED, that either party may assign this Agreement to (a) any Person
to which such party transfers all or substantially all of its assets or with
which such party is consolidated or merged; (b) any Person that owns a majority
of the voting stock of such party; (c) a single Person of which such party owns
a majority of the voting stock; or (d) an Affiliate of the assigning party;
PROVIDED, FURTHER, that in each instance the assignee expressly assumes all
obligations imposed on the assigning party by this Agreement in writing and the
other party is notified in advance of such assignment.

9.6 SUCCESSORS AND ASSIGNS. This Agreement shall bind and inure to the benefit
of the parties hereto and their respective successors and permitted assigns.

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9.7 NOTICES. Unless otherwise provided herein, any notice, report, payment or
document to be given by one party to the other shall be in writing and shall be
deemed given when delivered personally or mailed by certified or registered
mail, postage prepaid (such mailed notice to be effective on the date which is
three (3) business days after the date of mailing), or sent by nationally
recognized overnight courier (such notice sent by courier to be effective one
business day after it is deposited with such courier), or sent by telefax (such
notice sent by telefax to be effective when sent, if confirmed by certified or
registered mail or overnight courier as aforesaid) to the address set forth on
the signature page to this Agreement or to such other place as any party may
designate as to itself by written notice to the other party.

9.8 SEVERABILITY. In the event any provision of this Agreement shall for any
reason be held to be invalid, illegal or unenforceable in any respect, such
invalidity, illegality or unenforceability shall not affect any other term or
provision hereof. The parties agree that they will negotiate in good faith or
will permit a court or arbitrator to replace any provision hereof so held
invalid, illegal or unenforceable with a valid provision which is as similar as
possible in substance to the invalid, illegal or unenforceable provision.

9.9 CAPTIONS. Captions of the sections and subsections of this Agreement are for
reference purposes only and do not constitute terms or conditions of this
Agreement and shall not limit or affect the meaning or construction of the terms
and conditions hereof.

9.10 WORD MEANINGS. Words such as HEREIN, HEREINAFTER, HEREOF and HEREUNDER
refer to this Agreement as a whole and not merely to a section or paragraph in
which such words appear, unless the context otherwise requires. The singular
shall include the plural, and each masculine, feminine and neuter reference
shall include and refer also to the others, unless the context otherwise
requires.

9.11 ENTIRE AGREEMENT. The terms and provisions contained in this Agreement
(including the Attachments) constitute the entire understanding of the parties
with respect to the transactions and matters contemplated hereby and supersede
all previous communications, representations, agreements and understandings
relating to the subject matter hereof. No representations, inducements, promises
or agreements, whether oral or otherwise, between the parties not contained in
this Agreement shall be of any force or effect. No agreement or understanding
extending this Agreement or varying its terms (including any inconsistent terms
in any purchase order, acknowledgment or similar form) shall be binding upon
either party unless it is in a writing specifically referring to this Agreement
and signed by a duly authorized representative of the applicable party.

9.12 RULES OF CONSTRUCTION. The parties agree that they have participated
equally in the formation of this Agreement and that the language and terms of
this Agreement shall not be construed against either party by reason of the
extent to which such party or its professional advisors participated in the
preparation of this Agreement.

9.13 COUNTERPARTS. This Agreement may be executed in multiple counterparts, each
of which shall be deemed an original, but all of which together shall constitute
one and the same instrument. In making proof of this Agreement, it shall not be
necessary to produce or account for more than one such counterpart.

9.14 FORCE MAJEURE. Except as otherwise provided in this Agreement, in the event
that a delay or failure of a party to comply with any obligation, other than a
payment obligation, created by this Agreement is caused by a Force Majeure
condition, that obligation shall be suspended during the continuance of the
Force Majeure condition.

9.15 FURTHER ASSURANCES. Each party covenants and agrees that, subsequent to the
execution and delivery of this Agreement and without any additional
consideration, it will execute and deliver any further legal instruments and
perform any acts which are or may become reasonably necessary to effectuate the
purposes of this Agreement.

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IN WITNESS WHEREOF the parties have caused this Agreement to be executed on
their behalf by their duly authorized representatives intending it to take
effect as an instrument under seal as of the Effective Date.

