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WHENEVER CONFIDENTIAL INFORMATION IS OMITTED HEREIN (SUCH OMISSIONS ARE DENOTED
BY AN ASTERISK*), SUCH CONFIDENTIAL INFORMATION HAS BEEN SUBMITTED SEPARATELY TO
THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO A REQUEST FOR CONFIDENTIAL
TREATMENT.

                                LICENSE AGREEMENT

     This Agreement is made and entered into this 9th day of September, 2003
(the "Effective Date") by and between Metabolix, Inc., a corporation duly
organized and existing under the laws of the State of Delaware and having its
principal office at 303 Third Street, Cambridge, Massachusetts 02142
(hereinafter referred to as "Metabolix"), and Tepha, Inc., a corporation duly
organized and existing under the laws of the State of Delaware and having its
principal office at 303 Third Street, Cambridge, Massachusetts 02142
(hereinafter referred to as "Tepha").

     WHEREAS, Metabolix is the assignee from Monsanto Company ("Monsanto") of
all right, title and interest in the Patent Rights, Biological Materials and
Know-How (all as defined herein);

     WHEREAS, Metabolix wishes to grant, and Tepha wishes to receive, license
rights to the Patent Rights, Biological Materials and Know-How; and

     WHEREAS, the grant of such license rights is subject to the prior written
approval of Monsanto, which has been obtained, and a copy of which is attached
as Appendix D for reference only.

     NOW THEREFORE, in consideration of the premises and the mutual covenants
contained herein, the parties hereto agree as follows:

1.   DEFINITIONS.

     1.1.  "Patent Rights" shall mean: (i) the U.S. and foreign patent
           applications and patents set forth in Appendix A, and the inventions
           described and/or claimed therein, and all other patent rights
           assigned to Metabolix by Monsanto not relating to plant crop
           production of PHAs shall be added to Appendix A by amendment; (ii)
           any divisionals, continuations and continuation-in-part applications
           which shall be directed to subject matter specifically described in
           such patent applications; (iii) the resulting U.S. and foreign
           patents; (iv) any reissues, reexaminations or extensions of such
           patents; and (v) all foreign counterparts of the above patent
           applications and patents. For the avoidance of doubt, the Patent
           Rights do not include any of the Zeneca Limited patent rights
           licensed to Metabolix by Monsanto in the Patent Sub-License Agreement
           dated May 14, 2001.

     1.2.  "Biological Materials" shall mean the biological materials set forth
           in Appendix B, and all Progeny and Unmodified Derivatives of those
           materials, but excluding Modifications. "Progeny" shall mean an
           unmodified descendant from the Biological Materials, such as virus
           from virus, cell from cell, or organism from organism. "Unmodified
           Derivatives" shall mean substances created by Tepha which constitute
           an unmodified functional subunit or product expressed by the
           Biological Material(s), (some examples include: subclones of
           unmodified cell

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           lines, purified or fractionated subsets of the Biological
           Material(s), proteins expressed by DNA/RNA supplied by Metabolix, or
           monoclonal antibodies secreted by a hybridoma cell line).

     1.3.  "Modifications" shall mean substances created by Tepha that
           contain/incorporate Biological Material(s).

     1.4.  "Know-How" shall mean the know-how set forth in Appendix C.

     1.5.  "Field" shall mean IN VIVO human and veterinary medical use of
           polymers falling within the Patent Rights, including, without
           limitation, tissue engineering, cell therapy, implantables, medical
           devices, wound sealants, prescription and non-prescription drug
           delivery, and contrast agents, but excluding (i) medical disposables,
           surgical drapes and trays, sanitary products, barrier contraceptives,
           nutritional and all other diagnostic uses and (ii) transgenic plant
           crop production of polymers. For the purpose of clarity, it is agreed
           and understood that, notwithstanding anything in the prior sentence
           to the contrary, diagnostic systems and/or devices used to monitor
           the IN VIVO use of a Licensed Product shall be included within the
           Field. For the purpose of determining whether a use falls within the
           Field, the parties shall apply the following guidelines: (x)
           regulation of a use by the U.S. Food and Drug Administration or other
           regulatory body shall be indicative but not presumptive that a use is
           an IN VIVO use, and (y) uses marketed only to physicians shall
           primarily fall within the Field, and (z) uses marketed directly only
           to consumers shall primarily fall outside the Field.

     1.6.  "Net Sales shall mean Tepha's billings for the use, sale, lease or
           other disposition of Licensed Products and Licensed Processes, and
           the fair market value of noncash consideration, less:

           1.6.1  discounts allowed in amounts customary in the trade;

           1.6.2  sales, tariff duties and/or use taxes directly imposed and
                  with reference to particular sales;

           1.6.3  outbound transportation prepaid or allowed; and

           1.6.4  amounts allowed or credited on returns.

     No deduction shall be made for commissions paid to individuals whether they
     be with independent sales agencies or regularly employed by Licensee and on
     its payroll, or for cost of collections. Licensed Products shall be
     considered "sold" when invoiced. "Net Sales" shall not include Licensed
     Products sold for clinical testing, research or development. If a Licensed
     Product or Licensed Process shall otherwise be distributed or invoiced for
     a discounted price substantially lower than customary in the trade or
     distributed at no cost to Tepha Affiliates or otherwise, Net Sales shall be
     based on the customary amount billed for such Licensed Products or Licensed
     Processes.

