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                                                                   Exhibit 10.15

                             CONFIDENTIAL TREATMENT

                                    AGREEMENT

This Agreement (AGREEMENT) is entered into as of October 18 2001 (EFFECTIVE
DATE) between NeoGenesis Drug Discovery, Inc., a Delaware corporation
(NEOGENESIS), and Immusol Incorporated (IMMUSOL), a California corporation.

                                   BACKGROUND

Immusol is interested in identifying potential pharmaceutical products for the
treatment of human immunodeficiency virus (HIV) and wishes to identify compounds
that exhibit a high degree of chemical binding and functional activity to
specific protein targets involved in HIV. NeoGenesis has certain technology and
know-how, including screening processes and 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 activity to targets designated by Immusol 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 only, "CONTROL" means, with respect to
any Person, the direct or indirect ownership of more than fifty percent (50%) of
the voting or income interest in such Person or the possession otherwise,
directly or indirectly, of the power to 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 target protein.

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      APPLICABLE LAWS means all applicable laws, statutes, regulations and
ordinances, including without limitation the FD&C Act.

      COMMERCIALLY REASONABLE EFFORTS means (i) with respect to any objective
by any party, commercially 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 Shared 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, product profile,
the competitiveness of the marketplace, the proprietary position of the product,
the regulatory structure involved, profitability of the product and other
relevant commercial factors.

      COMMERCIALIZATION means any and all activities of importing, exporting,
marketing, promoting, distributing, offering for sale and selling a Shared
Product or Independent Product. 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 Immusol Intellectual Property
and all NeoGenesis Intellectual Property) disclosed to the other party pursuant
to this Agreement, except any portion thereof which: (i) is known to the
receiving party, as evidenced by the receiving party's prior 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
public domain 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.

      CONTROL OR CONTROLLED means, with respect to any intellectual property
right, the possession (whether by ownership or license) 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 or right without violating the terms of any
agreement or other arrangements between such party or its

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SEPARATELY WITH THE COMMISSION.

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Affiliate and any third party existing before, or acquired after, the Effective
Date.

      COST OF GOODS means the cost of manufacturing the Designated Shared
Compound or Shared Product or Independent Compound or Independent Product in
bulk or finished form (including samples) calculated in accordance with GAAP.
Cost of Goods shall include: (a) the Cost of Manufacture for the Designated
Shared Compounds and Shared Products or the Independent Compounds and
Independent Products manufactured by either party or the amount paid for the
Designated Shared Compounds and Shared Products or the Independent Compounds and
Independent Products manufactured by a third party; and (b) the net cost or
credit of any value-added taxes or duties actually paid or utilized in respect
of the Designated Shared Compounds and Shared Products or the Independent
Compounds and Independent Products.

      COST OF MANUFACTURE means the fully-allocated cost of manufacturing
Designated Shared Compounds and Shared Products or the Independent Compounds and
Independent Products (calculated in accordance with GAAP), including the direct
and indirect cost of any raw materials, packaging materials and labor (including
the cost of employee benefits) utilized in such manufacturing (including
formulating, filling, finishing, labeling and packaging, as applicable) plus
factory overhead costs (fixed and variable) allocated to the relevant Designated
Shared Compound, Shared Product, Independent Compound or Independent Product in
accordance with normal accounting practices for all products manufactured in the
applicable facility.

      DERIVATIVE COMPOUNDS means any analogs, homologs or isomers of a
Designated Shared Compound and/or an Independent Compound, as applicable.

      DEVELOPMENT shall mean the development of any Shared Product occurring
from and after the filing of an IND, through and including approval of an NDA
and any other Regulatory Approvals required for the Manufacture and
Commercialization of such Shared Product in a country. Development shall not
include Pre-Clinical Development activities.

      DEVELOPMENT COSTS shall mean all costs and expenses reasonably
resulting directly from the Pre-Clinical Development of any Designated Shared
Compound or Development of any Shared Product, as well as Overhead costs of the
functions that directly support such Pre-Clinical

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Development or Development (as calculated in accordance with GAAP and using the
same allocation methods that the party incurring such costs uses throughout its
operations, but in all events excluding General Corporate Overhead), all as
specified in the Development Plan and the Development Budget. DEVELOPMENT COSTS
shall include, without limitation: (i) the Cost of Goods for the Designated
Shared Compound used in such Pre-Clinical Development or Shared Product used in
such Development (including early batches of the Shared Product for use in
obtaining Regulatory Approval, to the extent not re-used later in commercial
sales); (ii) direct costs for third party professional Pre-Clinical Development
or Development services, including without limitation toxicology studies or
clinical studies performed by third parties; (iii) direct charges for materials
(including without limitation chemicals, animals and lab supplies); (iv) labor
and materials costs and fees incurred in connection with securing Regulatory
Approvals; (v) labor and materials costs for the Development of the
Manufacturing process for Shared Products and scale-up of such process; and (vi)
the costs of FTEs dedicated to the foregoing activities.

      DIRECT ADMINISTRATIVE EXPENSES means the costs of invoicing, tracking
and administering rebate and chargeback programs and product returns and of
establishing and maintaining contracts with managed care organizations and
governmental purchasers.

      DISTRIBUTION COSTS means the costs of distributing and shipping the
Shared Product and samples to wholesalers, distributors, physicians and
customers (including costs of returns) and costs of collection. In the event
that such costs cannot be calculated on a Shared Product-by Shared Product
basis, such costs shall be calculated by multiplying: (i) the aggregate
distribution costs incurred by the party's pharmaceutical business for all
pharmaceutical products that shall be calculated correspondingly according to
the formula set forth in this paragraph; by (ii) a fraction, (x) the numerator
of which is the Net Sales for such Shared Product; and (y) the denominator of
which is the total net sales of all pharmaceutical products of the party's
pharmaceutical business that shall be calculated correspondingly according to
the formula for Net Sales under this Agreement.

      EXPENSES means expenses incurred by a party to the extent allocable to
the Commercialization of Shared Products in all countries in the Territory,
calculated in accordance with GAAP. EXPENSES shall include: (a) the Cost of
Goods; (b) Pre-Launch Expenses; (c) Distribution Costs; (d) Selling and
Promotion Expenses; (e) Third Party Royalties; (f)

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Post-Regulatory Approval Clinical Studies Expenses; (g) Direct Administrative
Expenses; (h) Recall Expenses; and (i) Other Allowable Expenses.

      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 and applicable regulations promulgated thereunder, as amended from time to
time.

      FIELD means all preventative, therapeutic and diagnostic uses of Shared
Products or Independent Products with respect to human immunodeficiency virus
(HIV) in humans.

      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.

      FORCE MAJEURE means any event beyond the control of the parties,
including, without limitation, power outages, 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 the equivalent of a full time (12) months (including normal
vacations, sick days and holidays) work of a person, carried out by one or more
employees or agents of a party.

      GAAP shall mean United States Generally Accepted Accounting Principles,
consistently applied.

      GENERAL CORPORATE OVERHEAD shall mean all expenses that are not primarily
associated with research, Pre-Clinical Development or Development functions of
either party. Such expenses include salaries and benefits of executive officers
(unless primarily involved in research, Pre-Clinical Development or Development
activities), administrative support for such officers, and all costs of the
finance, purchasing, legal (including both in-house and outside counsel),
business development and corporate development functions of both parties. In the
event that such costs cannot

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be calculated on a Designated Shared Compound-by-Designated Shared Compound or
Shared Product-by-Shared Product basis, such costs shall be calculated by
multiplying: (i) the aggregate general corporate overhead incurred by the
party's pharmaceutical business for all pharmaceutical products that shall be
calculated correspondingly according to the formula set forth in this paragraph;
by (ii) a fraction, (x) the numerator of which is the Net Sales for such Shared
Product; and (y) the denominator of which is the total net sales of all
pharmaceutical products of the party's pharmaceutical business that shall be
calculated correspondingly according to the formula for Net Sales under this
Agreement.

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

      GOOD LABORATORY PRACTICES or GLP means the then current standards for
laboratory activities for pharmaceuticals, as set forth in the FD&C Act and such
standards of good laboratory practice as are required by the European Union and
other Regulatory Authorities in countries in which the relevant product is
intended to be sold, to the extent such standards are not in contravention with
United States Good Laboratory Practices.

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

      IMMUSOL 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 Immusol 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 Immusol
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 and/or

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secondary assays provided by Immusol under the Program. The term Immusol
Intellectual Property, HOWEVER, does not include any techniques, methodologies,
know-how, information and data which is, as of the Effective Date or later
becomes, generally available to the public, other than such techniques,
methodologies, know-how, information and data included in Immusol Patent Rights.

      IMMUSOL PATENT RIGHTS means (a) those patents and patent applications
covering Immusol Intellectual Property and Program Intellectual Property owned
by or licensed to Immusol that are Controlled by Immusol at any time during the
term of this Agreement which relate to or otherwise would be infringed by the
performance of the Screening Program or the Development, Manufacture, use,
importation or sale of any Designated Shared Compound or Shared Product and, to
the extent permitted under Section 3.15, Independent Compounds and Independent
Products and (b) all divisionals, continuations, continuations-in-part,
reissues, extensions, supplementary protection certificates and foreign
counterparts thereof.

      IND means an investigational new drug application, as defined in the
FD&C Act, or any equivalent document filed with the FDA and necessary for
beginning clinical trials of any product in humans or any 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 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).

      MANUFACTURING means any and all activities involved in the production of a
Designated Shared Compound or an Independent Compound (and Derivative Compounds
thereof) or a Shared Product or a Independent Product to be developed and/or
Commercialized under this Agreement. When used as a verb, MANUFACTURE means to
engage in Manufacturing.

      MARKETING, ADVERTISING AND EDUCATION EXPENSES means the costs of public
relations, advertising, promotion and marketing of the Shared Product through
any means (including agency fees, advertisements, marketing management,
promotional literature, market research,

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symposia, exhibits and direct mail) and the costs of educating physicians and
customers about use of the Shared Product. In the event that such costs cannot
be calculated on a Shared Product-by-Shared Product basis, such costs shall be
calculated by multiplying: (i) the aggregate marketing, advertising and
education expenses incurred by the party's pharmaceutical business for all
pharmaceutical products that shall be calculated correspondingly according to
the formula set forth in this paragraph; by (ii) a fraction, (x) the numerator
of which is the Net Sales for such Shared Product; and (y) the denominator of
which is the total net sales of all pharmaceutical products of the party's
pharmaceutical business that shall be calculated correspondingly according to
the formula for Net Sales under this Agreement.

      NDA means a new drug application as defined in the FD&C Act and 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 Immusol 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, ALIS and QSCD. The term NeoGenesis Intellectual Property, HOWEVER, does
not include any techniques, methodologies, know-how, information and data which
is, as of the Effective Date, or later becomes, generally available to the
public, other than such techniques, methodologies, know-how, information and
data included in NeoGenesis Patent Rights.

      NEOGENESIS PATENT RIGHTS means those (a) patents and patent applications
covering NeoGenesis Intellectual Property and Program Intellectual Property
owned by or licensed to NeoGenesis that are Controlled by NeoGenesis at any time
during the term of this Agreement; and (b) all divisionals, continuations,
continuations-in-part, reissues, extensions, supplementary protection
certificates and foreign counterparts thereof. NeoGenesis shall list all
NeoGenesis Patent Rights on ATTACHMENT D, which will be updated by NeoGenesis no
less frequently than quarterly during the term of this Agreement.

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      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 based upon Selected Compounds identified by Immusol.

      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, comprising approximately ten million
(10,000,000) different compounds.

      NET SALES means, with respect to any Shared Product or Independent
Product, the aggregate gross amount received by the parties, their Affiliates or
any of their sublicensees (in the case of a Shared Product) or by the
Independent Party, its affiliates or any of its sublicensees (in the case of an
Independent Product) from unrelated third party distributors or agents (in each
case, who are not sublicensees), or end users in the Territory for the sale or
transfer for value of the applicable Shared Product or Independent Product LESS
deductions for (a) trade, quantity and cash discounts and rebates allowed to and
taken by customers, (b) refunds, chargebacks and any other allowances actually
paid to or taken by customers, (c) amounts separately and actually credited to
customers for Shared Product or Independent Product returns, credits or
allowances, (d) rebates actually paid or credited to any governmental agency
(or branch thereof) or to any third party payor, administrator or contractee,
(e) discounts mandated by, or granted to meet the requirements of, applicable
state, provincial or federal law, paid or credited to a wholesaler, purchaser,
third party or other contractee including required chargebacks and retroactive
price reductions, (f) special outbound packing, transportation, freight,
handling, postage charges and other charges such as insurance relating thereto
that are separately billed to the customer or prepaid and (g) sales, excise,
value added, turnover, use and other like taxes or customs duties paid and any
other governmental charges, excluding net income tax, imposed upon the sale of
the applicable Shared Product or Independent Product. The amounts of any
deductions taken pursuant to clauses (a)-(g) shall be determined from books and
records maintained in accordance with GAAP. Net Sales shall not include revenue
received by a party (or any of its Affiliates) from transactions with an
Affiliate, where the Shared Product or Independent Product in question will be
resold to an independent third-party distributor or agent (in each

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case, who is not a sublicensee) or end user by the Affiliate where such revenue
received by the Affiliate from such resale is included in Net Sales. Revenue
received by a party (or any of its Affiliates) from transactions with an
Affiliate, where the Shared Product or Independent Product in question is used
by the Affiliate solely for such Affiliate's internal purposes shall also be
included in Net Sales at a price equal to the fair market value of such
transfer(s).

