<Page>

                                                                    Exhibit 10.5

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

VER. EQ.5/8/00                                      RESTATEMENT - EXECUTION COPY
                                                            TLO:  KS/LN


                      MASSACHUSETTS INSTITUTE OF TECHNOLOGY

                                       AND

                          MOMENTA PHARMACEUTICALS, INC.

                              AMENDED AND RESTATED
                       EXCLUSIVE PATENT LICENSE AGREEMENT

        M.I.T.'s offer of this agreement is open until November 15, 2002

<Page>

                                TABLE OF CONTENTS

<Table>
<S>                                                                           <C>
R E C I T A L S................................................................1
1. Definitions................................................................3
2. Grant of Rights............................................................10
3. COMPANY Diligence Obligations..............................................12
4. Royalties and Payment Terms................................................14
5. Reports and Records........................................................18
6. Patent Prosecution.........................................................20
7. Infringement...............................................................23
8. Indemnification and Insurance..............................................26
9. Representations or Warranties..............................................27
10. Assignment................................................................28
11. General Compliance with Laws..............................................28
12. Termination...............................................................29
13. Dispute Resolution........................................................30
14. Miscellaneous.............................................................30
APPENDIX A....................................................................33
APPENDIX B....................................................................34
APPENDIX C....................................................................36
APPENDIX D....................................................................39
APPENDIX E....................................................................41
APPENDIX F....................................................................42
APPENDIX G....................................................................43
</Table>

                                       ii
<Page>

VER. EQ.5/8/00

                      MASSACHUSETTS INSTITUTE OF TECHNOLOGY
             AMENDED AND RESTATED EXCLUSIVE PATENT LICENSE AGREEMENT

     This Agreement, effective as of the date set forth above the signatures of
the parties below (the "EFFECTIVE DATE"), is between the Massachusetts Institute
of Technology ("M.I.T."), a Massachusetts corporation, with a principal office
at 77 Massachusetts Avenue, Cambridge, MA 02139-4307 and Momenta
Pharmaceuticals, Inc., formerly Mimeon, Inc. ("COMPANY"), a Delaware
corporation, with a principal place of business at 43 Moulton Street, Cambridge,
MA 02138.

                                 R E C I T A L S

     WHEREAS, M.I.T. and COMPANY are parties to that Exclusive Patent License
Agreement, dated as of December 31, 2001 (the "ORIGINAL EFFECTIVE DATE"), with
respect to certain of the PATENT RIGHTS (the "ORIGINAL AGREEMENT"); and

     WHEREAS, the parties wish to amend and restate the ORIGINAL AGREEMENT, in
accordance with Section 14.4 thereof, to reflect the terms and conditions
herein, the ORIGINAL AGREEMENT is hereby amended and restated in its entirety to
read as follows.

     WHEREAS, M.I.T. is the owner or a joint owner of certain PATENT RIGHTS (as
later defined herein) relating to:

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

<Page>

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO. [**];

     M.I.T. CASE NO[**];

and has the right to grant licenses under its interest in said PATENT RIGHTS,
subject only to a royalty-free, nonexclusive non-transferable license to
practice the PATENT RIGHTS granted to the United States Government for
government purposes;

     WHEREAS, M.I.T. is the sole owner of the PATENT RIGHTS for M.I.T. Case Nos.
[**].

     WHEREAS, M.I.T. and the [**] jointly own the PATENT RIGHTS for M.I.T. Case
[**] and have signed a joint invention agreement that appoints the M.I.T.
Technology Licensing Office as the sole and exclusive agent for licensing such
PATENT RIGHTS;

     WHEREAS, M.I.T. and the [**] jointly own the PATENT RIGHTS for M.I.T. Case
No. [**] and M.I.T. has contacted [**] for its authorization to act as its agent
for the purposes of licensing [**] rights in the intellectual property of M.I.T.
Case No. [**] in return for a share in royalties;

     WHEREAS, [**] and [**], who are inventors of certain of the PATENT RIGHTS
and are current employees of M.I.T., and [**], who is an inventor of certain of
the PATENT RIGHTS and was a former employee of M.I.T., have acquired equity in
COMPANY not resulting from

                                        2
<Page>

this Agreement, the Conflict of Interest Avoidance Statements of the Drs. [**]
are attached as EXHIBITS A-1, A-2 AND A-3, respectively, hereto;

     WHEREAS, [**], who are inventors of certain of the PATENT RIGHTS, have
acquired equity in COMPANY not resulting from this Agreement, the Waivers of
Participation in M.I.T.'s institutional equity share are attached as EXHIBITS
B-1, B-2 AND B-3, respectively, hereto;

     WHEREAS, M.I.T.'s Vice President for Research approved that [**], who are
inventors of certain of the PATENT RIGHTS and are current employees of M.I.T.,
and [**] who is an inventor of certain of the PATENT RIGHTS and was a former
employee of M.I.T., hold equity in COMPANY and that M.I.T. accept and hold
equity as partial consideration for the rights and licenses granted under this
Agreement;

     WHEREAS, M.I.T. desires to have the PATENT RIGHTS developed and
commercialized to benefit the public and is willing to grant a license
thereunder;

     WHEREAS, COMPANY has represented to M.I.T., to induce M.I.T. to enter into
this Agreement, that COMPANY shall commit itself to a thorough, vigorous and
diligent program of exploiting the PATENT RIGHTS so that public utilization
shall result therefrom; and

     WHEREAS, COMPANY desires to obtain a license under the PATENT RIGHTS upon
the terms and conditions hereinafter set forth.

     NOW, THEREFORE, M.I.T. and COMPANY hereby agree as follows:

                                 1. DEFINITIONS.

     1.1 "AFFILIATE" shall mean any legal entity (such as a corporation,
partnership, or limited liability company) that is controlled by COMPANY. For
the purposes of this definition, the term "control" means (i) beneficial
ownership of at least fifty percent (50%) of the voting securities of a
corporation or other business organization with voting securities or (ii) a
fifty percent (50%) or greater interest in the net assets or profits of a
partnership or other business organization without voting securities.

                                        3
<Page>

     1.2 "CORPORATE PARTNER" shall mean:
            a) any entity which agrees to compensate (either in cash or
non-cash) COMPANY for any one or more of the rights to market, distribute, sell,
use, and/or transfer LICENSED PRODUCTS and/or LICENSED PROCESSES; or

            b) any entity which agrees to compensate (either in cash or
non-cash) COMPANY for the right to incorporate LICENSED PRODUCTS in its own drug
delivery system(s) and for any one or more of the rights to market, distribute,
sell, use, and/or transfer the resulting combination; or

            c) any entity which agrees to compensate (either in cash or
non-cash) COMPANY for the right to attach its own biologically active agent(s)
to LICENSED PRODUCTS and for any one or more of the rights to market,
distribute, sell, use, and/or transfer the resulting combination.

     Any CORPORATE PARTNER, as defined in this Section, that also receives a
sublicense of the PATENT RIGHTS shall also be considered a SUBLICENSEE.

     1.3 "CORPORATE PARTNER INCOME" shall mean any payments that COMPANY or an
AFFILIATE receives from a CORPORATE PARTNER in consideration for the rights
described in Section 1.2, including without limitation license fees, MILESTONE
PAYMENTS, license maintenance fees, and other payments, but specifically
excluding royalties on NET SALES. Payments received by COMPANY for the purchase
or sale of equity in COMPANY at a price up to and including the FAIR MARKET
VALUE are excluded from this definition. The amount of such payment which
exceeds the FAIR MARKET VALUE is included in this definition. Bona fide RESEARCH
SUPPORT PAYMENTS are excluded from this definition. Bona fide payments to
COMPANY or AFFILIATES from a CORPORATE PARTNER for rights other than those
described in Section 1.2 are excluded from this definition.

     1.4 "DISCOVERED PRODUCT" shall mean any product identified by the use of
LICENSED PRODUCTS or LICENSED PROCESSES when the product itself or the
manufacture of such product does not infringe PATENT RIGHTS.

     1.5 "DISCOVERED PRODUCT NET SALES" shall mean gross amounts billed by
COMPANY and its AFFILIATES and SUBLICENSEES for DISCOVERED PRODUCTS, calculated
in accordance with Section 1.19, except that (a) the term "DISCOVERED PRODUCTS"
shall be substituted for any references to "LICENSED PRODUCTS" and/or "LICENSED
PROCESSES" and the reference to the exclusion of sales of DISCOVERED PRODUCTS
shall not apply.

                                        4
<Page>

     1.6 "FAIR MARKET VALUE" of a share of Common Stock or other security of the
COMPANY (a "SECURITY") shall be the highest price per share that the COMPANY
could reasonably be expected to obtain from a willing buyer (not a current
employee or director) for shares of such SECURITY sold by the COMPANY, from
authorized but unissued shares, as determined in good faith by the Board of
Directors of the COMPANY, unless the COMPANY shall become subject to a merger,
acquisition or other consolidation pursuant to which the COMPANY is not the
surviving party, in which case the current fair market value of a share of such
SECURITY shall be deemed to be the value received by the holders of the such
SECURITY for each share of such SECURITY pursuant to the COMPANY's acquisition.

     1.7 "FIELD ALL BUT MACHINES" shall mean all fields of use except for the
FIELD SEQUENCING MACHINES.

     1.8 "FIELD HEPARINASE" shall mean all fields of use except for human use of
heparinases as therapeutics in pharmaceutical compositions and except for FIELD
SEQUENCING MACHINES.

     1.9 "FIELD MANUFACTURING" shall mean the use of heparinases in the
commercial manufacture, quality assurance, and/or quality control of commercial
products.

     1.10 "FIELD SEQUENCING MACHINES" shall mean the commercial sale or leasing
of sequencing machines, including the performance of sequencing services, but
only to the extent such sequencing services are (a) required for the seller or
lessor of such a sequencing machine to develop or manufacture such sequencing
machine; or (b) performed by the purchaser of such a sequencing machine using
the sequencing machine. The development, performance and provision of sequencing
services apart from the development, manufacture or use of a commercially sold
sequencing machine are not included within this field.

     1.11 "FIELD THERAPEUTICS" shall mean for
            (a) internal use in the discovery and development of therapeutic
compounds; and

            (b) the clinical testing, manufacture and sale of therapeutic
compounds. This field shall not include the sale of research reagents or of
synthesis machines.

     1.12 "IMPROVEMENT" shall mean any patentable invention, or group of
patentable inventions so linked as to form a single general inventive concept
(as general inventive concept is described in Rule 13 of the Regulations under
the Patent Cooperation Treaty), disclosed to the

                                        5
<Page>

M.I.T. Technology Licensing Office, made under M.I.T. research programs in which
either [**] is the principal investigator, within three (3) years of the
ORIGINAL EFFECTIVE DATE of this Agreement, and which are dominated by the claims
of the PATENT RIGHTS for which exclusive rights are granted in Section 2.2, and
which shall be practiced by COMPANY only in the fields for which exclusive
rights are granted in Section 2.2.

     1.13 "IND" shall mean an investigational new drug application (Form FDA
1571), or any successor form or foreign equivalent.

     1.14 "KNOW-HOW" shall mean M.I.T.-owned technical information, research
results and data that is not protected by patent or by copyright nor intended to
be protected by patent or copyright and is useful for the effective exercise or
use of the PATENT RIGHTS or effective commercialization of LICENSED PRODUCTS or
LICENSED PROCESSES.

     1.15 "LICENSED PROCESS" shall mean any process that, absent the license
granted hereunder, would infringe one or more claims of the PATENT RIGHTS or
which uses a LICENSED PRODUCT.

     1.16  "LICENSED PRODUCT" shall mean any product or part thereof that:
            (a) absent the license granted hereunder, would infringe one or more
claims of the PATENT RIGHTS; or

            (b) is manufactured by using a LICENSED PROCESS or that, when used,
practices a LICENSED PROCESS.

     1.17 "MILESTONE PAYMENTS" shall mean a payment to COMPANY or AFFILIATE from
a CORPORATE PARTNER or SUBLICENSEE due upon achievement of an agreed upon
technical, business, or regulatory milestone pertaining to the research,
development or commercialization of LICENSED PRODUCTS or LICENSED PROCESSES.
Illustrative examples of such milestones include, but are not limited to: using
LICENSED PRODUCTS to deliver a certain drug in a living animal, delivery of a
sample LICENSED PRODUCT customized to the requirements of the CORPORATE PARTNER
or SUBLICENSEE, and obtaining regulatory approval for a LICENSED PRODUCT.
Payments received by COMPANY for the purchase or sale of equity in COMPANY at a
price up to and including the FAIR MARKET VALUE are excluded from this
definition. The amount of such payment which exceeds the FAIR MARKET VALUE is
included in this definition. Bona fide RESEARCH SUPPORT PAYMENTS are excluded
from this definition. Bona fide payments to COMPANY

                                        6
<Page>

or AFFILIATES from a CORPORATE PARTNER or SUBLICENSEE for rights other than
those licensed hereunder are excluded from this definition.

     1.18 "NDA" shall mean a new drug application (Form FDA 356h), or any
successor form or foreign equivalent.