     Where the Licensed Product is a combination product consisting of material
     whose composition or manufacture is covered by the Patent Rights ("Patented
     Material") plus other materials (such as a growth factor, but not, for
     example, filler materials) that are not

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     covered by the Patent Rights, then "Net Sales" shall mean the Net Sales of
     the full product multiplied by the fully loaded manufacturing cost of the
     Patented Material divided by the total fully loaded manufacturing cost of
     the total combination product. When the Licensed Product consists of a
     combination product consisting of a component made from the Patented
     Material plus other components, then "Net Sales" shall mean Net Sales of
     the total product multiplied by the fully loaded manufacturing cost of the
     Patented Material component divided by the fully loaded manufacturing cost
     of the total product. By "fully loaded" is meant the cost of goods sold
     plus overhead allocated to production and sale thereof.

     1.7.  "Tepha" and "Metabolix" shall include "Affiliates." "Affiliates"
           shall mean a related company of Tepha or Metabolix, respectively, the
           voting stock of which is directly or indirectly at least fifty
           percent (50%) owned and controlled by Tepha or Metabolix, an
           organization which directly or indirectly controls more than fifty
           percent (50%) of the voting stock of Tepha or Metabolix, and an
           organization the majority ownership of which is directly or
           indirectly common to the ownership of Tepha or Metabolix.

     1.8.  "Licensed Process" means any process which is covered in whole or in
           part by an issued, unexpired valid claim or a pending claim contained
           in the Patent Rights in the country in which such process is used or
           in which the Licensed Product made thereby is used or sold.

     1.9.  "Licensed Product" means any product or part thereof which: (i) is
           covered in whole or in part by an issued, unexpired valid claim or a
           pending claim contained in the Patent Rights in the country in which
           any such product or part thereof is made, used or sold; or (ii) is
           manufactured by using a process or is employed to practice a process
           which is covered in whole or in part by an issued unexpired valid
           claim or a pending claim contained in the Patent Rights in the
           country in which a Licensed Process is used or in which such product
           or part thereof is used or sold.

2.   LICENSE GRANT AND OWNERSHIP

     2.1.  NONEXCLUSIVE LICENSE. Subject to the terms and conditions of this
           Agreement, Metabolix hereby grants to Tepha the worldwide,
           nonexclusive right and license, with the right to sublicense, in the
           Field: (i) under the Patent Rights to make, have made, use, lease,
           sell, offer for sale and import the Licensed Products and to practice
           the Licensed Processes until the expiration of the last to expire of
           the Patent Rights, unless this Agreement shall be sooner terminated
           according to the terms hereof; (ii) to make, have made, use, lease,
           sell, offer for sale, import and create Modifications of the
           Biological Materials; and (iii) to use Know-How.

     2.2.  EXCLUSIVE LICENSE. Subject to the terms and conditions of this
           Agreement, Metabolix hereby grants to Tepha the worldwide,
           royalty-free, exclusive right and license, with the right to
           sublicense, in the Field to make, have made, use, lease, sell, offer
           for sale and import Modifications.

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     2.3.  DELIVERY. Tepha shall have thirty (30) days after the Effective Date
           to review and make copies of the Know-How and Biological Materials.
           Metabolix makes no representations regarding the viability of any of
           the Biological Materials. After thirty (30) days from the Effective
           Date, any request to review or make copies of the Know-How or
           Biological Materials shall be at Metabolix's discretion.

     2.4.  OWNERSHIP OF MODIFICATIONS. Tepha hereby assigns to Metabolix all of
           its right, title and interest in and to the Modifications, including
           any and all intellectual property rights therein. Tepha also agrees
           to promptly execute all assignments and patent applications, and
           similar documents as reasonably requested by Metabolix. If Metabolix
           shall be unable to obtain Tepha's execution of such documents for any
           reason, Tepha hereby irrevocably appoints Metabolix and its agents as
           Tepha's agents and attorneys-in-fact to execute such documents with
           the same legal effect as if Tepha shall have executed them.

     2.5.  RIGHT TO SUBLICENSE. Tepha's right to sublicense in Paragraphs 2.1
           and 2.2 is subject to Metabolix' prior written approval during the
           period that Metabolix requires Monsanto's approval to sublicense.
           Tepha agrees to insert a provision in each sublicense that Metabolix
           is a third party beneficiary of the sublicense as to the sublicensed
           Patent Rights, with the right to enforce the applicable terms thereof
           in the event Tepha does not enforce its rights.

     2.6.  NO OTHER RIGHTS. Nothing in this Agreement shall be construed to
           confer any rights upon Tepha by implication, estoppel or otherwise
           beyond the express licenses granted by Metabolix or as to any
           technology or patent rights of Metabolix or any other entity other
           than the Patent Rights, Biological Materials and Know-How.

     2.7.  MONSANTO RIGHTS. Monsanto retains certain rights to Patent Rights as
           collateral in the event of default by Metabolix under a Security
           Agreement between Monsanto and Metabolix dated May 12, 2001, and this
           Agreement is subject to Monsanto's rights therein. Monsanto has
           granted its approval of this Agreement in the letter attached as
           Appendix D; however, Monsanto retains all of its rights during the
           remaining term of the Security Agreement, including without
           limitation its rights to Patent Rights as collateral, and in the
           event Tepha exercises its right to sublicense third parties, such
           sublicenses shall also be subject to such Monsanto's rights.