      In the event the applicable Shared Product or Independent Product is
sold as part of a combination product, or as part of a bundled product or as
part of a delivery system, the Net Sales from the combination product, bundled
product or delivery system, for the purposes of determining royalty payments,
shall be determined by multiplying the Net Sales (as defined above) of the
combination product by the fraction, A/(A+B) where A is the average sale price
of the Shared Product or Independent Product when sold separately in finished
form and B is the average sale price of the other product(s) or system sold
separately in finished form or where A+B is the average sale price of the
product(s) and the delivery system together, as the case may be. In the event
that such average sale price cannot be determined for both the product and such
other product(s) or system in combination, Net Sales for purposes of determining
royalty payments shall be calculated by multiplying the Net Sales of the
combination products by the fraction C/(C+D) where C is the party's Cost of
Goods of the Shared Product or Independent Product and D is the party's cost of
goods for the other product(s) or system, determined in accordance with the
method of accounting normally employed by such party in computing cost of goods.

      OTHER ALLOWABLE EXPENSES means any costs incurred by the parties (i) in
obtaining and enforcing intellectual property rights relating to Shared
Products, included in the NeoGenesis Patent Rights, Immusol Patent Rights,
NeoGenesis Intellectual Property, Immusol Intellectual Property, Program Patent
Rights and Program Intellectual Property, (ii) in defending against any third
party claim of infringement of such third party's intellectual property rights
or of property damage or injury or death to persons arising out of or relating
to the Manufacturing, use, sale, offer for sale or import of Shared Products and
(iii) as set forth in Section 3.25.

      OVERHEAD shall mean facilities costs (including rent, depreciation,
utilities, insurance, taxes, repairs and maintenance), freight and
communications expenses, supervisory costs and costs of administrative support,
but shall not include General Corporate Overhead. In the event that such costs
cannot be calculated on a Designated Shared Compound-by-

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Designated Shared Compound or Shared Product-by-Shared Product basis, such costs
shall be calculated by multiplying: (i) the aggregate overhead incurred by the
party's pharmaceutical business for all pharmaceutical products that shall be
calculated correspondingly according to the formula set forth in this paragraph;
by (ii) a fraction, (x) the numerator of which is the Net Sales for such Shared
Product; and (y) the denominator of which is the total net sales of all
pharmaceutical products of the party's pharmaceutical business that shall be
calculated correspondingly according to the formula for Net Sales under this
Agreement.

      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,
other than NeoGenesis or Immusol.

      PHASE I CLINICAL TRIALS means any human clinical trials, the principal
purpose of which is a preliminary determination of safety and Pk of a Shared
Product or Independent Product, as the case may be, for its intended use in
healthy individuals or patients to support its continued testing in similar
clinical trials prescribed by the relevant Regulatory Authorities.

      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 of a Shared Product or Independent Product, as the case
may be, in patients with the disease target being studied as required by the
relevant Regulatory Authorities.

      PHASE III CLINICAL TRIALS means any safety and/or efficacy clinical
studies of any Shared Product or Independent Product, as the case may be, in
human patients with the disease target being studied to determine safety and
efficacy of such Shared Product or Independent Product, as the case may be, in
patients as required by the relevant Regulatory Authorities.

      POST-REGULATORY APPROVAL CLINICAL STUDIES EXPENSES means the cost of
conducting clinical trials conducted after Regulatory Approval of Shared
Products in a country, costs of monitoring adverse drug reactions, cost of
handling quality control complaints, costs associated with maintaining the
regulatory approval of Shared Products and reasonably allocable regulatory
affairs group overhead costs.

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      PRE-CLINICAL DEVELOPMENT means all aspects of all activities (including,
but not limited to: medicinal chemistry, cytotoxicity and target specificity,
chemical development/scale-up; formulation; stability; non-GLP, GLP, acute and
chronic toxicity studies; pharmacokinetics; absorption, distribution, metabolism
and excretion (ADME) studies; and safety pharmacology) that will be undertaken
with respect to a Designated Shared Compound or Independent Compound or
Derivative Compound thereof, as the case may be, that are necessary or desirable
to enable the filing of an IND for a Shared Product or Independent Product based
upon or incorporating such Designated Shared Compound or Independent Compound or
Derivative Compound thereof, including the preparation and filing of an IND.

      PRE-LAUNCH EXPENSES means direct costs, specifically allocable to the
Shared Products, incurred prior to commencement of sales of the Shared Products
including advertising, education, sales force training, Phase IIIb clinical
trials, trademark selection, filing and enforcement costs and includes the
Marketing, Advertising and Education Expenses.

      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.

      PROGRAM means the Screening Program and the activities undertaken
pursuant to Section 3 with respect to Designated Shared Compounds, Derivative
Compounds thereof, Shared Products, Independent Compounds, Derivative Compounds
thereof and Independent Products.

      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 Immusol 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 Immusol at any time if such Inventions are based upon or related
to the performance of the Program. Program Intellectual Property will be listed
in ATTACHMENT B, which shall be amended from time-to-time to include new Program
Intellectual Property, in accordance with Section 4.3.

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

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

      RECALL EXPENSES means expenses associated with any Shared Product
recall or any FDA (or its foreign equivalent) mandated communication relating to
a potential recall of any Shared Product.

      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 Shared
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.

      SCREENING PROGRAM means the screening program described in paragraphs
1-10 of ATTACHMENT A as the same may be amended by mutual written agreement of
the parties acting through the Steering Committee; but subject to the limitation
specified in Section 2.5(b)(i).

      SELLING AND PROMOTION EXPENSES means direct costs, specifically
allocable to a Shared Product, incurred for the sale (including costs of sales
forces, sales force incentives specific to a Shared Product, customer targeting,
call reporting and other monitoring/tracking costs, training of sales force and
other regional sales management) and the promotion (including costs of
promotional literature, symposia, industry trade shows, exhibits and direct
mail) of a Shared Product and which are not also characterized as Marketing,
Advertising and Education Expenses. In the event that such costs cannot be
calculated on a Shared Product-by-Shared Product basis, such costs shall be
calculated by multiplying: (i) the aggregate selling and promotion expenses
incurred by the party's pharmaceutical business for all pharmaceutical products
that shall be calculated correspondingly according to the formula set forth in
this paragraph; by (ii) a fraction, (x) the numerator of which is the

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Net Sales for such Shared Product; and (y) the denominator of which is the total
net sales of all pharmaceutical products of the party's pharmaceutical business
that shall be calculated correspondingly according to the formula for Net Sales
under this Agreement.

      SHARED PRODUCT(S) means any product made up of, comprising or containing a
Designated Shared Compound or a Derivative Compound thereof.

      SHARED PRODUCT LOSSES means in any calendar year the excess, if any, by
which Expenses exceed Net Sales.

      SHARED PRODUCT PROFITS means in any calendar year the excess, if any, by
which Net Sales exceed Expenses.

      SHARED TARGETS means a specific protein target proposed by Immusol and
approved by NeoGenesis for which NeoGenesis will perform the Screening Program
and for which NeoGenesis and Immusol shall contribute equally to the further
research, Pre-Clinical Development and Development of compounds active against
Shared Targets, and all costs related to such activities in respect of such
Shared Targets, and NeoGenesis and Immusol shall share equally in the proceeds
of any resulting product(s), as described in Section 3. An Excluded Target is
not a Shared Target for purposes of this Agreement until such time, if any,
as it becomes a Shared Target in accordance with the procedure specified in
section 2.1.

      SUBLICENSE REVENUE means revenues or other consideration received from
such sublicensee as consideration for the grant of such sublicense, less the
expenses directly attributable to supplying goods and services to such
sublicensees to enable their practice of such sublicenses (excluding all amounts
received for the purchase of an equity interest in, or as a loan to, a party, in
each case at the fair market value thereof.)

      TERRITORY means all the countries of the world.

      THIRD PARTY ROYALTIES means any consideration approved by the Steering
Committee and paid to third parties pursuant to Section 3.13.

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

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     AGREEMENT                                                     Recitals
     BANKRUPTCY CODE                                               Section 4.1
     DESIGNATED SHARED COMPOUND(S)                                 Section 3.2
     DEVELOPMENT BUDGET                                            Section 3.7
     DEVELOPMENT PLAN                                              Section 3.7
     DISCONTINUED COMPOUND(S)                                      Section 3.3
     DISCRETE COMPOUND(S)                                          ATTACHMENT A
                                                                   ---------- -
     DISPUTE NOTICE                                                Section 9.1
     EFFECTIVE DATE                                                Recitals
     EXCLUDED TARGET                                               Section 2.1
     FINAL TARGET REPORT                                           ATTACHMENT A
                                                                   ---------- -
     IMMUSOL                                                       Recitals
     INDEMNIFIED PARTY(IES)                                        Section 7.2
     INDEMNIFYING PARTY                                            Section 7.2
     INDEPENDENT COMPOUND(S)                                       Section 3.15
     INDEPENDENT PARRY                                             Section 3.15
     INDEPENDENT PRODUCT                                           Section 3.15
     LOSSES                                                        Section 7.2
     MARKETING BUDGET                                              Section 3.24
     MARKETING PLAN                                                Section 3.24
     NEOGENESIS                                                    Recitals
     NON-PROPOSED COMPOUND(S)                                      Section 3.4
     NON-PROPOSED COMPOUND
     INTERESTED PARTY                                              Section 3.4
     OVERAGE THRESHOLD                                             Section 3.8
     PRELIMINARY COMPOUND(S)                                       ATTACHMENT A
                                                                   ---------- -
     PRIMARY ACTIVE COMPOUND(S)                                    ATTACHMENT A
                                                                   ---------- -
     RE-ENGAGEMENT AMOUNT                                          Section 3.16
     RE-ENGAGEMENT EXPIRATION DATE                                 Section 3.16
     RE-ENGAGEMENT NOTICE                                          Section 3.16
     SELECTED SHARED COMPOUND(S)                                   ATTACHMENT A
                                                                   ---------- -
     SHARE OF LOSS                                                 Section 3.17
     SHARE OF PROFIT                                               Section 3.17
     STEERING COMMITTEE                                            Section 2.5
     TERMINATED COUNTRIES                                          Section 3.24

2.   TARGET SELECTION; SCREENING PROGRAM
2.1 DISCLOSURE OF TARGETS. During the Program, Immusol shall from time to time
disclose to NeoGenesis in writing specific protein targets and propose that such
targets become Shared Targets. Immusol will disclose to NeoGenesis a minimum of
[*] proposed Shared Targets during the first year

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SEPARATELY WITH THE COMMISSION.

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of the Screening Program; [*] proposed Shared Targets during the second year of
the Screening Program and [*] proposed Shared Targets during the third year of
the Screening Program and Immusol may disclose [*] proposed Shared Targets per
year during the term of the Screening Program, or a larger number if mutually
agreed upon by the parties. Within [*] of each disclosure of a proposed Shared
Target by Immusol, NeoGenesis shall notify Immusol in writing whether such
proposed Shared Target is an Excluded Target (as defined below). If NeoGenesis
does not serve such notice within the specified period, such proposed Shared
Target shall not be an Excluded Target and shall be deemed a Shared Target.
NeoGenesis may deem a proposed Shared Target as an Excluded Target if on the
date NeoGenesis receives such proposed Shared Target disclosure from Immusol:
(a) NeoGenesis is prohibited from performing the screening contemplated in this
Agreement on such proposed Shared Target pursuant to the terms of a contract
previously entered into with a third party, (b) NeoGenesis has received a
request from a third party to provide screening on such proposed Shared Target
and NeoGenesis reasonably expects to commence such screening within [*] for such
third party, or (c) NeoGenesis has previously conducted screening on such
proposed Shared Target for another party (each, an EXCLUDED TARGET). Excluded
Targets shall count toward the minimum number of proposed Shared Targets to be
proposed by Immusol during the applicable period of the Screening Program. Such
Excluded Targets [*] towards the maximum of number of Shared Targets to be
proposed by Immusol during the applicable period of the Screening Program.
NeoGenesis will promptly notify Immusol if an Excluded Target that was excluded
pursuant to Section 2.1 (b) does not become the subject of screening at
NeoGenesis within said [*] period Immusol may have such Excluded Target deemed a
Shared Target with notice to NeoGenesis.

2.2  DELIVERY OF TARGET PROTEINS; COMMENCEMENT OF SCREENING PROGRAM. (a) Immusol
shall deliver to NeoGenesis for screening each Shared Target within [*]
following designation of such Shared Target in accordance with section 2.1.
Immusol shall provide Shared Targets in the quantities and formats specified in
ATTACHMENT A. Immusol shall also provide NeoGenesis at the time of delivery with
a written description of the concentration and volume of the Target. Immusol
shall deliver the Targets FOB to NeoGenesis' Cambridge, Massachusetts facility.

     (b) With respect to each Shared Target delivered by Immusol, NeoGenesis
will initiate screening as described in ATTACHMENT A within [*] following the
date of receipt of such Shared Target and complete such screening obligations
within [*] following the date of receipt of such Shared

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Target, unless the parties agree in writing to extend the period for
performance.

2.3  GRANT OF RESEARCH LICENSES. (a) Immusol hereby grants NeoGenesis a
nonexclusive, nontransferable, royalty-free license to use Immusol Intellectual
Property and Program Intellectual Property owned by Immusol (including Immusol
Patent Rights) solely for purposes of conducting the Screening Program and
performing NeoGenesis' obligations under the Screening Program. NeoGenesis will
not use Immusol Intellectual Property and Program Intellectual Property owned by
Immusol for any other purpose, without Immusol's prior written permission and
except as otherwise permitted by the licenses granted in Section 4.1. NeoGenesis
shall not (i) grant, or attempt to grant, a sublicense under this Section 2.3 to
use Immusol Intellectual Property or Program Intellectual Property owned by
Immusol to any Person without the express written consent of Immusol or (ii)
modify the Targets supplied by Immusol, including, without limitation, the
making of any derivatives, analogs, fragments or components thereof. In the
event that NeoGenesis does not consume all of the Targets supplied by Immusol in
performance of the Screening Program, NeoGenesis will upon completion of the
Screening Program with respect to each particular Target, return to Immusol any
quantities of such Target and any derivatives, analogs, fragments or components
thereof.

