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                                                                   EXHIBIT 10.19

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 1st day of October, 1999, (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 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").

                                   WITNESSETH

     WHEREAS, METABOLIX, is the owner of the METABOLIX PATENT RIGHTS (as later
defined herein), and related technology, and has the right to grant licenses
under said METABOLIX PATENT RIGHTS;

     WHEREAS, METABOLIX is the licensee from the Massachusetts Institute of
Technology (hereinafter referred to as "MIT") of the MIT PATENT RIGHTS (as later
defined herein), and has the right to grant sublicenses under said MIT PATENT
RIGHTS;

     WHEREAS, METABOLIX desires to have the PATENT RIGHTS commercialized in the
FIELD OF USE, and is willing to grant a license thereunder; and

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

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

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1.   DEFINITIONS

   For the purposes of this Agreement, the following words and phrases shall
have the following meanings:

     1.1.      "TEPHA" and "METABOLIX" shall include "AFFILIATES" defined as 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, respectively,
               an organization which directly or indirectly controls more than
               fifty percent (50%) of the voting stock of TEPHA or METABOLIX,
               respectively, and an organization the majority ownership of which
               is directly or indirectly common to the ownership of TEPHA or
               METABOLIX, respectively.

     1.2.      "PATENT RIGHTS" shall mean all of the following METABOLIX and MIT
               intellectual property, respectively, the "METABOLIX PATENT
               RIGHTS" and the MIT PATENT RIGHTS":

               1.2.1.    the United States patents listed in Appendix A;

               1.2.2.    the United States patent applications listed in
                         Appendix A and United States patent applications filed
                         after the EFFECTIVE DATE on IMPROVEMENTS, and
                         divisionals, continuations and claims of
                         continuation-in-part applications which shall be
                         directed to subject matter specifically described in
                         such patent applications, and the resulting patents;

               1.2.3.    any patents resulting from reissues or reexaminations
                         of the United States patents described in 1.2.1 and
                         1.2.2 above;

               1.2.4.    the Foreign patents listed in Appendix A;

               1.2.5.    the Foreign patent applications listed in Appendix A,
                         and divisionals, continuations and claims of
                         continuation-in-part applications which shall be
                         directed to subject matter specifically described in
                         such Foreign patent applications, and the resulting
                         patents;

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               1.2.6.    Foreign patent applications filed after the EFFECTIVE
                         DATE on any patent application in 1.2.2 and
                         divisionals, continuations and claims of
                         continuation-in-part applications which shall be
                         directed to subject matter specifically described in
                         such patent applications, and the resulting patents;
                         and

               1.2.7.    any Foreign patents, resulting from equivalent Foreign
                         procedures to United States reissues and
                         reexaminations, of the Foreign patents described in
                         1.2.4, 1.2.5 and 1.2.6 above.

     1.3.      A "LICENSED PRODUCT" shall mean any product or part thereof
               which:

               1.3.1.    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

               1.3.2.    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.

     1.4.      A "LICENSED PROCESS" shall mean any process which:

               1.4.1.    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.

     1.5.      "NET SALES" shall mean TEPHA's and its sublicensees' billings for
               LICENSED PRODUCTS and LICENSED PROCESSES produced hereunder less
               the sum of the following:

               1.5.1.    discounts allowed in amounts customary in the trade;

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

               1.5.3.    outbound transportation prepaid or allowed; and

               1.5.4.    amounts allowed or credited on returns.

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     No deduction shall be made for commissions paid to individuals whether they
     be with independent sales agencies or regularly employed by TEPHA 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 purposes. If a
     LICENSED PRODUCT or LICENSED PROCESS shall be distributed or invoiced for a
     discounted price substantially lower than customary in the trade or
     distributed at no cost to AFFILIATES of TEPHA 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 polymer
     whose composition or manufacture is covered by the PATENT RIGHTS plus other
     materials (such as a growth factor, but not, for example, filler materials)
     that are not 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 polymer divided by the total fully loaded manufacturing cost of
     the total combination material. When the LICENSED PRODUCT consists of a
     combination product consisting of a component made from the polymer, plus
     other components, then "NET SALES" shall mean NET SALES of the total
     product multiplied by the fully loaded manufacturing cost of the polymer
     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.

