EXHIBIT 10.6

                     DEVELOPMENT AND COMMERCIALIZATION AGREEMENT
    
    THIS DEVELOPMENT AND COMMERCIALIZATION AGREEMENT (together with the
attached Schedules, the "Agreement") is made as of this 25th day of September,
1997 (the "Effective Date") by and between Genzyme Transgenics Corporation, a
Massachusetts corporation having a principal place of business at Five Mountain
Road, Framingham, Massachusetts 01701-9322 ("GTC") and B. Braun Melsungen AG, a
German corporation having a principal place of business at Carl-Braun-Stra e 1,
D-34212 Melsungen, Germany ("B. Braun").

1.  Background.

    1.1. GTC.  GTC is a biopharmaceutical company with experience in the
         production of recombinant human proteins in the milk of goats through
         the application of transgenic technology. GTC has the rights to make,
         use and sell transgenically-produced recombinant human [*] ("rh[*],"
         more fully defined below).  

    1.2. B. Braun.  B. Braun is engaged in the development, manufacture and
         sale of pharmaceutical and other products, and is interested in the
         sale and distribution in the Territory (defined below) of Products
         (defined below) which are filled and finished by B. Braun from the
         rh[*] supplied to it by GTC under this Agreement. 

2.  Definitions.

    2.1. "Acceptance Assays" means (a) the assays which are included in GTC's
         BLA for Bulk rh[*], to be listed as part of the Specifications on
         Schedule A to this Agreement, the procedures for the performance of
         which will be transferred to B. Braun by GTC on a schedule to be
         agreed upon by the parties, and (b) such other or additional assays
         which B. Braun and/or GTC is required by the applicable Regulatory
         Authorities to perform for production and/or import of the Bulk rh[*]
         (or any Product properly filled and finished therefrom) into the
         Territory for distribution, sale and use.

    2.2. "Affiliate" means an individual, trust, business trust, joint venture,
         partnership, subsidiary, corporation, association or any other entity
         which (directly or indirectly) is controlled by, controls or is under
         common control with a Party.  For the purposes of this definition, the
         term "control" (including, with correlative meanings, the terms
         "controlled by" and "under common control with") as used with respect
         to any Party, shall mean the possession (directly or indirectly) of at
         least forty percent (40%) of the outstanding voting securities of a
         corporation or comparable equity interest in any other type of entity,
         or the power to control or direct management even in the absence of a
         controlling interest.

    2.3. "BLA" means a United States biologics license application or its
         foreign 


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         equivalent.

    2.4. "Bulk  rh[*]" means transgenically-produced rh[*] supplied to B. Braun
         by GTC under this Agreement.
    
    2.5. "Certificate of Analysis" means a duly authorized, signed and dated
         document accompanying each shipment of Bulk rh[*] from GTC under this
         Agreement which is intended for administration to humans, certifying
         that the Bulk rh[*], identified by batch number, meets the
         Specifications, and that the Transgenic Goats, production processes,
         equipment, materials, facilities and procedures associated with the
         production of such Bulk rh[*] conform to GMP guidelines and all
         applicable regulatory filings.

    2.6. "Confidential Information" means all proprietary information and
         materials, patentable or otherwise, including DNA sequences, vectors,
         cells, substances, formulations, techniques, methodology, equipment,
         data, reports, know-how, sources of supply, patent positioning and
         business plans, including any negative developments, which are
         communicated to, learned of, developed or otherwise acquired by GTC or
         B. Braun, and any other information designated by the disclosing party
         as confidential or proprietary, whether or not related to the Bulk
         rh[*] or Product.  As used in this Agreement, the term "Confidential
         Information" shall be interpreted consistent with the exceptions set
         forth in Section 15.2, below.

    2.7. "Cost of Goods Sold" means, with respect to the manufacture of a
         Product, all direct and indirect labor and overhead, tangible
         materials and supplies, fringe benefits, taxes and charges and direct
         and indirect general and administration charges incurred by B. Braun
         related to the manufacture and sale of the Product, and accounted for
         according to B. Braun's standard accounting practices consistent with
         generally accepted accounting principles.

    2.8. "CPMP" means the Committee for Proprietary Medicinal Products.

    2.9. "Direct Cost" means (a) costs directly attributable to an activity
         (i.e., those costs which vary with such activity), including, but not
         limited to, direct labor and benefit expenses for such activity, and
         consumable bulk and other materials, as determined in accordance with
         generally accepted cost accounting practices in the country of the
         activity, plus (b) fixed overhead costs allocable to the activity,
         including, but not limited to, direct benefit and labor expenses for
         technical services and support services, depreciation, maintenance and
         repairs and insurance costs associated with such activity, as
         determined in accordance with generally accepted cost accounting
         practices in the country of the activity.

    2.10."EMEA" means the European Medicines Evaluation Agency.

    2.11."Field" means the use of rh[*] for medicinal purposes, including,
         without limitation, [*].
    
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    2.12.     "Founder Goat(s)" means a Transgenic Goat from which a Production
              Herd can be produced using standard animal husbandry techniques.

    2.13.     "GMP" means the Good Manufacturing Practice regulations of the
              FDA as described in the United States Code of Federal Regulations
              or any successor regulations and any similar or equivalent
              regulations in the European Community or Japan.

    2.14.     "GTC Patent Rights" means any and all patents and patent
              applications owned or licensed by GTC in which GTC has a
              licensable interest and which exists as of the date of this
              Agreement or which comes into existence during the term of this
              Agreement, including, without limitation, the patents and patent
              applications attached to this Agreement as Schedule B; provided,
              however, such patents and patent applications, if developed by
              GTC during the term of this Agreement, shall be deemed solely  to
              be Project Patent Rights as defined in Section 2.24, below,
              unless GTC can reasonably demonstrate that such patents or patent
              applications were independently developed by GTC  outside of the
              scope of this Agreement.

              GTC Patent Rights shall include any reissues, extensions (or other
              governmental acts which effectively extend the period of 
              exclusivity by the patent holder), substitutions, confirmations, 
              registrations, revalidations, additions, continuations, 
              continuations-in-part, divisions or foreign counterparts of or to
              the foregoing patent rights.

    2.15.     "GTC Technology" means information, data, trade secrets,
              processes, inventions, improvements and know-how which is owned
              or controlled by GTC and in which GTC has a licensable interest,
              and which exists as of the date of this Agreement or which comes
              into existence during the term of this Agreement, related to the
              transgenic production of rh[*], provided, however, such
              technology, if developed by GTC during the term of this
              Agreement, shall be deemed solely to be Project Technology as
              defined in Section 2.25, below, unless GTC can reasonably
              demonstrate that such technology was independently developed by
              GTC outside of the scope of this Agreement.

    2.16.     "rh[*]" means the recombinant human [*] produced by Transgenic
              Goats in the Production Herd pursuant to the terms and conditions
              of this Agreement and in accordance with the protocols and
              specifications established herein.

    2.17.     "IND" means an Investigational New Drug application or its
              equivalent for initiating clinical trials in the United States or
              any corresponding foreign application, registration, or
              certification. 

    2.18.     "Koseisho" means the Japanese Ministry of Health. 