     (b) NeoGenesis hereby grants Immusol a nonexclusive, nontransferable,
royalty-free license to use NeoGenesis Intellectual Property and Program
Intellectual Property owned by NeoGenesis (including NeoGenesis Patent Rights)
solely for purposes of conducting the Screening Program and performing Immusol's
obligations under the Screening Program. Immusol will not use NeoGenesis
Intellectual Property and Program Intellectual Property owned by NeoGenesis for
any other purpose, without NeoGenesis' prior written permission and except as
otherwise permitted by the licenses granted in Section 4.1. Immusol shall not
grant, or attempt to grant, a sublicense under this Section 2.3 to use
NeoGenesis Intellectual Property or Program Intellectual Property owned by
NeoGenesis to any Person without the express written consent of NeoGenesis. In
addition, Immusol shall not analyze the structure of any Preliminary Compounds,
Discrete Compounds or Primary Active Compounds or otherwise seek to derive,
independent of NeoGenesis, the structure of such Preliminary Compounds, Discrete
Compounds or Primary Active Compounds until such time as the parties designate

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Primary Active Compounds as Selected Shared Compounds in accordance with the
procedure specified in ATTACHMENT A.

2.4  SCIENTIFIC REPORTS. (a) NeoGenesis will keep and maintain adequate records
containing laboratory data generated in the course of the Screening Program to
enable it to furnish complete and accurate information to Immusol regarding the
Screening Program activities and results, including all Program Intellectual
Property described in clauses (a) or (b) of the Program Intellectual Property
definition. All such written records of NeoGenesis shall be open to inspection
by Immusol during normal business hours upon reasonable prior notice.

     (b) NeoGenesis shall provide Immusol with reasonably-detailed written
reports describing the results of the research performed pursuant to the
Screening Program including all Program Intellectual Property described in
clauses (a) or (b) of the Program Intellectual Property definition. Such reports
shall be delivered to Immusol at least quarterly during the Screening Program.
Representatives of NeoGenesis will make themselves reasonably available to
discuss such reports and the progress of the Screening Program. NeoGenesis will
deliver a Final Target Report (as defined in ATTACHMENT A) with respect to the
Screening Program work performed on each Shared Target.

2.5  STEERING COMMITTEE. (a) A Steering Committee (STEERING COMMITTEE) shall be
responsible for oversight of the Program, including the Screening Program. The
Steering Committee shall consist of four (4) members, two (2) members to be
appointed by each of NeoGenesis and Immusol, except as otherwise provided in
Section 3.7. Each party shall appoint a senior scientist and a senior business
executive as its Steering Committee members Each party may, with notice to the
other, substitute any of its members serving on the Steering Committee. The
initial Immusol members shall be Jack Barber and Niv Caviar and the initial
NeoGenesis members shall be Satish Jindal and Huw Nash. Immusol shall have the
right to appoint one of its members to be the chairperson of the Steering
Committee. Either party may send up to three (3) additional employees to attend
Steering Committee meetings, with at least three (3) days notice to the other
party; PROVIDED that such attendees shall be non-voting observers at such
meetings.

     (b) The Steering Committee shall be responsible for the management and
conduct of the Program, including the Screening Program, and shall in
particular: (i) consider, review and amend ATTACHMENT A from

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time to time in such manner as may be appropriate; PROVIDED, that the Steering
Committee may not amend ATTACHMENT A in a manner that would conflict with the
time period for designating Designated Shared Compounds specified in Section 3.1
or the obligations specified in the last sentence of Section 2.3(b), in each
case without the prior written agreement of both Immusol and NeoGenesis; (ii)
monitor progress of the Program; (iii) report regularly to the management of
both parties upon the progress of the Program; (iv) be the conduit for transfer
of information between the parties; and (v) conduct such other activities as set
forth in Section 3.

     (c) The Steering Committee shall hold meetings as mutually agreed by the
parties (but in no event less frequently than twice a year during the term of
the Screening Program, unless mutually agreed by the parties) 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,
Massachusetts. Thereafter, meetings may be held by telephone or video
conference, PROVIDED THAT the parties shall meet in person at least once a year
during the Screening Program.

     (d) Minutes of all meetings setting forth decisions of the Steering
Committee relative to the Program shall be prepared by the host party and
circulated to both parties within twenty five (25) 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).

     (e) The quorum for Steering Committee meetings shall be two (2) members,
provided there is at least one member from each of NeoGenesis and Immusol
present. 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 thirty (30) days after the date on
which the disagreement arose, the matter shall be referred to Immusol's Chief
Executive Officer and NeoGenesis' Chief Executive Officer or their respective
designees. Thereafter, if any such disagreement is not resolved within forty
five (45) days: (i) if such disagreement concerns medicinal chemistry matters
then NeoGenesis will have the right to make the final decision; (ii) if such
disagreement concerns clinical trial matters then Immusol will have the right to
make the final decision; and (iii) if such disagreement concerns any other
matter the parties shall propose and discuss in good faith additional dispute
resolution mechanisms; UNLESS in

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each case it is otherwise expressly provided in Section 3 that a particular
decision of the Steering Committee shall be unanimous.

2.6  EXCLUSIVITY. (a) NeoGenesis shall not screen any Shared Targets screened by
NeoGenesis on behalf of Immusol during the Screening Program for a third party
or internally at NeoGenesis (nor shall NeoGenesis research, develop, make, use
or sell any products active against such Shared Targets) during the Screening
Program and for a period of [*] following completion of all work by NeoGenesis
under the Screening Program with respect to such Shared Target. Notwithstanding
the foregoing, NeoGenesis shall not screen any Shared Target proprietary to
Immusol: (i) for a third party, except upon the request of such third party and
not as a result of any solicitation by NeoGenesis with respect to any Shared
Target, for a period of [*] following completion of all work by NeoGenesis under
the Screening Program with respect to such Shared Target; or (ii) internally at
NeoGenesis for a period of [*] following completion of all work by NeoGenesis
under the Screening Program with respect to such Shared Target. In addition,
NeoGenesis will not screen any Shared Target with respect to which the parties
have elected a Designated Shared Compound pursuant to Section 3.1.

     (b) Subject to its obligations under this Section 2, nothing in the
Agreement shall be construed to prohibit Immusol, alone or with third parties,
from performing screening for compounds active against Shared Targets; PROVIDED,
that: (i) [*] during the Screening Program and until the date for each party's
election of Designated Shared Compounds with respect to such Shared Target; and
(ii) no NeoGenesis Intellectual Property or Program Intellectual Property owned
by NeoGenesis is used in the development of such products.

3.   DEVELOPMENT AND COMMERCIALIZATION OF SHARED COMPOUNDS
3.1  IDENTIFICATION OF DESIGNATED SHARED COMPOUND CANDIDATES BY STEERING
COMMITTEE. (a) Within [*] following the delivery of Selected Shared Compounds
for a particular Shared Target in accordance with ATTACHMENT A and completion of
optimization, if any, performed on Selected Shared Compounds for such Shared
Target in accordance with ATTACHMENT A (which optimization shall be completed
within the [*] period following delivery of Selected Shared Compounds for a
particular Shared Target), either party may propose to the Steering Committee
one or more Selected Shared Compounds or compounds arising out of optimization
(if any) for such Shared Target as candidates to become Designated Shared

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Compounds. The Steering Committee will promptly determine whether each such
proposed Designated Shared Compound is a suitable candidate for Pre-Clinical
Development.

     (b) Within [*] following receipt of notification from the Steering
Committee identifying candidates to become Designated Shared Compounds,
NeoGenesis shall amend ATTACHMENT D to identify any applicable NeoGenesis Patent
Rights not previously identified to the Steering Committee.

3.2  ACCEPTANCE OF DESIGNATED SHARED COMPOUNDS. (a) If the Steering Committee
determines that a Selected Shared Compound is suitable for Pre-Clinical
Development, then, within [*] of such determination, each party shall provide to
the Steering Committee a written notice as to whether it elects to participate
in and, subject to Section 3.8, commit resources to conduct, Pre-Clinical
Development and, if warranted based on the outcome of Pre-Clinical Development
activities, Development of such Selected Shared Compound pursuant to the
Development Plan and Development Budget. If both parties make an affirmative
election with respect to any Selected Shared Compound pursuant to this Section
3.2, then such Selected Shared Compound shall become a DESIGNATED SHARED
COMPOUND. Thereafter, such Designated Shared Compound will be subject to the
licenses granted pursuant to Section 4.1 and shall no longer be available to
NeoGenesis or any third party in any NeoGenesis compound library, including its
NeoMorph Screening Library.

     (b) If the Steering Committee determines that a Selected Shared Compound is
not suitable for Pre-Clinical Development, then, within [*] of such
determination, each party shall provide to the Steering Committee a written
notice as to whether it elects to designate such Selected Shared Compound as a
Designated Shared Compound and participate in, and commit resources to conduct
Pre-Clinical Development of such Selected Shared Compound, notwithstanding that
the Steering Committee has determined that such Selected Shared Compound is not
suitable for Pre-Clinical Development. If both parties make an affirmative
election with respect to whether any Selected Shared Compound shall be
designated a Designated Shared Compound as set forth in Section 3.2(a), such
Selected Shared Compound shall become a Designated Shared Compound. If one party
makes an affirmative election and the other party makes a negative election with
respect to whether any Selected Shared Compound shall be designated a Designated
Shared Compound, the party making an

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affirmative election will have the right to proceed independently to develop
such compound as an Independent Compound or Independent Product under Section
3.15.

3.3  DISCONTINUED COMPOUNDS. If neither party makes an affirmative election with
respect to any Selected Shared Compound being designated a Designated Shared
Compound pursuant to Section 3.2, such Selected Shared Compound shall be neither
a Designated Shared Compound nor a compound that may be developed under Section
3.15, and Development of products based upon such non-elected Selected Shared
Compound (a DISCONTINUED COMPOUND) may only be subsequently initiated by a party
by notifying the other party of its interest in initiating Pre-Clinical
Development of such Discontinued Compound at any time on or before the date of
termination or expiration of this Agreement. If a party provides such notice and
the other party indicates it is not interested in participating in, and
committing resources to, conduct Pre-Clinical Development of such Discontinued
Compound, the initiating party, upon notice to the other party, may proceed with
Pre-Clinical Development and Development of such Discontinued Compound as an
Independent Compound or an Independent Product and the initiating party shall be
deemed to be the Independent Party therefor, as provided in Section 3.15. If the
other party indicates it is interested in participating in and committing
resources to conduct Pre-Clinical Development of such Discontinued Compound,
such Discontinued Compound shall be designated as a Designated Shared Compound
as set forth in Section 3.2(a). At any time after the date of termination or
expiration of this Agreement, either party may, upon written notice to the
other party, proceed with Pre-Clinical Development and Development of a
Discontinued Compound as an Independent Compound or an Independent Product, and
such party shall be deemed to be the Independent Party therefor, as provided in
Section 3.15.

3.4  NON-PROPOSED COMPOUNDS. If a Selected Shared Compound is not, at any time,
presented to the Steering Committee pursuant to Section 3.1 (a NON-PROPOSED
COMPOUND), such Selected Shared Compound shall be neither a Designated Shared
Compound nor a compound that may be developed under Section 3.15. If at any time
on or before the date of termination or expiration of this Agreement, a party
hereunder (the NON-PROPOSED COMPOUND INTERESTED PARTY) decides to initiate
Pre-Clinical Development of such Non-Proposed Compound, it shall provide written
notice to the other party of such interest and the reasons therefor. The other
party will then have ninety (90) days to

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indicate whether it also is interested in participating in and committing
resources to conduct Pre-Clinical Development of such Non-Proposed Compound. If
the other party is so interested, such Non-Proposed Compound shall be designated
a Designated Shared Compound as set forth in Section 3.2(a). If the other party
is not so interested, the Non-Proposed Compound Interested Party may proceed
with Pre-Clinical Development and Development of such Non-Proposed Compound as
an Independent Compound or an Independent Product and the Non-Proposed Compound
Interested Party shall be deemed to be the Independent Party therefor, as
provided in Section 3.15. At any time after the date of termination or
expiration of this Agreement, either party may, upon written notice to the
other party, proceed with Pre-Clinical Development and Development of a
Non-Proposed Compound as an Independent Compound or an Independent Product, and
such party shall be deemed to be the Independent Party therefor, as provided in
Section 3.15.

3.5  PRE-CLINICAL DEVELOPMENT OF DESIGNATED SHARED COMPOUNDS. The parties, under
the direction of the Steering Committee, shall diligently conduct Pre-Clinical
Development with respect to any Designated Shared Compound in accordance with
the Development Plan. Unless otherwise agreed by the parties, each party shall
supply fifty percent (50%) of the total Pre-Clinical Development effort for each
Designated Shared Compound in the aggregate, as determined by the Steering
Committee. The costs of conducting such Pre-Clinical Development shall be shared
by the parties as set forth in Section 3.8.