3.   ROYALTIES

     3.1.  LICENSE ISSUE FEE. In partial consideration for the license rights
           granted herein, Tepha shall pay Metabolix a License Issue Fee of *
           which shall be deemed earned and due as follows: * on the Effective
           Date, and * on each of the six-month, twelve-month and
           eighteenth-month anniversaries of the Effective Date; provided,
           however, the balance of the full amount of such License Issue Fee
           shall be due upon the raising by Tepha of * (cumulatively) after the
           Effective Date in investment capital and/or research and development
           funds in connection with the

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           Patent Rights, Biological Materials and Know-How, and payment shall
           be made within thirty (30) days thereafter.

     3.2   RUNNING ROYALTIES. In partial consideration for the license rights
           granted herein, Tepha shall pay Metabolix running royalties of * of
           Net Sales by Tepha ("Running Royalty"); provided, however, the
           maximum cumulative Running Royalties due on particular Net Sales of
           any Licensed Product or Licensed Process payable by Tepha to
           Metabolix for any quarter under (i) this Agreement, and (ii) the
           sublicense from Metabolix to Tepha to certain Massachusetts Institute
           of Technology patent rights dated October 1, 1999, as amended, shall
           be * of such Net Sales, subject to any deductions permitted under
           Paragraph 3.7.

     3.3   SUBLICENSE REVENUE. Tepha shall pay Metabolix a * share of gross
           sublicensing revenue, including sublicense issue fees, milestone
           payments, license maintenance fees, royalties on net sales, and
           similar consideration, and including, for the avoidance of doubt, the
           fair market value of any sublicense rights granted in a multi-part
           transaction, but excluding research and development funding received
           by Tepha; provided, however, the maximum cumulative share of gross
           sublicensing revenue in regard to a particular sublicense payable by
           Tepha to Metabolix for any quarter under (i) this Agreement, and (ii)
           the sublicense from Metabolix to Tepha to certain Massachusetts
           Institute of Technology patent rights dated October 1, 1999, as
           amended, shall be * of such gross sublicensing revenue. For purposes
           herein, sublicensees' net sales shall have a parallel meaning to the
           definition of Tepha's Net Sales in Paragraph 1.6.

     3.4   PAYMENTS IN FULL. All payments due hereunder shall be paid in full,
           without deduction of taxes or other fees which may be imposed by any
           government, except as otherwise provided in Paragraph 1.6.2.

     3.5   NO MULTIPLE ROYALTIES. No multiple Running Royalties shall be payable
           because any Licensed Product or Licensed Process, its manufacture,
           use, sale or importation are or shall be covered by more than one
           patent application or patent licensed under this Agreement.

     3.6   PAYMENT. Royalty payments shall be paid in the United States dollars
           in Cambridge, Massachusetts, or at such other place as Metabolix may
           reasonably designate consistent with the laws and regulations
           controlling in any foreign country. If any currency conversion shall
           be required in connection with the payment of royalties hereunder,
           such conversion shall be made by using the exchange rate published in
           the Wall Street Journal on the last business day of the calendar
           quarterly reporting period to which such royalty payments relate.

     3.7   THIRD PARTY LICENSES. To the extent that Tepha has executed or shall
           obtain subsequent to the Effective Date licenses to third party
           patents or other intellectual property that are necessary to
           manufacture or sell Licensed Products or Licensed Processes in the
           Field, Tepha may deduct from the Running Royalty due to Metabolix
           under Paragraph 3.2, * of the running royalties due on such third

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           party patents or intellectual property up to an amount equal to * of
           the Running Royalties due hereunder.

     3.8   APPLICATION OF CREDITS. Any credits against Running Royalties
           permitted under this Agreement may be applied by Tepha, cumulatively,
           up to * the Running Royalties otherwise due in the respective
           quarterly accounting period; provided, Tepha may carry over unused
           credits to subsequent quarterly accounting periods. Notwithstanding
           the applicability of credits under one or more Paragraphs of this
           Agreement, the minimum Running Royalties due from Tepha shall be * of
           the Running Royalties otherwise payable, subject to the maximum set
           forth in Paragraph 3.2.

4.   PATENT PROSECUTION

     4.1.  PATENT PROSECUTION. Throughout the term of this Agreement, Metabolix,
           at its own expense, shall file, prosecute and maintain the Patent
           Rights. If Metabolix shall elect not to file, prosecute or maintain
           any Patent Right, Metabolix shall notify Tepha in writing with at
           least thirty (30) days notice prior to any filing, action, payment or
           the like being due, in which event Tepha shall have the right to
           file, prosecute or maintain such Patent Right, at Tepha's expense in
           Metabolix' name. Metabolix agrees to execute, and agrees to use
           reasonable efforts to ensure that its employees shall execute, all
           documents necessary to perfect filing, advance prosecution and/or
           effect issue of any patents upon any such applications. After notice
           of such election by Metabolix, Tepha shall have no further royalty
           obligations under Paragraphs 3.2 and 3.3 with respect to such patents
           or applications.