     1.19 "NET SALES" shall mean the gross amount billed by COMPANY and its
AFFILIATES and SUBLICENSEES for LICENSED PRODUCTS and LICENSED PROCESSES, less
the following:
          (i) customary trade, quantity, or cash discounts to the extent
actually allowed and taken;
          (ii) amounts repaid or credited by reason of rejection or return;
          (iii) to the extent separately stated on purchase orders, invoices, or
other documents of sale, any taxes or other governmental charges levied on the
production, sale, transportation, delivery, or use of a LICENSED PRODUCT or
LICENSED PROCESS which is paid by or on behalf of COMPANY; and
          (iv) outbound transportation costs prepaid or allowed and costs of
insurance in transit.

          No deductions shall be made for commissions paid to individuals
whether they be with independent sales agencies or regularly employed by COMPANY
and on its payroll, or for cost of collections. NET SALES shall occur on the
earlier of receipt of payment or ninety (90) days after the date of billing for
a LICENSED PRODUCT or LICENSED PROCESS. If a LICENSED PRODUCT or a LICENSED
PROCESS is distributed at a discounted price that is substantially lower than
the customary price charged by COMPANY, or distributed for non-cash
consideration (whether or not at a discount), NET SALES shall be calculated
based on the non-discounted amount of the LICENSED PRODUCT or LICENSED PROCESS
charged to an independent third party during the same REPORTING PERIOD or, in
the absence of such sales, on the fair market value of the LICENSED PRODUCT or
LICENSED PROCESS. In the event that a LICENSED PROCESS is provided or a LICENSED
PRODUCT is sold in combination with one or more processes or products which are
not LICENSED PROCESSES or LICENSED PRODUCTS, NET SALES shall mean the amount
billed by COMPANY or its AFFILIATES and SUBLICENSEES on sales of the combination
process or product less the deductions set forth above and multiplied by a
proration factor that is determined by the parties in good faith based on the
relative market prices of each component of the combination process. Sales or
other transfers between or among COMPANY and any of its AFFILIATES for the
purpose of subsequent resale to third parties shall not be included in the
calculation of NET SALES. In the event of a sale or

                                        7
<Page>

transfer between the COMPANY and one of its SUBLICENSEES for the purpose of
subsequent resale to third parties, the subsequent resales to third parties
shall not be included in the calculation of NET SALES.

            NET SALES shall not include DISCOVERED PRODUCT NET SALES.

     1.20 "PATENT RIGHTS" shall mean:
            (a)   the United States and international patents listed on
APPENDICES A THROUGH E;
            (b)   the United States and international patent applications and/or
provisional applications listed on Appendices A through E; and the resulting
patents;
            (c)   any patent applications resulting from the provisional
applications listed on APPENDICES A THROUGH E;, and any divisionals,
continuations, continuation-in-part applications, and continued prosecution
applications (and their relevant international equivalents) of the patent
applications listed on APPENDICES A THROUGH E; and of such patent applications
that result from the provisional applications listed on Appendices A through E,
to the extent the claims are directed to subject matter specifically described
in the patent applications listed on APPENDICES A THROUGH E, and the resulting
patents;
            (d)   any patents resulting from reissues, reexaminations, or
extensions (and their relevant international equivalents) of the patents
described in (a), (b), and (c) above; and
            (e)   international (non-United States) patent applications and
provisional applications filed after the ORIGINAL EFFECTIVE DATE and the
relevant international equivalents to divisionals, continuations,
continuation-in-part applications and continued prosecution applications of the
patent applications to the extent the claims are directed to subject matter
specifically described in the patents or patent applications referred to in (a),
(b), (c), and (d) above, and the resulting patents.

     1.21 "PATENT RIGHTS CASE [**]" shall mean the PATENT RIGHTS listed on
APPENDIX A.

     1.22 "PATENT RIGHTS CASE [**] BACKGROUND" shall mean the PATENT RIGHTS
listed on APPENDIX B.

     1.23 "PATENT RIGHTS HEPARIN" shall mean the PATENT RIGHTS listed on
APPENDIX C.

                                        8
<Page>

     1.24 "PATENT RIGHTS HEPARINASE" shall mean the PATENT RIGHTS listed in
APPENDIX D.

     1.25 "PATENT RIGHTS MASSPEC" shall mean the PATENT RIGHTS listed on
APPENDIX E.

     1.26 "REPORTING PERIOD" shall begin on the first day of each calendar
quarter and end on the last day of such calendar quarter.

     1.27 RESEARCH SUPPORT PAYMENTS" shall mean payments to COMPANY or AFFILIATE
from a CORPORATE PARTNER or SUBLICENSEE that are expressly intended only to fund
or pay for equipment, supplies, employees, full time consultants, research,
products, services or expenses incurred or to be incurred on behalf of that
CORPORATE PARTNER or SUBLICENSEE.

     1.28 "SUBLICENSE INCOME" shall mean any payments that COMPANY or an
AFFILIATE receives from a SUBLICENSEE in consideration of a sublicense of the
rights granted COMPANY and AFFILIATES under Section 2.1, including without
limitation license fees, license maintenance fees, and other payments, but
specifically excluding MILESTONE PAYMENTS and royalties on NET SALES. Payments
received by COMPANY for the purchase or sale of equity in COMPANY at a price up
to and including the FAIR MARKET VALUE are excluded from this definition. The
amount of such payment which exceeds the FAIR MARKET VALUE is included in this
definition. Bona fide RESEARCH SUPPORT PAYMENTS are excluded from this
definition. Bona fide payments to COMPANY or AFFILIATES from a SUBLICENSEE for
rights other than those granted under Section 2.1 are excluded from this
definition.

     1.29 "SUBLICENSEE" shall mean any non-AFFILIATE sublicensee of the rights
granted COMPANY under Section 2.1.

     1.30 "TERM" shall mean the term of this Agreement, which shall commence on
the EFFECTIVE DATE and shall remain in effect until the expiration or
abandonment of all issued patents and filed patent applications within the
PATENT RIGHTS, unless earlier terminated in accordance with the provisions of
this Agreement.

     1.31 "UNGRANTED OPTIONS" shall mean the number of securities reserved for
issuance pursuant to any COMPANY stock or stock option plan in effect on the
date of

                                        9
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calculation that is in excess of 15% of the Company's issued and outstanding
shares of Common Stock on the date of calculation.

                               2. GRANT OF RIGHTS.

     2.1 LICENSE GRANTS. Subject to the terms of this Agreement, M.I.T. hereby
grants to COMPANY and its AFFILIATES for the TERM a worldwide, royalty-bearing
license to develop, make, have made, use, sell, offer to sell, lease, and import
LICENSED PRODUCTS and to develop and perform LICENSED PROCESSES (which the
parties acknowledge may result in the identification of DISCOVERED PRODUCTS)
under M.I.T.'s rights in:

            (a)   PATENT RIGHTS HEPARIN and PATENT RIGHTS MASSPEC for FIELD ALL
BUT MACHINES;

            (b)   PATENT RIGHTS CASE [**] for FIELD THERAPEUTICS;

            (c)   PATENT RIGHTS CASE [**] BACKGROUND to enable (and only to
enable) the practice of PATENT RIGHTS CASE [**]; and

            (d)   PATENT RIGHTS HEPARINASE for FIELD HEPARINASE.

     In addition, subject only to the terms of any sponsorship agreement under
which an IMPROVEMENT invention was made, M.I.T. hereby grants to COMPANY a first
option to add IMPROVEMENTS to the PATENT RIGHTS, only in the fields for which
exclusive rights are granted in Section 2.2, for six months after COMPANY has
been notified of the existence of each such IMPROVEMENT. Within one month after
the M.I.T. Technology Licensing Office receives disclosure of any IMPROVEMENT,
and to the extent that the IMPROVEMENT is available for licensing under the
terms of any sponsorship agreement, M.I.T shall notify COMPANY in writing of
such IMPROVEMENT, furnishing COMPANY a copy of the invention disclosure and any
related patent applications. COMPANY may exercise its right to add such
IMPROVEMENT to the PATENT RIGHTS within six months after receipt of M.I.T's
notice by so notifying M.I.T. in writing and paying M.I.T. a fee of [**] Dollars
($[**]) per invention disclosure covering IMPROVEMENTS. Upon COMPANY's exercise
of such right, the Appendix of this Agreement that describes the PATENT RIGHTS
that dominate the IMPROVEMENT shall be deemed to have been amended to add the
invention disclosure (and any related patent applications) covering such
IMPROVEMENT, and such IMPROVEMENT and any resulting patent applications and
patents shall thereafter be included in PATENT RIGHTS for all purposes of this
Agreement, without any additional fee, other than the [**]

                                       10
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Dollar fee referred to in the previous sentence, and M.I.T. shall provide
COMPANY with an updated APPENDIX C OR D for its records.

     2.2 EXCLUSIVITY. In order to establish an exclusive period for COMPANY and
its AFFILIATES, M.I.T. agrees that it shall not grant any other license for
PATENTS RIGHTS HEPARIN in FIELD ALL BUT MACHINES or under the PATENT RIGHTS
HEPARINASE in FIELD MANUFACTURING to develop, make, have made, use, sell, lease
and import LICENSED PRODUCTS or to develop and perform LICENSED PROCESSES during
the TERM.

     2.3 SUBLICENSES.
            (a) COMPANY shall have the right to grant sublicenses of its rights
under Section 2.1, except that COMPANY may only grant sublicenses of PATENT
RIGHTS CASE [**] and PATENT RIGHTS CASE [**] BACKGROUND to third parties in
connection with other licenses from COMPANY to third parties for rights to use
molecules that are (i) discovered, developed and/or tested by COMPANY, and (ii)
the subject of (A) patent rights held by or licensed to COMPANY, or (B) an NDA
filed by COMPANY.

            (b) COMPANY shall incorporate terms and conditions into its
sublicense agreements sufficient to enable COMPANY to comply with this
Agreement. COMPANY shall promptly furnish M.I.T. with a fully signed photocopy
of any sublicense agreement.

            (c) Upon termination of this Agreement for any reason, any
SUBLICENSEE not then in default shall have the right to seek a license from
M.I.T. M.I.T. agrees to negotiate such licenses in good faith under reasonable
terms and conditions.

     2.4 U.S. MANUFACTURING. To the extent required by law, COMPANY agrees that
any LICENSED PRODUCTS used or sold in the United States will be manufactured
substantially in the United States.

     2.5 RETAINED RIGHTS.

            (a)   M.I.T. M.I.T. retains the right to practice under the PATENT
RIGHTS for research, teaching, and educational purposes. In addition, in
accordance with the NIH Guidelines for Patenting of Research Tools, M.I.T.
retains the right to grant to not-for-profit institutions, nonexclusive,
non-transferable licenses under the PATENT RIGHTS HEPARIN for use as research
tools and for research purposes only, specifically not including manufacturing,
quality

                                       11
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assurance, quality control, and clinical testing of commercial products or
characterization of a marketed product for commercial purposes.

            (b)   FEDERAL GOVERNMENT. COMPANY acknowledges that the U.S. federal
government retains a royalty-free, non-exclusive, non-transferable license to
practice any government-funded invention claimed in any PATENT RIGHTS as set
forth in 35 U.S.C. Sections 201-211, and the regulations promulgated thereunder,
as amended, or any successor statutes or regulations.

     2.7 NO ADDITIONAL RIGHTS. Nothing in this Agreement shall be construed to
confer any rights upon COMPANY by implication, estoppel, or otherwise as to any
technology or patent rights of M.I.T. or any other entity other than the PATENT
RIGHTS, regardless of whether such technology or patent rights shall be dominant
or subordinate to any PATENT RIGHTS. Notwithstanding the forgoing, M.I.T.
acknowledges that COMPANY made use of the PATENT RIGHTS and KNOW-HOW for
research purposes before the EFFECTIVE DATE, and M.I.T. agrees that such use was
permitted and that COMPANY shall have no obligations or liabilities to M.I.T.
with respect to such use. In addition COMPANY shall have no obligations or
liabilities to M.I.T. for any future use of any KNOW-HOW that COMPANY has or
will acquire during the TERM.

                        3. COMPANY DILIGENCE OBLIGATIONS.

     3.1 DILIGENCE REQUIREMENTS. COMPANY shall use diligent efforts, or shall
cause its AFFILIATES and SUBLICENSEES to use diligent efforts, to develop
LICENSED PRODUCTS, DISCOVERED PRODUCTS or LICENSED PROCESSES and to introduce
LICENSED PRODUCTS, DISCOVERED PRODUCTS or LICENSED PROCESSES into the commercial
market; thereafter, COMPANY or its AFFILIATES or SUBLICENSEES shall make
LICENSED PRODUCTS, DISCOVERED PRODUCTS or LICENSED PROCESSES reasonably
available to the public. Specifically, COMPANY or AFFILIATE or SUBLICENSEE shall
fulfill the following obligations.

            (a)   Within sixty (60) days after the end of each calendar year,
COMPANY shall furnish M.I.T. with a written report (consistent with Section
5.1(a)) on the progress of its efforts during the immediately preceding calendar
year to develop and commercialize LICENSED PRODUCTS, DISCOVERED PRODUCTS and
LICENSED PROCESSES.