     1.6.      "FIELD OF USE" shall mean IN VIVO human and veterinary medical
               use of polymers falling within the PATENT RIGHTS, including,
               without limitation, tissue engineering, implantables, medical
               devices, drug delivery and contrast agents, but excluding medical
               disposables, surgical drapes and trays, nutritional and all other
               diagnostic uses. and excluding transgenic plant crop production
               of polymers. "IMPROVEMENT" shall mean an invention conceived
               and/or reduced to practice during the two-year period after the
               EFFECTIVE DATE and dominated by the claims of the PATENT RIGHTS
               listed on Appendix A and owned or CONTROLLED by METABOLIX or
               TEPHA (excluding any preexisting IMPROVEMENT owned or CONTROLLED
               by any entity as of the

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               date it becomes a successor or permitted assignee of METABOLIX
               or TEPHA under Article 11).

     1.7.      "KNOW-HOW" shall mean technical, manufacturing, regulatory and
               other information, methods, specifications, samples, processes,
               procedures, formulations, test data, protocols, and trade secrets
               owned or CONTROLLED by METABOLIX or TEPHA during the two-year
               period after the EFFECTIVE DATE and relating to the PATENT RIGHTS
               or to the development, manufacture or use of any LICENSED
               PRODUCTS or LICENSED PROCESSES (excluding any preexisting
               KNOW-HOW owned or CONTROLLED by any entity as of the date it
               becomes a successor or permitted assignee of METABOLIX or TEPHA
               under Article 11).

     1.8.      "CONTROL" shall mean with respect to any IMPROVEMENTS or
               KNOW-HOW, the possession of the ability to grant a license or
               sublicense with respect thereto as provided for herein.

     1.9.      "FDA" shall mean the United States Food and Drug Administration
               or any successor agency thereof.

2.   GRANT

     2.1.      Subject to the terms and conditions of this Agreement, METABOLIX
               hereby grants to TEPHA the worldwide right and license in the
               FIELD OF USE 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.

     2.2       Under the terms of its license with MIT, METABOLIX has agreed
               that any sublicenses granted by it shall provide that the
               obligations to MIT of articles 2, 5, 7, 8, 9, 10, 12, 13 and 15
               of its license with MIT shall be binding upon the sublicensee as
               if it were a party to that license agreement. METABOLIX further
               has agreed to attach copies of these articles to sublicense
               agreements, and a copy thereof is attached hereto as Appendix C.
               To the extent of any conflict between

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               the terms of this Agreement and Appendix C, as to the MIT PATENT
               RIGHTS only, the terms of Appendix C shall prevail.

     2.3       In order to establish a period of exclusivity for TEPHA,
               METABOLIX hereby agrees that it shall not grant any other license
               to make, have made, use, lease, sell, offer for sale or import
               LICENSED PRODUCTS or to utilize LICENSED PROCESSES in the FIELD
               OF USE and shall not practice under the PATENT RIGHTS for its own
               purposes in the FIELD OF USE during the term of this Agreement;
               provided, however, MIT has reserved the right to practice under
               the MIT PATENT RIGHTS for its own noncommercial research
               purposes.

     2.4       Within six (6) months after the EFFECTIVE DATE, METABOLIX shall
               disclose to TEPHA in writing all METABOLIX-CONTROLLED KNOW-HOW
               not previously disclosed. During the two-year period after the
               EFFECTIVE DATE, each party shall also promptly disclose to the
               other in writing on an ongoing basis all additional KNOW-HOW and
               IMPROVEMENTS. Subject to Article 13 (Confidentiality), METABOLIX
               grants TEPHA the exclusive right and license to use METABOLIX
               KNOW-HOW and METABOLIX IMPROVEMENTS in connection with its
               license hereunder to the PATENT RIGHTS in the FIELD OF USE until
               termination or expiration of this Agreement; provided, however,
               after expiration of this Agreement, TEPHA shall retain a
               perpetual, royalty-free, non-exclusive license to the METABOLIX
               KNOW-HOW. Subject to Article 13 (Confidentiality) and mutually
               agreed upon royalty and other terms, TEPHA grants METABOLIX the
               exclusive right and license to use TEPHA KNOW-HOW and TEPHA
               IMPROVEMENTS in connection with the PATENT RIGHTS outside the
               FIELD OF USE until the last to expire of any patent rights
               covering the TEPHA IMPROVEMENTS; provided, however, after
               expiration of this Agreement, METABOLIX shall retain a perpetual,
               royalty-free, non-exclusive license to the METABOLIX KNOW-HOW.