5.   RECORDS AND PAYMENTS

     5.1.  RECORDS AND AUDIT. Tepha shall keep true and accurate books of
           account containing all particulars that may be necessary for the
           purpose of showing the amounts payable to Metabolix hereunder. Said
           books of account shall be kept at Tepha's principal place of business
           and shall be open at all reasonable times for three (3) years
           following the end of the calendar year to which they pertain, to the
           inspection of Metabolix or its agents for the purpose of verifying
           Tepha's royalty statements or compliance in other respect with this
           Agreement. Should such inspection lead to the discovery of a greater
           than Ten Percent (10%) discrepancy in reporting to Metabolix's
           detriment, Tepha agrees to pay the cost of such inspection.

     5.2.  REPORTS AND PAYMENTS. Within thirty (30) days after the end of each
           calendar quarter during the term of this Agreement, Tepha shall send
           to Metabolix a report showing the Net Sales of the Licensed Products
           and Licensed Processes, including calculation of deductions, and
           sublicensing gross revenue for such quarter and shall pay the
           appropriate royalties to Metabolix.

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     5.3.  INTEREST. The amounts due under Articles 3 shall, if overdue, bear
           interest until payment at a per annum rate * above * in effect at
           Fleet Bank, or its successors, on the due date. The payment of such
           interest shall not foreclose Metabolix from exercising any other
           rights it may have as a consequence of the lateness of any payment.

6.   DUE DILIGENCE

     6.1.  DILIGENT EFFORTS. Tepha shall use diligent efforts to bring one or
           more Licensed Products or Licensed Processes to market through a
           thorough, vigorous and diligent program for exploitation of the
           Patent Rights and shall continue active, diligent development and
           marketing efforts for one or more Licensed Products or Licensed
           Processes throughout the term of this Agreement

     6.2.  GOVERNMENTAL APPROVALS AND MARKETING OF LICENSED PRODUCTS. Tepha or
           its designees shall be responsible for obtaining all necessary
           governmental approvals for the development, production, distribution,
           sale and use of any Licensed Product, at Tepha's, or its designees',
           expense, including, without limitation, any safety studies. Tepha or
           its designees shall have sole responsibility for any warning labels,
           packaging and instructions as to the use of Licensed Products and for
           the quality control for any Licensed Product.

7.   INFRINGEMENT

     7.1.  NOTICE. Tepha and Metabolix shall each inform the other promptly in
           writing of any alleged or threatened infringement of the Patent
           Rights by a third party and of any available evidence thereof.

     7.2.  PURSUIT OF INFRINGERS. During the term of this Agreement, Tepha shall
           have the right, but shall not be obligated, to prosecute at its own
           expense all infringements of the Patent Rights by a third party in
           the Field by litigation or settlement discussions and, in furtherance
           of such right, Metabolix agrees that Tepha may join Metabolix as a
           party plaintiff in any such suit, without expense to Metabolix. The
           total cost of any such infringement action commenced solely by Tepha
           shall be borne by Tepha. In the event that Tepha shall have exercised
           its right to bring an action, Tepha shall be responsible for
           defending against any counterclaims alleging invalidity or
           unenforceability of a Patent Right and for prosecuting the action
           through to settlement or other final disposition. In the event that
           Tepha shall undertake the enforcement of the Patent Rights in the
           Field by litigation, Tepha may withhold up to * of the Running
           Royalties otherwise thereafter due to Metabolix under Paragraph 3.2
           and apply the same toward reimbursement of up to * of Tepha's
           expenses, including reasonable attorneys' fees, in connection
           therewith.

     7.3.  If within six (6) months after having been notified of any alleged
           infringement, Tepha shall have been unsuccessful in persuading the
           alleged infringer to desist and shall not have brought and shall not
           be diligently prosecuting an infringement

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           action, or if Tepha shall notify Metabolix at any time prior thereto
           of its intention not to bring suit against any alleged infringer,
           then, and in those events, only, Metabolix shall have the right, but
           shall not be obligated, to prosecute at its own expense any
           infringement of the Patent Rights in the Field. In furtherance of
           such right, Tepha hereby agrees that Metabolix may include Tepha as a
           party plaintiff in any such suit, without expense to Tepha. The total
           cost of any such infringement action commenced or defended solely by
           Metabolix shall be borne by Metabolix, and Metabolix shall be
           responsible for defending against any counterclaims alleging
           invalidity or unenforceability of a Patent Right.

     7.4.  Any recovery of damages by the prosecuting party for any such suit
           shall be applied first in satisfaction of any unreimbursed expenses
           and legal fees of such party relating to the suit, and next toward
           reimbursement of Metabolix for any royalties past due or withheld and
           applied pursuant to Paragraph 7.2, if applicable. The balance
           remaining from any such recovery shall be divided with * to the
           non-prosecuting party and any remaining balance to the prosecuting
           party.

     7.5.  In the event of the institution of any suit by a third party against
           Metabolix, Tepha or its sublicensees for patent infringement
           involving the Patent Rights in the Field, the party sued shall
           promptly notify the other party in writing. Tepha shall have the
           right, but not the obligation, to defend such suit at its own
           expense. If Tepha shall elect not to defend, Tepha shall promptly
           notify Metabolix. Metabolix shall have the right, but not the
           obligation, to defend such suit at its expense.