    2.19.     "Net Sales Price" means the gross billing price derived by or
              payable to B. Braun and its Affiliates and permitted sublicensees
              from or on account of the sale 

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              of Product to third parties which are not Affiliates of B. Braun,
              less: (a) customary trade, quantity or cash discounts or rebates 
              allowed; (b) amounts rebated, refunded or credited for rejected 
              or returned Products or because of retroactive price reductions, 
              rebates or chargebacks; (c) customs duties, consular fees and 
              other like charges; (d) sales, use, turnover, excise taxes, or 
              other governmental charges levied on or measured by sales, but not
              franchise or income taxes; (e) uncollected accounts receivable
              attributable to sales of Products; and (f) transportation,
              freight and handling charges, and insurance on shipments to
              customers.  Transfer of a Product by B. Braun to an Affiliate
              shall not be considered a sale.

              In the event any Product is sold as a component of a combination 
              of functional elements, Net Sales Price for purposes of 
              determining royalty payments on such combination shall be 
              calculated on a country-by-country basis by multiplying the 
              average per unit Net Sales Price of the Product portion of the
              combination when sold separately in the applicable country during
              the accounting period in which the sale was made by the number of
              units of Product sold as part of such combination product. In the
              event no separate sales of the Product were made in the applicable
              country during the applicable accounting period, the Net Sales 
              Price of such Product shall be determined by the Liaison 
              Committee.

    2.20.     "Parties" means GTC and B. Braun; "Party" means GTC or B. Braun.

    2.21.     "Product" means a product consisting of rh[*]-solution(s) and/or
              rh[*]-powder (bulk) as a component meeting the Specifications
              established by Schedule A.

    2.22.     "Purchase Price" means the prices per gram for Bulk rh[*] sold by
              GTC to B. Braun, as provided in Section 7.2, below.

    2.23.     "Production Herd" means a line of female Transgenic Goats derived
              from a Founder Goat.

    2.24.     "Project Patent Rights" means (a) all patent applications
              established by one or both of the Parties in performance of this
              Agreement and hereafter filed or having legal force in any
              country, which claim a composition, method or process relating to
              Project Technology, together with any and all patents that have
              issued or in the future issue therefrom, and (b) all related
              divisionals, continuations, continuations-in-part, reissues,
              renewals, extensions or additions to any such patents and patent
              applications.

    2.25.     "Project Technology" means information, data, trade secrets,
              processes, inventions, improvements and know-how established by
              one or both of the Parties in performance of this Agreement.

    2.26.     "Regulatory Authority" shall mean the United States Food and Drug
              Administration (the "FDA") and similar government agencies
              throughout the world, including, without limitation, the EMEA
              and/or the CPMP, which regulate 

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              the manufacture and marketing of Bulk rh[*] and/or the Product 
              in Europe, and the Koseisho, which regulates the manufacture 
              and marketing of Bulk rh[*] and/or the Product in Japan.

    2.27.     "SOP" has the meaning assigned to it in Section 4.2.

    2.28.     "Specifications" means the specifications and test methods for
              Bulk rh[*] sold by GTC to B. Braun, to be set forth in Schedule A
              to this Agreement, which Schedule may be amended from time to
              time only by written agreement of the Parties.  The
              Specifications shall meet the requirements (including, without
              limitation, stability and release testing requirements) of each
              applicable Regulatory Authorities for import of the Bulk rh[*]
              (or any Product properly filled and finished therefrom) into the
              applicable country or countries in the Territory for
              distribution, sale and use. 

    2.29.     "Territory" means [*].  In the event B. Braun exercises its
              Co-Marketing Option set forth in Section 8.1, below, the
              Territory shall include [*], on a co-exclusive basis.

    2.30.     "Transgenic Goat" means a goat whose genome has been modified by
              the incorporation of exogenous DNA, including, but not limited
              to, DNA encoding rh[*], and which meets the Specifications set
              forth in Schedule A.

    2.31.     "Pivotal Clinical Trial " meansthe final clinical trial which is
              deemed necessary by the applicable Regulatory Authority in a
              country in the Territory to support the filing of a BLA for
              approval to market and sell the Product in such country.

    2.32.     Singular/Plural.  The singular shall include the plural and the
              plural the singular for the terms defined in this Section 2.

3.  Liaison Committee.   Within thirty (30) days of the Effective Date, GTC and
    B. Braun shall form a committee (the "Liaison Committee") to coordinate and
    communicate the results of the Parties' activities under this Agreement. 
    The Liaison Committee shall consist of four (4) members, two (2) of whom
    shall be designated by GTC and two (2) of whom shall be designated by B.
    Braun.  Each Party may assign its members to the Liaison Committee as it
    deems appropriate, and designated substitutes may represent Liaiso
    Committee members at regularly scheduled meetings at the discretion of the
    substituting Party.  The Liaison Committee will meet at least once per
    calendar quarter, alternating between GTC and B. Braun locations, to assess
    the progress under this Agreement.  In addition to reports to, and meetings
    of, the Liaison Committee, there will be frequent communications among the
    scientists and project managers to keep B. Braun and GTC advised of current
    activities, research, testing and achieved results of the Parties under
    this Agreement.

4.  Development and Manufacture of Bulk rh[*].

    4.1. Agreement to Develop and Manufacture.  GTC agrees to use commercially

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         reasonable and diligent efforts to (a) develop a Production Herd of
         Transgenic Goats to produce rh[*] in their milk, (b) meet the
         milestones and perform the activities set forth in Section 4.7 and, if
         B. Braun exercises its co-marketing option under Section 8.1, below,
         in Section 8.3 of this Agreement, and undertake the activities shown
         in Schedule C to this Agreement, and (c) supply B. Braun with its
         requirements of Bulk rh[*], on the terms and conditions set forth in
         this Agreement.  Schedule C to this Agreement sets forth a schematic
         estimated timeline of GTC's development plan.  In the event of any
         conflict between the text of this Agreement and the schematic
         timeline, the text of this Agreement shall control.  In performing
         their obligations under this Agreement, the Parties shall keep each
         other informed, via the Liaison Committee, of Project Patent Rights
         and Project Technology developed during the term of this Agreement.

    4.2. Good Agricultural Practices.  GTC  shall use Good Agricultural
         Practices ("GAP") in the development of Transgenic Goats pursuant to
         this Agreement.  GAP shall be defined as a series of standard
         operating procedures ("SOPs") covering recovery of fertilized eggs,
         pronuclear microinjection, embryo transfer, pregnancy, delivery,
         rearing and milking of the Transgenic Goats.

    4.3. In Accordance with Specifications.  All Bulk rh[*] ordered by B. Braun
         under this Agreement shall conform to Specifications.  With respect to
         the countries in the Territory, GTC shall be responsible for ensuring
         that the Specifications comply with any licenses and approvals
         including, without limitation, the licenses and approvals necessary to
         export the Bulk rh[*] and any outright Product in such countries on a
         country-by country basis, including all then-current licenses and
         approvals granted or issued to GTC by the relevant Regulatory
         Authorities.

    4.4. Establishment of and Changes to Specifications.  As set forth in
         Section 2.28, the Specifications may be modified from time to time
         only by written agreement of the Parties.  B. Braun shall not propose
         to any Regulatory Authority the establishment of any Specification, or
         any changes to the Specifications, or in any methods for testing the
         Bulk rh[*] and/or the Product to assess conformity thereof with the
         Specifications (e.g., the Acceptance Assays), without GTC's prior
         written consent, which consent shall not be unreasonably withheld. 
         GTC shall have the right to consult in advance with B. Braun for, and
         to participate with B. Braun in, any such discussions with Regulatory
         Authorities which could lead to the establishment of any
         Specifications, or any required or recommended changes in the
         Specifications or associated testing methods.   