     2.5       TEPHA shall have the right to enter into sublicensing agreements
               for the rights, privileges and licenses granted hereunder. Upon
               any termination of this

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               Agreement, sublicensees' rights shall also terminate, subject to
               Paragraph 14.6 hereof.

     2.6       TEPHA agrees to incorporate terms and conditions substantively
               similar to Articles 1, 2, 5, 7.1, 8, 9, 10, 11, 12, 13, 14.5,
               14.6, and 16 of this Agreement into its sublicense agreements,
               that are sufficient to enable TEPHA to comply with this
               Agreement.

     2.7       TEPHA agrees to forward to METABOLIX a copy of any and all
               sublicense agreements promptly upon execution by the parties.

     2.8       TEPHA shall not receive from sublicensees anything of value in
               lieu of cash payments in consideration for any sublicense under
               this Agreement, without the express prior written permission of
               METABOLIX.

     2.9       Nothing in this Agreement shall be construed to confer any rights
               upon TEPHA by implication, estoppel or otherwise as to any
               technology or patent rights of METABOLIX, MIT or any other entity
               other than the PATENT RIGHTS, regardless of whether such patent
               rights shall be dominant or subordinate to any PATENT RIGHTS.

3.   DUE DILIGENCE

     3.1.      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.

     3.2.      In addition:

               3.2.1.    TEPHA shall raise in connection with the PATENT RIGHTS
                         and allocated for expenditure for efforts under
                         Paragraphs 3.1 and 3.2, a cumulative total of
                         investment capital and/or research and development
                         funds of: * from the Effective Date. Such cumulative
                         investment capital and/or research and development
                         funds shall include funds invested or

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                         expended by a joint venture in which TEPHA owns at
                         least a thirty-three percent (33%) interest provided
                         that such funds are used substantially for the
                         development and marketing of LICENSED PRODUCTS and
                         LICENSED PROCESSES.

               3.2.2.    TEPHA shall use commercially reasonable efforts to
                         promptly and diligently generate data and perform tests
                         and studies sufficient to file, and shall file, an
                         application for approval by the FDA of a first LICENSED
                         PRODUCT *.

               3.2.3.    TEPHA shall obtain FDA approval of such first LICENSED
                         PRODUCT *.

               3.2.4.    TEPHA shall keep METABOLIX informed of progress in its
                         efforts to develop and commercialize LICENSED PRODUCTS
                         and PROCESSES. METABOLIX shall have the right to
                         contact a representative of TEPHA periodically by
                         telephone to discuss TEPHA's progress with the
                         development of LICENSED PRODUCTS and PROCESSES and
                         sales of such LICENSED PRODUCTS and PROCESSES once
                         launched. In addition, on or before March 1 of each
                         year after the EFFECTIVE DATE until the first
                         commercial sale of a LICENSED PRODUCT, TEPHA shall make
                         a written annual summary report to METABOLIX covering
                         the preceding year ending December 31, regarding the
                         progress toward commercial use of LICENSED PRODUCTS and
                         PROCESSES. All information disclosed by TEPHA to
                         METABOLOX under this provision shall be deemed the
                         Confidential Information (as further discussed in
                         Paragraph 13.1) of TEPHA.

     3.3.      TEPHA's failure to perform in accordance with Paragraphs 3.1 and
               3.2 above shall be grounds for METABOLIX to terminate this
               Agreement pursuant to Paragraph 14.3 hereof; provided, however,
               as to Paragraphs 3.2.2 and 3.2.3, if during the cure period
               provided in Paragraph 14.3, TEPHA shall demonstrate to the
               reasonable satisfaction of METABOLIX that TEPHA shall have
               expended good faith and diligent efforts using reasonable
               resources to meet the milestone(s)

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               and that circumstances beyond TEPHA'S control precluded TEPHA
               from performing in accordance with Paragraph 3.2.2 or 3.2.3, then
               the time for performance of such milestone(s) shall be extended
               for an additional period of six (6) months, or such other period
               as may be mutually agreed.