     7.6.  If Tepha shall exercise its rights pursuant to Section 7.5 to defend
           the Patent Rights, then * of Tepha's Running Royalty obligation in
           Paragraph 3.2 during the pendency of defense in the proceeding shall
           be held in an interest-bearing escrow account by Tepha until a final
           decision shall be rendered by a court or administrative tribunal of
           competent jurisdiction from which no appeal can be or is taken
           provided that:

           7.6.1  If the enforceability of all material claims in such Patent
                  Right claiming the Licensed Product or Licensed Process is
                  upheld by a court of other legal or administrative tribunal
                  from which no appeal is or can be taken, then the amount of
                  Running Royalties withheld during the period of escrow, plus
                  all accrued interest, shall be promptly paid to Metabolix; or

           7.6.2  If one or more claims in such Patent Right covering the
                  Licensed Product or Licensed Process shall be held to be
                  invalid or otherwise unenforceable by a court or other legal
                  or administrative tribunal in any country from which no appeal
                  is or can be taken or the scope thereof is modified and, as a
                  result such Patent Right no longer offers substantial
                  protection to a Licensed Product or Licensed Process in such
                  country, then the amount of Running Royalties withheld during
                  the period of escrow shall not be owed to Metabolix; Tepha
                  shall be entitled to all payments and accrued interest in the
                  escrow account; and the Running Royalties otherwise payable
                  shall

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                  be abated in their entirety with respect to Net Sales of
                  Licensed Products or Licensed Processes covered only by such
                  Patent Right in the country in which such claims were so held
                  invalid or unenforceable or so modified.

     7.7.  In any suit as either party may institute to enforce or defend the
           Patent Rights pursuant to this Agreement, the other party hereto
           shall, at the request and expense of the party initiating such suit,
           cooperate in all respects and, to the extent possible, have its
           employees testify when requested and make available relevant records,
           papers, information, samples, specimens and the like. The parties
           shall keep one another informed of the status of and of their
           respective activities regarding any litigation or settlement thereof
           concerning the Patent Rights in the Field or Licensed Products or
           Licensed Processes; provided, however, that no settlement or consent
           judgement or other voluntary final disposition of any suit defended
           or action brought by a party pursuant to this Article 7 may be
           entered into without the consent of the other party, such consent not
           to be unreasonably withheld or delayed.

     7.8.  Tepha, during the period of this Agreement, shall have the sole right
           in accordance with the terms and conditions herein to sublicense any
           alleged infringer for future use of the Patent Rights in the Field.

8.   PRODUCT LIABILITY

     8.1.  INDEMNIFICATION. Tepha shall at all times during the term of this
           Agreement and thereafter, indemnify, defend and hold Metabolix and
           Monsanto, their directors, officers, employees and Affiliates,
           harmless against all claims and expenses, arising out of the death of
           or injury to any person or persons or out of any damage to property
           and against any other claim, proceeding, demand, expense and
           liability of any kind whatsoever resulting from or relating to the
           production, manufacture, sale, use, lease, consumption or
           advertisement of the Licensed Products and/or Licensed Process(es) *.

     8.2.  INSURANCE. Prior to the first use of a Licensed Product for humans,
           Tepha shall obtain and carry in full force and effect commercial,
           general liability insurance, including product liability insurance,
           which shall protect Tepha, Metabolix and Monsanto with respect to
           events covered by Paragraph 8.1 above. Such insurance shall be
           written by a reputable insurance company authorized to do business in
           the Commonwealth of Massachusetts, shall list Metabolix and Monsanto
           as additional named insured thereunder, shall be endorsed to include
           product liability coverage and shall require thirty (30) days written
           notice to be given to Metabolix prior to any cancellation or material
           change thereof. The limits of such insurance shall not be less than *
           per occurrence with an aggregate of * for personal injury including
           death; and * per occurrence with an aggregate of * for property
           damage. Tepha shall provide Metabolix with Certificates of Insurance
           evidencing the same. Tepha shall maintain such commercial general
           liability insurance during the period that any Licensed Product or
           Licensed Process is being used, distributed or sold and for six (6)
           years thereafter.

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9.   WARRANTIES AND DISCLAIMER

     9.1.  Metabolix warranty. Metabolix represents and warrants to Tepha that
           Metabolix *.

     9.2.  DISCLAIMER. EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT: NEITHER
           PARTY, NOR THEIR RESPECTIVE DIRECTORS, OFFICERS, EMPLOYEES AND
           AFFILIATES MAKE ANY REPRESENTATIONS OR EXTEND ANY WARRANTIES OF ANY
           KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
           WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
           VALIDITY OF PATENT RIGHTS CLAIMS, ISSUED OR PENDING, AND THE ABSENCE
           OF LATENT OR OTHER DEFECTS, WHETHER OR NOT DISCOVERABLE. NOTHING IN
           THIS AGREEMENT SHALL BE CONSTRUED AS A REPRESENTATION MADE OR
           WARRANTY GIVEN BY EITHER PARTY OR BY MONSANTO THAT THE PRACTICE OF
           THE LICENSES GRANTED HEREUNDER SHALL NOT INFRINGE THE PATENT RIGHTS
           OR OTHER INTELLECTUAL OR PROPRIETARY RIGHTS OF ANY THIRD PARTY.