3.6  DEVELOPMENT OF SHARED PRODUCTS. The parties will use Commercially
Reasonable Efforts to conduct the Development of Shared Products in accordance
with the Development Plan. The role of each party in the Development process
will be determined by the Steering Committee as described in Section 3.7, with
the parties intending that each party will provide advisory and supporting
services with respect to any phase of the process in which such party is not
actively or primarily involved. Unless otherwise agreed by the parties, each
party shall supply fifty percent (50%) of the total Development effort for each
Shared Product in the aggregate, as determined by the Steering Committee. The
costs of conducting such Development shall be shared by the parties as set forth
in Section 3.8. The Steering Committee will determine appropriate written
standards for measuring each party's required efforts and accounting procedures
to confirm and document each party's performance of its required efforts for any
Shared Product before the parties commence Development thereof. No clinical
trials involving any Shared Product shall be commenced by or on

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behalf of either party without the prior approval of the Steering Committee.
Nothing contained in this Section 3.6 shall be deemed to preclude either party
from terminating its participation in the collaborative Development of a Shared
Product pursuant to Section 3.14. Any decision by a party not to participate in
Development of a Shared Product pursuant to Section 3.2, 3.3 or 3.4 or to
terminate participation in the Development of a Shared Product pursuant to
Section 3.14, shall not be deemed a breach of this Agreement. The parties will
conduct Pre-Clinical Development, Development, Manufacturing and
Commercialization activities in a manner calculated to minimize aggregate
Development Costs for such Shared Compound and Shared Product consistent with
the Development Plan and the Development Budget for such Shared Compound and
Shared Product.

3.7  DEVELOPMENT PLAN AND DEVELOPMENT BUDGET. Promptly following acceptance of a
Designated Shared Compound, the Steering Committee, which, for this purpose and
for the purposes set forth in Sections 3.8-3.10 and 3.23, shall also include an
equal number of financial personnel from each party, shall initiate preparation
of the development plan for the Pre-Clinical Development and Development of such
Designated Shared Compound and Development of any resulting Shared Product (the
DEVELOPMENT PLAN) and a budget (the DEVELOPMENT BUDGET) for proposed Development
Costs therefor. The initial Development Plan for a Designated Shared Compound
shall set time lines and priorities for the various Pre-Clinical Development and
Development activities through Phase I Clinical Trials or Phase IIa Clinical
Trials and identify which party, or whether a third party, is to be responsible
for each activity. The Development Budget shall include a detailed short-term
budget covering all proposed Development Costs of the Development Plan expected
during the initial two (2) years of implementation of the Development Plan. Each
Development Plan and Development Budget shall be approved by the Steering
Committee unanimously. Both parties recognize that the Development Plan and the
Development Budget represent projections only and will be subject to frequent
changes during the Pre-Clinical Development and Development process. Each such
Development Plan and Development Budget shall be updated as deemed appropriate
by the Steering Committee, but in no event less frequently than semi-annually,
and approved, unanimously, by the Steering Committee not later than thirty (30)
days prior to each January 1 and July 1 of each applicable calendar year.

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3.8  FUNDING OF PRE-CLINICAL DEVELOPMENT AND DEVELOPMENT. Immusol and NeoGenesis
shall each be responsible for fifty percent (50%) of the Development Costs for
each Designated Shared Compound, Derivative Compound thereof and resulting
Shared Product throughout the Territory. In the event the Development Costs
incurred by a party during any calendar quarter exceed [*] of the Development
Costs set forth in the most recently approved Development Budget for activities
to be conducted by such party during such quarter (the OVERAGE THRESHOLD), then
the other party shall not be responsible for paying its fifty percent (50%)
share of any Development Costs in excess of the Overage Threshold incurred by
the party triggering such overage unless such overage had been approved in
advance, or is subsequently ratified, unanimously, by the Steering Committee (in
which case each of the parties shall be responsible for fifty percent (50%) of
all such Development Costs). In the event such overage has not been approved or
ratified unanimously by the Steering Committee, the party incurring Development
Costs in a calendar quarter exceeding the Overage Threshold in such quarter
shall be responsible for all of the portion of the Development Costs in excess
of the Overage Threshold.

3.9  FTE RATE. In preparing the Development Budget and determining Development
Costs, each party will use an FTE rate for such party's development personnel
mutually agreed to by the parties based on the then prevailing FTE rate for such
party.

3.10  PAYMENT OF DEVELOPMENT COSTS. Within thirty (30) days after each calendar
quarter, each party shall provide the Steering Committee with detailed
information concerning the Development Costs incurred by such party during such
quarter pursuant to the Development Plan and the Development Budget. Promptly
after receipt thereof, the Steering Committee will determine the amount, if any,
that either party has paid in excess of the amount to be borne by such party for
such quarter pursuant to Section 3.8, and shall so notify the parties. In the
event of an overpayment by a party of its share of Development Costs in a
particular calendar quarter, the other party shall pay to the party making the
overpayment the amount by which such other party underpaid within thirty (30)
days after the underpaying party's receipt of notice from the Steering Committee
that an overpayment has occurred.

3.11  REGULATORY APPROVALS. Consistent with the Development Plan and Development
Budget and as directed by the Steering Committee, the parties (or their
Affiliates) will (a) prepare and file all documents that are necessary to
conduct clinical studies of Shared Products in connection with the

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Development Plan and (b) use Commercially Reasonable Efforts to file
applications for Regulatory Approvals required before commercial sale or use of
a Shared Product as a drug in a country within the Territory and obtain
Regulatory Approvals in each country in the Territory in which the parties,
either individually or jointly, intend to Commercialize Shared Products in
accordance with the Development Plan. The Steering Committee will be responsible
for designating a party by unanimous agreement to be responsible for filing all
regulatory submissions in each country in the Territory in which Shared Products
will be Commercialized. The party not responsible for filing regulatory
submissions for a Shared Product in a country pursuant to this Agreement shall
have a right to cross-reference to all such filings made by the other party for
such Shared Product in any country. The parties will cooperate in the
preparation of all such regulatory filings and in obtaining Regulatory Approvals
under this Section 3.11, including without limitation providing access to each
party's data and information obtained under the Program and the Development Plan
to the extent necessary for obtaining Regulatory Approvals of Shared Products.

3.12  LINE EXTENSIONS. NeoGenesis and Immusol may each prepare and submit to the
Steering Committee for consideration plans for Development of Shared Product
line extensions and the conduct of clinical trials covering indications other
than those for which Shared Products are then being Developed or Commercialized
in the Territory. Any such line extensions or any additional clinical trials for
additional indications will be subject to the approval and supervision of the
Steering Committee as part of the ongoing Development of such Shared Product.

3.13  THIRD PARTY TECHNOLOGY; CONSENTS TO CERTAIN SUBLICENSES. If either party
becomes aware of (a) an opportunity to participate in research with a third
party that could advance the Pre-Clinical Development of a Designated Shared
Compound or Derivative Compound thereof or the Development of a Shared Product;
or (b) an opportunity to obtain a license or other right owned or controlled by
a third party relating to the Manufacture, marketing, import, use or sale of a
Shared Product, it shall so notify the other party and the Steering Committee
will determine whether to pursue such opportunity. In the event that the parties
pursue such opportunity under Section 3.13(a), they shall grant appropriate
licenses or sublicenses, as applicable, to such third party solely to perform
the tasks designated and approved by the Steering Committee for such third party
and provide for confidentiality and non-use obligations, and for ownership of or
licenses under such third party's inventions and related intellectual property
rights arising in the course of work performed by such third party

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

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pursuant to this Agreement consistent with those provided in the applicable
provisions of this Agreement. If the parties, in connection with any opportunity
described in subsection (a) or (b), incur obligations to make payments to a
third party, such payments shall be included in the calculation of Expenses or
Development Costs, as the case may be, of the party making such payment. Neither
party shall enter into any sublicense under which such party shall receive any
consideration from the relevant sublicensee in the form of an equity investment
in, or as a loan to, such party without the other party's prior written consent,
not to be unreasonably withheld.

3.14  TERMINATION OF PARTICIPATION IN COLLABORATIVE DEVELOPMENT. (a) Either
party may elect, on a Designated Shared Compound-by-Designated Shared Compound,
Derivative Compound thereof-by-Derivative Compound thereof or Shared
Product-by-Shared Product basis, as the case may be, to terminate its
participation in, or to not participate in, the Pre-Clinical Development of a
given Designated Shared Compound or Derivative Compound thereof or Development
of a given Shared Product based upon or incorporating such Designated Shared
Compound or Derivative Compound thereof by written notice to the other party:
(i) at any time prior to expiration of the forty five (45) day period following
such party's receipt of final copies of all material documents to be filed with
the FDA or equivalent Regulatory Authority as part of an IND submission for such
Designated Shared Compound or Derivative Compound thereof, (ii) during the
period commencing upon receipt by such party of final reports covering all
aspects of completed Phase I Clinical Trials for such Shared Product and ending
forty five (45) days thereafter; or (iii) during the period commencing upon
receipt by such party of final reports covering all aspects of completed Phase
II Clinical Trials for such Shared Product and ending forty five (45) days
thereafter. After receipt of such notice by the other party in accordance with
this Section 3.14, the party providing such notice shall no longer be
responsible for bearing further Development Costs for such Designated Shared
Compound or Derivative Compound thereof or Shared Product pursuant to Section
3.8 (except as set forth in the next succeeding sentence), in which event the
other party will have the right to proceed independently to Develop such
Designated Shared Compound or Derivative Compound thereof or Shared Product as
an Independent Compound or Independent Product, and the party continuing such
Development shall thereafter be deemed to be the Independent Party therefor, as
provided in Section 3.15. In the event a party gives notice under this Section
3.14, such non-Independent Party (i) will remain responsible for its share of
Development Costs for such Designated Shared

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

                                      27
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Compound or Derivative Compound thereof or Shared Product until ninety (90) days
from the date the other party receives such notice, and (ii) will make its
personnel, relevant data and other resources available to the Independent Party
as necessary to effect an orderly transition of Pre-Clinical Development and
Development responsibilities, with the costs of such personnel, relevant data
and resources to be borne by the Independent Party after it receives a notice
under this Section 3.14. In the event of a party's termination of participation
in Pre-Clinical Development or Development of a Designated Shared Compound or
Derivative Compound thereof or Shared Product in accordance with this Section
3.14, such party shall transfer and assign to the Independent Party all
Regulatory Approval submissions, including all applications relating to such
Designated Shared Compound, Derivative Compound thereof and/or Shared Products
based upon or incorporating such Designated Shared Compound or Derivative
Compound thereof, together with all materials and data related thereto in its
possession.

     (b) If, at any time during Pre-Clinical Development or Development
activities, both parties elect, on a Designated Shared Compound-by-Designated
Shared Compound basis, Derivative Compound thereof-by-Derivative Compound
thereof basis or a Shared Product-by-Shared Product basis, as the case may be,
to terminate Pre-Clinical Development of a Designated Shared Compound or
Derivative Compound thereof or to terminate Development of a Shared Product, the
parties shall confer and mutually agree on a plan for seeking a purchaser or
licensee for the Designated Shared Compound, Derivative Compound thereof or
Shared Product, as applicable.

3.15 INDEPENDENT DEVELOPMENT. (a) In the event (i) a party, pursuant to
Sections 3.2, 3.3, 3.4 or 3.14, elects not to, or does not, participate in and
commit resources to the pre-clinical development of a Selected Shared Compound
as a Designated Shared Compound, or the pre-clinical development of a
Discontinued Compound or a Non-Proposed Compound, or (ii) any party unilaterally
terminates its participation in the Pre-Clinical Development or Development of a
Designated Shared Compound, Derivative Compound thereof or Shared Product
pursuant to Section 3.14, then the party that either made an affirmative
election to conduct such Pre-Clinical Development of such Selected Shared
Compound, or the Pre-Clinical Development of a Discontinued Compound or a
Non-Proposed Compound, or is continuing Pre-Clinical Development or Development
of a Designated Shared Compound, Derivative Compound thereof or Shared Product
(in either case, the INDEPENDENT PARTY), shall have the right to

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

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practice the licenses granted in Section 4.1 and to undertake pre-clinical
development of a Selected Shared Compound, Discontinued Compound or Non-Proposed
Compound or to continue Pre-Clinical Development and Development of such
Designated Shared Compound, Derivative Compound thereof or Shared Product
independently as an INDEPENDENT COMPOUND or INDEPENDENT PRODUCT, at its sole
cost and in its sole direction. Subject to reinstatement pursuant to exercise of
its Re-Engagement Option set forth in Section 3.16, the non-Independent Party's
license under Section 4.1 shall be terminated with respect to such Independent
Compound or Independent Product. Neither party may charge the services of its
personnel or any third party to research or develop an Independent Compound,
Derivative Compound thereof or Independent Product to the other party.

     (b) Until the earlier of the Re-Engagement Expiration Date or the date on
which the Independent Party receives a Re-Engagement Notice for an Independent
Compound, Derivative Compound thereof or an Independent Product from the
non-Independent Party, the Independent Party will (i) inform the other party of
all material information developed in its research and development of each
Independent Compound, Derivative Compound thereof or Independent Product; and
(ii) provide the other party a copy of all proposed regulatory submissions
relating to such Independent Compound, Derivative Compound thereof or
Independent Product at least thirty (30) days prior to submitting such filing to
the applicable Regulatory Authority.

     (c) In the event either party elects to proceed as an Independent Party,
subject to Section 3.16, such Independent Party shall be entitled to develop
such Independent Compound or any Derivative Compound thereof and Commercialize
such Independent Product at its sole discretion, alone or with a third party
(subject to Section 3.15(d)), with no obligation to the other party other than
the payment of royalties in accordance with Sections 3.18 or 3.19 and those
obligations imposed under Sections 3.20 and 3.22.

     (d) The Independent Party may not sublicense any intellectual property
rights to the extent such right is necessary or useful to research, Develop,
have Developed, make, have made, use, distribute, promote, market, offer for
sale, sell, have sold, import and export an Independent Compound, Derivative
Compound thereof or Independent Product to any third party without the consent
of the non-Independent Party prior to the Re-Engagement Expiration Date for such
Independent Compound, Derivative Compound thereof or Independent Product.