4.   ROYALTIES

     4.1.      For the rights, privileges and license granted hereunder, TEPHA
               shall pay royalties to METABOLIX in the manner hereinafter
               provided until the expiration of the last to expire of the PATENT
               RIGHTS or until this Agreement shall earlier be terminated:

               4.1.1.    A License Issue Fee of * which said License Issue Fee
                         shall be deemed earned and due in three parts: * in
                         investment capital and/or research and development
                         funds in connection with the PATENT RIGHTS; * due upon
                         the raising by TEPHA of * (cumulatively) in investment
                         capital and/or research and development funds in
                         connection with the PATENT RIGHTS; and * due upon the
                         raising by TEPHA of * (cumulatively) in investment
                         capital and/or research and development funds in
                         connection with the PATENT RIGHTS; provided, however,
                         the full amount of the License Issue Fee shall be due
                         on the third anniversary of the Effective Date,
                         whether or not TEPHA shall have raised such investment
                         capital and/or research and development funds.

               4.1.2.    Milestone payments as follows: * due on filing for
                         approval of the first LICENSED PRODUCT; and * due on
                         FDA approval of the first LICENSED PRODUCT.

               4.1.3.    License Maintenance Fees of * per year payable on
                         January 1, 2003 and on each subsequent January 1 during
                         the term of this Agreement; provided, however, License
                         *.

               4.1.4.    Running Royalties of * of NET SALES of LICENSED
                         PRODUCTS and LICENSED PROCESSES by TEPHA and its
                         sublicensees.

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               4.1.5.    A * share of gross sublicensing revenue (including
                         sublicense issue fees, milestone payments, license
                         maintenance fees and similar consideration but
                         excluding sublicensing revenue from NET SALES covered
                         in Paragraph 4.1.4 above) received by LICENSEE.

     4.2.      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 1.5.2.

     4.3.      No multiple royalties shall be payable because any LICENSED
               PRODUCT, its manufacture, use, lease or sale are or shall be
               covered by more than one PATENT RIGHTS patent application or
               PATENT RIGHTS patent licensed under this Agreement.

     4.4.      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 current conversion
               shall be required in connection with the payment of royalties
               hereunder, such conversion shall be made by using the exchange
               rate prevailing at the Chase Manhattan Bank (N.A.) on the last
               business day of the calendar quarterly reporting period to which
               such royalty payments relate.

     4.5.      To the extent that TEPHA 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 OF USE, TEPHA may
               deduct from the Running Royalty due to METABOLIX under Paragraph
               4.1.4, * of the Running Royalties due on such third party patents
               or intellectual property up to an amount equal to * of the
               Running Royalties due hereunder.

5.   REPORTS AND RECORDS

     5.1.      TEPHA shall keep full, true and accurate books of account
               containing all particulars that may be necessary for the purpose
               of showing the amounts payable

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               to METABOLIX hereunder. Said books of account shall be kept at
               TEPHA's principal place of business or the principal place of
               business of the appropriate division of TEPHA to which this
               Agreement relates. Said books and the supporting data shall be
               open at all reasonable times for * 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 statement or compliance in other respect with this
               Agreement. Should such inspection lead to the discovery of a
               greater than * discrepancy in reporting to METABOLIX' detriment,
               TEPHA agrees to pay the full cost of such inspection.

     5.2.      TEPHA shall deliver to METABOLIX true and accurate reports,
               giving such particulars of the business conducted by TEPHA and
               its sublicensees under this Agreement as shall be pertinent to
               diligence under Article 3 and royalty accounting hereunder:
               before the first commercial sale of a LICENSED PRODUCT or
               LICENSED PROCESS, annually, on January 31 of each year; and after
               the first commercial sale of a LICENSED PRODUCT or LICENSED
               PROCESS, quarterly, within sixty (60) days after March 31, June
               30, September 30 and December 31, of each year. These reports
               shall include at least the following:

               5.2.1.    number and total billings of LICENSED PRODUCTS falling
                         solely within the METABOLIX PATENT RIGHTS manufactured,
                         used or sold by TEPHA and its sublicensees;