                                       12
<Page>

            (b)   COMPANY shall permit an in-plant inspection by M.I.T. on or
before July 1, 2002 and thereafter permit in-plant inspections by M.I.T. at
regular intervals with at least twelve (12) months between each such inspection.

            (c)   COMPANY shall have raised since inception at least [**]
Dollars ($[**]) by [**] from the sale of COMPANY's equity securities for its own
account.

            (d)   In the aggregate, COMPANY shall have raised since inception at
least [**] dollars ($[**]) by [**] from the sale of COMPANY's equity securities
for its own account and from funding from CORPORATE PARTNERS or SUBLICENSEES.

            (e)   COMPANY shall fund, or shall cause its AFFILIATES to fund no
less than [**] Dollars ($[**]) toward the research, development or
commercialization of LICENSED PRODUCTS, DISCOVERED PRODUCTS and/or LICENSED
PROCESSES in each calendar year (pro-rated for partial years) beginning in the
calendar year [**] and ending with calendar year [**].

            (f)   COMPANY shall fund, or shall cause its AFFILIATES to fund, no
less than [**] Dollars ($[**]) toward the research, development or
commercialization of LICENSED PRODUCTS, DISCOVERED PRODUCTS and/or LICENSED
PROCESSES in each calendar year (pro-rated for partial years) beginning in
calendar year [**] and ending with the first commercial sale of a LICENSED
PRODUCT or first commercial performance of a LICENSED PROCESS.

            (g)   COMPANY shall begin, or shall cause its AFFILIATES, CORPORATE
PARTNERS or SUBLICENSEE to begin, [**] of a LICENSED PRODUCT, DISCOVERED PRODUCT
or LICENSED PROCESS suitable for [**].

            (h)   COMPANY shall file, or shall cause its AFFILIATES, CORPORATE
PARTNERS or SUBLICENSEE to file, [**].

            (i)   COMPANY shall file, or shall cause its AFFILIATES, CORPORATE
PARTNERS or SUBLICENSEE to file, [**].

            (j)   COMPANY shall make, or shall cause its AFFILIATES,
SUBLICENSEES, or CORPORATE PARTNERS to make, [**].

                                       13
<Page>

            (k)   COMPANY shall make NET SALES and DISCOVERED PRODUCT NET SALES
according to the following schedule:

<Table>
                   <S>                                <C>
                  [**]                                $ [**];
                  [**]                                $ [**];
                  [**] and each year thereafter       $ [**].
</Table>

     In the event that M.I.T. determines that COMPANY has failed to fulfill any
of its obligations under this Article 3 and fails to cure such breach within
ninety (90) days after receiving written notice thereof, provided such notice
expressly refers to this Section 3.1 and M.I.T.'s right of conversion, then
M.I.T. may, as its sole remedy, convert the exclusive rights granted in Section
2.2 into non-exclusive rights.

                         4. ROYALTIES AND PAYMENT TERMS.

     4.1 CONSIDERATION FOR GRANT OF RIGHTS.

            (a)   LICENSE ISSUE FEE AND PATENT COST REIMBURSEMENT. M.I.T.
acknowledges that COMPANY paid to M.I.T. on the EFFECTIVE DATE a license issue
fee of [**]Dollars ($[**]), and, in accordance with Section 6.4, has and shall
reimburse M.I.T. for its actual expenses incurred as of the ORIGINAL EFFECTIVE
DATE in connection with obtaining the PATENT RIGHTS. These payments are
nonrefundable.

            (b)   LICENSE MAINTENANCE FEES. COMPANY shall pay to M.I.T. the
following license maintenance fees on the dates set forth below:

<Table>
                  <S>                                         <C>
                  [**] (which payment M.I.T.
                  acknowledges it has received)               $ [**]
                  [**]                                        $ [**]
                  [**]                                        $ [**]
                  [**]                                        $ [**]
                  [**]                                        $ [**]
                  [**]                                        $ [**]
                  [**]                                        $ [**]
                  [**] and
                  [**] every year thereafter                  $ [**]
</Table>

     This annual license maintenance fee is nonrefundable; however, the license
maintenance fee may be credited to running royalties subsequently due on NET
SALES earned during the

                                       14
<Page>

same calendar year, if any. License maintenance fees paid in excess of running
royalties due in such calendar year shall not be creditable to amounts due for
future years.

            (c)   RUNNING ROYALTIES DUE ON NET SALES BY COMPANY AND AFFILIATES.
COMPANY shall pay to M.I.T. a running royalty of:

                  (i)   [**] percent ([**]%) of NET SALES by COMPANY and
     AFFILIATES of LICENSED PRODUCTS or LICENSED PROCESSES which do not fall
     under any of the PATENT RIGHTS for M.I.T. CASES [**];

                                       AND

                  (ii)  [**] percent ([**]%) of NET SALES by COMPANY and
AFFILIATES of LICENSED PRODUCTS or LICENSED PROCESSES which fall under any of
the PATENT RIGHTS for M.I.T. CASES [**];

            (d)   RUNNING ROYALTIES DUE ON NET SALES BY SUBLICENSEES. COMPANY
shall pay to M.I.T. a running royalty of:

                  (i)   If the LICENSED PRODUCT or LICENSED PROCESS does NOT
fall under any of the PATENT RIGHTS for M.I.T. CASES [**], the lesser of:

                        (a) [**] percent ([**]%) of NET SALES by SUBLICENSEES;
        OR

                        (b) [**] percent ([**]%) of the royalty received by
        COMPANY from SUBLICENSEES for NET SALES made by SUBLICENSEES;

                                       AND

              (ii)      If the LICENSED PRODUCT or LICENSED PROCESS falls under
any of the PATENT RIGHTS for M.I.T. CASES [**], the lesser of:

                        (a) [**] percent ([**]%) of NET SALES by SUBLICENSEES;

                                       OR

                        (b) [**] percent ([**]%) of the royalty received by
        COMPANY from SUBLICENSEES for NET SALES made by SUBLICENSEES

     Running royalties shall be payable for each REPORTING PERIOD and shall be
due to M.I.T. within sixty (60) days after the end of each REPORTING PERIOD.

                                       15
<Page>

            (e)   SHARING OF OTHER INCOME. COMPANY shall pay M.I.T. a total of
[**] percent ([**]%) of all SUBLICENSE INCOME and CORPORATE PARTNER INCOME
received by COMPANY or by its AFFILIATES. Such amount shall be payable for each
REPORTING PERIOD and shall be due to M.I.T. within sixty (60) days after the end
of each REPORTING PERIOD. If an entity is both a SUBLICENSEE AND A CORPORATE
PARTNER, any payment made by such entity to COMPANY or its AFFILIATES shall be
counted only once when calculating the amount to be paid to M.I.T. hereunder,
regardless of whether such payment could be classified as both SUBLICENSE INCOME
AND CORPORATE PARTNER INCOME.

            (f)   NO MULTIPLE ROYALTIES.

                  (i)   If

                        (a)   the manufacture, use, lease, or sale of any
LICENSED PRODUCT or the performance of any LICENSED PROCESS is covered by more
than one of the PATENT RIGHTS; or

                        (b)   the manufacture, use, lease or sale of a LICENSED
PRODUCT involves the performance of a LICENSED PROCESS,

            then multiple royalties shall NOT be due and COMPANY shall pay to
M.I.T. the lowest applicable royalty.

                  (ii)  In the event that COMPANY is obligated to pay any
portion of any SUBLICENSE INCOME or CORPORATE PARTNER INCOME to a third party
for intellectual property rights that are necessary for COMPANY's sale of
LICENSED PRODUCTS and/or LICENSED PROCESSES, then COMPANY may deduct [**]
([**]%) of the amounts paid to such third party from the amount due to M.I.T.
pursuant to Section 4.1(f); provided, however that said amounts paid to M.I.T.
pursuant to Section 4.1(f) may not be reduced below [**] percent ([**]%) in any
REPORTING PERIOD.

                                       16
<Page>

            (g)   EQUITY.

                  (i)   INITIAL GRANT. COMPANY acknowledges that on the ORIGINAL
EFFECTIVE DATE it issued a total of One Hundred and Twenty Thousand Five Hundred
and Thirty-Three (120,533) shares of Common Stock of COMPANY, $.0001 par value
per share, (the "Shares") in the name of M.I.T. and those individuals listed on
APPENDIX G (the "M.I.T. Holders") in the amounts specified in Appendix G subject
to the following terms and conditions:

                  COMPANY's obligation to issue the Shares:
                  (A) to M.I.T. was conditioned upon prior receipt from M.I.T.
                      of an investment letter, a First Amendment to Right of
                      First Refusal and Co-Sale Agreement, and a Voting
                      Agreement, in substantially the forms attached hereto,
                      respectively, as Exhibit C, Exhibit D, and Exhibit E; and

                  (B) to each M.I.T. Holder was conditioned upon prior receipt
                      from each such M.I.T. Holder of an investment letter, a
                      First Amendment to Right of First Refusal and CoSale
                      Agreement, and a Voting Agreement, in substantially the
                      forms attached hereto, respectively, as Exhibit C, Exhibit
                      D, and Exhibit E.

                  COMPANY represents to M.I.T. that, as of the ORIGINAL
EFFECTIVE DATE, the aggregate number of Shares equaled Five Percent (5%) of the
COMPANY's issued and outstanding Common Stock calculated on a "Fully Diluted
Basis." For purposes of this Section 4.1(g), "Fully Diluted Basis" means that
the total number of issued and outstanding shares of the COMPANY's Common Stock
was calculated to include conversion of all issued and outstanding securities
then convertible into common stock, the exercise of all then outstanding options
and warrants to purchase shares of common stock, whether or not then
exercisable, and assumed the issuance of UNGRANTED OPTIONS.

                  (ii)  ANTI-DILUTION PROTECTION. COMPANY represents it issued
additional shares of Common Stock to M.I.T. and each M.I.T. Holder pro rata,
such that M.I.T.'s and each M.I.T. Holders' ownership of outstanding Common
Stock in the aggregate did not fall below Five Percent (5%) on a Fully Diluted
Basis, as calculated after giving effect to the anti-dilutive issuance. Such
issuances occurred on the date upon which COMPANY received a total of Five
Million Dollars ($5,000,000) in cash in exchange for COMPANY's capital stock.
(the

                                       17
<Page>

"Funding Threshold"). No additional shares shall be due to M.I.T. or any M.I.T.
Holder pursuant to this Agreement.

                  (iii) PARTICIPATION IN FUTURE PRIVATE EQUITY OFFERINGS.
COMPANY represents it has amended its Series A Convertible Preferred Stock and
Warrant Purchase Agreement (CSWP) to add M.I.T. (but not the M.I.T. Holders) as
a "Purchaser" for purposes of Section 7 thereof (Participation Rights) with
respect to offerings of New Securities (as defined therein) after the date of
the Funding Threshold. This Amendment is attached as Exhibit F to this
Agreement. M.I.T. agreed to be bound by the terms and conditions of the CSWP
agreement insofar as they relate to Section 7 thereof. The Participation Rights
granted to M.I.T. pursuant to the Series A Convertible Preferred Stock and
Warrant Purchase Agreement shall terminate immediately prior to a firm
commitment for an underwritten public offering of the COMPANY's common stock
resulting in gross proceeds to the COMPANY of at least Ten Million dollars
($10,000,000).

     4.2 PAYMENTS.

            (a)   METHOD OF PAYMENT. All payments under this Agreement should be
made payable to "Massachusetts Institute of Technology" and sent to the address
identified in Section 14.1. Each payment should reference this Agreement and
identify the obligation under this Agreement that the payment satisfies.

            (b)   PAYMENTS IN U.S. DOLLARS. All payments due under this
Agreement shall be drawn on a United States bank and shall be payable in United
States dollars. Conversion of foreign currency to U.S. dollars shall be made at
the conversion rate existing in the United States (as reported in the WALL
STREET JOURNAL) on the last working day of the calendar quarter of the
applicable REPORTING PERIOD. Such payments shall be without deduction of
exchange, collection, or other charges, and, specifically, without deduction of
withholding or similar taxes or other government imposed fees or taxes, except
as permitted in the definition of NET SALES.

            (c)   LATE PAYMENTS. Any payments by COMPANY that are not paid on or
before the date such payments are due under this Agreement shall bear interest,
to the extent permitted by law, at two percentage points above the Prime Rate of
interest as reported in the WALL STREET JOURNAL on the date payment is due.

                                       18
<Page>

                             5. REPORTS AND RECORDS.

     5.1 FREQUENCY OF REPORTS.

            (a)   BEFORE FIRST COMMERCIAL SALE. Prior to the first commercial
sale of any LICENSED PRODUCT or first commercial performance of any LICENSED
PROCESS, COMPANY shall deliver reports to M.I.T. annually, within sixty (60)
days after the end of each calendar year, containing information concerning the
immediately preceding calendar year, as further described in Section 5.2.

            (b)   UPON FIRST COMMERCIAL SALE OF A LICENSED PRODUCT OR DISCOVERED
PRODUCT OR COMMERCIAL PERFORMANCE OF A LICENSED PROCESS. COMPANY shall report to
M.I.T. the date of first commercial sale of a LICENSED PRODUCT, the date of
first commercial sale of a DISCOVERED PRODUCT and the date of first commercial
performance of a LICENSED PROCESS within sixty (60) days after occurrence in
each country.