    4.5. Quality Control and Analysis.

         a.   GMP Compliance.  All Bulk rh[*] supplied by GTC shall meet the
              GMP guidelines required by the applicable Regulatory Authorities
              and shall meet the Specifications, on a country-by country basis,
              and such other specifications as are mutually agreed upon by GTC
              and B. Braun.  The facilities and Transgenic Goats utilized by
              GTC to make Bulk rh[*] shall comply with the Regulatory Authority
              license requirements.  GTC shall 

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              maintain such records and data as are necessary to ensure that 
              the manufacture of such Bulk rh[*] can be demonstrated to comply
              with such guidelines and requirements.  GTC agrees to furnish to 
              B. Braun certification in such form as is required by the 
              applicable Regulatory Authorities and other governmental agencies
              with proper jurisdiction that the manufacture of such Bulk rh[*]
              complies with such guidelines and requirements.

         b.   Release Testing.  GTC shall be solely responsible for performing
              stability and release testing for the Bulk rh[*] available for
              purchase by B. Braun.  As part of its fill/finish activities
              under this Agreement, B. Braun shall be solely responsible for
              stability and release testing of all final Product available for
              distribution and/or sale by B. Braun.  

         c.   Documentation and Inspections.

              i.   Documents.  GTC shall provide B. Braun with copies of any
                   records, documentation and technical assistance which may be
                   reasonably required for B. Braun or any of its Affiliates or
                   Sublicensees of the Product to obtain from the appropriate
                   Regulatory Authorities approval to import and use the Bulk
                   rh[*], based on GTC's manufacture of such Bulk rh[*].  B.
                   Braun shall provide GTC with copies of all documentation
                   pertaining to Bulk rh[*] and/or the Product prior to
                   submission of such documentation to the applicable
                   Regulatory Authorities.  Each Party shall  promptly review
                   such documentation and provide the other Party with any
                   comments it may have concerning such documentation and/or
                   the form in which any such information is delivered to such
                   Regulatory Authorities.
         
              ii.  Right to Inspect.  B. Braun, at its own expense, shall have
                   the right, from time to time, to send its technical and
                   quality personnel to GTC's manufacturing facilities to
                   inspect and audit the manufacturing and storage facilities
                   allotted to the Bulk rh[*] and to inspect and audit the
                   records (except for financial records) and documentation
                   related to the Bulk rh[*].   Upon prior notice to GTC, all
                   such personnel and representatives shall be freely admitted
                   by GTC for such purposes during reasonable and regular
                   business hours.  All such personnel shall be required to
                   sign usual and customary confidentiality agreements and to
                   follow GTC's safety rules and procedures in effect at the
                   production facility.

    4.6. Subcontracting.  GTC's obligations under this Agreement may be
         delegated to and fulfilled by Affiliate and/or non-Affiliate
         subcontractors (i.e., by third party designees); provided, however,
         (a) B. Braun shall have the right to consent to such subcontractors,
         (b) such subcontracting shall be on terms and conditions fully
         consistent with the terms and conditions of this Agreement and (c) GTC

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         shall remain fully responsible for the performance of all of its
         obligations under this Agreement, notwithstanding any such
         subcontracting.

    4.7. Development Compensation.  In accordance with the following schedule,
         B. Braun shall pay GTC the following payments in consideration of
         GTC's development of  rh[*]: 

                                                                 Estimated
              Milestone                                          Completion Date

         a.   Base Fee.  [*] within [*].

         b.   [*] within [*].  The successful transgenic 
              identification of the Transgenic Goats will be
              determined by polymerase chain reaction ("PCR")
              of goat blood and ear biopsy.  Transgenic
              identification will be confirmed and 
              characterized by Southern  blotting.

         c.   [*].

         d.   [*].  GTC shall update this commercial report
              at each separate stage/milestone under this 
              Agreement.

         e.   [*].

         f.   [*].  The Liaison Committee shall consider 
              using McGaw, Inc. of Irvine, California as 
              the contract research organization for the 
              performance of such preclinical studies.

         g.   [*].

         h.   [*].  The clinical plan for such trial shall 
              be developed in consultation with the Liaison 
              Committee. 

         i.   [*].

    [*].  The estimated completion date for the milestones set
    forth above refer to the last day of the specified month.

    [*].

    4.8. Payments.  All payments to GTC under this Agreement 
         will be made in U.S. Dollars by wire transfer of good
         and immediately available funds to GTC's bank account
         at [*], or by any other means agreed upon by the
         Parties.  Payments 

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           made to GTC under this Section 4 shall be made in United States 
           Dollars without regard to changes in exchange rates. 

    4.9.   Capital, Facilities and Personnel.  To the extent commercially
           reasonable, GTC shall at all times possess sufficient capital,
           facilities (directly or through third parties)(including warehouse
           facilities) and administrative personnel to support GTC's obligations
           under this Agreement.

    4.10.  Inventory.  GTC shall maintain a sufficient inventory of Bulk
           rh[*] and/or components thereof to provide delivery of Bulk rh[*]
           to B. Braun under the terms and conditions of this Agreement.

5.  Purchase and Supply Terms and Conditions.  B. Braun agrees to purchase all
    of its requirements of Bulk rh[*] from GTC, and GTC agrees to supply B.
    Braun with such requirements, on the terms and conditions set forth in this
    Agreement. The obligations of the Parties with respect to projections,
    forecasts and purchase orders are set forth in Sections 5.1 through 5.5,
    below.

    5.1. Initial Five Year Sales Projection and Updates.  Promptly following
         the Effective Date, B. Braun will provide GTC with an initial
         projection of the amount of Product B. Braun expects to sell during
         [*] (or such other launch date as specified by the Liaison Committee)
         and each of the next four (4) successive calendar years, subject to
         applicable Regulatory Authority approvals in the Territory. 
         Thereafter, on or before January 1st in each year, B. Braun will
         provide GTC with an updated projection of the amount of Product B.
         Braun expects to sell during the subsequent calendar year and each of
         the next four (4) successive calendar years.  Such projections shall
         be used by GTC for planning purposes only and shall not create binding
         sales or purchase obligations for either Party hereto.  GTC and B.
         Braun will meet periodically to review B. Braun's projected
         requirements for Bulk rh[*].
    
    5.2. Initial Four Quarter Forecast.  Within fifteen (15) business days of
         the date GTC or  B. Braun notifies the other Party that it (or its
         Affiliate or third party designee) has completed a Pivotal Clinical
         Trial of rh[*], B. Braun will provide GTC with an initial, non-binding
         four-quarter forecast of the amount of Bulk rh[*] B. Braun expects to
         purchase from GTC during the four (4) calendar quarters commencing
         nine (9) months following completion of such Pivotal Clinical Trial.

    5.3. First Purchase Order and Updated Forecast.  At a time to be determined
         by B. Braun, B. Braun will provide GTC with: 

         a.   First Purchase Order.  A first purchase order specifying the
              amount of Bulk rh[*] to be delivered to B. Braun nine (9) months
              after such purchase order; and

         b.   Updated Four-Quarter Forecast.  An updated four-quarter forecast
              of 

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              the amount of Bulk rh[*] B. Braun expects to purchase from GTC
              during each of the second, third and fourth calendar quarters
              covered by, and the next calendar quarter following, the
              preceding four-quarter forecast.        