10.  LIMITATION OF LIABILITY

     10.1. NO CONSEQUENTIAL DAMAGES. *, IN NO EVENT SHALL METABOLIX, TEPHA, OR
           THEIR RESPECTIVE DIRECTORS, OFFICERS, EMPLOYEES AND AFFILIATES BE
           LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, INCLUDING
           ECONOMIC DAMAGE OR 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.

11.  EXPORT CONTROLS

     11.1. Tepha acknowledges that it is subject to United States laws and
           regulations controlling the export of technical data, computer
           software, laboratory prototypes and other commodities (including the
           Arms Export Control Act, as amended and the United States Department
           of Commerce Export Administration Regulations). The transfer of such
           items may require a license from the cognizant agency of the United
           States Government and/or written assurances by Tepha that Tepha shall
           not export data or commodities to certain foreign countries without
           prior approval of such agency. Metabolix neither represents that a
           license shall not be required nor that, if required, it shall be
           issued.

12.  NON-USE OF NAMES

     12.1. Except as required by law or in raising funding, neither party shall
           use the names or trademarks of the other, nor any adaptation thereof,
           nor the names of any of the

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           other party's employees, in any advertising, promotional or sales
           literature without prior written consent obtained from such party, or
           said employee, in each case, such consent not to be unreasonably
           withheld, except that Tepha may state that it is licensed by
           Metabolix, under one or more of the patents and/or applications
           comprising the Patent Rights. Tepha may, however, use the name of any
           employee of Metabolix who is a consultant or member of an advisory
           board of Tepha, with their permission, and provided, also, that their
           affiliation with Metabolix is identified.

13.  DISPUTE RESOLUTION

     13.1. Except for the right of either party to apply to a court of competent
           jurisdiction for a temporary restraining order, a preliminary
           injunction or other equitable relief to preserve the status quo or to
           prevent irreparable harm, and except for any dispute relating to
           patent validity or infringement, any and all claims, disputes or
           controversies arising under, out of or in connection with the
           Agreement, shall be mediated in good faith. The party raising such
           dispute shall promptly advise the other party of such claim, dispute
           or controversy in a writing which describes in reasonable detail the
           nature of such dispute. If the parties by their senior management
           representatives shall be unable to resolve the dispute within thirty
           (30) days, then by no later than forty (40) business days after the
           recipient has received such notice of dispute, each party shall have
           selected for itself a representative who shall have the authority to
           bind such party, and shall additionally have advised the other party
           in writing of the name and title of such representative. By no later
           than sixty (60) business days after the date of such notice of
           dispute, such representatives shall schedule a date for a mediation
           hearing with the Cambridge Dispute Settlement Center or Endispute
           Inc. in Cambridge, Massachusetts or another mutually agreeable
           mediator. The parties shall enter into good faith mediation and shall
           share the costs equally. If the representatives of the parties have
           not been able to resolve the dispute within thirty (30) business days
           after such mediation hearing, the parties shall have the right to
           pursue any other remedies legally available to resolve such dispute
           in either the Courts of the Commonwealth of Massachusetts, or in the
           United States District Court for the District of Massachusetts, to
           whose jurisdiction for such purposes Metabolix and Tepha each hereby
           irrevocably consents and submits.

     13.2. Notwithstanding the foregoing, nothing in this Article shall be
           construed to waive any rights or timely performance of any
           obligations under this Agreement.

14.  CONFIDENTIALITY

     14.1. CONFIDENTIAL INFORMATION. Both Metabolix and TEPHA agree that all
           confidential information disclosed to the other party shall be deemed
           "Confidential Information" of the disclosing party. In particular,
           "Confidential Information" shall be deemed to include, but not be
           limited to, Know-How, Biological Materials, trade secrets,
           information, ideas, inventions, materials, samples, processes,
           procedures, methods, formulations, protocols, packaging designs and

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           materials, test data, future development plans, "Product" launch
           date, technological know-how and engineering, manufacturing,
           regulatory, marketing, servicing, sales, or financial matters
           relating to the disclosing party and its business.

     14.2. NONDISCLOSURE AND NONUSE. During the term and thereafter each
           receiving party: (i) shall maintain all Confidential Information in
           confidence; (ii) shall not disclose any Confidential Information to
           any third party without prior written consent of the disclosing party
           except that the receiving party may disclose in connection with
           consultants, subcontractors or agents or raising funding and
           technical development activities for purposes consistent with this
           Agreement pursuant to a written non-disclosure agreement with said
           parties, having terms of nondisclosure and nonuse at least as
           restrictive as those set forth herein; and (iii) shall use such
           Confidential Information only to the extent required to accomplish
           the purposes of this Agreement. A receiving party may disclose
           Confidential Information that is required to be disclosed pursuant to
           the law, by request of the FDA or other government authority or for
           medical or safety reasons, but only to the extent required to be
           disclosed by the FDA or other government authority. Both parties
           shall take precautions as each normally takes with its own
           confidential and proprietary information to prevent disclosure to
           third parties, but no less than reasonable precautions.