            (c)   AFTER FIRST COMMERCIAL SALE. After the first commercial sale
of a LICENSED PRODUCT or first commercial performance of a LICENSED PROCESS,
COMPANY shall deliver reports to M.I.T. within sixty (60) days after the end of
each REPORTING PERIOD, containing information concerning the immediately
preceding REPORTING PERIOD, as further described in Section 5.2.

            (d)   For each LICENSED PRODUCT or LICENSED PROCESS for which NET
SALES have been received, COMPANY shall report to the reasonable best of its
ability which of the PATENT RIGHTS of this Agreement COVER the particular
LICENSED PRODUCT or LICENSED PROCESS sold. COMPANY shall also require that its
SUBLICENSEES so report. The information reported under this Section 5.1(d) shall
be for MIT administrative purposes only and shall have no bearing on the
royalties paid hereunder.

     5.2 CONTENT OF REPORTS AND PAYMENTS. Each report delivered by COMPANY to
M.I.T. shall contain at least the following information for the immediately
preceding REPORTING PERIOD:

            (a)   the number of LICENSED PRODUCTS sold, leased or distributed by
COMPANY, its AFFILIATES, CORPORATE PARTNERS and SUBLICENSEES to independent
third parties in each country, and, if applicable, the number of LICENSED

                                       19
<Page>

PRODUCTS used by COMPANY, its AFFILIATES, CORPORATE PARTNERS and SUBLICENSEES in
the provision of services in each country;

            (b)   a description of LICENSED PROCESSES performed by COMPANY, its
AFFILIATES, CORPORATE PARTNERS and SUBLICENSEES in each country as may be
pertinent to a royalty accounting hereunder;

            (c)   the gross price charged by COMPANY, its AFFILIATES, CORPORATE
PARTNERS and SUBLICENSEES for each LICENSED PRODUCT and, if applicable, the
gross price charged for each LICENSED PRODUCT used to provide services in each
country; and the gross price charged for each LICENSED PROCESS performed by
COMPANY, its AFFILIATES, CORPORATE PARTNERS and SUBLICENSEES in each country;

            (d)   calculation of NET SALES for the applicable REPORTING PERIOD
in each country, including a listing of applicable deductions;

            (e)   total royalty payable on NET SALES in U.S. dollars, together
with the exchange rates used for conversion;

            (f)   the amount of SUBLICENSE INCOME received by COMPANY from each
SUBLICENSEE and the amount due to M.I.T. from such SUBLICENSE INCOME, including
an itemized breakdown of the sources of income comprising the SUBLICENSE INCOME;
and

            (g)   the amount of CORPORATE PARTNER INCOME received by COMPANY
from each CORPORATE PARTNER and the amount due to M.I.T. from such CORPORATE
PARTNER INCOME, including an itemized breakdown of the sources of income
comprising the CORPORATE PARTNER INCOME;

            (h)   the number of sublicenses entered into for the PATENT RIGHTS,
LICENSED PRODUCTS, DISCOVERED PRODUCTS and/or LICENSED PROCESSES; and

            (i)   the number of CORPORATE PARTNER agreements entered into for
the REPORTING PERIOD.

            If no amounts are due to M.I.T. for any REPORTING PERIOD, the report
shall so state.

                                       20
<Page>

     5.3 FINANCIAL STATEMENTS. On or before the ninetieth (90th) day following
the close of COMPANY's fiscal year, COMPANY shall provide M.I.T. with COMPANY's
financial statements for the preceding fiscal year including, at a minimum, a
balance sheet and an income statement, certified by COMPANY's treasurer or chief
financial officer or by an independent auditor.

     5.4 RECORDS. COMPANY shall maintain, and shall cause its AFFILIATES and
SUBLICENSEES to maintain, complete and accurate records relating to the rights
and obligations under this Agreement and any amounts payable to M.I.T. in
relation to this Agreement, which records shall contain sufficient information
to permit M.I.T. to confirm the accuracy of any reports delivered to M.I.T. and
compliance in other respects with this Agreement. The relevant party shall
retain such records for at least five (5) years following the end of the
calendar year to which they pertain, during which time M.I.T., or M.I.T.'s
appointed agents, shall have the right, at M.I.T.'s expense, to inspect such
records during normal business hours, upon at least five (5) business days prior
notice to verify any reports and payments made or compliance in other respects
under this Agreement. In the event that any audit performed under this Section
reveals an underpayment in excess of five percent (5%), COMPANY shall bear the
full cost of such audit and shall remit any amounts due to M.I.T. within thirty
(30) days after receiving notice thereof from M.I.T.

     5.5 CONFIDENTIAL INFORMATION. The information in the reports and records
provided by COMPANY to M.I.T. pursuant to Sections 5.1 through 5.4 of this
Agreement and in the sublicense agreements provided to M.I.T. under Section
2.3(b) shall be considered "Confidential Information", provided that such
information is specifically designated in writing as confidential. M.I.T. shall
maintain the Confidential Information in strict confidence, unless, the
information (i) was in the public domain prior to the time of its disclosure
under this Agreement; (ii) entered the public domain after the time of its
disclosure under this Agreement through means other than an unauthorized
disclosure resulting from an act or omission by M.I.T; (iii) was independently
developed or discovered by M.I.T. without use of the Confidential Information;
(iv) is or was disclosed to M.I.T. at any time, whether prior to or after the
time of its disclosure under this Agreement, by a third party having no
fiduciary relationship with COMPANY and having no obligation of confidentiality
with respect to such Confidential Information; or (v) is required to be
disclosed to comply with applicable laws or regulations, or with a court or
administrative order.

                                       21
<Page>

                             6. PATENT PROSECUTION.

     6.1 RESPONSIBILITY FOR PATENT RIGHTS. M.I.T. shall prepare, file,
prosecute, and maintain all of the PATENT RIGHTS. However, M.I.T. at its own
discretion may abandon any of the foreign rights for PATENT RIGHTS CASE [**] and
PATENT RIGHTS CASE [**] BACKGROUND at any time, subject to Section 6.2 below,
and may abandon any of the U.S. patents of these same PATENT RIGHTS after [**],
subject to Section 6.2 below. M.I.T. may also abandon any PATENT RIGHTS
HEPARINASE at any time, subject to Section 6.2 below. COMPANY shall have
reasonable opportunities to advise M.I.T. and shall cooperate with M.I.T. in
such preparation, filing, prosecution and maintenance. M.I.T. will instruct its
patent attorney to copy COMPANY on all patent prosecution documents relating to
PATENT RIGHTS during the TERM.

     6.2 ABANDONING PATENT RIGHTS. Should M.I.T. elect to abandon any of PATENT
RIGHTS CASE [**], PATENT RIGHTS CASE [**] BACKGROUND or PATENT RIGHTS
HEPARINASE, M.I.T. will first notify COMPANY of its intent to do so, and COMPANY
may require that M.I.T. continue prosecution or maintenance of such patent(s)
provided that COMPANY agrees to reimburse all of M.I.T.'s related expenses
including any related interference expenses.

     6.3 INTERNATIONAL (NON-UNITED STATES) FILINGS. APPENDIX F is a list of the
countries in which patent applications corresponding to the United States patent
applications listed in APPENDICES A THRU E shall be filed, prosecuted, and
maintained. APPENDIX F may be amended by mutual agreement of COMPANY and M.I.T.

     6.4 PAYMENT OF EXPENSES. Payment of all fees and costs supported by an
invoice, including attorneys' fees, relating to the filing, prosecution and
maintenance of PATENT RIGHTS HEPARIN shall be the responsibility of COMPANY,
whether such amounts were incurred before or after the ORIGINAL EFFECTIVE DATE.
As of October 1, 2001, M.I.T. had incurred approximately [**] dollars ($[**])
for such patent-related fees and costs ("EXISTING EXPENSES"). COMPANY shall
reimburse M.I.T. for the EXISTING EXPENSES incurred prior to the ORIGINAL
EFFECTIVE DATE in three equal installments. The first installment was due on,
and M.I.T. acknowledges that it was paid on, the ORIGINAL EFFECTIVE DATE; the
second installment shall be due one year after the ORIGINAL EFFECTIVE DATE; and
the remaining payment shall be due two years from the ORIGINAL EFFECTIVE DATE.
In addition, M.I.T. shall bill COMPANY for COMPANY'S pro rata share of the costs
for PATENT

                                       22
<Page>

RIGHTS HEPARINASE incurred after the ORIGINAL EFFECTIVE DATE, said share being
equal to the shares of other active licensees for PATENT RIGHTS HEPARINASE.
     COMPANY shall reimburse all amounts due pursuant to this Section within
thirty (30) days after invoicing; late payments shall accrue interest pursuant
to Section 4.2(c). In all instances, M.I.T. shall pay the fees prescribed for
large entities to the United States Patent and Trademark Office. Notwithstanding
the first sentence of this Section, in the event M.I.T. exclusively licenses any
of the PATENT RIGHTS described in Section 2.2 in a different field of use to a
third party, M.I.T. shall promptly notify COMPANY in writing and such fees and
costs associated with those PATENT RIGHTS shall be allocated in a fair and
equitable manner between COMPANY and a subsequent licensee on a go-forward
basis.

                                7. INFRINGEMENT.

     7.1 NOTIFICATION OF INFRINGEMENT. Each party agrees to provide written
notice to the other party promptly after becoming aware of any infringement of
the PATENT RIGHTS.

     7.2 RIGHT TO PROSECUTE INFRINGEMENTS.

            (a)   COMPANY RIGHT TO PROSECUTE PATENT RIGHTS IN EXCLUSIVE FIELDS.
So long as COMPANY remains the exclusive licensee of PATENT RIGHTS HEPARIN in
FIELD ALL BUT MACHINES, COMPANY, to the extent permitted by law, shall have the
right, under its own control and at its own expense, to prosecute any third
party infringement of PATENT RIGHTS HEPARIN in FIELD ALL BUT MACHINES, subject
to Sections 7.4 and 7.5. In addition, so long as COMPANY remains the exclusive
licensee of PATENT RIGHTS HEPARINASE in FIELD MANUFACTURING, COMPANY, to the
extent permitted by law, shall have the right, under its own control and at its
own expense, to prosecute any third party infringement of PATENT RIGHTS
HEPARINASE in FIELD MANUFACTURING, subject to Sections 7.4 and 7.5. If required
by law, M.I.T. shall permit any action under this Section to be brought in its
name, including being joined as a party-plaintiff, provided that COMPANY shall
hold M.I.T. harmless from, and indemnify M.I.T. against, any costs, expenses, or
liability that M.I.T. incurs in connection with such action. Prior to commencing
any such action, COMPANY shall consult with M.I.T. and shall consider the views
of M.I.T. regarding the advisability of the proposed action and its effect on
the public interest. COMPANY shall not enter into any settlement, consent
judgment, or other voluntary final disposition of any infringement action under
this Section without the prior written consent of M.I.T.

                                       23
<Page>

     (b)    M.I.T. RIGHT TO PROSECUTE PATENT RIGHTS IN EXCLUSIVE FIELDS. In the
event that COMPANY is unsuccessful in persuading the alleged infringer of PATENT
RIGHTS HEPARIN in FIELD ALL BUT MACHINES or PATENT RIGHTS HEPARINASE in FIELD
MANUFACTURING to desist or fails to have initiated an infringement action within
a reasonable time after COMPANY first becomes aware of the basis for such
action, M.I.T. shall have the right, to prosecute such infringement under its
sole control and at its sole expense, and any recovery obtained shall belong to
M.I.T. If required by law, COMPANY hereby agrees that M.I.T. may include COMPANY
as a party-plaintiff in any such suit, without expense to COMPANY. Prior to
commencing any such action, M.I.T. shall consult with COMPANY and shall consider
the views of COMPANY regarding the advisability of the proposed action. Further,
M.I.T. shall not enter into any settlement, consent judgment, or other voluntary
final disposition of any infringement action under this Section without first
consulting with and considering the views of COMPANY. Notwithstanding the
forgoing, any action taken under this Section shall be at the sole discretion of
M.I.T.

     (c)    M.I.T. RIGHT TO PROSECUTE PATENT RIGHTS IN NON-EXCLUSIVE FIELDS.
M.I.T. shall have the right, but shall not be obligated, to prosecute at its
sole control and sole expense all infringements of PATENT RIGHTS other than
PATENT RIGHTS HEPARIN in FIELD ALL BUT MACHINES or PATENT RIGHTS HEPARINASE in
FIELD MANUFACTURING, and M.I.T. shall keep any recovery or damages derived
therefrom, whether compensatory for past infringement or punitive. If required
by law, COMPANY hereby agrees that M.I.T. may include COMPANY as a party
plaintiff in any such suit, without expense to COMPANY. Prior to commencing any
such action, M.I.T. shall consult with COMPANY and shall consider the views of
COMPANY regarding the advisability of the proposed action. Further, M.I.T. shall
not enter into any settlement, consent judgment, or other voluntary final
disposition of any infringement action under this Section without first
consulting with and considering the views of COMPANY. Lastly, in the event that
COMPANY approaches M.I.T. and requests that M.I.T. commence the prosecution of
an infringement of any of the PATENT RIGHTS other than the PATENT RIGHTS HEPARIN
in FIELD ALL BUT MACHINES and the PATENT RIGHTS HEPARINASE in FIELD
MANUFACTURING, M.I.T. agrees to give due consideration to the views of the
COMPANY. Notwithstanding the forgoing, any action taken under this Section shall
be at the sole discretion of M.I.T.