    5.4. Subsequent Purchase Orders and Updated Forecasts.  On or before the
         first day of each subsequent calendar quarter, B. Braun will provide
         GTC with: 

         a.   Quarterly Purchase Orders.  A purchase order specifying the
              amount of Bulk rh[*] to be delivered to B. Braun during the
              calendar quarter which begins nine (9) months from the date of
              such purchase order; and

         b.   Updated Four-Quarter Forecasts.  An updated four-quarter forecast
              of the amount of Bulk rh[*] B. Braun expects to purchase from GTC
              during each of the second, third and fourth calendar quarters
              covered by, and the next calendar quarter following, the
              preceding four-quarter forecast.
         
    5.5. Good Faith Projecting and Forecasting.  In preparing the projections
         and forecasts, B. Braun shall use commercially reasonable and diligent
         efforts to accurately predict its Product sales and actual
         requirements for Bulk rh[*].
    
    5.6. Minimum Purchase and Maximum Supply Commitments.  For each calendar
         quarter commencing six (6) months following filing by GTC or B. Braun
         (or their respective  Affiliates or third party designees) of a BLA
         for  rh[*], B. Braun shall be obligated to purchase at least eighty
         percent (80%) of the amount of Bulk rh[*] forecasted for such quarter
         in the most recent four-quarter forecast, subject to ongoing
         Regulatory Authority approval (and any other necessary approvals) to
         sell Products; and GTC shall be obligated to supply up to, but not
         more than, one hundred twenty percent (120%) of the amount forecasted
         for such quarter in the most recent four-quarter forecast.  B. Braun's
         minimum purchase obligations under this Section shall be reduced
         adequately in the event that a Regulatory Authority in a country in
         the Territory has prohibited B. Braun from selling Product in such
         country.  

    5.7. Purchase Orders.
       
         a.   Submission by B. Braun.  All orders for Bulk rh[*] by B. Braun
              shall be made by submission to GTC of a purchase order specifying
              the quantity of Bulk rh[*] ordered and the requested delivery
              date(s), and shall be consistent with the terms of this
              Agreement.
    
         b.   Acceptance by GTC.   Subject to the terms and conditions of this
              Agreement, GTC shall be required to accept purchase orders which
              conform to the limitations and requirements of Section 5.6 of
              this Agreement.  GTC shall notify B. Braun within ten (10)
              working days of receipt regarding the acceptance or permitted
              rejection of a purchase order.

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         c.   Order Lead Time.  A nine (9) month period is required from the
              date GTC receives an accepted purchase order to the availability
              of Bulk rh[*] for delivery under such purchase order to allow for
              scheduling, preparation and testing of the Bulk rh[*] for
              delivery to B. Braun.  This order lead time is required for all
              purchase orders, no matter what their magnitude. 
         
    5.8.  Delivery.  GTC shall deliver Bulk rh[*] to B. Braun or its designated
          carrier at the times and in the amounts specified in each accepted
          purchase order, provided that the lead times and quantities specified
          in the purchase order conform with this Agreement. 
 
    5.9.  Documentation.  Each shipment of Bulk rh[*] shall be accompanied by a
          Certificate of Analysis, in a form required for release of the Product
          in the Territory following fill and finish by B. Braun, together with
          such other documentation, if any, that is required by customs
          regulations for export/import of the Bulk rh[*] into countries in the
          Territory where the Product will be filled and finished in final
          dosage form suitable for sale.  B. Braun shall be responsible for
          conducting tests and submitting results which may be required by
          Regulatory Authorities for import of Bulk rh[*] into the Territory.

    5.10. Terms and Conditions of Sale.  All sales of Bulk rh[*] under this
          Agreement shall be X WORKS ("EXW", as defined in INCOTERMS,
          International Chamber of Commerce, 1990 edition) GTC's designated
          production facility.  Notwithstanding any proposed variation from
          or addition to such terms and conditions appearing on any
          purchase order, invoice or any other directions, notices or
          instructions submitted by B. Braun, the terms and conditions of
          this Agreement shall prevail, unless otherwise agreed to in
          writing by the Parties.  All freight, insurance and other
          shipping arrangements, and the costs and expenses thereof, shall
          be made and borne by B. Braun; and all packaging arrangements
          necessary to ship the Bulk rh[*] safely and properly, and the
          costs and expenses thereof, shall be made and borne by GTC.  All
          required shipping conditions and methods will be established and
          validated by GTC in collaboration with B. Braun.  Subject to the
          foregoing, title to, and ownership and risk of loss of, the Bulk
          rh[*] shall pass to B. Braun upon delivery of the Bulk rh[*] to
          the custody and control of B. Braun's designated carrier at GTC's
          designated production facility.

6.  Acceptance Testing; Filling and Finishing.
    
    6.1.  Testing.   For each shipment of Bulk rh[*], B. Braun shall have the
          right, within thirty (30) business days of receipt of a shipment, to
          test each shipment, using the Acceptance Assay, in order to verify
          that the material received by B. Braun meets the Specifications for
          such Bulk rh[*], consistent, within the expected variability of such
          Acceptance Assay.  All Bulk rh[*] which is found by B. Braun, in its
          performance of the Acceptance Assay, to be in  conformance with the
          Specifications, notwithstanding any variations between the results of
          GTC's 

                                       11
*Confidential Treatment has been requested for the marked portion.


         release testing and B. Braun's Acceptance Assay, shall be held
         to comply with the Specifications.  B. Braun shall promptly inform GTC
         of any discrepancies outside of the expected variability of the
         Acceptance Assay discovered by B. Braun in performing such Acceptance
         Assay.  Such shipment shall be held to comply with the Specifications,
         unless, within such thirty (30) day period, B. Braun gives GTC written
         notice, together with supporting documentation, of non-conformance
         with the Specifications discovered by B. Braun.  Upon receipt of such
         notice, GTC will be given access to such shipment in order to conduct
         its own inspection thereof (which inspection shall be conducted within
         thirty (30) days of such notice), and the Parties will endeavor to
         agree in good faith as to whether such shipment complies with the
         Specifications for such Bulk rh[*].  

         Notwithstanding the foregoing, in the event the Bulk rh[*] delivered
         to B. Braun under this Agreement is determined, within one (1) year
         from B. Braun's receipt of the Certificate of Analysis including the
         release for such Bulk rh[*] (using the procedures set forth in Section
         6.1, above) not to comply with the Specifications, and such
         non-compliance was not detected at the time of delivery  (a "hidden
         defect"), then GTC shall reimburse B. Braun for its direct
         out-of-pocket costs associated with the manufacture and any recall of
         such Product resulting from such hidden defect.
         