               5.2.2.    number and total billings for LICENSED PRODUCTS falling
                         solely within the MIT PATENT RIGHTS manufactured, used
                         or sold by TEPHA and its sublicensees;

               5.2.3.    number and total billings for LICENSED PRODUCTS falling
                         within both the METABOLIX PATENT RIGHTS and the MIT
                         PATENT RIGHTS manufactured, used or sold by TEPHA and
                         its sublicensees;

               5.2.4.    accounting for all LICENSED PROCESSES used or sold by
                         TEPHA and its sublicensees, along with a verification
                         as to each LICENSED PROCESS stating whether it shall
                         fall solely within the METABOLIX

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                         PATENT RIGHTS, solely within the MIT PATENT RIGHTS or
                         both within the METABOLIX PATENT RIGHTS and the MIT
                         PATENTS RIGHTS.;

               5.2.5.    deductions applicable as provided in Paragraph 1.5;

               5.2.6.    Running Royalties due under Paragraph 4.1.4.;

               5.2.7.    royalties due on payments from sublicensees under
                         paragraph 4.1.5.;

               5.2.8.    total royalties due; and

               5.2.9.    names and addresses of all sublicensees of TEPHA. TEPHA
                         shall endeavor to obtain similar information from its
                         sublicensees and shall provide such information which
                         is obtained to METABOLIX.

     5.3.      With each such report submitted, TEPHA shall pay to METABOLIX the
               royalties due and payable under this Agreement. If no royalties
               shall be due, TEPHA shall so report.

     5.4.      On or before the ninetieth (90th) day following the close of
               TEPHA's fiscal year, TEPHA shall provide METABOLIX with TEPHA's
               certified financial statements for the preceding fiscal year
               including, at a minimum, a balance sheet and an operating
               statement.

     5.5.      The amounts due under Articles 4 and 6 shall, if overdue, bear
               interest until payment a per annum rate * in effect at the Chase
               Manhattan Bank (N.A.) 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.   PATENT PROSECUTION

     6.1.      Throughout the term of this Agreement, TEPHA, at its own expense,
               shall file, prosecute and maintain those METABOLIX PATENT RIGHTS
               listed on Appendix B in METABOLIX' name; provided, however,
               METABOLIX shall be entitled to review and comment upon in a
               timely manner all actions undertaken in the prosecution of all
               patents and applications. TEPHA agrees to seek strong,

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               broad claims in the best interest of METABOLIX and shall not
               abandon the subject matter of any substantive claim without the
               prior written permission of METABOLIX, such permission not to be
               unreasonably withheld. If TEPHA shall elect not to file,
               prosecute, or maintain any such METABOLIX PATENT RIGHT, TEPHA
               shall so notify METABOLIX in writing with at least thirty (30)
               days notice prior to any filing, action, payment or the like
               being due, in which event METABOLIX shall have the right to file,
               prosecute, or maintain such METABOLIX PATENT RIGHT, and TEPHA
               shall have no further license rights as to such METABOLIX PATENT
               RIGHT application or patent under this Agreement.

     6.2.      Payment of all out-of-pocket fees and costs relating to the
               filing, prosecution, and maintenance of those METABOLIX PATENT
               RIGHTS listed on Appendix B shall be the responsibility of TEPHA,
               whether such fees and costs were incurred before or after the
               Effective Date of this Agreement. Payment for out-of-pocket costs
               incurred by METABOLIX prior to the Effective Date shall be made
               in three parts:

               6.2.1.    Twenty-Five Percent (25%) on or before a date six (6)
                         months from the Effective Date of this Agreement;

               6.2.2.    Twenty-Five Percent (25%) on or before a date nine (9)
                         months from the Effective Date of this Agreement;

               6.2.3.    The remaining Fifty Percent (50%) on or before a date
                         fifteen (15) months from the Effective Date of this
                         Agreement.

7.   INFRINGEMENT

     7.1.      Each party shall inform the other promptly in writing of any
               alleged infringement of the PATENT RIGHTS by a third party and of
               any available evidence thereof.

     7.2.      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 in the FIELD OF USE and, in
               furtherance of such right, METABOLIX

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               hereby 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. *.

     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
               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 PATENTS RIGHTS in the FIELD of
               USE. 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.
               *.