     7.3 DECLARATORY JUDGMENT ACTIONS. In the event that a declaratory judgment
action is brought against M.I.T. or COMPANY by a third party alleging
invalidity, unenforceability, or non-infringement of the PATENT RIGHTS, M.I.T.,
at its option, shall have the right within

                                       24
<Page>

twenty (20) days after commencement of such action to take over the sole defense
of the action at its own expense. If M.I.T. does not exercise this right,
COMPANY may take over the sole defense of the action at COMPANY's sole expense,
subject to Sections 7.4 and 7.5.

     7.4 OFFSETS. COMPANY may offset a total of [**] percent ([**]%) of any
expenses incurred under Sections 7.2 and 7.3 against any payments due to M.I.T.
under Article 4, provided that in no event shall such payments under Article 4,
when aggregated with any other offsets and credits allowed under this Agreement,
be reduced by more than [**] percent ([**]%) in any REPORTING PERIOD, it being
understood that any expenses which COMPANY is prevented by the foregoing proviso
from offsetting, in any REPORTING PERIOD may be carried forward and offset in
one or more subsequent REPORTING PERIODS (applying the foregoing proviso in each
subsequent REPORTING PERIOD).

     7.5 RECOVERY. Any recovery obtained in an action brought by COMPANY under
Sections 7.2 or 7.3 shall be distributed as follows: (i) each party shall be
reimbursed for any expenses incurred in the action (including the amount of any
royalty or other payments withheld from M.I.T. as described in Section 7.4),
(ii) as to ordinary damages, COMPANY shall receive an amount equal to its lost
profits or a reasonable royalty on the infringing sales, or whichever measure of
damages the court shall have applied, and COMPANY shall pay to M.I.T. based upon
such amount the portion thereof representing a reasonable approximation of the
royalties and other amounts that COMPANY would have paid to M.I.T. if COMPANY
had sold the infringing products, processes and services rather than the
infringer, and (iii) as to special or punitive damages, the parties shall [**].

     7.6 COOPERATION. Each party agrees to cooperate in any action under this
Article, which is controlled by the other party, provided that the controlling
party reimburses the cooperating party promptly for any costs and expenses
incurred by the cooperating party in connection with providing such assistance.

     7.7 RIGHT TO SUBLICENSE. So long as COMPANY remains the exclusive licensee
of the PATENT RIGHTS HEPARIN in in FIELD ALL BUT MACHINES or PATENT RIGHTS
HEPARINASE in FIELD MANUFACTURING, COMPANY shall have the sole right to
sublicense to any alleged infringer for future use of PATENT RIGHTS HEPARIN in
FIELD ALL BUT MACHINES or PATENT RIGHTS HEPARINASE in FIELD MANUFACTURING, as
the case may be, in accordance with the terms and conditions of this Agreement
relating to sublicenses. Any upfront fees as part of such sublicense [**]; other
revenues to COMPANY pursuant to such sublicense shall be treated as set forth in
Article 4.

                                       25
<Page>

                        8. INDEMNIFICATION AND INSURANCE.

     8.1 INDEMNIFICATION.

            (a)   INDEMNITY. COMPANY shall indemnify, defend, and hold harmless
M.I.T. and its trustees, officers, faculty, students, employees, and agents and
their respective successors, heirs and assigns (the "Indemnitees"), against any
liability, damage, loss, or expense (including reasonable attorneys fees and
expenses) (collectively, "Losses") incurred by or imposed upon any of the
Indemnitees in connection with any claims, suits, actions, demands or judgments
arising out of any theory of liability (including without limitation actions in
the form of tort, warranty, or strict liability and regardless of whether such
action has any factual basis) concerning any product, process, or service that
is made, used, sold, imported, or performed pursuant to any right or license
granted under this Agreement; provided, however, that COMPANY shall have no
obligation pursuant to the foregoing with respect to any Losses that result from
the gross negligence or willful misconduct of any Indemnitee.

            (b)   PROCEDURES. The Indemnitees agree to provide COMPANY with
prompt written notice of any claim, suit, action, demand, or judgment for which
indemnification is sought under this Agreement. COMPANY agrees, at its own
expense, to provide attorneys reasonably acceptable to M.I.T. to defend against
any such claim. The Indemnitees shall cooperate fully with COMPANY in such
defense and will permit COMPANY to conduct and control such defense and the
disposition of such claim, suit, or action (including all decisions relative to
litigation, appeal, and settlement); provided, however, that any Indemnitee
shall have the right to retain its own counsel, at the expense of COMPANY, if
representation of such Indemnitee by the counsel retained by COMPANY would be
inappropriate because of actual or potential differences in the interests of
such Indemnitee and any other party represented by such counsel. COMPANY agrees
to keep M.I.T. informed of the progress in the defense and disposition of such
claim and to consult with M.I.T. with regard to any proposed settlement.

     8.2 INSURANCE. Before the first human use of a LICENSED PRODUCT or LICENSED
PROCESS, COMPANY shall obtain and carry in full force and effect commercial
general liability insurance, including product liability and errors and
omissions insurance which shall protect COMPANY and Indemnitees with respect to
events covered by Section 8.1(a) above. Such insurance (i) shall be issued by an
insurer licensed to practice in the Commonwealth of Massachusetts or an insurer
pre-approved by M.I.T., such approval not to be unreasonably withheld, (ii)
shall list M.I.T. as an additional insured thereunder, (iii) shall be endorsed
to

                                       26
<Page>

include product liability coverage, and (iv) shall require thirty (30) days
written notice to be given to M.I.T. prior to any cancellation or material
change thereof. The limits of such insurance shall not be less than One Million
Dollars ($1,000,000) per occurrence with an aggregate of Three Million Dollars
($3,000,000) for bodily injury including death; One Million Dollars ($1,000,000)
per occurrence with an aggregate of Three Million Dollars ($3,000,000) for
property damage; and One Million Dollars ($1,000,000) per occurrence with an
aggregate of Three Million Dollars ($3,000,000) for errors and omissions. In the
alternative, COMPANY may self-insure subject to prior approval of M.I.T. COMPANY
shall provide M.I.T. with Certificates of Insurance evidencing compliance with
this Section. COMPANY shall continue to maintain such insurance or
self-insurance after the expiration or termination of this Agreement during any
period in which COMPANY or any AFFILIATE or SUBLICENSEE continues (i) to make,
use, or sell a product that was a LICENSED PRODUCT under this Agreement or (ii)
to perform a service that was a LICENSED PROCESS under this Agreement, and
thereafter for a period of five (5) years.

                        9. REPRESENTATIONS AND WARRANTIES

     M.I.T. hereby represents and warrants that, to the best of its knowledge on
the EFFECTIVE DATE: (i) it is the sole owner of all PATENT RIGHTS other than the
PATENT RIGHTS for M.I.T. Case [**], which are jointly owned by M.I.T. and the
[**], and the PATENT RIGHTS for M.I.T. Case [**], which are owned jointly by
M.I.T. and [**], and (ii) has the right to grant the licenses granted herein.
M.I.T.'s total liability under the representations and warranties of this
Agreement shall be limited to an amount equal to the total sum that has been
paid by COMPANY to M.I.T. under the provisions of Article 4 of this Agreement
and any payments that have been made by COMPANY to M.I.T. for the EXISTING
EXPENSES described in Section 6.4.

     EXCEPT AS MAY OTHERWISE BE EXPRESSLY SET FORTH IN THIS AGREEMENT, M.I.T.
MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE PATENT RIGHTS,
EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, NONINFRINGEMENT, VALIDITY OF PATENT RIGHTS
CLAIMS, WHETHER ISSUED OR PENDING, AND THE ABSENCE OF LATENT OR OTHER DEFECTS,
WHETHER OR NOT DISCOVERABLE. Specifically, and not to limit the foregoing,
M.I.T. makes no warranty or representation (i) regarding the validity or scope
of the PATENT RIGHTS, and (ii) that the exploitation of the PATENT RIGHTS or any
LICENSED

                                       27
<Page>

PRODUCT or LICENSED PROCESS will not infringe any patents or other intellectual
property rights of M.I.T. or of a third party.

     IN NO EVENT SHALL EITHER PARTY, ITS TRUSTEES, DIRECTORS, OFFICERS,
EMPLOYEES AND AFFILIATES BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES OF
ANY KIND ARISING OUT OF THIS AGREEMENT, EXCEPT AS OTHERWISE PROVIDED IN
PARAGRAPH 8. 1, OR FOR INJURY TO PROPERTY AND LOST PROFITS, REGARDLESS OF
WHETHER SUCH PARTY SHALL BE ADVISED, SHALL HAVE OTHER REASON TO KNOW, OR IN FACT
SHALL KNOW OF THE POSSIBILITY OF THE FOREGOING.

                                 10. ASSIGNMENT.

     This Agreement is personal to COMPANY and no rights or obligations may be
assigned by COMPANY, except that COMPANY may assign this Agreement, upon written
notice to M.I.T. and without M.I.T.'s consent, in conjunction with the sale or
transfer of all or substantially all of its assets related to the
commercialization of the PATENT RIGHTS, or pursuant to a merger or
consolidation, to or into an entity which has agreed in writing to be bound by
all the terms and conditions of this Agreement. Failure of the assignee to so
agree shall be grounds for termination by M.I.T.

                        11. GENERAL COMPLIANCE WITH LAWS.

     11.1 COMPLIANCE WITH LAWS. COMPANY shall use reasonable commercial efforts
to comply with all commercially material local, state, federal, and
international laws and regulations relating to the development, manufacture,
use, and sale of LICENSED PRODUCTS and LICENSED PROCESSES.

     11.2 EXPORT CONTROL. COMPANY and its AFFILIATES and SUBLICENSEES shall
comply with all United States laws and regulations controlling the export of
certain commodities and technical data, including without limitation all Export
Administration Regulations of the United States Department of Commerce. Among
other things, these laws and regulations prohibit or require a license for the
export of certain types of commodities and technical data to specified
countries. COMPANY hereby gives written assurance that it will comply with, and
will cause its AFFILIATES and SUBLICENSEES to comply with, all United States
export control laws and regulations, that it bears sole responsibility for any
violation of such laws and

                                       28
<Page>

regulations by itself or its AFFILIATES or SUBLICENSEES, and that it will
indemnify, defend, and hold M.I.T. harmless (in accordance with Section 8.1) for
the consequences of any such violation.

     11.3 NON-USE OF M.I.T. NAME. COMPANY and its AFFILIATES and SUBLICENSEES
shall not use the name of "Massachusetts Institute of Technology," "Lincoln
Laboratory" or any variation, adaptation, or abbreviation thereof, or of any of
its trustees, officers, faculty, students, employees, or agents (collectively,
"M.I.T. Associates"), or any trademark owned by M.I.T., or any terms of this
Agreement, in any promotional material or other public announcement or
disclosure without the prior written consent of M.I.T., or in the case of the
name of any M.I.T. Associate, the written consent of such M.I.T. Associate. The
foregoing notwithstanding, without the consent of M.I.T., COMPANY may state that
it is licensed by M.I.T. under one or more of the patents and/or patent
applications comprising the PATENT RIGHTS, may make statements of facts,
including of past or present employment or consulting relationships, and may
make disclosures or statements required by law.

     11.4 MARKING OF LICENSED PRODUCTS. To the extent commercially feasible and
consistent with prevailing business practices, COMPANY shall mark, and shall
cause its AFFILIATES and SUBLICENSEES to mark, all LICENSED PRODUCTS that are
manufactured or sold under this Agreement with the number of each issued patent
under the PATENT RIGHTS that applies to such LICENSED PRODUCT.

                                12. TERMINATION.

     12.1 VOLUNTARY TERMINATION BY COMPANY. COMPANY shall have the right to
terminate this Agreement, for any reason, (i) upon at least six (6) months prior
written notice to M.I.T., such notice to state the date at least six (6) months
in the future upon which termination is to be effective, and (ii) upon payment
of all amounts due to M.I.T. through such termination effective date. In
addition, by providing three (3) months written notice, COMPANY may separately
terminate its license to PATENT RIGHTS CASE [**] and PATENT RIGHTS CASE [**]
BACKGROUND.

     12.2 CESSATION OF BUSINESS. If COMPANY ceases to carry on its business
related to this Agreement, M.I.T. shall have the right to terminate this
Agreement immediately upon written notice to COMPANY.

     12.3 TERMINATION FOR DEFAULT.

                                       29
<Page>

            (a)   NONPAYMENT. In the event COMPANY fails to pay any amounts due
and payable to M.I.T. hereunder, and fails to make such payments within sixty
(60) days after receiving written notice of such failure, provided such notice
expressly refers to this Section 12.3 and M.I.T.'s right of termination, M.I.T.
may terminate this Agreement immediately upon written notice to COMPANY.