    6.2. Dispute Resolution.  If the Parties are unable, after good faith
         efforts, to agree within a reasonable time as to any matter set forth
         in Sections 6.1 of this Agreement, such matter will be submitted to an
         independent quality control laboratory agreed upon by the Parties. 
         With respect to conformance with the Specifications, if either  GTC
         concedes or the independent laboratory finds that the Bulk rh[*]
         shipped to B. Braun does not conform with the Specifications
         applicable for such shipment, GTC, at B. Braun's option, either shall
         supply B. Braun, as soon as possible and at no additional cost to B.
         Braun, with an equivalent quantity of Bulk rh[*] which meets the
         Specifications, or refund to B. Braun the purchase price for such
         non-conforming Bulk rh[*].  In such event, B. Braun will return to GTC
         all non-conforming Bulk rh[*] in accordance with GTC's instructions,
         at GTC's cost and expense.  If either B. Braun concedes or the
         independent laboratory finds that GTC's release testing results are
         determinative and that such batch complies with the Specifications,
         GTC shall have no replacement or refund obligations with respect to
         such shipment.  The cost of inspections and/or testing conducted by
         the independent laboratory shall be borne by the Party whose
         determinations with respect to such batch are contrary to the findings
         of the independent laboratory.

    6.3. Returns.  Transfer of title and risk of loss for Bulk rh[*] returned
         to GTC pursuant to this Section 6 shall pass to GTC when such returned
         Bulk rh[*] is placed in the custody and control of GTC's designated
         carrier, consistent with GTC's instructions.  The cost of freight,
         insurance and handling and other similar costs shall be paid by GTC. 
         All amounts due by one Party to the other by virtue of this subsection
         shall be paid within forty-five (45) days of the end of the month in
         which they were invoiced.

                                       12
*Confidential Treatment has been requested for the marked portion.


    6.4. B. Braun to Fill, Finish and Label Product.  B. Braun shall fill,
         finish and label the Product in final dosage form suitable for sales
         in the Territory, from the Bulk rh[*] supplied to B. Braun by GTC
         under this Agreement.

    6.5. Expense and Damage Reimbursement.  In the event GTC is held to have
         willfully breached its manufacturing and delivery obligations under
         this Agreement or is held to have been negligent in the manufacture
         and delivery of Bulk rh[*] under this Agreement, GTC shall reimburse
         and compensate B. Braun for its direct damages and expenses incurred
         by B. Braun as a result thereof, unless otherwise stipulated in
         Section 12, below. 

7.  Purchase Price and Payment Terms.

    7.1. Bulk rh[*] for Pivotal Clinical Trials.  GTC will sell Bulk rh[*] to
         B. Braun for use in clinical trials at a Purchase Price (per gram)
         equal to GTC's Direct Costs or manufacturing, EX WORKS ("EXW", as
         defined in INCOTERMS, International Chamber of Commerce, 1990 edition)
         GTC's designated production facility.

    7.2. Bulk rh[*] Intended for Commercial Sale.  

         a.   Purchase Price.  GTC will sell Bulk rh[*] to B. Braun for
              filling, finishing, labeling and sale as a commercial Product
              after B. Braun obtains Regulatory Authority approval necessary to
              sell the Product, at a Purchase Price (per gram) set forth below:

                   Quantity Purchased         
                   in Calendar Year       Purchase Price (U.S. Dollars)
    
              [*]

         b.   Minimum Annual Purchase Requirement; Conversion to Co-Exclusive
              Rights in Territory.  B. Braun has investigated the market
              potential in the Territory for the Product, taking into account
              all relevant factors.  Based on this investigation, B. Braun has
              agreed to purchase [*].  For purposes of calculating minimum
              annual purchase requirements, the Parties shall consider on
              purchases of Bulk rh[*] from GTC for sale in the Territory (i.e.,
              not for sales in [*] pursuant to B. Braun's Co-Marketing Option). 
              In the event B. Braun fails to purchase the applicable minimum
              annual purchase requirement in any calendar year after utilizing
              commercially reasonable efforts, GTC's sole remedy shall be to
              appoint itself (or its designee) as a co-exclusive distributor
              (with B. Braun) of the Product in the Territory; provided,
              however, B. Braun may, at its option, preserve exclusivity if,
              prior to the end of the calendar in which additional minimum
              annual purchase requirement payments are due, it pays to GTC the
              balance of the applicable annual minimum purchase requirement
              then due for such calendar year.   B. Braun's minimum purchase
              obligations under this Section shall be subject to reduction or
              suspension, as determined in good 

                                       13
*Confidential Treatment has been requested for the marked portion.


              faith by the Liaison Committee, in the event of force majeure 
              or legal or Regulatory Authority prohibition or registration 
              schedule delay to sell Product in a country in the Territory.  

    7.3. Invoice and Payment.  GTC shall invoice B. Braun for the purchase
         price associated with each shipment of Bulk rh[*] at the time of
         shipment.  B. Braun shall make such payments to GTC within forty-five
         (45) days of receipt of the applicable invoice.  B. Braun will pay GTC
         by wire transfer of good and immediately available funds to a bank and
         account, as specified in writing by GTC, or by any other means agreed
         upon by the Parties.  In the event the exchange rate of the German
         Mark (and subsequently the EURO currency) and the United States Dollar
         increases or decreases from the exchange rate applicable on the
         Effective Date of this Agreement (in the case of conversion from the
         EURO currency, from fixation of the exchange rate between the
         applicable currency to the EURO) by more than ten (10) percent, an
         adjustment in the payment due GTC under this Section 7 shall be made
         on a payment-by-payment basis, whereby each Party will equally share
         such increase or decrease.   The basis for determining the exchange
         rates in effect for the purposes of this Section shall be the exchange
         rate for the average of the "buy and sell" rates as published in the
         European Edition of the Wall Street Journal on the date of shipment of
         the applicable order of Bulk rh[*].

    7.4. Taxes.  All sales, use, transfer and other taxes and duties imposed
         with respect to the Bulk rh[*] or their sale by GTC to B. Braun by any
         governmental authority (but excluding any income or franchise taxes of
         any kind imposed on GTC) shall be paid by B. Braun, as adjusted if
         necessary.  The Parties shall cooperate in obtaining and providing to
         each other any certificates of exemption or similar document required
         to exempt any sales, use or similar tax liability.

8.  [*] Co-Marketing Option.  

    8.1. Exercise by B. Braun.  GTC grants to B. Braun an option (the
         "Co-Marketing Option") to appoint itself (or a wholly-owned
         subsidiary) as a co-exclusive distributor (with GTC) of the Product in
         [*], by giving GTC written notice at any time prior to October 2,
         1998.  If B. Braun exercises the Co-Marketing Option, B. Braun and GTC
         shall co-market the Product in [*]; and GTC shall continue to supply
         B. Braun with its requirements of Bulk rh[*] under the terms and
         conditions of this Agreement.  The form of the co-marketing
         arrangement shall be agreed upon by the Parties.

    8.2. No Right to Sublicense or Appoint Subdistributors.  B. Braun's right
         to market, distribute and sell the Product in [*] (itself or through
         an Affiliate) may not be sublicensed to third parties which are not
         Affiliates, nor may B. Braun appoint a subdistributor for such
         Product, without GTC's prior written consent.  

                                       14
*Confidential Treatment has been requested for the marked portion.


    8.3. Consideration.  In consideration of the grant of the Co-Marketing
         Option and in accordance with the following schedule, B. Braun shall
         pay GTC the following payments: 


                                                                Estimated
         Milestone                                              Completion Date

         [*]

         d.   [*].  The Liaison Committee shall consider 
              using McGaw, Inc. of Irvine, California as the
              contract research organization for the 
              performance of such preclinical studies.

         e.   [*].

         f.   [*].  The clinical plan for such trial shall 
              be developed in consultation with the Liaison 
              Committee.

         g.   [*].