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
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     (e) If either party terminates its research, Development or
Commercialization of an Independent Compound, Derivative Compound thereof or an
Independent Product, then (i) it shall promptly so notify the other party,
(ii) such compound shall no longer be an Independent Compound, Derivative
Compound thereof and such product shall no longer be an Independent Product;
(iii) the licenses granted to such Independent Party by the non-Independent
party for such compound or product shall terminate upon such other party's
receipt of such notice; and (iv) the parties will confer and mutually agree on a
plan for seeking a purchaser or licensee for such Independent Compound,
Derivative Compound thereof or Independent Product, as applicable.

3.16 RE-ENGAGEMENT OPTION. (a) Either party may elect to resume its
participation in the Pre-Clinical Development or Development of an Independent
Compound, Derivative Compound thereof or Independent Product throughout the
Territory by so notifying the Independent Party for such Independent Compound,
Derivative Compound thereof or Independent Product (the RE-ENGAGEMENT NOTICE),
at any time prior to the expiration of the forty five (45) day period commencing
upon receipt by the non-Independent Party of the final report summarizing the
results of all Phase II Clinical Trials (RE-ENGAGEMENT EXPIRATION DATE) for such
Independent Compound, Derivative Compound thereof or Independent Product. If a
party so elects to resume participation hereunder, such Independent Compound,
Derivative Compound thereof or Independent Product shall immediately cease to be
an Independent Compound, Derivative Compound thereof or Independent Product, as
applicable, and shall instead be designated a Designated Shared Compound or
Shared Product for all purposes under this Agreement, including but not limited
to calculating each party's responsibility for paying Development Costs and
Expenses and receiving the Share of Profit commencing upon and continuing after
the Independent Party's receipt of the Re-Engagement Notice.

         (b) If a party provides a Re-Engagement Notice pursuant to Section
3.16(a), then such party shall pay to the Independent Party [*] of the
non-Independent Party's share, based on the allocation set forth in Section 3.8,
of the costs of Pre-Clinical Development and Development of the Independent
Compound, Derivative Compound thereof or Independent Product incurred by the
Independent Party after the date upon which it commenced Pre-Clinical
Development or Development of such compound or product as an Independent
Compound or Independent Product and prior to the date of the Re-Engagement
Notice, calculated as if such Independent Compound or Derivative Compound
thereof had been a Designated Shared Compound or

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

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such Independent Product had been a Shared Product during such period of
Pre-Clinical Development and Development by the Independent Party therefor (the
RE-ENGAGEMENT AMOUNT). In calculating such amounts, the parties will use the FTE
rate as set forth in Section 3.9. The non-Independent Party shall pay the
Re-Engagement Amount in four (4) equal quarterly installments beginning on the
first day of the calendar quarter following the date upon which the Independent
Party receives the relevant Re-Engagement Notice.

3.17 PROFITS AND LOSSES. Each party's SHARE OF PROFIT shall equal fifty percent
(50%) of all Shared Product Profits for all Shared Products sold in the
Territory, and each party's SHARE OF LOSS shall equal fifty percent (50%) of all
Shared Product Losses for all Shared Products sold in the Territory. Each party
shall be responsible for its Share of Loss and shall be entitled to receive its
Share of Profits. Each party shall also receive fifty percent (50%) of all
Sublicense Revenue in the Territory, which sublicense agreements shall conform
to the requirements of Section 3.13. Shared Product Profits, Shared Product
Losses and Sublicense Revenue shall be determined and paid as set forth in
Section 3.23.

3.18 ROYALTIES ON SALES OF INDEPENDENT PRODUCTS AFTER REVOCATION OF
COMMERCIALIZATION RIGHTS. In the event a party elects to terminate its
participation in the Commercialization of a Shared Product in a country or
countries in the Territory pursuant to Section 3.23(d), the parties shall
negotiate in good faith for a period of ninety (90) days following the
non-terminating party's receipt of such notice to determine the appropriate
royalty to be paid on Net Sales of such Shared Product as an Independent Product
by the other party as an Independent Party in such country or countries. In the
event the parties are unable to agree on the appropriate royalty pursuant to the
immediately preceding sentence, the Independent Party with respect to such
Independent Product shall pay to the other party a royalty on annual Net Sales
of such Independent Product in each such country in the Territory pursuant to
Section 3.19, except that the applicable royalty shall be: [*] of the portion of
aggregate annual Net Sales of such Independent Product in such country that is
[*] of the portion of annual aggregate Net Sales of such Independent Product in
such country that is [*] of the portion of annual aggregate Net Sales of such
Independent Product in such country that is [*]. Such royalty will be payable on
a quarterly basis in respect of each country in which sales of such Shared
Product occur and in which a party has elected to terminate its participation in
the Commercialization of such Shared Product until the expiration of the license
granted to the non-terminating party under Section 4.1 with respect to such

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

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Shared Product. Such royalty is subject to offsets as provided in the last
sentence of Section 3.19.

3.19 ROYALTIES OTHER THAN IN THE EVENT OF REVOCATION OF PROMOTION RIGHTS. Except
as otherwise provided in Section 3.18, the Independent Party will pay the
non-Independent Party, in lieu of any Share of Profits, a royalty on Net Sales
of each Independent Product equal to:
         (a)      [*] of Net Sales of such Independent Product if the
                  non-Independent Party did not participate, or terminates its
                  participation, in the Pre-Clinical Development of the relevant
                  Designated Shared Compound pursuant to Section 3.14 prior to
                  the submission of an IND on such compound;
         (b)      [*] of Net Sales of such Independent Product if the
                  non-Independent Party terminates its participation in the
                  Development of the relevant Designated Shared Compound
                  pursuant to Section 3.14 upon or following the submission of
                  an IND on such Independent Product but prior to the end of the
                  first Phase I Clinical Trial therefor;
         (c)      [*] of Net Sales of such Independent Product if the
                  non-Independent Party terminates participation in the
                  Development of the relevant Shared Product pursuant to Section
                  3.14 upon or following the end of the first Phase I Clinical
                  Trial on such Shared Product; or
         (d)      [*] of Net Sales of such Independent Product if the
                  non-Independent Party terminates participation in the
                  Development of the relevant Shared Product pursuant to Section
                  3.14 upon or following the end of the first Phase II Clinical
                  Trial on such Shared Product.

Such royalty shall be payable on a quarterly basis in respect of each country in
which sales of such Independent Product occur until the expiration of the
license granted the Independent Party under Section 4.1 with respect to such
Independent Product. The Independent Party may offset [*] of any royalties it
must pay to third parties pursuant to any licenses necessary to Manufacture and
Commercialize Independent Products against royalties payable by the Independent
Party to the non-Independent Party; PROVIDED, HOWEVER, that in no event shall
the royalties payable by the Independent Party to the non-Independent Party be
reduced to less than [*] of the amounts that would have otherwise been due under
the percentages set forth in this Section 3.19 or Section 3.18, as applicable.

*=CONFIDENTIAL TREATMENT REQUESTED: MATERIAL HAS BEEN OMITTED AND FILED
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3.20 REMITTANCE. (a) Subject to Section 3.20(c), all payments required under
Sections 3.18 and 3.19 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 all Mondays' exchange rate for buying United States
Dollars set forth in THE WALL STREET JOURNAL for the calendar quarter in which
such sales were made.

     (b) In the event that any payment due either party 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 the prime interest rate reported in the WALL STREET JOURNAL
for the due date, or, if lower, the maximum rate permitted by law, 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 the party to whom
payment is due 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 the party owing a royalty of
any royalties owed in respect of sales in such country is prevented, the party
owing a royalty shall make payment through any lawful means or methods that may
be available as such party shall reasonably determine. If royalties in any
country cannot be remitted within three (3) months after the end of the relevant
royalty period, then the party owing a royalty shall pay the other party in the
local currency of such country by deposit of the relevant royalties in a bank
account in such country designated by the other party.

3.21 TAXES. The burden of paying all withholding or similar taxes that may be
imposed by any governmental authority on royalty and Share of Profit payment
amounts provided in this Section 3 with respect to Shared Products shall be
shared equally by Immusol and NeoGenesis. The burden of paying all withholding
or similar taxes that may be imposed by any governmental authority on royalty
payment amounts provided in this Section 3 with respect to Independent Products
shall be paid by the party receiving such royalty, and the party making such
royalty payment shall make such withholding payments as required and subtract
such

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

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withholding payments from the payments to be made to the other party in respect
of such Independent Products, or, if applicable, the party receiving such
royalty payment will reimburse the other party or its designee(s) for the amount
of such withholding payments that are not subtracted from the payments made to
the party receiving such royalty payment as set forth in this Section 3.21,
within fifteen (15) days of notice from the party making such royalty payment in
respect of Independent Products. The party that makes any such withholding
payment shall provide the other party 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 the party receiving such royalty payment. Withholding payments
made by the party making such royalty payment in respect of Independent Products
pursuant to this Section 3.21 shall be made based upon financial information
provided to such party by the party receiving such royalty payment, and to the
extent that such information is incorrect, the party receiving such royalty
payment 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 the party making such royalty payment is required to pay any such deficiency,
or any fine, assessment or penalty for any such deficiency, the party receiving
such royalty payment shall promptly reimburse it for such payments, within
fifteen (15) days of notice to the party receiving such royalty payment. 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 otherwise been incurred under the provisions
of this Agreement, including this Section 3.21.

3.22 RECORDS AND INSPECTION. (a) NeoGenesis and Immusol and, if applicable,
their respective Affiliates and sublicensees, each shall keep accurate books and
accounts of record (prepared in accordance with GAAP) in connection with the
Pre-Clinical Development, Development, Manufacture and/or Commercialization by
or for such party of all Designated Shared Compounds, Derivative Compounds
thereof, Shared Products, Independent Compounds, Derivative Compounds thereof
and Independent Products in the Territory in sufficient detail to permit
accurate determination of all figures necessary for verification of Development
Costs, royalties, Shared Product Profits, Shared Product Losses, Sublicense
Revenue, Expenses and other compensation required to be paid or expenses
required to be shared hereunder. NeoGenesis and

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

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Immusol shall maintain such records for a period of three (3) years after the
end of the year in which such records were generated.

     (b) Each party and, if applicable, its Affiliates shall, and shall provide
in any agreements with any sublicensees that such sublicensees shall, make such
records available for inspection by an independent certified public accountant,
mutually agreed to by the inspecting party and the party being inspected, during
regular business hours at such place or places where such records are
customarily kept, upon reasonable notice from the inspecting party, to verify
the accuracy of the reports and any compensation required to be paid or expenses
required to be shared hereunder. Such inspection right shall not be exercised
more than once in any calendar year. The inspecting party agrees to hold in
confidence all information concerning payments, expenses and reports, and all
information learned in the course of any inspection, except to the extent
necessary for the inspecting party to reveal such information in order to
enforce its rights under this Agreement in a proceeding in accordance with
Section 9.1 or if disclosure is required by law, regulation or judicial order.
Any person or entity conducting such inspection will agree in writing with the
inspecting party to treat all records reviewed in the course of the inspection
as the Confidential Information of the party being inspected under terms and
conditions no less restrictive than the terms contained in Section 5.2. The
results of each inspection shall be binding on both parties absent mathematical
error. The inspecting party shall pay for such inspections, except that in the
event there is any upward adjustment in aggregate amounts payable for any year
shown by such inspection of more than five percent (5%) of the amount paid, the
party being inspected shall pay for such inspection.

3.23 SHARED PRODUCT REPORTING AND PAYMENTS OF THE PARTIES' SHARE OF PROFIT/LOSS.
(a) Payments and reporting for each Shared Product shall be made as follows.
Within forty five (45) days after the close of each party's accounting year in
which Shared Products are sold, or earlier if possible, each party shall furnish
to the other party a profit and loss statement for such accounting year setting
forth for each country in the Territory in which Shared Products were developed
or sold during such year, Net Sales of each Shared Product, Expenses, Sublicense
Revenue and all data on which the determination of each party's Share of Profit,
Share of Loss or share of Sublicense Revenue was calculated. If either party
owes an amount of Share of Profit or Share of Loss to the other party pursuant
to Section 3.17, then it shall make such payment within thirty (30) days after
receipt of the profit and loss statement, but in no event shall such payment be
due earlier than sixty (60) days after the end of the relevant period.

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

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     (b) For the purposes of calculating Shared Product Profit or Shared Product
Loss for a Shared Product, a given item of cost or expense shall be allocated
only to one category of cost and expense and not to multiple categories. Each
party agrees to determine such costs and expenses hereunder with respect to
Shared Products using its standard accounting procedures, consistently applied,
to the maximum extent practical, as if such Shared Product were a solely owned
product of the party, except as specifically provided in this Agreement. The
parties also recognize that such procedures may change from time to time and
that any such changes may affect the definitions of the elements of the Shared
Product Profit or Shared Product Loss. The parties agree that, where such
changes are economically material to either party, adjustments shall be made to
compensate the affected party in order to preserve the same economics as
reflected under this Agreement under such party's accounting procedures in
effect as of the date on which the activity in question (for example,
Development, marketing or Manufacturing) first commences under this Agreement.
Transfers between a party and its Affiliates (or between such Affiliates) shall
not have effect for purposes of calculating revenues, costs, profits, royalties
or other payments or expenses under this Agreement.

3.24 COMMERCIALIZATION. (a) The Steering Committee shall oversee and implement
all Commercialization activities in the Territory for Shared Products, based on
the principle of maximizing profits from sales of Shared Products. The Steering
Committee shall have the ability to determine whether the objective of
maximizing profits from sales of Shared Products in the Territory is best
achieved through, INTER ALIA, granting sublicenses to a third party or third
parties, creating or entering into joint ventures with third parties or jointly
Commercializing such Shared Products as provided in this Section 3.24. In the
event the Steering Committee determines that the foregoing objective is best
achieved by activities other than as provided in this Section 3.24, the Steering
Committee shall determine by unanimous decision the optimal alternative
structure and the duties, responsibilities and economic parameters for the
parties and third parties in such alternative structure.