            (b)   MATERIAL BREACH. In the event COMPANY commits a material
breach of its obligations under this Agreement, except for breach as described
in Section 3.1 or 12.3(a), and fails to cure that breach within ninety (90) days
after receiving written notice thereof, provided such notice expressly refers to
this Section 12.3 and M.I.T.'s right of termination, M.I.T. may terminate this
Agreement immediately upon written notice to COMPANY.

     12.4 EFFECT OF TERMINATION.

            (a)   SURVIVAL. The following provisions shall survive the
expiration or termination of this Agreement: Articles 1, 8, 9, 13 and 14, and
Sections 2.3 (c), 5.2 (obligation to provide final report and payment), 5.4,
5.5, 11.1, 11.2 and 12.4

            (b)   INVENTORY. Upon the early termination of this Agreement,
COMPANY and its AFFILIATES and SUBLICENSEES may complete and sell any
work-in-progress and inventory of LICENSED PRODUCTS that exist as of the
effective date of termination, provided that (i) COMPANY pays M.I.T. the
applicable running royalty or other amounts due on such sales of LICENSED
PRODUCTS in accordance with the terms and conditions of this Agreement, and (ii)
COMPANY and its AFFILIATES and SUBLICENSEES shall complete and sell all
work-in-progress and inventory of LICENSED PRODUCTS within six (6) months after
the effective date of termination.

            (c)   PRE-TERMINATION OBLIGATIONS. In no event shall termination of
this Agreement release COMPANY, AFFILIATES, or SUBLICENSEES from the obligation
to pay any amounts that became due on or before the effective date of
termination.

                             13. DISPUTE RESOLUTION.

     13.1 MANDATORY PROCEDURES. The parties agree that any dispute arising out
of or relating to this Agreement shall be resolved solely by means of the
procedures set forth in this Article, and that such procedures constitute
legally binding obligations that are an essential provision of

                                       30
<Page>

this Agreement. If either party fails to observe the procedures of this Article,
as may be modified by their written agreement, the other party may bring an
action for specific performance of these procedures in any court of competent
jurisdiction.

     13.2 EQUITABLE REMEDIES. Although the procedures specified in this Article
are the sole and exclusive procedures for the resolution of disputes arising out
of or relating to this Agreement, either party may seek a preliminary injunction
or other provisional equitable relief if, in its reasonable judgment, such
action is necessary to avoid irreparable harm to itself or to preserve its
rights under this Agreement.

     13.3 DISPUTE RESOLUTION PROCEDURES.

            (a)   MEDIATION. In the event any dispute arising out of or relating
to this Agreement remains unresolved within sixty (60) days from the date the
affected party informed the other party of such dispute, either party may
initiate mediation upon written notice to the other party ("Notice Date"),
whereupon both parties shall be obligated to engage in a mediation proceeding
under the then current Center for Public Resources ("CPR") Model Procedure for
Mediation of Business Disputes (http://www.cpradr.org), except that specific
provisions of this Article shall override inconsistent provisions of the CPR
Model Procedure. The mediator will be selected from the CPR Panels of Neutrals.
If the parties cannot agree upon the selection of a mediator within fifteen (15)
business days after the Notice Date, then upon the request of either party, the
CPR shall appoint the mediator. The parties shall attempt to resolve the dispute
through mediation until the first of the following occurs: (i) the parties reach
a written settlement; (ii) the mediator notifies the parties in writing that
they have reached an impasse; (iii) the parties agree in writing that they have
reached an impasse; or (iv) the parties have not reached a settlement within
sixty (60) days after the Notice Date.

            (b)   TRIAL WITHOUT JURY. If the parties fail to resolve the dispute
through mediation, or if neither party elects to initiate mediation, each party
shall have the right to pursue any other remedies legally available to resolve
the dispute, provided, however, that the parties expressly waive any right to a
jury trial in any legal proceeding under this Article.

     13.4 PERFORMANCE TO CONTINUE. Each party shall continue to perform its
undisputed obligations under this Agreement pending final resolution of any
dispute arising out of or relating to this Agreement; provided, however, that a
party may suspend performance of its undisputed obligations during any period in
which the other party fails or refuses to perform its undisputed

                                       31
<Page>

obligations. Nothing in this Article is intended to relieve COMPANY from its
obligation to make undisputed payments pursuant to Articles 4 and 6 of this
Agreement.

     13.5 STATUTE OF LIMITATIONS. The parties agree that all applicable statutes
of limitation and time-based defenses (such as estoppel and laches) shall be
tolled while the procedures set forth in Sections 13.3(a) are pending. The
parties shall cooperate in taking any actions necessary to achieve this result.

                               14. MISCELLANEOUS.

     14.1 NOTICE. Any notices required or permitted under this Agreement shall
be in writing, shall specifically refer to this Agreement, and shall be sent by
hand, recognized national overnight courier, confirmed facsimile transmission,
confirmed electronic mail, or registered or certified mail, postage prepaid,
return receipt requested, to the following addresses or facsimile numbers of the
parties:

     If to M.I.T., all matters relating to the license:

                    Technology Licensing Office, Room NE25-230
                    Massachusetts Institute of Technology
                    77 Massachusetts Avenue
                    Cambridge, MA 02139-4307
                    Attention:  Director
                    Tel:  617-253-6966
                    Fax:  617-258-6790

     If to M.I.T., all matters relating to COMPANY equity:

                    Massachusetts Institute of Technology
                    Treasurer's Office
                    238 Main Street
                    Cambridge, MA 02142
                    Attention:  Phillips B. Moore
                    Tel:  617-253-5422
                    Fax:  617-258-6676

                                       32
<Page>

     If to COMPANY:

                    43 Moulton Street
                    Cambridge. MA 02138
                    Attention:  Chief Executive Officer
                    Tel: 617-491-9700
                    Fax: 617-491-9701

            All notices under this Agreement shall be deemed effective upon
receipt. A party may change its contact information immediately upon written
notice to the other party in the manner provided in this Section.

     14.2 GOVERNING LAW. This Agreement and all disputes arising out of or
related to this Agreement, or the performance, enforcement, breach or
termination hereof, and any remedies relating thereto, shall be construed,
governed, interpreted and applied in accordance with the laws of the
Commonwealth of Massachusetts, U.S.A., without regard to conflict of laws
principles, except that questions affecting the construction and effect of any
patent shall be determined by the law of the country in which the patent shall
have been granted.

     14.3 FORCE MAJEURE. Neither party will be responsible for delays resulting
from causes beyond the reasonable control of such party, including without
limitation fire, explosion, flood, war, acts of terrorism, strike, riot,
bankruptcy of third parties, or action, inaction or delay by any governmental
authority, provided that the nonperforming party uses commercially reasonable
efforts to avoid or remove such causes of nonperformance and continues
performance under this Agreement with reasonable dispatch whenever such causes
are removed.

     14.4 AMENDMENT AND WAIVER. This Agreement may be amended, supplemented, or
otherwise modified only by means of a written instrument signed by both parties.
Any waiver of any rights or failure to act in a specific instance shall relate
only to such instance and shall not be construed as an agreement to waive any
rights or fail to act in any other instance, whether or not similar.

     14.5 SEVERABILITY. In the event that any provision of this Agreement shall
be held invalid or unenforceable for any reason, such invalidity or
unenforceability shall not affect any other provision of this Agreement, and the
parties shall negotiate in good faith to modify this Agreement to preserve (to
the extent possible) their original intent. If the parties fail to reach a
modified agreement within thirty (30) days after the relevant provision is held
invalid or unenforceable, then the dispute shall be resolved in accordance with
the procedures set forth in

                                       33
<Page>

Article 13. While the dispute is pending resolution, this Agreement shall be
construed as if such provision were deleted by agreement of the parties.

     14.6 BINDING EFFECT. This Agreement shall be binding upon and inure to the
benefit of the parties and their respective permitted successors and assigns.

     14.7 HEADINGS. All headings are for convenience only and shall not affect
the meaning of any provision of this Agreement.

     14.8 ENTIRE AGREEMENT. This Agreement constitutes the entire agreement
between the parties with respect to its subject matter and supersedes all prior
agreements or understandings between the parties relating to its subject matter,
including, without limitation the ORIGINAL AGREEMENT.

     IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
by their duly authorized representatives.

THE EFFECTIVE DATE OF THIS AGREEMENT IS NOVEMBER 1, 2002

MASSACHUSETTS INSTITUTE OF                   MOMENTA PHARMACEUTICALS, INC.
TECHNOLOGY

By  /s/ LITA NELSEN                          By  /s/ S.K. WHORISKEY, PH.D.
   ------------------------------------         --------------------------------
Name   Lita L. Nelsen                        Name  Susan K Whoriskey
     ----------------------------------           ------------------------------
Title  Director, Technology Licensing        Title  Vice President, Licensing
       Office                                       and Business Development
       --------------------------------             ----------------------------

                                       34
<Page>

                                   APPENDIX A

     LIST OF PATENT APPLICATIONS AND PATENTS FOR THE PATENT RIGHTS CASE [**]


I.   UNITED STATES PATENTS AND APPLICATIONS

        M.I.T. CASE NO. [**]
        Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

II.  INTERNATIONAL (NON-U.S.) PATENTS AND APPLICATIONS


          M.I.T. CASE NO. [**]
          Entitled: [**]

            WO Application No. [**]
            Entitled: [**]

                                       35
<Page>

                                   APPENDIX B
     LIST OF PATENT APPLICATIONS AND PATENTS FOR THE PATENT RIGHTS CASE [**]
                                   BACKGROUND

I.  UNITED STATES PATENTS AND APPLICATIONS

        M.I.T. CASE NO. [**]
        Entitled: [**]

            USA Patent No. [**]
            Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

        M.I.T. CASE NO. [**]
        Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

        M.I.T. CASE NO. [**]
        Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

        M.I.T. CASE NO. [**]
        Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

II.  INTERNATIONAL (NON-U.S.) PATENTS AND APPLICATIONS

        M.I.T. CASE NO. [**]
        Entitled: [**]

            EPC Application No. [**]
            Entitled: [**]

            Japan Application No. [**]
            Entitled: [**]

            Canada Application No. [**]
            Entitled: [**]

                                       36
<Page>

        M.I.T. CASE NO. [**]
        Entitled: [**]

            EPC Application No. [**]
            Entitled:[**]
            Japan Application No. [**]
            Entitled: [**]

            Canada Application No. [**]
            Entitled: [**]

        M.I.T. CASE NO. [**]
        Entitled: [**]

            WO Application No. [**]
            Entitled: [**]

        M.I.T. CASE NO. [**]
        Entitled: [**]

            WO Application No. [**]
            Entitled: [**]

                                       37
<Page>

                                   APPENDIX C
      LIST OF PATENT APPLICATIONS AND PATENTS FOR THE PATENT RIGHTS HEPARIN

I.   UNITED STATES PATENTS AND APPLICATIONS

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            USA Serial No. [**]
            Entitled: [**]

                                       38
<Page>

II.  INTERNATIONAL (NON-U.S.) PATENTS AND APPLICATIONS

     M.I.T. CASE NO. [**]
     Entitled: [**]

            EPC Application No. [**]
            Entitled: [**]

            Canada Application No. [**]
            Entitled: [**]

            Japanese Application No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            EPC Application No. [**]
            Entitled: [**]

            Canada Application No. [**]
            Entitled: [**]

            Japanese Application No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            WO Application Serial No. [**]
            Entitled [**]

     M.I.T. CASE NO.[**]
     Entitled: [**]

            WO Application Serial No. [**]
            Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

            WO Application Serial No. [**]
            Entitled: [**]

                                       39
<Page>

                                   APPENDIX D

                            PATENT RIGHTS HEPARINASE

I.   UNITED STATES PATENTS AND APPLICATIONS

     M.I.T. CASE NO. [**]
     Entitled M.I.T. Case No. [**]

            USA Patent No. [**]
            Entitled [**]

            USA Patent No. [**]
            Entitled [**]

     M.I.T. CASE NO. [**]
     Entitled [**]

            USA Patent No. [**]
            Entitled [**]

            USA Patent No. [**]
            Entitled [**]

II.  INTERNATIONAL (NON-U.S.) PATENTS AND APPLICATIONS

     M.I.T. CASE NO. [**]
     Entitled [**]

            AT Patent No. [**].
            BE Patent No. [**]
            CH Patent No. [**]
            DE Patent No. [**].
            DK Patent No. [**]
            ES Patent No. [**]
            FR Patent No. [**]
            GB Patent No. [**].
            GR Patent No. [**]
            IE Patent No. [**]
            IT Patent No. [**]
            LI Patent No. [**]
            LU Patent No. [**]
            MC Patent No. [**]
            NL Patent No. [**]
            SE Patent No. [**]
            EP Patent No. [**]
            All Entitled: [**]

                                       40
<Page>

            CA Patent Application Serial No. [**]
            Entitled:  [**]

            JP Patent Application Serial No. [**]
            Entitled:  [**]

     M.I.T. CASE NO. [**]
     Entitled [**]

            EP Patent No. [**]
            Entitled:  [**]

            CA Patent No. [**].
            Entitled:  [**]

            JP Patent Application Serial No. [**]
            Entitled:  [**]

                                       41
<Page>

                                   APPENDIX E
      LIST OF PATENT APPLICATIONS AND PATENTS FOR THE PATENT RIGHTS MASSPEC

I.   UNITED STATES PATENTS AND APPLICATIONS

     M.I.T. CASE NO. [**]
     Entitled: [**]

         USA Patent No. [**]
         Entitled: [**]

                                       42
<Page>

                                   APPENDIX F

                             PCT Designating: [**].