    8.4. Payments.  All payments to GTC under this Agreement will be made by
         wire transfer of good and immediately available funds to a bank and
         account, as specified in writing by GTC, or by any other means agreed
         upon by the Parties.    Payments made to GTC under this Section 8
         shall be made in United States Dollars without regard to changes in
         exchange rates. 

9.  B. Braun Obligations to Purchase, Market and Sell Product.

    9.1. Purchase Obligation.  B. Braun shall be obligated to purchase from GTC
         one hundred percent (100%) of its and its Affiliates and distributors
         requirements of  rh[*] for filling, finishing, labeling and sales as a
         commercial Product.  Preclinical studies of such  rh[*] shall be
         conducted by or on behalf of GTC.  B. Braun, at its cost and expense,
         will process the Bulk rh[*] supplied by GTC and formulate Products
         therefrom.  With the exception of GTC's obligations hereunder, B.
         Braun shall conduct all necessary testing, and shall make all
         regulatory filings, necessary to market and sell Products in the
         Territory.  GTC shall provide B. Braun with all data which relates to
         Bulk rh[*] produced under this Agreement and GTC's performance of its
         obligations under this Agreement which is reasonably necessary to
         support such regulatory filings.

    9.2. Area of Activity.  B. Braun shall concentrate its activities in
         respect of the Product within the Territory.  B. Braun shall not,
         outside the Territory: (a) seek customers for the Product; (b)
         establish any branch or facility to sell the Product; or (c) maintain
         any distribution depot for the Product.  B. Braun shall not be in
         breach of this Section, nor of its obligation to sell Product only in
         the Territory, if a third party which is not an Affiliate or
         subdistributor of B. Braun sells Product outside the 

                                       15
*Confidential Treatment has been requested for the marked portion.


         Territory.

    9.3. Activities.  With regard to the final manufacture and marketing of
         Product, B. Braun's obligations under this Agreement shall include,
         but shall not be limited to, the activities set forth in this Section
         9.3: 

         a.   Product Testing, Labeling and Packaging; Reimbursement of Direct
              Costs.

              i.   Testing for Import, Distribution and Sale.  B. Braun shall
                   perform all testing required to import the Bulk rh[*] to the
                   Territory and distribute and sell the Product in the
                   Territory.  GTC shall have the right, from time to time, to
                   send its technical and quality personnel to B. Braun's
                   facility to inspect such testing facilities and to inspect
                   and audit the records and documentation related thereto.  B.
                   Braun shall not subcontract such testing to a third party
                   which is not a B. Braun Affiliate, without GTC's prior
                   written consent.
         
              ii.  Labeling and Packaging.  B. Braun shall label and package
                   all Product for marketing, distribution and sale in the
                   Territory. 
              
              iii. Inspection and Release of Product.  B. Braun shall be
                   responsible for and shall perform all inspections required
                   to release, distribute and sell the Product in the
                   Territory.

         b.   Promotion and Advertising.   B. Braun shall conduct commercially
              reasonably educational, promotional and advertising activities
              with respect to the Product in the Territory, and in so doing B.
              Braun shall perform the following activities:

              i.   Country Symposia and Trade Shows.  B. Braun may provide
                   representatives from within its organization to participate
                   in country and local trade and industry meetings,
                   conventions, shows, symposia and congresses to advance the
                   sales of the Product.
         
              ii.  Advertising.  To the extent commercially reasonable, B.
                   Braun will actively advertise and promote the Product in the
                   Territory utilizing media and other means of communication
                   commonly employed in the industry.

         c.   Distribution, Marketing and Sales.  To the extent commercially
              reasonable, B. Braun will distribute, market and sell the Product
              throughout the Territory, and in so doing will establish, train,
              manage and fund a sales force to cover the Territory.  The
              selection of qualified technical and other personnel for the
              sales force shall be at B. Braun's sole discretion.  The sales
              force will offer support to health care professionals and
              customers of the Product, including, without limitation, such
              technical advice, assistance, training and field services as will
              promote customer satisfaction with the Product.  The sales force
              will be conversant in the conventional technical language of the
              Product, and shall 

                                       16
*Confidential Treatment has been requested for the marked portion.


              develop sufficient knowledge of the industry and any competitive
              products so as to be able to explain to potential customers the 
              difference between the Product and any such competitive products.
              Training and support provided by the sales force shall be rendered
              in the language or languages customarily employed in countries in 
              the Territory.
  
    9.4. Capital, Facilities and Personnel.  To the extent commercially
         reasonable, B. Braun shall possess sufficient capital, facilities
         (including warehouse facilities) and administrative personnel to
         support B. Braun's obligations to test, label, package, market,
         transport, store, distribute and sell the Product in the Territory.

    9.5. Inventory.  B. Braun shall maintain, subject to availability and
         delivery of Bulk rh[*] from GTC, a sufficient inventory of the Product
         to provide prompt delivery of the Product to its customers in the
         Territory.

    9.6. Books and Records.  For a period of not less than two (2) years, B.
         Braun shall maintain and preserve distinct, complete and accurate
         books of accounts and inventories (including, without limitation, lot
         records) related to all of its activities as a distributor under this
         Agreement, and shall make such books and records available to an
         independent accountant designated by GTC not more than one (1) time
         per year, upon GTC's request and at GTC's cost, for the limited
         purpose of confirming the completeness and accuracy of such books and
         records.

10. Clinical Trials.

   10.1. In the Territory.  B. Braun, at is cost and expense, shall be
         responsible for all Pivotal Clinical Trials and registration
         activities for the Product in the Territory, except for Phase
         I/II clinical trials, which are GTC's responsibility.

   10.2. In [*].  GTC, at is cost and expense, shall be responsible for
         all worldwide Phase I/II clinical trials and clinical development
         and registration activities for the Product in [*].

   10.3. Cost-Sharing upon Exercise of Co-Marketing Option.  Upon exercise
         by B. Braun of the Co-Marketing Option set forth in Section 8,
         above, the Parties will agree upon budgets of [*] Pivotal
         Clinical Trials and the initial regulatory registration of the
         Product in [*].  B. Braun shall pay fifty percent (50%) of the
         costs of such Pivotal Clinical Trials up to a maximum payment by
         B. Braun of [*].  B. Braun shall pay GTC fifty percent (50%) of
         this amount as costs of the Pivotal Clinical Trials are incurred,
         if the initial costs of such Pivotal Clinical Trials are less
         than [*], with the balance due upon completion of such trials and
         analysis of the data therefrom.
 
   10.4. Clinical Data and Regulatory Filings.  Each Party shall make
         available to the other all of its clinical and formulation data
         and regulatory filings free of charge.  The Parties shall discuss
         and coordinate the further exchange of information and data as is
         necessary to obtain and maintain regulatory approval of the
         Product.  Each party shall have a royalty-free, non-exclusive
         license, with the right to sublicense, to use 

                                       17
*Confidential Treatment has been requested for the marked portion.


              all of the data and information furnished under this Section for
              the sole and exclusive purposes of conducting clinical testing 
              and obtaining or maintaining regulatory approval of the Product,
              in the Territory in the case of B. Braun, and in [*] in the case
              of GTC. GTC may share such clinical data and regulatory filings 
              with its [*] designee, under appropriate confidentiality 
              restrictions, for such designee to obtain and maintain regulatory
              approval of the Product in [*].  Each Party agrees, to the extent 
              practical, to provide the other Party with the opportunity to 
              review and comment on all regulatory filings and material 
              correspondence with regulatory agencies.  Each Party shall have 
              the right to attend meetings the other Party has with regulatory 
              authorities which relate to the Product.