NeoGenesis PHARMACEUTICALS, INC.        Aventis PHARMA S.A.


Name:         Peter T. Lomedico         Name:        Emmanuel Canet
Title:        Vice President            Title:       Directeur General
              Strategic Alliances
Signature:    /s/ Peter T. Lomedico     Signature:   /s/ Emmanuel Canet

Date:         December 20, 2001         Date:        December 21, 2001

NOTICE ADDRESS:                         NOTICE ADDRESS:
NeoGenesis Pharmaceuticals, Inc.        Aventis Pharma S.A.
                                        attn. R. Fleer
840 Memorial Drive                      13, quai Jules Guesde B.P. 14  94403
                                        Vitry-sur-Seine
Cambridge, MA 02139                     Cedex, France
Phone:  617.868.1500                    Phone: 33.1.55.71.33.55
Fax:  617.868.1515                      Fax: 33.1.55.71.33.77

                                        With a copy to:
                                        Aventis Pharmaceuticals Inc.
                                        attn. Vice President, Legal Corporate
                                        Development
                                        Mail Stop: BWA-303H
                                        Route 202-206
                                        Bridgewater, NJ 08807-0800
                                        Phone: 908.231.3537
                                        Fax: 908.231.4480

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                                  ATTACHMENT A
                                RESEARCH PROGRAM

The Program to be performed by NeoGenesis with respect to the Screening Targets
will screen [*] compounds contained in the NeoGenesis NeoMorph Screening Library
against each Screening Target using the protocol described below.

SCREENING PHASE

1. Aventis will provide NeoGenesis with at least [*] nmol. of each of the
purified functionally-active Screening Target proteins. NeoGenesis will perform
initial experiments on the Screening Targets to determine screening conditions
in NeoGenesis' ALIS protocols. NeoGenesis will establish SOPs for ALIS screening
based on the preceding experiments.

2. Using the SOPs, NeoGenesis will perform ALIS screening of at least [*] and up
to [*] NeoMorph compounds against each Screening Target, such number being
determined by the Steering Committee on a Screening Target-by-Screening Target
basis. The ALIS screening will be carried out under moderately stringent
conditions to identify compounds that bind to the Screening Target with binding
affinities better than [*] micromolar (Kd < [*]) (each a PRELIMINARY COMPOUND).
The Steering Committee will review the Kds of such Preliminary Compound(s) and
select those that warrant further work.

3. NeoGenesis will purify or synthesize up to [*] Preliminary Compounds per
Screening Target selected by the Steering Committee for further work and will
deliver to Aventis [*] of each of these "discrete" Preliminary Compounds to
Aventis; PROVIDED, that upon the determination of the Steering Committee that
more than [*] discrete Preliminary Compounds should be synthesized for any
Screening Target, NeoGenesis will synthesize such additional discrete
Preliminary Compounds as directed by the Steering Committee and Aventis shall
reimburse NeoGenesis for the costs to synthesize such additional discrete
Preliminary Compounds. Aventis will evaluate the activity of these discrete
Preliminary Compound(s) in biochemical or in vitro functional assay or
Aventis will transfer such assays to NeoGenesis for evaluation of such
discrete preliminary Compounds at NeoGenesis. The party responsible for
evaluating the activity of such discrete Preliminary Compound(s) will notify
the other party of any discrete Preliminary Compound which has demonstrated
activity in a Screening Target-based biochemical/functional assay with IC50
of less than [*] micromolar (IC50 < [*]) and will notify the other party of
the results of such assays, including any discrete Preliminary Compound(s)
which has demonstrated activity in the Screening Target-based
biochemical/functional assays with IC50 of less than [*] micromolar (IC50
< [*]) (each, a PRIMARY ACTIVE COMPOUND) within [*] after completion of such
assays and not later than [*] after receipt of the discrete Preliminary
Compounds or the Screening Target-based biochemical /functional assay, as
applicable.