                                       43
<Page>

                                   APPENDIX G

                                 M.I.T. HOLDERS

<Table>
<Caption>
                             Contact Information                    Shares
                             -------------------
<S>              <C>                                                     <C>
[**]             [**]                                                    [**]

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

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

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

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

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

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

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

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

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


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

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

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

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

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

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

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

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

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

[**]             [**]                                                    [**]
</Table>

                                       44
<Page>

                 FIRST AMENDMENT TO THE NOVEMBER 1, 2002 LICENSE

     This First Amendment, effective as of the date set forth above the
signatures of the parties below, pertains to the Amended and Restated Exclusive
Patent License Agreement, effective on November 1, 2002, by and between the
Massachusetts Institute of Technology ("M.I.T.") and Momenta Pharmaceuticals,
Inc. ("COMPANY").

     WHEREAS, M.I.T. is the owner of certain new intellectual property closely
related to the PATENT RIGHTS of the Amended and Restated Exclusive Patent
License Agreement and desires to have this technology developed and
commercialized to benefit the public; and

     WHEREAS, COMPANY desires to add this new technology to the PATENT RIGHTS
and M.I.T. is willing to grant a license thereunder.

     NOW, THEREFORE, M.I.T. and COMPANY hereby agree to modify the Amended and
Restated Exclusive Patent License Agreement as follows:

     1.   The following definitions shall be added to Section 1:

          "FIELD ENZYMES" shall mean all fields of use, except for use of the
          enzymes described in the PATENT RIGHTS ENZYMES as human therapeutics
          in pharmaceutical compositions and except for FIELD SEQUENCING
          MACHINES.

          "FIELD RESEARCH REAGENTS" shall mean the making, using and/or selling
          of enzymes and/or heparinases as reagents for research use by
          not-for-profit entities.

          "PATENT RIGHTS ENZYMES" shall mean the PATENT RIGHTS listed in
          APPENDIX H.

     2.   The definition of PATENT RIGHTS under Section 1.20 shall be modified
          to read:

          "PATENT RIGHTS" shall mean:

               (a)  the United States and international patents listed on
          APPENDICES A THROUGH E, AND H;

               (b)  the United States and international patent applications
          and/or provisional applications listed on APPENDICES A THROUGH E, AND
          H; and the resulting patents;

               (c)  any patent applications resulting from the provisional
                    applications listed on APPENDICES A THROUGH E, AND H; and
                    any divisionals,

<Page>

                    continuations, continuation-in-part applications, and
                    continued prosecution applications (and their relevant
                    international equivalents) of the patent applications listed
                    on APPENDICES A THROUGH E, AND H; and of such patent
                    applications that result from the provisional applications
                    listed on, APPENDICES A THROUGH E, AND H to the extent the
                    claims are directed to subject matter specifically described
                    in the patent applications listed on APPENDICES A THROUGH E,
                    AND H, and the resulting patents;

               (d)  any patents resulting from reissues, reexaminations, or
                    extensions (and their relevant international equivalents) of
                    the patents described in (a), (b), and (c) above; and

               (e)  international (non-United States) patent applications and
                    provisional applications filed after the ORIGINAL EFFECTIVE
                    DATE and the relevant international equivalents to
                    divisionals, continuations, continuation-in-part
                    applications and continued prosecution applications of the
                    patent applications to the extent the claims are directed to
                    subject matter specifically described in the patents or
                    patent applications referred to in (a), (b), (c), and (d)
                    above, and the resulting patents.

3.   M.I.T. hereby grants to COMPANY and its AFFILIATES for the TERM, a
     worldwide, royalty-bearing license to develop, make, have made, use, sell,
     offer to sell, lease, and import LICENSED PRODUCTS and to develop and
     perform LICENSED PROCESSES (which the parties acknowledge, may result in
     the identification of DISCOVERED PRODUCTS) under M.I.T.'s rights in the
     PATENT RIGHTS ENZYMES for FIELD ENZYMES.

4.   The last sentence of Section 2.1 shall be modified to read:

     Upon COMPANY's exercise of such right, the Appendix of this Agreement that
     describes the PATENT RIGHTS that dominate the IMPROVEMENT shall be deemed
     to have been amended to add the invention disclosure (and any related
     patent applications) covering such IMPROVEMENT, and such IMPROVEMENT and
     any resulting patent applications and patents shall thereafter be included
     in PATENT RIGHTS for all purposes of this Agreement, without any additional
     fee, other than the [**]Dollar fee referred to in the previous sentence,
     and M.I.T. shall provide COMPANY with an updated APPENDIX C, D OR H for its
     records.

5.   Section 2.2 shall be modified to read:

     2.2  EXCLUSIVITY. In order to establish an exclusive period for COMPANY and
     its AFFILIATES, M.I.T. agrees that it shall not grant any other license for
     (a) PATENTS RIGHTS HEPARIN in FIELD ALL BUT MACHINES, (b) PATENT RIGHTS
     HEPARINASE in FIELD MANUFACTURING, and (c) PATENT RIGHTS ENZYMES in FIELD
     ENZYMES, but specifically excluding FIELD RESEARCH REAGENTS, in

<Page>

     each case to develop, make, have made, use, sell, offer to sell, lease and
     import LICENSED PRODUCTS or to develop and perform LICENSED PROCESSES
     during the TERM.

6.   Section 4.1(c) shall be modified to read:

     (a)  RUNNING ROYALTIES DUE ON NET SALES BY COMPANY AND AFFILIATES. COMPANY
     shall pay to M.I.T. a running royalty of:

          (i)   [**] percent ([**]%) of NET SALES by COMPANY and AFFILIATES of
     LICENSED PRODUCTS or LICENSED PROCESSES which do not fall under any of the
     PATENT RIGHTS for M.I.T. CASES [**]; and

          (ii)  [**] percent ([**]%) of NET SALES by COMPANY and AFFILIATES of
LICENSED PRODUCTS or LICENSED PROCESSES which fall under any of the PATENT
RIGHTS for M.I.T. CASES [**];

     Running royalties shall be payable for each REPORTING PERIOD and shall be
due to M.I.T. within sixty (60) days after the end of each REPORTING PERIOD.

7.   Section 4.1(d) shall be modified to read:

     (a)  RUNNING ROYALTIES DUE ON NET SALES BY SUBLICENSEES. COMPANY shall pay
to M.I.T. a running royalty of:

          (i)   If the LICENSED PRODUCT or LICENSED PROCESS does NOT fall under
any of the PATENT RIGHTS for M.I.T. CASES [**]; the lesser of:

                (a)  [**] percent ([**]%) of NET SALES by SUBLICENSEES;

                                       or

                (b)  [**] percent ([**]%) of the royalty received by COMPANY
from SUBLICENSEES for NET SALES made by SUBLICENSEES;

                                       AND

          (ii)  If the LICENSED PRODUCT or LICENSED PROCESS falls under any of
the PATENT RIGHTS for M.I.T. CASES [**], the lesser of:

                (a)  [**] percent ([**]%) of NET SALES by SUBLICENSEES;

                                       or

                (b)  [**] percent ([**]%) of the royalty received by COMPANY
from SUBLICENSEES for NET SALES made by SUBLICENSEES

<Page>

          Running royalties shall be payable for each REPORTING PERIOD and shall
     be due to M.I.T. within sixty (60) days after the end of each REPORTING
     PERIOD.

8.   The patent rights of the following M.I.T. Case Nos. shall be added to the
PATENT RIGHTS ENZYMES and the PATENT RIGHTS, as defined by their inclusion in
the attached APPENDIX H:

     M.I.T. CASE NO. [**]
     Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

     M.I.T. CASE NO. [**]
     Entitled: [**]

9.   In consideration of the addition of the PATENT RIGHTS ENZYMES and the
license granted in the FIELD ENZYMES hereunder

          (a)   COMPANY shall pay M.I.T. a Patent Addition Fee of [**] dollars
          ($[**]) for each M.I.T. Case added for a total of [**] dollars
          ($[**]), which shall be due within thirty (30) days of the Effective
          Date of this First Amendment; and

          (b)   COMPANY shall be responsible for payment of all fees and costs
          relating to the filing, prosecution and maintenance of the patent
          rights of M.I.T. Case Nos. [**], whether such fees and costs were
          incurred [**] the Effective Date of this First Amendment; provided,
          however, that should M.I.T. license the PATENT RIGHTS ENZYMES to one
          or more third parties, M.I.T. shall promptly notify COMPANY in writing
          and any fees and costs associated with PATENT RIGHTS ENZYMES shall be
          allocated in a fair and equitable manner between COMPANY and any
          subsequent licensees of the PATENT RIGHTS ENZYMES on a go-forward
          basis.

10.  Section 7.2(a) shall be modified to read:

     COMPANY RIGHT TO PROSECUTE PATENT RIGHTS IN EXCLUSIVE FIELDS. So long as
     COMPANY remains the exclusive licensee of PATENT RIGHTS HEPARIN in FIELD
     ALL BUT MACHINES, COMPANY, to the extent permitted by law, shall have the
     right, under its own control and at its own expense, to prosecute any third
     party infringement of PATENT RIGHTS HEPARIN in FIELD ALL BUT MACHINES,
     subject to Sections 7.4 and 7.5. In addition, so long as COMPANY remains
     the exclusive licensee of PATENT RIGHTS HEPARINASE in FIELD MANUFACTURING,
     COMPANY, to the extent permitted by law, shall have the right, under its
     own control and at its own expense, to prosecute any third party
     infringement of PATENT RIGHTS HEPARINASE in FIELD MANUFACTURING, subject to
     Sections 7.4 and 7.5. Lastly, so long as COMPANY remains the exclusive
     licensee of PATENT RIGHTS ENZYMES in FIELD ENZYMES

<Page>

     excluding FIELD RESEARCH REAGENTS, COMPANY, to the extent permitted by law,
     shall have the right, under its own control and at its own expense, to
     prosecute any third party infringement of PATENT RIGHTS ENZYMES in FIELD
     ENZYMES excluding FIELD RESEARCH REAGENTS, subject to Sections 7.4 and 7.5.
     If required by law, M.I.T. shall permit any action under this Section to be
     brought in its name, including being joined as a party-plaintiff, provided
     that COMPANY shall hold M.I.T. harmless from, and indemnify M.I.T. against,
     any costs, expenses, or liability that M.I.T. incurs in connection with
     such action. Prior to commencing any such action, COMPANY shall consult
     with M.I.T. and shall consider the views of M.I.T. regarding the
     advisability of the proposed action and its effect on the public interest.
     COMPANY shall not enter into any settlement, consent judgment, or other
     voluntary final disposition of any infringement action under this Section
     without the prior written consent of M.I.T.

11.  Section 7.2(b) shall be modified to read:

     M.I.T. RIGHT TO PROSECUTE PATENT RIGHTS IN EXCLUSIVE FIELDS. In the event
     that COMPANY is unsuccessful in persuading the alleged infringer of PATENT
     RIGHTS HEPARIN in FIELD ALL BUT MACHINES, PATENT RIGHTS HEPARINASE in FIELD
     MANUFACTURING or PATENT RIGHTS ENZYMES in FIELD ENZYMES excluding FIELD
     RESEARCH REAGENTS to desist or fails to have initiated an infringement
     action within a reasonable time after COMPANY first becomes aware of the
     basis for such action, M.I.T. shall have the right, to prosecute such
     infringement under its sole control and at its sole expense, and any
     recovery obtained shall belong to M.I.T. If required by law, COMPANY hereby
     agrees that M.I.T. may include COMPANY as a party-plaintiff in any such
     suit, without expense to COMPANY. Prior to commencing any such action,
     M.I.T. shall consult with COMPANY and shall consider the views of COMPANY
     regarding the advisability of the proposed action. Further, M.I.T. shall
     not enter into any settlement, consent judgment, or other voluntary final
     disposition of any infringement action under this Section without first
     consulting with and considering the views of COMPANY. Notwithstanding the
     forgoing, any action taken under this Section shall be at the sole
     discretion of M.I.T.