     (b) No later than one month after filing of the NDA for a Shared Product,
the Steering Committee shall commence preparation of a marketing plan (MARKETING
PLAN) and a marketing budget (MARKETING BUDGET) for such Shared Product. The
Commercialization of a Shared Product in the Territory will be governed by the
Marketing Plan and Marketing Budget. The Marketing Plan and Marketing Budget
will describe fully, to the extent

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

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<Page>

practicable, the proposed plan for Commercialization of the Shared Product in
each country in which the parties Commercialize Shared Products, including
overall marketing strategy, marketing, sales and promotion efforts to be
performed by each party, market and sales forecasts, pricing, reimbursement and
discounting analysis and estimated launch date, as well as preparation of
advertising and other promotional materials to be used in the promotion of
Shared Products. The Marketing Plan will take into consideration market
conditions, regulatory factors and competition with respect to the Shared
Product. The Marketing Budget will include all projected Expenses for the Shared
Product. The initial Marketing Plan and Marketing Budget shall be completed by
the Steering Committee no later than [*] after the first filing of an NDA (or
its foreign equivalent) for a Shared Product in any country in the Territory.
Each such Marketing Plan and Marketing Budget shall thereafter be updated by the
Steering Committee every [*], or more frequently if agreed by the parties.

     (c) NeoGenesis and Immusol shall have the co-exclusive responsibility for
promoting such Shared Product in the Territory, except as otherwise provided in
Section 3.24(a). Immusol and NeoGenesis shall each diligently perform its
respective obligations under the Marketing Plan and use Commercially Reasonable
Efforts to Commercialize Shared Products in the Territory pursuant to the terms
and conditions hereof. The parties intend that each party shall provide fifty
percent (50%) of the total promotional and marketing effort (including details,
if determined to be an appropriate sales activity for a party by the Steering
Committee) for each Shared Product being Commercialized by the parties in the
Territory, as determined by the Steering Committee. The Steering Committee will
determine appropriate written standards for measuring, and accounting procedures
to confirm and document, each party's marketing and promotional effort under the
Marketing Plan, no later than one month after the filing of the NDA for any
Shared Product. Nothing contained in this Section 3.24 shall be deemed to
preclude either party from relinquishing its right to participate in the
Commercialization of Shared Products in the Territory pursuant to Section
3.24(d), at any time.

     (d) Either party may terminate its participation in the Commercialization
of a Shared Product in any country in the Territory at any time following six
(6) months' prior written notice to the other party. In such case, the other
party may continue Commercialization of such Shared Product as an Independent
Product, either alone or with a third party, and shall thereafter be deemed to
be an Independent Party for such Independent Product solely with respect to such
country or countries, effective as of the

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

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date of the terminating party's notice hereunder, in which case the terminating
party's license under Section 4.1 shall be terminated in the country or
countries in which such party has terminated its participation in the
Commercialization of such Shared Product (the TERMINATED COUNTRIES). In the
event a party elects to cease participating in the Commercialization of a Shared
Product in a country in the Territory and the other party proceeds to
Commercialize such Shared Product in the Terminated Countries as an Independent
Product, the terminating party shall (i) transfer and assign to the Independent
Party all regulatory submissions and Regulatory Approvals in such country
relating to such former Shared Product, together with all materials and data
related thereto in its possession, and (ii) transfer to the Independent Party
all other relevant information that will enable such Independent Party to
Commercialize such former Shared Product as an Independent Product in such
country. A non-Independent Party may not reinitiate its participation in the
Commercialization of a Shared Product in any country in the Territory in which
it relinquished such right hereunder. Any relinquishment of a party's right to
Commercialize Shared Products pursuant to this Section 3.23(d) shall not be a
breach of this Agreement. If both parties terminate their participation in the
Commercialization of a Shared Product, the parties will confer and mutually
agree on a plan for seeking a third party to conduct such Commercialization.

     (e) The parties shall disseminate in the Territory only those promotional
and advertising materials that have been provided or approved for use by the
Steering Committee, and the cost of producing such materials shall be an Expense
of the party incurring such cost. All such materials shall be consistent with
the relevant Marketing Plan and Marketing Budget approved, unanimously, by the
Steering Committee and neither party shall make any claims or representations in
respect of the Shared Products outside the scope of those previously approved by
the Steering Committee.

     (f) The Steering Committee shall designate a party as being primarily
responsible for each country in the Territory for booking sales, establishing
pricing for Shared Products based upon the market analyses performed by the
parties under the direction of the Steering Committee, obtaining necessary
pricing approvals, handling returns and customer complaints and providing
samples. In addition, the Steering Committee shall determine the policies and
procedures necessary to implement the foregoing, including coordination of the
parties' efforts to train sales and marketing representatives for Shared
Products.

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3.25 TRADEMARKS. (a) The parties shall mutually select the trademark or
trademarks for a Shared Product. To the extent commercially reasonable and
appropriate, a single trademark shall be used for each Shared Product in all
countries in the Territory. To the extent the parties determine that the use of
a single trademark for a given Shared Product is impractical or not advisable
given cultural and other differences among countries in the Territory, the
parties shall agree on the appropriate trademark for a Shared Product for use
within different countries within the Territory; PROVIDED that in no event shall
different trademarks be used for the same Shared Product within the same country
in the Territory (unless such Shared Product is being sold for more than one
indication and the parties mutually agree). Each trademark shall be used only in
connection with the applicable Shared Product and shall not be used by either
party on, or in connection with, any other product. The Steering Committee shall
determine which party shall own each trademark used to promote Shared Products
in the Territory and assign responsibility to one or both parties for searching
candidate trademark names and filing, prosecuting, maintaining and all
reasonable steps necessary in defending each Shared Product trademark
application(s) and/or trademark(s), as applicable.

     (b) The party owning a given trademark and related intellectual property
rights in a country in the Territory shall, and hereby does, grant to the other
party a nonexclusive, royalty-free license, with the right to grant sublicenses
only with the prior written consent of the granting party, not to be
unreasonably withheld, to use such trademark to promote and Commercialize Shared
Products as permitted under this Agreement, provided that the party receiving
such license shall refrain from taking any actions that may dilute or otherwise
reduce the value of such trademark. If necessary under the trademark laws of a
country in the Territory, the party owning a given trademark shall record the
other party as an authorized user of such trademark in such country. The parties
shall approve all trade dress, logos, slogans, designs and copyrights used on
and in connection with any Shared Product in the Territory. During the term of
this Agreement, the Screening Committee shall approve all printed materials
bearing each trademark for a Shared Product in the Territory, including but not
limited to business materials, printed materials, advertising materials,
promotional materials and any such other materials that may reference or
incorporate such trademark.

     (c) In the event that any action or proceeding is brought against either or
both NeoGenesis or Immusol with respect to a Shared Product trademark in the
Territory or relating to any alleged infringement of a third

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party's trademark, trade dress or similar intellectual property rights in the
Territory arising out of the parties' promotion or Commercialization of Shared
Products pursuant to this Agreement, each party shall promptly notify the other
and cooperate in the defense of any such action or proceeding, as applicable.
The parties shall agree on the management of such action. In the event Immusol
or NeoGenesis becomes aware of any actual or threatened violation of any
trademark for a Shared Product in any country in the Territory, that party shall
promptly notify the other party and the Steering Committee shall promptly
discuss how to proceed in connection with such actual or threatened violation.
Any expenses incurred by either or both parties for searching candidate
trademark names, filing, prosecuting, maintaining, defending and enforcing
trademark application(s) and/or trademark(s) (as applicable) for Shared Products
shall be included as an element of the Other Allowable Expenses.

3.26 SUPPLY OF SHARED PRODUCT. The Steering Committee shall be responsible for
determining the sources of, and arrangements for, the clinical and commercial
Manufacture and supply of Designated Shared Compounds and Shared Products in a
manner designed to result in long-term profit maximization for such Shared
Products. The Steering Committee shall endeavor to establish multiple sources of
bulk material and fill and finish services and to establish policies for the
maintenance of inventories of key intermediates, bulk material and finished
products and for such other matters as necessary or useful to assure such supply
of Shared Products in the Territory. The Independent Party shall arrange for the
Manufacture and supply of Independent Compounds, Derivative Compounds thereof
and Independent Products, in both bulk and finished form.

3.27 SPECIFICATIONS FOR SHARED PRODUCTS. The parties shall designate one of the
parties to be responsible for establishing, subject to unanimous approval by the
Steering Committee, the specifications for bulk and finished Shared Product, and
providing and maintaining any necessary documentation, certificates of analysis
and test results, for each Shared Product. Copies of all such specifications and
other information and documentation will be provided promptly to each party. In
addition, notice of, and results and data from, all FDA (or its foreign
equivalent) audits relating to the Manufacture of Shared Products will be
provided to each party.

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3.28 TERMS OF MANUFACTURE AND SUPPLY. The parties shall establish procedures
acceptable to both parties regarding forecasting of and ordering for each
party's requirements of the Shared Products in the Territory.

3.29 ADVERSE EVENTS. During the term of this Agreement, each party shall
promptly advise the other by telephone, telefax or overnight delivery service of
every serious or unexpected side effect, adverse reaction or injury that has
been brought to that party's attention and which is alleged to have been caused
by a Shared Product. For each country in the Territory, the party that has the
responsibility for filing the Regulatory Approval and the IND (or foreign
equivalent) in such country for such Shared Product shall have all rights and
responsibilities to report such side effect, adverse reaction or injury to the
appropriate Regulatory Authority(ies) as required by Applicable Laws. The
parties shall establish a procedure for such reporting obligations prior to
commencement of Phase I Clinical Trials for the first Shared Product.

3.30 COMMUNICATION WITH REGULATORY AGENCIES. If a party is contacted by the FDA
or any equivalent regulatory agency in any country in the Territory during the
term of this Agreement pertaining to a Shared Product, Immusol and NeoGenesis
shall promptly, but always within two (2) business days, notify and consult with
one another. The party that has responsibility for regulatory filings for a
Shared Product shall provide an appropriate response to such contact after such
consultation with the other party, except where an earlier response may be
required by law or to assure patient safety.

3.31 SHARED PRODUCT RECALL. In the event that NeoGenesis or Immusol determines
that an event, incident or circumstance has occurred that may result in the need
for a recall or other removal of any Shared Product or any lot or lots thereof
from the market in a country within the Territory, it shall promptly advise and
consult with the other party with respect thereto. Thereafter, on a
country-by-country basis, the owner of the Regulatory Approval for such Shared
Product in a country shall, in its sole discretion (except as otherwise required
by such government authority), have the right to order a recall or other removal
after such consultation, and the other party shall co-operate with such recall.
Any expenses related to a recall in the Territory for a Shared Product shall be
included in Recall Expenses.

4.   LICENSE; PROPRIETARY RIGHTS

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4.1  GRANT OF LICENSE. (a) Subject to the terms and conditions of this
Agreement, NeoGenesis hereby grants to Immusol, and Immusol hereby accepts, a
co-exclusive (with NeoGenesis) worldwide right and license, without the right to
sublicense except in accordance with Section 4.1(c), within the Territory, to
use (i) the NeoGenesis Intellectual Property and NeoGenesis Patent Rights and
(ii) the Program Intellectual Property owned by NeoGenesis, in each case with
application to the Field to the extent necessary or useful to research, develop,
have developed, make, have made, use, distribute, promote, market, offer for
sale, sell, have sold, import and export Designated Shared Compounds, Derivative
Compounds thereof, Shared Products and, to the extent permitted under Section
3.15, Independent Compounds, Derivative Compounds thereof and Independent
Products.

     (b) Subject to the terms and conditions of this Agreement, Immusol hereby
grants to NeoGenesis, and NeoGenesis hereby accepts, a co-exclusive (with
Immusol), worldwide right and license, without the right to sublicense except in
accordance with Section 4.1(c), within the Territory, to use (i) the Immusol
Intellectual Property and Immusol Patent Rights and (ii) the Program
Intellectual Property owned by Immusol, in each case with application to the
Field to the extent necessary or useful to research, develop, have developed,
make, have made, use, distribute, promote, market, offer for sale, sell, have
sold, import and export Designated Shared Compounds, Derivative Compounds
thereof and Shared Products and, to the extent permitted under Section 3.15,
Independent Compounds, Derivative Compounds thereof and Independent Products.

     (c) Either party may sublicense the rights licensed under this Section 4.1
with the prior written consent of the other party (such consent not to be
unreasonably withheld) to a licensee that: (i) agrees in writing to accept all
terms and conditions of this Agreement; and (ii) accepts all other reasonable
conditions of the non-licensing party.

     (d) The licenses granted under this Section 4.1 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 the
party holding the license from the other party 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.

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     (e) Each party, as applicable, shall mark or have marked all containers or
packages of Shared Products or Independent Products that are the subject of the
license granted under this Section 4.1 in accordance with the patent marking
laws of the jurisdiction in which such products are manufactured, used or sold.