11. Licenses and Royalties.

    11.1.     Grant.  Subject to the fulfillment of the terms and conditions of
              this Agreement, GTC grants to B. Braun:

              a.   an exclusive license under the GTC Patent Rights and GTC's
                   interest in the Project Patent Rights; and

              b.   an exclusive license to use the GTC Technology and GTC's 
                   interest in the Project Technology,

              with the right to grant sublicenses (except as provided below), 
              for the sole and exclusive purposes, restricted to the Field, of 
              (i) filling, finishing and labeling Product from Bulk rh[*] 
              supplied by GTC under this Agreement, (ii) conducting Pivotal
              Clinical Trials on the rh[*], and (iii) using, importing and 
              exporting, marketing and selling the Products, in the Territory.
              The license granted pursuant to Section 11.1.a. shall continue in
              effect until the expiration of the last patent licensed to 
              B. Braun hereunder.  The license granted pursuant to 
              Section 11.1.b. shall continue in effect for ten (10) years from
              the date of first commercial sale of a Product within the
              Territory; provided, however, B. Braun shall have a renewable 
              right to extend such license for successive terms by delivery of
              written notice to GTC. 

              In the event B. Braun exercises the Co-Marketing Option set forth
              in Section 8, above, the license set forth in this Section 11.1 
              shall be expanded to include a non-exclusive license under the 
              GTC Patent Rights and Project Patent Rights and a non-exclusive
              license to use the GTC Technology and Project Technology in [*],
              under the terms and conditions set forth above, except that 
              B. Braun shall not be permitted to sublicense such rights to 
              third parties which are not Affiliates in [*].  

    11.2.     Reservation of Rights.  GTC reserves for itself, its Affiliates,
              other corporate partners, sublicensees and third party designees
              the right under the GTC Patent Rights and the GTC Technology and
              its interest in the Project Patent Rights and Project Technology
              to (a) produce Bulk rh[*], (b) conduct clinical trials on such
              Product in [*], and (c) use, import and sell such Products in
              [*].  With respect to GTC's retained rights to market and sell
              Products in [*], GTC's sublicense rights 

                                       18
*Confidential Treatment has been requested for the marked portion.


              shall be limited to the right to license a single entity. 

    11.3.     Conversion to Non-Exclusive Licenses.  In the event that B. Braun
              fails to meet the minimum annual purchase requirements set forth
              in Section 7.2(b), above, after using commercially reasonable
              efforts, GTC shall have as its sole remedy the right, in its sole
              discretion and upon thirty (30) days prior written notice to B.
              Braun, to convert the license set forth in Section 11.1, above,
              from exclusive to non-exclusive; provided, however, B. Braun may,
              at its option, preserve the exclusivity of such license if,
              within said thirty (30) day period, it pays to GTC the balance of
              the annual minimum purchase requirement then due for such
              calendar year.  This provision shall be subject to suspension, as
              determined in good faith by the Liaison Committee,  in the event
              of force majeure or legal or Regulatory Authority prohibition or
              registration schedule delay to sell Product in a country in the
              Territory.  

    11.4.     Exclusivity.  During the term of this Agreement, and for as long
              as the license set forth in Section 11.1, above, has not been
              terminated or converted to non-exclusive, B. Braun and GTC agree
              that each will work exclusively with the other with respect to
              the development, production and manufacture of any recombinant
              human [*], and agree not to develop, produce, manufacture or sell
              (or collaborate or work with any third party to develop,
              manufacture or sell), any form of recombinant human [*] except as
              provided in this Agreement, nor have this done by third parties. 
              Notwithstanding the foregoing, and subject to the other
              provisions of this Agreement, GTC may subcontract to, and work
              and/or collaborate with, third parties with respect to the
              development and manufacture of Transgenic Goats which produce
              rh[*] in their milk, and for the production of such rh[*] from a
              Production Herd only for the purposes of this Agreement.  

    11.5.     GTC Rights in Territory.  In the event that B. Braun elects not
              to file for regulatory approval for a Product in a country in the
              Territory within one (1) year following completion of a Pivotal
              Clinical Trial, or if approval is obtained in a country and B.
              Braun elects within a commercially reasonable period not to
              market and sell a Product in such country, then GTC shall have
              the non-exclusive right itself or through an Affiliate or
              sublicensee to use, import and sell the Product in such country. 

    11.6.     Royalties.  Royalty payments to GTC under this Section 11.6 are
              subject to the existence of one or more valid claims under the
              GTC Patent Rights or Project Patent Rights, or the existence of
              GTC Technology or Project Technology which is not available to
              third parties (other than permitted third parties under this
              Agreement).

              a.   Sales of Products in Territory.  Beginning one (1) year 
                   following commercial launch of the Product, and following 
                   Regulatory Authority approval in a country in the Territory
                   to market and sell Products, B. Braun shall pay to GTC 
                   royalties on Net Sales Price of each Product sold by 
                   B. Braun, its Affiliates and/or sublicensees in such 
                   countries in the Territory, as follows:

                                       19
*Confidential Treatment has been requested for the marked portion.



                        Annual Net Sales                   Percentage
    
              [*]
    
              b.   Sales of Products in [*].  In addition to the foregoing
                   royalties, in the event B. Braun exercises its Co-Marketing
                   Option, B. Braun shall pay to GTC royalties on Net Sales 
                   Price of each Product sold by B. Braun and/or its Affiliates
                   in [*], as follows:

                        Annual Net Sales                   Percentage
    

              [*]

    11.7.     Reports and Payment.  B. Braun shall deliver to GTC, within sixty
              (60) days after the end of each calendar quarter, a written
              report showing its computation of royalties due under this
              Agreement upon Net Sales during such calendar quarter.  All Net
              Sales shall be segmented in each such report according to sales 
              on a country-by-country basis, including the rates of exchange
              used to convert such royalties to United States Dollars from the
              EURO-currency or other currency in which such sales were made 
              (in the case of conversion from the EURO currency, from fixation
              of the exchange rate between the applicable currency to the
              EURO).   Simultaneously with the delivery of each such report, B.
              Braun shall tender payment in United States Dollars of all
              royalties shown to be due therein.  

              In the event the exchange rate of the German Mark (and 
              subsequently the EURO currency) and the United States Dollar 
              increases or decreases from the exchange rate applicable on the 
              Effective Date of this Agreement by more than ten (10) percent, 
              an adjustment in the payment due GTC under this Section 11 shall 
              be made on a payment-by-payment basis, whereby each Party will 
              equally share such increase or decrease.  The basis for 
              determining the exchange rates in effect for the purposes of this
              Section shall be the exchange rate for the average of the "buy 
              and sell" rates as published in the European Edition of the Wall
              Street Journal on the first and last days of the calendar quarter
              for which payment is due.

    11.8.     Foreign Royalties.  Where royalties are due hereunder for sales
              of Products in a country where, by reason of currency regulations
              or taxes of any kind, it is impossible or illegal for B. Braun to
              transfer royalty payments to GTC for Net Sales in that country,
              such royalties shall be deposited in whatever currency is
              allowable by the person or entity not able to make the transfer
              for the benefit or credit of GTC in an accredited bank in that
              country that is reasonably acceptable to GTC.