12.  Section 7.2(c) shall be modified to read:

     M.I.T. RIGHT TO PROSECUTE PATENT RIGHTS IN NON-EXCLUSIVE FIELDS. M.I.T.
     shall have the right, but shall not be obligated, to prosecute at its sole
     control and sole expense all infringements of PATENT RIGHTS other than
     PATENT RIGHTS HEPARIN in FIELD ALL BUT MACHINES, PATENT RIGHTS HEPARINASE
     in FIELD MANUFACTURING or PATENT RIGHTS ENZYMES in FIELD ENZYMES excluding
     FIELD RESEARCH REAGENTS, and M.I.T. shall keep any recovery or damages
     derived there from, whether compensatory for past infringement or punitive.
     If required by law, COMPANY hereby agrees that M.I.T. may include COMPANY
     as a party plaintiff in any such suit, without expense to COMPANY. Prior to
     commencing any such action, M.I.T. shall consult with COMPANY and shall
     consider the views of COMPANY regarding the advisability of the proposed
     action. Further, M.I.T. shall not enter into any settlement, consent
     judgment, or other voluntary final disposition of any infringement action
     under this Section without first consulting with and considering the views
     of

<Page>

     COMPANY. Lastly, in the event that COMPANY approaches M.I.T. and requests
     that M.I.T. commence the prosecution of an infringement of any of the
     PATENT RIGHTS HEPARIN in FIELD ALL BUT MACHINES, the PATENT RIGHTS
     HEPARINASE in FIELD MANUFACTURING and the PATENT RIGHTS ENZYMES in FIELD
     ENZYMES excluding FIELD RESEARCH REAGENTS, M.I.T. agrees to give due
     consideration to the views of the COMPANY. Notwithstanding the forgoing,
     any action taken under this Section shall be at the sole discretion of
     M.I.T.

13.  Section 7.7 shall be modified to read:

     RIGHT TO SUBLICENSE. So long as COMPANY remains the exclusive licensee of
     the PATENT RIGHTS HEPARIN in FIELD ALL BUT MACHINES, PATENT RIGHTS
     HEPARINASE in FIELD MANUFACTURING or PATENT RIGHTS ENZYMES in FIELD ENZYMES
     excluding FIELD RESEARCH REAGENTS, COMPANY shall have the sole right to
     sublicense to any alleged infringer for future use of PATENT RIGHTS HEPARIN
     in FIELD ALL BUT MACHINES, PATENT RIGHTS HEPARINASE in FIELD MANUFACTURING
     or PATENT RIGHTS ENZYMES in FIELD ENZYMES excluding FIELD RESEARCH
     REAGENTS, as the case may be, in accordance with the terms and conditions
     of this Agreement relating to sublicenses. Any upfront fees as part of such
     sublicense shall [**]; other revenues to COMPANY pursuant to such
     sublicense shall be treated as set forth in Article 4.

All other terms and conditions of the License Agreement shall remain unchanged.

THE EFFECTIVE DATE OF THIS AMENDMENT IS NOVEMBER 15, 2002.

Agreed to for:
MASSACHUSETTS INSTITUTE OF                MOMENTA PHARMACEUTICALS, INC.
TECHNOLOGY

By: /s/ LITA NELSEN                       By: /s/ SUSAN K. WHORISKEY

Name: Lita L. Nelson                      Name: Susan K. Whoriskey, Ph. D.

Title: Director, Technology Licensing     Title: Vice President, Licensing &
       Office                                    Business Development

Date: December 20, 2002                   Date:
                                                --------------------------------

<Page>

                                   APPENDIX H

                              PATENT RIGHTS ENZYMES

M.I.T. CASE NO. [**]
Entitled: [**]

     United States of America [**]
     Entitled: [**]

M.I.T. CASE NO. [**]
Entitled: [**]
          [**]

M.I.T. CASE NO. [**]
Entitled: [**]
          [**]

<Page>

Momenta Pharmaceuticals, Inc.
43 Moulton Street
Cambridge, Massachusetts 02138

                                    September 12, 2003


Ms. Lita L. Nelsen, Director
Technology Licensing Office
Five Cambridge Center
Cambridge, Massachusetts 02142

Re:  Amended and Restated Exclusive Patent License
     ---------------------------------------------

Dear Ms. Nelsen:

Reference is made to the Amended and Restated Exclusive Patent License between
the Massachusetts Institute of Technology and Momenta Pharmaceuticals, Inc.
dated November 1, 2002 as amended on November 15, 2002 (the "Agreement").
Capitalized terms used herein and not otherwise defined shall have the meanings
given such terms in the Agreement.

As we have discussed, Momenta is engaged in negotiations that may lead to the
sublicense of the PATENT RIGHTS to a CORPORATE PARTNER and/or SUBLICENSEE for
the purpose of developing and commercializing an enoxaparin product (the
"PRODUCT"). In connection with such negotiations, Momenta desires certain
modifications of the Agreement. As M.I.T. is amenable to such modifications,
M.I.T. and Momenta agree as follows:

1.   In the event that (a) M.I.T. converts the exclusive rights granted to
COMPANY in Section 2.2 of the Agreement into non-exclusive rights in accordance
with Section 3.1 of the Agreement or (b) there is a termination of the Agreement
under Section 12.2 or 12.3 of the Agreement, notwithstanding any such conversion
or termination, M.I.T. agrees to honor the exclusive nature of the sublicense
granted by COMPANY to its CORPORATE PARTNER and/or SUBLICENSEE in connection
with the development and commercialization of the PRODUCT so long as (x) the
CORPORATE PARTNER and/or SUBLICENSEE is in compliance with its agreement with
COMPANY pertaining to the PRODUCT and (y) in the event of a termination of the
Agreement, the CORPORATE PARTNER and/or SUBLICENSEE agrees, in a writing
delivered to M.I.T., to fulfill COMPANY's financial and non-financial
commitments to M.I.T. with respect to the development and commercialization of
the PRODUCT.

For purposes of clarity, the financial commitments to M.I.T. shall include (a)
the obligation to pay to M.I.T. [**] percent ([**]%) of all of what would have
been CORPORATE PARTNER INCOME and SUBLICENSE INCOME to COMPANY and that would
otherwise have been due M.I.T. by COMPANY and (b) the obligation to pay to
M.I.T. royalties on NET SALES of LICENSED PRODUCTS that would have otherwise
have been due M.I.T., treating for such purpose the sales made by the CORPORATE
PARTNER and/or SUBLICENSEE as direct sales by COMPANY (i.e., the provisions of
Section 4.1(c) of the Agreement shall be applied as opposed to the provisions of
Section 4.1(d) of the Agreement). Lastly, the CORPORATE

<Page>

PARTNER and/or SUBLICENSEE shall assume COMPANY's reimbursement obligations to
M.I.T. with respect to patent costs.

For purposes of clarity, examples of non-financial commitments that would
pertain to the development and commercialization of the PRODUCT include those
relating to place of manufacture, method of payment, reporting and record
keeping, requirements relating to prosecution of infringers, indemnification and
insurance, and non-use of name.

2.   With respect to Section 2.4 of the Agreement, in the event that such
provision applies to the PRODUCT, if so requested by COMPANY, M.I.T. agrees to
use good faith efforts to assist COMPANY and its CORPORATE PARTNER and/or
SUBLICENSEE in applying for and attempting to obtain a waiver from the United
States government from the requirement that the PRODUCT be substantially
manufactured in the United States.

3.   M.I.T. agrees that COMPANY's CORPORATE PARTNER and/or SUBLICENSEE in
connection with the development and commercialization of the PRODUCT shall be a
third party beneficiary of the rights granted in this letter agreement to
COMPANY.

If the foregoing is in conformity with your understanding of our agreement,
please indicate your consent by countersigning the three copies of this letter
and by returning two to me.

                                          Very truly yours,


                                          /s/ SUSAN K. WHORISKEY

                                          Susan K. Whoriskey

                                          Vice President, Licensing and

                                          Business Development

Massachusetts Institute of Technology


By:    /s/ Lita Nelsen
    ----------------------------------
    Lita L. Nelsen, Director

<Page>

                          Momenta Pharmaceuticals, Inc.
                                43 Moulton Street
                         Cambridge, Massachusetts 02138

                                         October 22, 2003


Ms. Lita L. Nelsen, Director
Technology Licensing Office
Five Cambridge Center
Cambridge, Massachusetts 02142


Re:  Amended and Restated Exclusive Patent License
     ---------------------------------------------

Dear Ms. Nelsen:

Reference is made to the Amended and Restated Exclusive Patent License between
the Massachusetts Institute of Technology and Momenta Pharmaceuticals, Inc.
dated November 1, 2002 as amended on November 15, 2002 and by letter agreement
dated September 12, 2003 (the "Agreement"). Capitalized terms used herein and
not otherwise defined shall have the meanings given such terms in the Agreement.

As you are aware, Momenta is engaged in negotiations that may lead to the
sublicense of the PATENT RIGHTS to a CORPORATE PARTNER and/or SUBLICENSEE for
the purpose of developing and commercializing an enoxaparin product (the
"PRODUCT"). The purpose of this letter is to document our understanding of
COMPANY's obligations under Section 8.2 of the Agreement with respect to the
foregoing sublicense of the PATENT RIGHTS to Biochemie West Indies, N.V. and
Geneva Pharmaceuticals, Inc. (the "Sandoz Parties").

WITH RESPECT TO THE FOREGOING SUBLICENSE TO THE SANDOZ PARTIES, AS REQUIRED BY
THE AGREEMENT, COMPANY WILL BE OBLIGATED TO CARRY THE INSURANCE REQUIRED BY
SECTION 8.2 OF THE AGREEMENT.

COMPANY REPRESENTS THAT, UNDER THE TERMS OF ITS AGREEMENT WITH THE SANDOZ
PARTIES, THE SANDOZ PARTIES WILL PROVIDE CERTAIN INDEMNIFICATIONS TO COMPANY
WITH RESPECT TO CLAIMS AND DEMANDS RELATED TO THE PRODUCT THAT ARE BROUGHT BY A
THIRD PARTY AGAINST M.I.T. COMPANY FURTHER REPRESENTS THAT, WITH RESPECT TO
THESE INDEMNIFICATION OBLIGATIONS TO COMPANY, THE SANDOZ PARTIES WILL BE
SELF-INSURED.

COMPANY REPRESENTS THAT, UNDER THE TERMS OF THE AGREEMENT WITH THE SANDOZ
PARTIES, THE OBLIGATIONS OF BIOCHEMIE WEST INDIES, N.V. WILL BE GUARANTEED BY
GENEVA PHARMACEUTICALS, INC. AND/OR SANDOZ GMBH.

<Page>

COMPANY UNDERSTANDS THAT THE FACT THAT THE SANDOZ PARTIES WILL SELF-INSURE WITH
RESPECT TO THEIR INDEMNIFICATION OBLIGATIONS TO COMPANY IS ACCEPTABLE TO M.I.T.

If the foregoing is in conformity with your understanding, please indicate your
consent by countersigning the three copies of this letter and by returning two
to me. COMPANY and MIT agree that this letter will replace their letter dated
October 15, 2003.

                                          Very truly yours,

                                          /s/ Susan K. Whoriskey

                                          Susan K. Whoriskey
                                          Vice President, Licensing and
                                          Business Development

Massachusetts Institute of Technology


By:   /s/ Lita Nelson
   ----------------------------------
      Lita L. Nelson, Director

<Page>

                SECOND AMENDMENT TO THE NOVEMBER 1, 2002 LICENSE

     This Second Amendment, effective as of the date set forth above the
signatures of the parties below, pertains to the Amended and Restated Exclusive
Patent License Agreement, effective November 1, 2002, by and between the
Massachusetts Institute of Technology ("M.I.T.") and Momenta Pharmaceuticals,
Inc. ("COMPANY"), as subsequently amended by a First Amendment dated November
15, 2002 and letter agreements dated September 12, 2003 and October 22, 2003
(the "AGREEMENT"). Capitalized terms used herein and not otherwise defined shall
have the meanings given such terms in the AGREEMENT.

     WHEREAS, COMPANY has entered into an agreement with a CORPORATE PARTNER
and/or SUBLICENSEE which provides for a sublicense of the PATENT RIGHTS for the
purpose of developing and commercializing a generic form of enoxaparin for which
the filing of an ANDA is anticipated; and

     WHEREAS, M.I.T. is willing to treat the actual filing of such ANDA as
evidence of diligence under Section 3.1(h) of the AGREEMENT.

     NOW, THEREFORE, M.I.T. and COMPANY hereby agree to modify the AGREEMENT as
follows:

     1.   Section 3.1(h) shall be modified to read:

          "(h) COMPANY shall file, or cause its AFFILIATES, CORPORATE PARTNERS
          or SUBLICENSEES to file, [**]."

     2.   M.I.T. and COMPANY specifically acknowledge that they are not at this
          time considering any modifications of Section 3.1(i) of the AGREEMENT.
          Accordingly, the modification to Section 3.1(h) of the AGREEMENT shall
          have no implications, one way or the other, for Section 3.1(i) of the
          AGREEMENT.

     3.   All other terms and conditions of the License Agreement shall remain
          unchanged.

<Page>

THE EFFECTIVE DATE OF THIS AMENDMENT IS NOVEMBER 19, 2003.

Agreed to for:
MASSACHUSETTS INSTITUTE OF                MOMENTA PHARMACEUTICALS, INC.
TECHNOLOGY

By: /s/ LITA NELSEN                       By: /s/ SUSAN K. WHORISKEY

Name: Lita L. Nelson                      Name: Susan K. Whoriskey, Ph. D.

Title: Director, Technology Licensing     Title: Vice President, Licensing &
       Office                                    Business Development

Date: December 11, 2003                   Date:
                                                --------------------------------