     (f) Subject to the next succeeding sentence and the provisions of
Section 8.4, unless sooner terminated in accordance with Section 8.2, the
licenses under Sections 4.1 (a) and 4.1 (b) with respect to Designated Shared
Compounds, Derivative Compounds thereof, Shared Products, Independent Compounds,
Derivative Compounds thereof and Independent Products will remain in effect on a
compound-by-compound, product-by-product and country-by-country basis until the
earlier to occur of the first date on which: (i) Net Sales on Shared Products
and Independent Products, as the case may be, shall be reduced from a positive
number to zero; and (ii) neither party is then pursuing research, Pre-Clinical
Development or Development of the applicable Designated Shared Compound,
Derivative Compound thereof, Shared Product, Independent Compound, Derivative
Compound thereof or Independent Product, in each case using Commercially
Reasonable Efforts. If either party elects to terminate participation in the
Pre-Clinical Development or Development of any Designated Shared Compounds,
Derivative Compound thereof or Shared Product in accordance with Section 3.14,
any license granted to the non-participating party with respect to the
applicable Designated Shared Compound, Derivative Compound thereof or Shared
Product shall terminate until such time (if any) as a party resumes
participation in the Pre-Clinical Development or Development of such Designated
Shared Compound, Derivative Compound thereof or Shared Product, in which case
such license shall revive and be of full force and effect with respect to such
Designated Shared Compound, Derivative Compound thereof or Shared Product until
terminated in accordance with the first sentence of this Section 4.1(e).

4.2  PROPRIETARY RIGHTS. (a) This Agreement does not convey to NeoGenesis any
rights in any Inunusol Intellectual Property, Immusol Patent Rights or any other
intellectual property, patents or patent applications of Immusol by implication,
estoppel or otherwise except for the rights expressly granted in Sections 2.3
and 4.1. Title to the Immusol Intellectual Property, Immusol Patent Rights and
any other intellectual property, patents or patent applications of Immusol shall
at all times remain vested in Immusol.

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     (b) This Agreement does not convey to Immusol any rights in any NeoGenesis
Intellectual Property, NeoGenesis Patent Rights or any other intellectual
property, patents or patent applications of NeoGenesis by implication, estoppel
or otherwise except for the rights expressly granted in Sections 2.3 and 4.1.
Title to the NeoGenesis Intellectual Property, NeoGenesis Patent Rights and any
other intellectual property, patents or patent applications of NeoGenesis shall
at all times remain vested in NeoGenesis.

     (c) 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. Except
as described in the last sentence of this Section 4.2(b), 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 Immusol 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 Immusol. 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 4.2(a)(ii)(B) below),
ALIS or QSCD; and (ii) the property of Immusol if such Program Intellectual
Property is directly related to the Targets or the uses thereof or to Immusol's
functional or secondary assays.

     (d) If required, patent counsel mutually acceptable to the parties and
selected by the Steering Committee shall determine inventorship of all Program
Intellectual Property in accordance with U.S. patent law (and other U.S.
intellectual property law, if applicable).

     (e) NeoGenesis shall retain the following rights with respect to the
following NeoGenesis Intellectual Property and Program Intellectual Property
owned by NeoGenesis: (i) subject to Sections 2.6(a), 4.1(a), 4.2(a), 4.2(e) and
5.2, NeoGenesis may continue to use its NeoMorph Screening Library to screen
target proteins for other parties; and (ii) NeoGenesis shall retain all rights
and may continue to use Preliminary Compounds created as part of the Screening
Program but not selected as Primary Active Compounds and Primary Active
Compounds not selected as Selected Compounds; PROVIDED, HOWEVER, that such
Preliminary Compounds and Primary Active Compounds (A) may not be used against
the Shared Targets

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and (B) shall only be used in the event and to the extent they result from use
of the NeoMorph Screening Library to screen target proteins for other parties
and (C) NeoGenesis will remove all Selected Shared Compounds from the NeoMorph
Screening Library.

     (f) Neither party shall use Program Intellectual Property owned by the
other party or Confidential Information of the other party outside of the
performance of the Program or except as otherwise expressly permitted in this
Agreement.

4.3  DISCLOSURE; PATENT PROSECUTION. (a) Each of NeoGenesis and Immusol shall
promptly disclose to the other in writing any Invention that might, under the
applicable U.S. patent laws, be patentable and constitutes Program Intellectual
Property. Such Program Intellectual Property will be added to ATTACHMENT B.
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 and mutually agree as to appropriate protection for such
Program Intellectual Property, including a patent application, preparation,
prosecution and maintenance strategy. Notwithstanding the provisions of this
Section 4.3, neither party shall file any Program Patent Right relating to
Program Intellectual Property that is jointly owned without the other party's
prior written consent.

     (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 Immusol copies of all patents, patent applications,
substantive patent office actions, and substantive responses received or filed
in connection with such applications (other than patents and patent applications
covering solely NeoGenesis Intellectual Property that is not licensed to Immusol
under Section 4.1 or assigned to Immusol pursuant to Section 4.2(b)). In the
case of patent applications and responses, copies will be furnished to Immusol
at least fifteen (15) days before filing or mailing, as the case may be. Immusol
may itself or through its attorney offer comments and suggestions with respect
to the matters that are the subject of this Section 4.3(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. Immusol
shall cooperate in the preparation, filing, prosecution and maintenance of any
and all patent applications and patents covering Program Intellectual Property
owned by NeoGenesis or obtained by

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NeoGenesis pursuant to the last sentence of Section 4.2(b. NeoGenesis shall
promptly provide notice to Immusol as to all matters that come to its attention
that may affect the preparation, filing, prosecution or maintenance of any
patents or patent applications covering Program Intellectual Property owned by
NeoGenesis. NeoGenesis shall not seek patent protection for any NeoGenesis
Intellectual Property or Program Intellectual Property owned by NeoGenesis
covering any Designated Shared Compounds and Derivative Compounds (including any
generic composition of matter claims with respect thereto and any Selected
Shared Compounds contained therein) until the date specified in Section 3.2 for
each party's election of Designated Shared 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 Immusol of such decision at
least forty five (45) days prior to the due date of any action or payment due.
Immusol shall then have the right, but not the obligation, to assume the
responsibility therefor at its own cost and expense.

     (c) Immusol shall have the sole right, but not the obligation, to prepare,
file, prosecute, and maintain, at Immusol's sole expense, each of the Immusol
Patent Rights throughout the Territory. Immusol shall promptly furnish or have
furnished to NeoGenesis copies of all patents, patent applications, substantive
patent office actions and substantive responses received or filed in connection
with such applications (other than patents and patent applications covering
solely Immusol Intellectual Property that is not licensed to NeoGenesis under
Section 4.1 or assigned to NeoGenesis pursuant to Section 4.2(b)). In the case
of such patent applications and responses, copies will be furnished to
NeoGenesis at least fifteen (15) days before filing or mailing, as the case may
be. NeoGenesis may itself or through its attorney offer comments and suggestions
with respect to the matters that are the subject of this Section 4.3(c) and
Immusol agrees to consider such comments and suggestions; PROVIDED that nothing
herein shall obligate Immusol to adopt or follow such comments or suggestions.
NeoGenesis shall cooperate in the preparation, filing, prosecution and
maintenance of any and all patent applications and patents covering Program
Intellectual Property owned by Immusol or obtained by Immusol pursuant to the
last sentence of Section 4.2(b). Immusol 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 covering Program Intellectual Property owned by Immusol relating to
Generic

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Rights. Immusol shall not file any patent application covering any Designated
Shared Compounds and Derivative Compounds (including any generic composition of
matter claims with respect thereto and any Selected Shared Compounds contained
therein) without NeoGenesis' prior written consent before the date specified in
Section 3.2 for each party's election of Designated Shared Compounds.

4.4  ENFORCEMENT. (a) NeoGenesis shall be solely responsible for defense and
enforcement of (i) NeoGenesis Intellectual Property and NeoGenesis Patent Rights
and (ii) Program Intellectual Property solely owned by NeoGenesis. Immusol shall
be solely responsible for the defense and enforcement of (A) Immusol
Intellectual Property and Immusol Patent Rights and (B) Program Intellectual
Property solely owned by Immusol.

     (b) The parties shall confer and mutually agree upon the manner in which
they will pursue any enforcement or defense of Program Intellectual Property
that is jointly owned; PROVIDED, that (i) the parties shall contribute equally
to any such enforcement or defense action (and to any settlement or judgment
paid in respect of such action); (ii) neither party shall settle such action
without the consent of the other, which consent shall not be unreasonably
withheld; and (iii) the parties shall each be reasonably informed of the
progress of any such enforcement or defense and shall each be provided with
copies of any documents related to such proceedings and reasonable notice of all
proceedings relating to same.

     (c) Any recovery of damages in any defense or enforcement matter relating
to Designated Shared Compounds, Derivative Compounds thereof, Shared Products,
Independent Compounds, Derivative Compounds thereof and Independent Products
(obtained by settlement or otherwise) shall be applied first in satisfaction of
any unreimbursed expenses and legal fees of the party(ies) handling the suit or
settlement thereof. The balance of any such recovery shall be divided equally
between the parties. No settlement, consent judgment or other voluntary final
disposition of any suit regarding Designated Shared Compounds, Derivative
Compounds thereof, Shared Products, Independent Compounds, Derivative Compounds
thereof and Independent Products may be entered into without the consent of the
other party, which consent shall not be unreasonably withheld.

     (d) Notwithstanding the provisions of Section 4.4(b), in the event that a
declaratory judgment action alleging invalidity or non-infringement of any of
the patents within NeoGenesis Patent Rights covering the NeoMorph Screening
Library, ALIS or QSCD is filed, NeoGenesis shall

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have the first option, within sixty (60) days after notification of same, to
assume defense of the action concerning such patents at its expense, but Immusol
shall be entitled to participate in such action, at its own expense.

     (e) In any infringement suit as either party may institute to enforce
Immusol Intellectual Property, Immusol Patent Rights, NeoGenesis Intellectual
Property, NeoGenesis Patent Rights or Program Intellectual Property, or in any
declaratory judgment action alleging invalidity or non-infringement of any
Immusol Intellectual Property, Immusol Patent Rights, NeoGenesis Intellectual
Property, NeoGenesis Patent Rights or Program Intellectual Property brought
against NeoGenesis or Immusol, 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.

     (f) Notwithstanding any provisions of Section 4.4 to the contrary, each
party shall promptly give written notice to the other of any certification of
which it becomes aware filed pursuant to the Hatch-Waxman Act (21 U.S.C.
Section 355(b)(2)(A), or Section 355(j)(2)(A)(vii)), or any amendment or
successor statute thereto, at least fourteen (14) days prior to expiration of
the forty five (45) day period set forth in 21 U.S.C. Section 355(c)(3)(c)
(or any amendment or successor statute thereto), and the parties shall each
perform their obligations under Section 4.4(a) or 4.4(b), as applicable, so
that they are able to commence an infringement action in respect of such
matter within the applicable statutory period.

5.   CONFIDENTIALITY
5.1  PUBLICITY. The parties shall 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. Thereafter, unless
permitted by the preceding sentence, each party agrees not to issue any press
release or other public statement, written or oral, to the public, the press,
the stockholders or otherwise, relating to this Agreement that has not
previously been approved in writing 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

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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) Except as permitted in accordance with Section 5.1,
either party may only disclose the general nature, but not the specific
financial or other material 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 enforce its rights under this
Agreement in a proceeding in accordance with Section 9.1, (iii) to any legal or
financial advisor of such party, or (iv) in response to a subpoena or other
validly issued administrative 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 (to the extent possible)
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) Confidential Information of each party and Program Intellectual
Property owned by such party will be used by the other party solely for the
purposes permitted by this Agreement. All Confidential Information and any
Program Intellectual Property owned by a party will be received and held in
confidence by the receiving party, subject to the provisions of this Agreement.
Each party acknowledges that, except for the rights expressly granted under this
Agreement, 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).

     (c) Each party will restrict disclosure of the other party's Confidential
Information and any Program Intellectual Property owned by such party to those
of its employees and consultants to whom it is necessary or useful to disclose
such Confidential Information and Program Intellectual Property in connection
with the purposes permitted under this Agreement. Each party shall use
reasonable efforts, including at least efforts fully commensurate with those
employed by the party for the protection of its

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own Confidential Information, to protect the Confidential Information and
Program Intellectual Property of the other party.

     (d) 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 and any Program Intellectual Property owned by such
party. 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 any Program
Intellectual Property owned by such party; 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; provided, however, that a party is permitted to retain one copy of such
materials in its legal files to be used to verify compliance with its
obligations hereunder.

     (e) Nothing herein shall prevent a receiving party from disclosing all or
part of the Confidential Information and any Program Intellectual Property owned
by the disclosing party in response to a subpoena or other validly issued
administrative 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 (to the extent possible) and
permits the disclosing party to oppose or narrow such request for disclosure and
supports any of the disclosing party's reasonable efforts to oppose such request
(at disclosing party's expense) and shall disclose such Confidential Information
or Program Intellectual Property only in the event of a final judgement or
administrative order requiring such disclosure, and only to the extent necessary
to comply with such request.

5.3  PUBLICATIONS. Each party recognizes that the publication of papers
regarding results of the Screening 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 Screening Program
hereunder, including oral presentations and

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abstracts, which utilizes data generated from the Screening Program and/or
includes Confidential Information 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 Immusol and NeoGenesis represent and
warrant to the other that: (a) it is a corporation 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
under any other agreement; (c) it has duly executed and delivered this
Agreement; and (d) it is authorized to disclose any and all Confidential
Information made available to the other party pursuant to this Agreement.

6.2  PERFORMANCE. (a) NeoGenesis hereby represents and warrants to Immusol that:
(i) NeoGenesis shall perform the Screening 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 Immusol the licenses in Sections 2.3
and 4.1.

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     (b) NeoGenesis hereby represents and warrants to Immusol 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 Screening Program.

     (c) Immusol hereby represents and warrants to NeoGenesis that, as of the
Effective Date, there is no agreement known to Immusol to which it is a party
and by which it is bound that would conflict with or be breached by Immusol
granting NeoGenesis the licenses in Sections 2.3 and 4.1.