4. If either Aventis or NeoGenesis identifies one or more Primary Active
Compounds pursuant to Paragraph 3, then NeoGenesis will prepare a report for all
Primary Active Compound(s) that details the chemical structures, binding
affinities and IC50 values for such Primary Active Compound(s). NeoGenesis will
deliver such report to Aventis when it notifies Aventis of such Primary Active
Compounds or, if Aventis has conducted the biochemical/functional assays, within
[*] of receipt of the results of such assays from Aventis.

5. Aventis will select up to [*] Primary Active Compounds per Screening
Target, for further study or optimization by NeoGenesis. NeoGenesis will
perform [*]cycles of optimization for the Primary Active Compounds identified
by Aventis. To perform such optimization, NeoGenesis will create NeoMorph
Focused Libraries based upon such Primary Active Compounds and will perform
high stringency-ALIS screening to improve Kd values to [*] micromolar or
better (Kd < [*]) and to develop a preliminary SAR. The results of
this additional ALIS screening will be summarized in a report (each, a FINAL
TARGET REPORT) and submitted to the Aventis Hit Evaluation Committee (HEC)
for consideration.

6. The HEC may select one or more compounds (each, a HIT COMPOUND) from the
optimized Primary Active Compounds prepared by NeoGenesis pursuant to Paragraph
5. In selecting Hit Compounds, the HEC will consider

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in good faith whether these satisfy the following criteria: (a) IC50/dose
response confirmed on purified/ re-synthesized Primary Active Compound; (b)
functional activity confirmed on purified/ re-synthesized Primary Active
Compound; (c) potential for chemical optimization of such Primary Active
Compound; (d) whether such Primary Active Compound is likely to lead to
patentable compounds; (e) selectivity of such Primary Active Compound on project
specific secondary assays (screening tree); (f) activity of such Primary Active
Compound in functional assay; (g) solubility; (h) mode of action of such Primary
Active Compound (case by case basis); and (i) whether such Primary Active
Compound revealed some SAR in small series ([*] compounds).


HIT EXPLORATION PHASE

7. NeoGenesis will purify or synthesize discrete Hit Compounds and will provide
Aventis with [*] of each discrete Hit Compound(s) for evaluation by Aventis in
Screening Target-based biochemical or in vitro functional assays (or Aventis
will transfer such assays to NeoGenesis for evaluation of such Hit Compounds at
NeoGenesis) and, at the direction of the Steering Committee, evaluation in
anti-infective, cytotoxicity and any other additional assays as determined by
the Steering Committee. NeoGenesis will prepare a report of such evaluation
including structures, Kds, IC50 values and results of all assays and will
deliver the report to Aventis within [*] following the completion of such
evaluation. Any additional quantities of Hit Compounds will be furnished to
Aventis at cost, which shall be based on the FTE rate.

8. Aventis will select a series of Hit Compounds for further optimization (each,
a SELECTED SERIES). NeoGenesis will perform additional optimization and all
necessary assays as directed by the Steering Committee to optimize the Selected
Series compounds to meet the Lead Compound criteria specified in clauses (a)-(h)
of the definition of Lead Compound(s). All such work will be carried out on FTE
basis and Aventis will provide funding for such work as provided in Section 4.2.
The decision whether any of the optimized Hit Compounds should be nominated as
Lead Compounds will be based on a detailed report (each, a CANDIDATE LEAD
COMPOUND REPORT) and a written recommendation of the Steering Committee. The
final decision on a Lead Compound nomination will be taken by the Aventis
Scientific Review Committee (SRC) in accordance with Section 2.8.

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WORK FLOWCHART

                          [GRAPHICS OF WORK FLOWCHART]

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                                  ATTACHMENT B
                          PROGRAM INTELLECTUAL PROPERTY
                          [TO BE SUPPLIED AS DEVELOPED]


                                  ATTACHMENT C
                                SCREENING TARGETS
                           [TO BE SUPPLIED BY AVENTIS]


                                  ATTACHMENT D
                        NEOGENESIS INTELLECTUAL PROPERTY
                  [TO BE SUPPLIED BY NEOGENESIS AS APPLICABLE]

                            NEOGENESIS PATENT RIGHTS
                  [TO BE SUPPLIED BY NEOGENESIS AS APPLICABLE]

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