     7.5.      In the event of the institution of any suit by a third party
               against METABOLIX, TEPHA or its sublicensees for patent
               infringment involving the PATENT RIGHTS in the FIELD OF USE, 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

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               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, *:

               7.6.1.    If the enforceability of all material claims in such
                         PATENT RIGHT claiming the LICENSED PRODUCT or PROCESS
                         is upheld by a court or other legal or administrative
                         tribunal from which no appeal is or can be taken, *
                         or

               7.6.2.    If one or more claims in such PATENT RIGHT covering the
                         LICENSED PRODUCT or 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
                         PROCESS in such country, *.

     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 of
               USE or LICENSED PRODUCTS or 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. As to the MIT PATENT RIGHTS, no settlement,
               consent judgement or other voluntary final disposition of the
               suit may be entered into without the consent of MIT which consent
               shall not unreasonably be withheld. TEPHA shall indemnify MIT
               against any order for

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               costs that may be made against MIT in proceedings commenced and
               defended solely by TEPHA.

     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 OF USE.

8.   PRODUCT LIABILITY

     8.1.      TEPHA shall at all times during the term of this Agreement and
               thereafter, indemnify, defend and hold METABOLIX and MIT, their
               directors, trustees, officers, employees and affiliates, harmless
               against all claims and expenses, arising out of *.

     8.2.      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 MIT 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 MIT as additional named insureds thereunder, shall
               be endorsed to include product liability coverage and shall
               require thirty (30) days written notice to be given to METABOLIX
               and MIT 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.

     8.3.      EXCEPT AS OTHERWISE EXPRESSLY SET FORTH IN THIS AGREEMENT,
               NEITHER PARTY, NOR MIT, NOR THEIR RESPECTIVE DIRECTORS, TRUSTEES,
               OFFICERS, EMPLOYEES, AND AFFILIATES MAKE ANY REPRESENTATIONS OR
               EXTEND ANY WARRANTIES OF

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               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 MIT THAT THE
               PRACTICE OF THE LICENSES GRANTED HEREUNDER SHALL NOT INFRINGE THE
               PATENT RIGHTS OR OTHER INTELLECTUAL OR PROPRIETARY RIGHTS OF ANY
               THIRD PARTY. * TEPHA, MIT OR THEIR RESPECTIVE DIRECTORS,
               TRUSTEES, 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 OR M.I.T. BE ADVISED,
               SHALL HAVE OTHER REASON TO KNOW, OR IN FACT SHALL KNOW OF THE
               POSSIBILITY OF THE FOREGOING.

9.   EXPORT CONTROLS

     9.1.      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

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               approval of such agency. METABOLIX neither represents that a
               license shall not be required nor that, if required, it shall be
               issued.

10.  NON-USE OF NAMES

     10.1.     Except as required by law or in raising funding, neither party
               shall use the names or trademarks of the other, nor of MIT, nor
               any adaptation thereof, nor the names of any of the other party's
               or MIT's employees, in any advertising, promotional or sales
               literature without prior written consent obtained from such
               party, or MIT, or said employee, in each case, such consent not
               to be unreasonably withheld, except that TEPHA may state that it
               is licensed by METABOLIX, or MIT, as applicable, under one or
               more of the patents and/or applications comprising the METABOLIX
               PATENT RIGHTS, or the MIT PATENT RIGHTS, respectively. 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.

11.  ASSIGNMENT

     11.1.     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 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 or substantially all of the capital stock of the
               party or the assets of such party to which this Agreement
               relates. This Agreement shall inure to the benefit of and be

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               binding upon the permitted successors and assigns of METABOLIX
               and TEPHA.

12.  DISPUTE RESOLUTION

     12.1.     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. 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.

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

13.  CONFIDENTIALTIY

     13.1.     Both METABOLIX and TEPHA agree that all 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, trade
               secrets, information, ideas, inventions, materials, samples,
               processes, procedures, methods, formulations, protocols,
               packaging designs and 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.

     13.2.     During the term of this Agreement and thereafter each party shall
               maintain all Confidential Information in confidence and shall not
               disclose any Confidential Information to any third party or use
               any such information for any unauthorized purpose. Each party may
               use such Confidential Information only to the extent required to
               accomplish the purposes of this Agreement. 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.