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 ANY MATTER WHATSOEVER, INCLUDING BUT NOT
LIMITED TO, THE NEOMORPH SCREENING LIBRARY, THE NEOMORPH FOCUSED LIBRARIES,
QSCD, THE PRELIMINARY COMPOUNDS, THE PRIMARY ACTIVE COMPOUNDS, THE SELECTED
SHARED COMPOUNDS, THE DESIGNATED SHARED COMPOUNDS, THE SHARED TARGETS, THE
SHARED PRODUCTS, THE NEOGENESIS INTELLECTUAL PROPERTY, THE IMMUSOL INTELLECTUAL
PROPERTY, THE SCOPE, VALIDITY OR ENFORCEABILITY OF THE NEOGENESIS PATENT RIGHTS,
THE IMMUSOL PATENT RIGHTS OR PROGRAM PATENT RIGHTS, OR SUCH PARTY'S OBLIGATIONS
UNDER THIS AGREEMENT.

     (b) THE REPRESENTATIONS AND WARRANTIES OF EACH OF NEOGENESIS AND IMMUSOL
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 7.2-7.4.

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,

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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 (EXCLUDING INFRINGEMENT). Subject to the provisions of
Section 7.4, each of NeoGenesis and Immusol (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(ies) by any third
party arising from or related to: (i) any material breach of the Indemnifying
Party's representations and warranties under this Agreement; or (ii) 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; or (iii) the
labeling, packaging, package insert, other materials or promotional claims with
respect to any Shared Product or Independent Product or the Development,
testing, Manufacturing, Commercialization, use or other disposition of any
Shared Product or Independent Product by the Indemnifying Party or by an
Affiliate, licensee, sublicensee, distributor or agent of the Indemnifying
Party; or (iv) (with respect to Immusol 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 Immusol or by an Affiliate, licensee,
sublicensee, distributor or agent of Immusol. 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 Immusol 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 Immusol in
accordance with the terms of this

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Agreement violates or infringes the intellectual property rights of any third
party. NeoGenesis shall have no liability or obligation to Immusol 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 Immusol or its
Affiliates, or its or their respective employees, officers, directors or agents.

     (b) Subject to the provisions of Section 7.4, Immusol 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 Immusol Intellectual Property or
practice of the Immusol Patent Rights by NeoGenesis in accordance with the terms
of this Agreement violates or infringes the intellectual property rights of any
third party. Immusol 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 to the Indemnifying
Party (and its insurer), as reasonably requested, at Indemnifying Party's cost
and 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.

8.   TERM AND TERMINATION
8.1  TERM. This Agreement shall take effect as of the Effective Date and shall
remain in effect until the expiration of the last to expire of the licenses
granted hereunder, unless sooner terminated in accordance with Section 8.2. The
Screening Program will have a duration of three (3) years

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from the Effective Date. If the parties designate Designated Shared Compounds,
the license(s) thereto will be exercised with respect to such Designated Shared
Compounds and will remain in effect until (i) the expiration of the term of the
last-to-expire of the patent rights within NeoGenesis Patent Rights or Program
Intellectual Property or (ii) ten (10) years following the First Commercial Sale
of Shared Products or Independent Products (if the Shared Products or
Independent Products, as applicable, do not embody any patents within NeoGenesis
Intellectual Property or Program Intellectual Property owned by NeoGenesis),
whichever is later.

8.2  TERMINATION. (a) Either party may terminate the license under Section 4.1
with sixty (60) days' notice if the other party commits a material breach
(including non-payment), unless the breach is cured within the sixty (60)-day
notice period; PROVIDED that if more than one compound is being developed or
commercialized by a party or its Affiliates hereunder, and the other party
terminates this Agreement pursuant to this Section 8.2(b) due to a breach
relating only to a single compound, then the terminating party shall be entitled
to terminate this Agreement only with respect to the applicable compound.

     (c) The parties may terminate this Agreement, or the license under
Section 4.1 on a compound-by-compound, product-by-product or country-by-country
basis, at any time upon mutual written agreement of the parties.

     (d) If voluntary or involuntary proceedings by or against a party are
instituted in bankruptcy under any insolvency law, or a receiver or custodian is
appointed for such party, or proceedings are instituted by or against such party
for corporate reorganization or the dissolution of such party, which
proceedings, if involuntary, shall not have been dismissed within sixty (60)
days after the date of filing, or if such party makes an assignment for the
benefit of creditors, or substantially all of the assets of such party are
seized or attached and not released within sixty (60) days thereafter, the other
party may immediately terminate this Agreement effective upon notice of such
termination.

8.3  EFFECT OF TERMINATION. (a) Upon termination (including expiration) of this
Agreement: (i) the parties will terminate all tasks then in process in an
orderly manner, as soon as practical and in accordance with a schedule agreed to
by Immusol and NeoGenesis; (ii) if termination occurs prior to completion of the
Screening Program then NeoGenesis shall deliver to

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Immusol all materials developed through the termination of this Agreement; (iii)
each party shall pay to the other party any uncontested monies due and owing up
to the time of termination; and (iv) within thirty (30) days following
termination (including expiration) of this Agreement, NeoGenesis shall deliver
to Immusol a reasonably-detailed written report describing the results of the
research performed under the Screening Program 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 or Program Intellectual Property owned by the other
party; provided, however, that a party is permitted to retain one copy of such
materials in its legal files to be used to verify compliance with its
obligations hereunder.

     (c) The license granted by NeoGenesis under Section 4.1 (a) shall survive
any expiration or termination of the Screening Program or this Agreement with
respect to any Designated Shared Compound, Derivative Compound thereof, Product
and Shared Product for which the applicable fees and milestone fees and
royalties or the amounts due under Section 3, as applicable, have been paid and
with respect to any Independent Compound, Derivative Compound thereof and
Independent Product for which the amounts due under Section 3 have been paid (in
each case in accordance with the terms of this Agreement); PROVIDED that Immusol
continues to pay NeoGenesis the fees and royalties as required by Sections 4.3,
4.4 and 4.5 and complies with Sections 4.6-4.9, or to pay NeoGenesis the amounts
due under Section 3, as applicable. The license granted by Immusol under
Section 4.1 (b) shall survive any expiration or termination of this Agreement
with respect to any Designated Shared Compound, Derivative Compound thereof,
Shared Product, Independent Compound, Derivative Compound thereof and
Independent Product for which the amounts due under Section 3 have been paid (in
accordance with the terms of this Agreement). The license granted under Section
4.1 shall not survive termination or expiration of the Screening Program or this
Agreement with respect to Designated Shared Compounds, Derivative Compounds
thereof, Shared Products, Independent Compounds, Derivative Compounds thereof
and Independent Products for which the applicable fees and milestone fees and
royalties or the amounts due under Section 3, as applicable, have not been paid
in accordance with this Agreement. In the event the license granted to Immusol
under Section 4.1 terminates for any reason, each of Immusol's sublicensees at
such time

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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. Either
party's liability for any uncontested charges, payments or expenses due to the
other party 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.

8.4  SURVIVAL. Sections 1, 2.3(b) (last sentence), 2.4(a), 2.6, 3.3 (last
sentence), 3.4 (last sentence), 3.22 and 5-9 shall survive any termination or
expiration of this Agreement. In addition, the licenses granted under Section
4.1 shall survive to the extent necessary to permit a party opting to proceed
with Pre-Clinical Development, Development, Manufacture and Commercialization of
a Discontinued Compound or Non-Proposed Compound as contemplated in the last
sentence of Sections 3.3 and 3.4, respectively; PROVIDED, that such party
complies with the provisions of Section 3.15(c) and the provisions of this
Agreement referenced therein, which provisions shall survive termination or
expiration for this purpose.

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). Representatives of the parties
shall meet within thirty (30) days after the date that the non-sending party
receives the Dispute Notice to attempt in good faith to reach an agreement about
the nature of the dispute and a resolution of the dispute. 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.

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9.2  GOVERNING LAW. This Agreement shall be governed and construed in accordance
with the internal, substantive laws of the State of Delaware 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, as
applicable, for purposes of governing and construing Sections 4.2-4.4 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 parry 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 Immusol 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. Each party shall be solely responsible for compensating all its
personnel and for payment of all related FICA, workers' compensation,
unemployment and withholding taxes. Neither party shall provide the other
party's 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; or (c) a single Person of which such
party owns a majority of the voting stock; PROVIDED, FURTHER, that in each
instance the assignee expressly

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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.

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 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

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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.

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 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.

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 DRUG                                             IMMUSOL INCORPORATED
DISCOVERY, INC.

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BY  /S/ ROBERT ADELMAN                       BY  /S/ TSVI GOLDENBERG
------------------------------------         -----------------------------------
Robert Adelman                               Tsvi Goldenberg, Ph.D.
Vice President, Business Development         Chairman and CEO
NOTICE ADDRESS:                              NOTICE ADDRESS:
NeoGenesis Drug Discovery, Inc.              Immusol Incorporated
840 Memorial Drive                           10790 Roselle Street
Cambridge, MA  02139                         San Diego, CA 92121
Phone: 617.868.1500                          Phone: 858.824.1100
Fax: 617.868.1515                            Fax: 858.824.1112






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                                  ATTACHMENT A

                                SCREENING PROGRAM

NeoGenesis will screen [*] compounds contained in the NeoGenesis NeoMorph
Screening Library against each Shared Target using the protocol described below.

1.   Immusol will provide NeoGenesis with [*] of each of the purified
functionally-active Shared Target proteins and may, at Immusol's option, provide
additional quantities if requested by NeoGenesis. NeoGenesis will perform
initial experiments on the Shared 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 [*] compounds
from the NeoMorph Screening Library against each Shared Target. The ALIS
screening will be carried out under moderately stringent conditions to
identify compounds that bind to the Shared Target with binding affinities
better than [*] micromolar (Kd < [*]) (each such compound is a PRELIMINARY
COMPOUND).

3.   If NeoGenesis identifies a Preliminary Compound(s) for the Shared Target
and Immusol is able to provide NeoGenesis with a second protein that differs
from the Shared Target but is of the same functional class of protein as the
Shared Target, NeoGenesis will screen such second protein against the
Preliminary Compound(s) to determine the relative selectivity of the Preliminary
Compound for the Shared Target(s). Alternatively, if Immusol is unable to
deliver a second protein of the same functional class, NeoGenesis will screen an
unrelated protein selected by the Screening Committee against the Preliminary
Compound(s) to assay the specificity of the initial Preliminary Compounds. If
Immusol is able to deliver a second protein of the same functional class, then
Immusol will provide NeoGenesis with [*] of such protein.

4.   If NeoGenesis identifies a Preliminary Compound(s) for the Shared Target,
NeoGenesis will re-synthesize a NeoMorph library containing each such
Preliminary Compound and subject each such Preliminary Compound to ALIS
screening for confirmation of binding to the Shared Target(s).

5.   After performing the selectivity analysis and confirmatory ALIS screening
described in Paragraphs 3 and 4 above on the Preliminary Compound(s), the
Steering Committee will review the structure(s), binding affinities and target
specificities of such Preliminary Compound(s) and choose [*] Preliminary
Compounds as discrete compound(s) (each such compound is referred to as a
DISCRETE COMPOUND) for further testing as described in Paragraphs 6-10 below.

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6.   NeoGenesis will purify all Discrete Compounds and subject them to screening
on an individual basis for confirmation of binding to the Shared Target. In
addition, at Immusol's option, either (i) NeoGenesis will deliver to Immusol [*]
of each Discrete Compound and Immusol will evaluate the activity of these
Discrete Compound(s) in a Shared Target-based functional assay and will notify
NeoGenesis of the results of such assays, including any Discrete Compounds which
have demonstrated activity in the Shared Target-based functional assays (each, a
PRIMARY ACTIVE COMPOUND) within [*] after completion of such assays and not
later than [*] after the Discrete Compounds are delivered by NeoGenesis or, (ii)
NeoGenesis will evaluate the activity of the Discrete Compound(s) in Shared
Target-based functional assay(s) that have been delivered to NeoGenesis by
Immusol and will notify Immusol of any Primary Active Compounds within [*] after
completion of such assays and not later than [*] after the Shared Target-based
functional assay is delivered by Immusol.

7.   If either Immusol or NeoGenesis identifies one or more Primary Active
Compounds pursuant to Paragraph 6, then NeoGenesis will prepare a report for all
Primary Active Compound(s) that details the chemical structures, binding
affinities, Target specificities, functional activities and competition analysis
data for such Primary Active Compound(s) (each, a FINAL SHARED TARGET REPORT).
NeoGenesis will deliver such Final Shared Target Report to Immusol when it
notifies Immusol of such Primary Active Compounds or, if Immusol has conducted
the functional assays, within [*] of receipt of the results of such assays from
Immusol.

8.   The Steering Committee will select [*] Primary Active Compounds per Shared
Target, for further study or optimization (each, a SELECTED SHARED COMPOUND).

9.   NeoGenesis will perform optimization on Selected Shared Compounds as
directed by the Steering Committee. To perform such optimization, NeoGenesis
will create NeoMorph Focused Libraries based upon such Selected Shared Compounds
and will perform high stringency-ALIS screening to improve Kd values to [*]
micromolar or better (i.e., Kd < [*]).

10.  NeoGenesis will provide Immusol with [*] of each discrete Selected Shared
Compound(s) for further evaluation by Immusol in Target-based secondary assays
and, at the option of the Steering Committee, exploratory chemistry or
toxicological studies, on a shared-cost basis in accordance with Section 3.
Immusol will notify NeoGenesis of any such Selected Shared Compound(s) which
demonstrate activity in the Shared Target-based secondary assays within [*]
after completion of such assays and not later than [*] after the discrete
Selected Shared

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SEPARATELY WITH THE COMMISSION.

                                       2
<Page>

Compounds are delivered by NeoGenesis. Any additional quantities of Selected
Shared Compounds will be furnished at the instruction of the Steering Committee.







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

                                       3
<Page>











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




                                  ATTACHMENT C
                                 SHARED TARGETS:



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












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

                                       4