     14.3. EXCEPTIONS. Both parties agree that, notwithstanding the above, the
           obligations of confidentiality and nonuse shall not apply to:

           14.3.1 Information that at the time of disclosure is, or thereafter
                  becomes, generally known to the public, through no wrongful
                  act or failure to act on the part of the receiving party;

           14.3.2 Information that was known by or in the possession of the
                  receiving party at the time of receiving such information from
                  the disclosing party, as evidenced by written records;

           14.3.3 Information obtained by the receiving party from a third party
                  who is not breaching a commitment of confidentiality to the
                  disclosing party by revealing such information to the
                  receiving party, as evidenced by written records; or

           14.3.4 Information that is developed independently by the receiving
                  party without use of confidential information of the other
                  party, as evidenced by written records.

     14.4. Both Parties shall make diligent efforts to ensure that all
           employees, consultants, agents and subcontractors who may have access
           to Confidential Information of the other party, and any other third
           parties who might have access to Confidential Information, shall sign
           nondisclosure agreements consistent with the terms set forth in this
           Paragraph. No Confidential Information shall be disclosed to any
           employees, subcontractors, agents, consultants or third parties who
           do not have a need to receive such information for the purposes of
           this Agreement.

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15.  TERMINATION

     15.1. TERMINATION BY METABOLIX. If Tepha shall cease to carry on its
           business, this Agreement shall terminate effective upon notice by
           Metabolix.

     15.2. TERMINATION FOR NONPAYMENT. Should Tepha fail to make any payment
           whatsoever due and payable to Metabolix hereunder, Metabolix shall
           have the right to terminate this Agreement effective on sixty (60)
           days' notice, unless Tepha shall make all such payments to Metabolix,
           within said sixty (60) day period. Upon the expiration of the sixty
           (60) day period, if Tepha shall not have made all such payments to
           Metabolix, the rights, privileges and license granted hereunder shall
           automatically terminate.

     15.3. TERMINATION FOR MATERIAL BREACH. Upon any material breach or default
           of this Agreement by Tepha, other than those occurrences set out in
           Paragraphs 15.1 and 15.2 hereinabove, which shall always take
           precedence in that order over any material breach or default referred
           to in this Paragraph 15.3, Metabolix shall have the right to
           terminate this Agreement and the rights, privileges and license
           granted hereunder effective on one hundred and twenty (120) days'
           notice to Tepha. Such termination shall become automatically
           effective unless Tepha shall have cured any such material breach or
           default prior to the expiration of the one hundred and twenty (120)
           day period. Upon any material breach or default of this Agreement by
           Metabolix, Tepha shall have the right to terminate this Agreement and
           the rights, privileges and license granted hereunder effective on one
           hundred and twenty (120) days' notice to Metabolix. Such termination
           shall become automatically effective unless Metabolix shall have
           cured any such material breach or default prior to the expiration of
           the one hundred and twenty (120) day period.

     15.4. TERMINATION BY TEPHA. Tepha shall have the right to terminate this
           Agreement at any time on six (6) months' notice to Metabolix, and
           upon payment of all amounts due Metabolix through the effective date
           of termination.

     15.5. DEFINITION OF EXPIRATION. For purposes of this Agreement, the term
           "expiration" shall mean expiration of the last to expire of the
           Patent Rights, and the co-terminus expiration of this Agreement,
           subject to the surviving licenses and provisions. The term
           "termination" shall mean termination of this Agreement prior to
           expiration in accordance with this Article 15.

     15.6. EFFECTS OF TERMINATION. Upon expiration or termination of this
           Agreement for any reason: (i) nothing herein shall be construed to
           release either party from any obligation that matured prior to
           expiration or the effective date of termination; (ii) Articles 1,
           2.4, 5.1 (for three (3) years), 7.1 (as to any infringement action
           instituted prior to termination), 8, 10, 13, 14, 16.4, 16.5, 16.6 and
           17 shall survive expiration or any termination; (iii) for a period of
           six (6) months after the effective date of termination, Tepha and its
           sublicensees may sell Licensed Products in inventory, and complete
           Licensed Products in the process of

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           manufacture at the time of such termination and sell the same,
           provided that Tepha shall pay the Running Royalties thereon as
           required by Article 3 of this Agreement and shall submit the reports
           required by Article 5 hereof on the sales of Licensed Products; (iv)
           if requested, each party shall immediately return all Confidential
           Information to the disclosing party and shall cease and refrain from
           any further use of such Confidential Information; (v) upon
           termination of this Agreement for any reason, any sublicense not then
           in default shall continue in full force and effect except that
           Metabolix shall be substituted in place of the Tepha, and Metabolix
           shall have no obligations under such sublicense beyond their
           obligations herein; (vi) upon termination (as defined in Paragraph
           15.5), if requested by Metabolix, Tepha shall return all Biological
           Materials and Know-How; and (vii) after expiration of this Agreement
           (as defined in Paragraph15.5), Tepha shall retain a perpetual,
           irrevocable, royalty-free, non-exclusive, transferable, worldwide
           license in the Field, with the right to sublicense, to use the
           Know-How.