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

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

               13.3.2.   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;

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               13.3.3.   Information obtained by the receiving party from a
                         third-party source who is not breaching a commitment of
                         confidentiality to the disclosing party by revealing
                         such information to the receiving party;

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

               13.3.5.   Information that is the subject of a granted written
                         permission to disclose that is issued by the disclosing
                         party to the other party;

               13.3.6.   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; or

               13.3.7.   Information provided to consultants, subcontractors or
                         agents for purposes consistent with this Agreement
                         pursuant to a non-disclosure agreement with said
                         parties.

     13.4.     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 Section. 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.

14.  TERMINATION

     14.1.     If TEPHA shall cease to carry on its business, this Agreement
               shall terminate upon notice by METABOLIX, except as provided in
               Article 11 (Assignment).

     14.2.     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

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               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.

     14.3.     Upon any material breach or default of this Agreement by TEPHA,
               other than those occurrences set out in Paragraphs 14.1 and 14.2
               hereinabove, which shall always take precedence in that order
               over any material breach or default referred to in this Paragraph
               14.3, 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.

     14.4.     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 the
               termination.

     14.5.     Upon termination of this Agreement for any reason, nothing herein
               shall be construed to release either party from any obligation
               that matured prior to the effective date of such termination; and
               Articles 1, 8, 9, 10, 12, 13, 14.5, 14.6, and 16 shall survive
               any such termination. TEPHA and any sublicensee thereof may,
               however, after the effective date of such termination, sell all
               LICENSED PRODUCTS in inventory, and complete LICENSED PRODUCTS in
               the process of manufacture at the time of such termination and
               sell the same, provided that TEPHA shall pay to METABOLIX the
               Running Royalties thereon as required by

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               Article 4 of this Agreement and shall submit the reports required
               by Article 5 hereof on the sales of LICENSED PRODUCTS.

     14.6.     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.

     14.7.     Upon termination of this AGREEMENT for any reason *, to all
               information then in TEPHA's possession relevant to the
               commercialization of LICENSED PRODUCTS and/or LICENSED PROCESSES,
               including, but not limited to, KNOW-HOW and IMPROVEMENTS owned or
               controlled by TEPHA as of the effective date of termination
               (whether such know-how and improvements shall be owned or
               CONTROLLED by TEPHA during the two-year period after the
               EFFECTIVE DATE or at any time during the term of this Agreement),
               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. *.

15.  PAYMENTS, NOTICES AND OTHER COMMUNICATIONS

     15.1.     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:

     In the case of METABOLIX:
     President
     METABOLIX, Inc.
     303 Third Street
     Cambridge, Massachusetts 02142

     In the case of TEPHA:
     President

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     TEPHA, Inc.
     303 Third Street
     Cambridge, Massachusetts 02142

16.  MISCELLANEOUS PROVISIONS

     16.1.     This Agreement shall be construed, governed, interpreted and
               applied in accordance with the laws of the Commonwealth of
               Massachusetts, U.S.A., 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.

     16.2.     The parties hereto acknowledge that this Agreement sets forth the
               entire Agreement and understanding of the parties hereto as to
               the subject matter hereof, and shall not be subject to any change
               or modification except by the execution of a written instrument
               subscribed to by the parties hereto.

     16.3.     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.

     16.4.     The failure of either party to assert a right hereunder or to
               insist upon compliance with any term or condition of this
               Agreement shall not constitute a waiver of that right or excuse a
               similar subsequent failure to perform any such term or condition
               by the other party.

     16.5.     TEPHA agrees to mark the LICENSED PRODUCTS sold in the United
               States with all applicable United States patent numbers. All
               LICENSED PRODUCTS shipped to or sold in other countries shall be
               marked in such a manner as to conform with the patent laws and
               practice of the country of manufacture or sale.

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

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METABOLIX, INC.

By:    /s/ Edward M. Muller
       ---------------------------
Name:  Edward M. Muller
       ---------------------------
Title: President
       ---------------------------
Date:  10/1/99
       ---------------------------

TEPHA, INC.

By:    /s/ Simon F. Williams
       ---------------------------
Name:  Simon F. Williams
       ---------------------------
Title: President
       ---------------------------
Date:  October 1, 1999
       ---------------------------

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