     15.7. LICENSE TO METABOLIX. Upon termination of this Agreement for any
           reason (except expiration or termination by Tepha for breach by
           Metabolix under Paragraph 15.3), Tepha shall, grant and hereby grants
           Metabolix a nonexclusive license, with the right to sublicense, to
           all information then in Tepha's possession relevant to the
           commercialization of Licensed Products and/or Licensed Processes,
           including, but not limited to, research results, toxicology data,
           assays, preclinical data, prototypes, manufacturing processes
           including cell lines and unused, unexpired amounts of Licensed
           Products, clinical results, regulatory submissions, suppliers and
           customer lists. In such event Tepha shall receive a royalty equal to
           * of the gross amount of consideration, if any, subsequently received
           by Metabolix with respect to the Licensed Products and Licensed
           Processes.

16.  GENERAL

     16.1. INTEGRATED AGREEMENT. This Agreement (including its Appendices, which
           are incorporated herein by reference) constitutes the complete and
           exclusive statement of the agreement between the parties, and
           supersedes all prior agreements, proposals, negotiations and
           communications between the parties, both oral and written, regarding
           the subject matter hereof.

     16.2. WAIVER OR AMENDMENT. No waiver, alteration or amendment of any of the
           provisions of this Agreement shall be binding unless made in writing
           and signed by each of the parties hereto.

     16.3. NOTICES. Any payment, notice or other communication pursuant to this
           Agreement shall be sufficiently made or given on the date of mailing
           if sent to such party by certified first class mail, postage prepaid,
           return receipt requested addressed to it at its address below or as
           it shall designate by written notice given to the other party.

     If to Metabolix:

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           Metabolix, Inc.
           303 Third Street
           Cambridge, MA 02142
           Attn: President
           Fax: 617-492-1996

     If to Tepha:

           Tepha, Inc.
           303 Third Street
           Cambridge, MA 02142
           Attn: President
           Fax: 617-492-1996

     All such notices, if properly addressed, shall be effective when received.

     16.4. GOVERNING LAW. This Agreement shall be construed, governed,
           interpreted and applied in accordance with the laws of the
           Commonwealth of Massachusetts, without regard to conflict of laws
           principles, and as necessary the laws of the United States of
           America, except that questions affecting the construction and effect
           of any patent shall be determined by the law of the country in which
           the patent was granted. Each party agrees that venue for any dispute
           arising under this Agreement shall be Boston, Massachusetts, and
           waives any objection it has or may have in the future with respect to
           such venue.

     16.5. FAILURE TO EXERCISE REMEDY. If either party fails to enforce any term
           of this Agreement or fails to exercise any remedy, such failure to
           enforce or exercise on that occasion shall not prevent enforcement or
           exercise on any other occasion.

     16.6. NON-EXCLUSIVE RIGHTS. The rights and remedies of the parties provided
           in this Agreement shall not be exclusive and are in addition to any
           other rights and remedies available at law or in equity.

     16.7. ASSIGNMENT. Except as expressly provided in Article 2, neither party
           shall directly or indirectly sell, transfer, assign or delegate in
           whole or in part this Agreement, or any rights, duties, obligations
           or liabilities under this Agreement (collectively "assign"), by
           operation of law or otherwise, without the prior written consent of
           the other party, such consent not to be unreasonably withheld or
           delayed; provided, however, so long as the assignee shall not be a
           competitor of the other party, either party shall have the right to
           assign without consent all of its rights, duties, obligations and
           liabilities under this Agreement to any Affiliate or in connection
           with any sale, merger, consolidation, recapitalization or
           reorganization involving in each case the sale of all the capital
           stock of the party or all or substantially all of the assets of such
           party to which this Agreement relates. Subject to the foregoing, this
           Agreement shall inure to the benefit of and be binding upon the
           permitted successors and assigns of Metabolix and Tepha.

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     16.8. INDEPENDENT CONTRACTORS. The parties agree that in the performance of
           this Agreement they are and shall be independent contractors. Nothing
           herein shall be construed to constitute either party as the agent of
           the other party for any purpose whatsoever, and neither party shall
           bind or attempt to bind the other party to any contract or the
           performance of any obligation or represent to any third party that it
           has any right to enter into any binding obligation on the other
           party's behalf.

     16.9. SEVERABILITY. The provisions of this Agreement are severable, and in
           the event that any provisions of this Agreement shall be determined
           to be invalid or unenforceable under any controlling body of the law,
           such invalidity or unenforceability shall not in any way affect the
           validity or enforceability of the remaining provisions hereof.

     16.10. COUNTERPARTS. This Agreement may be executed in one or more
           counterparts, each of which when executed shall be deemed to be an
           original but all of which taken together shall constitute one and the
           same agreement.

     16.11. PATENT MARKING. Tepha shall apply the patent marking notices
           required by the law of any country where Licensed Products are made,
           used, sold or imported.

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     IN WITNESS WHEREOF, the parties have duly executed this Agreement the day
and year set forth below.

Metabolix, Inc.                         Tepha, Inc.


By: /s/ Oliver P. Peoples               By: /s/ Simon F. Williams
    ---------------------------------       ------------------------------------
Name: Oliver P. Peoples                 Name: Simon F. Williams
Title: Vice President R & D             Title: President
Date: September 9, 2003                 Date: September 9, 2003

*    CONFIDENTIAL TREATMENT REQUESTED


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