    11.9.     Taxes.  Any and all income or similar taxes imposed or levied on
              account of the receipt of royalties payable under this Agreement
              which are required to be withheld by B. Braun shall be paid by B.
              Braun on behalf of GTC and shall be paid to the proper taxing
              authority.  Proof of payment shall be secured and sent to GTC by
              B. Braun as evidence of such payment in such form as required by
              the tax authorities having jurisdiction over B. Braun.  Such
              taxes shall be deducted from the royalty that would otherwise be
              remittable by B. Braun.

                                       20
*Confidential Treatment has been requested for the marked portion.


    
    11.10.    Records.  B. Braun shall keep, and shall require all Affiliates
              and any permitted sublicensees to keep, for a period of at least
              two (2) years, full, true and accurate books of accounts and
              other records containing all information and data which may be
              necessary to ascertain and verify the royalties payable
              hereunder.  During the term of this Agreement and for a period of
              two (2) years following its termination, GTC, at its costs, 
              shall have the right from time to time (not to exceed once during
              each calendar year) during normal business hours to have an
              independent agent, accountant or other representative inspect in
              confidence, such books, records and supporting data.

    11.11.    Payment Method.  B. Braun will pay GTC by wire transfer of good
              and immediately available funds to a bank and account, as
              specified in writing by GTC, or by any other means agreed upon by
              the Parties.

12. Representations, Warranties, Indemnities and Insurance.  

    12.1.     Representations and Warranties by GTC.  GTC hereby represents and
              warrants to B. Braun as follows:

              a.   Organization and Good Standing.  GTC is a corporation duly
                   organized, validly existing and in good standing under the 
                   laws of the Commonwealth of Massachusetts and has full 
                   corporate power and authority to conduct its business as 
                   presently conducted and as proposed to be conducted by it 
                   and to enter into and perform this Agreement, and to carry 
                   out its obligations hereunder and the other transactions 
                   contemplated by this Agreement.

              b.   Authority for Agreement.  The execution, delivery and 
                   performance by GTC of this Agreement has been duly 
                   authorized by all necessary corporate action.  The execution
                   and performance of the transactions contemplated by this 
                   Agreement and compliance with its provisions by GTC will not
                   conflict with or result in any breach of any of the terms,
                   conditions or provisions of, or constitute a default under 
                   any indentures lease, agreement or other instrument to which
                   GTC is a party or by which it or any or its properties is 
                   bound, or any decree, judgment, order, statute, rule or 
                   regulation known by GTC to be applicable to it.

              c.   Governmental Consents.  To GTC's knowledge no consent, 
                   approval, order or authorization of, or registration, 
                   qualification, designation, declaration or filing with, any
                   governmental authority is required on the part of GTC in 
                   connection with the execution of this Agreement or the 
                   transactions contemplated by this Agreement.

              d.   No Known Infringement.  Following diligent inquiry, including
                   worldwide  patent searches conducted by outside patent 
                   counsel, GTC is unaware of any infringement of the perfected
                   and valid intellectual property rights of any third party,
                   or any claim of such infringement by any third party, that 
                   would arise 

                                       21



                   upon the immediate use of any gene construct or other 
                   material presently contemplated to be furnished by GTC to
                   B. Braun pursuant to this Agreement, or from the presently
                   contemplated and proposed activities of GTC pursuant to this
                   Agreement, including, without limitation, the production of 
                   Bulk rh[*] and its sale as part of the Product. The Parties
                   acknowledge that the perfected and valid intellectual 
                   property rights of third parties relating to recombinant 
                   human [*] materially vary from country to country (for 
                   example, third party patent rights exist in some countries 
                   but not in others; and such patent rights will expire at 
                   different times in different countries).  Therefore, GTC's 
                   representation and warranty to B. Braun under this 
                   Subsection (d) is applicable as of the Effective Date only 
                   with respect to those countries in which perfected and valid
                   third party intellectual property rights do not exist (for 
                   example, without limitation, in [*]).   GTC will provide 
                   B. Braun with a copy of the report from its outside patent 
                   counsel within fifteen (15) business days following the 
                   Effective Date, confirming GTC's warranty under this 
                   Subsection (d) with respect to patent rights of third 
                   parties.  GTC further represents and warrants to B. Braun 
                   that the relevant intellectual property rights of third 
                   parties which do exist as of the Effective Date should 
                   expire in time for B. Braun to have broad marketing rights
                   for the Product in the Territory, consistent with the 
                   commercialization schedule set forth in this Agreement.

              e.   Production of Bulk rh[*].  GTC represents and warrants to B.
                   Braun that  GTC's production of the Bulk rh[*] shall be 
                   performed in accordance with GTC's standard operating 
                   procedures under the supervision and control of its qualified
                   personnel.  GTC further warrants that the Bulk rh[*] supplied
                   to B. Braun under this Agreement shall meet the 
                   Specifications at the time of delivery, shall not be 
                   adulterated or misbranded within the meaning of the Federal 
                   Food, Drug and Cosmetic Act in effect at the time of 
                   delivery, and shall meet the applicable Regulatory Authority
                   requirements.  

              f.   No Other Licenses.  GTC represents and warrants to B. Braun 
                   that GTC has not granted rights to the GTC Patent Rights or 
                   GTC Technology to third parties for use in the Field in the
                   Territory [*].  GTC further represents and warrants to 
                   B. Braun that, following diligent inquiry, including 
                   worldwide patent searches conducted by outside patent 
                   counsel, GTC is unaware of any infringement of the perfected
                   and valid intellectual property rights of [*], or any claim 
                   of such infringement by [*], which would arise by the 
                   performance of the rights granted to B. Braun under this 
                   Agreement, and GTC will defend, indemnify and hold harmless 
                   B. Braun and its Affiliates, permitted subdistributors,
                   agents, directors, officers and employees, at GTC's cost and
                   expense, from and against any and all losses, costs, 
                   liabilities, damages, fees and expenses, including reasonable
                   attorneys' fees and expenses, incurred in connection with 
                   any claim, action or proceeding brought by [*] and arising 
                   out of or in connection a breach of GTC's representation and
                   warranty contained in this Subsection (f).     

              g.   GTC Patent Rights.  GTC represents and warrants to B. Braun 
                   that the issued 

                                       22

*Confidential Treatment has been requested for the marked portion.




                   patents listed in Schedule B to this Agreement are valid 
                   and effective as of the Effective Date. 

              h.   Exclusivity of Warranty and Limitation of Remedies.  The 
                   warranties made by GTC in this Section 12.1 are in lieu of 
                   all other representations and warranties, express or 
                   implied, including, but not limited to, implied warranties 
                   of merchantability or fitness for a particular purpose. 

    12.2.     Representations and Warranties by B. Braun.  B. Braun hereby
              represents and warrants to GTC as follows:

              a.   Organization.  B. Braun is a German corporation duly 
                   organized and validly existing under the laws of Germany 
                   and has full power and authority to enter into and perform 
                   this Agreement, and to carry out the transactions 
                   contemplated by this Agreement. 

              b.   Authority for Agreement.  The execution, delivery and 
                   performance by B. Braun of this Agreement has been duly 
                   authorized by all necessary corporate action, and has been 
                   duly executed and delivered by B. Braun.  The execution 
                   and performance of the transactions contemplated by this 
                   Agreement and compliance with its provisions by B. Braun 
                   will not conflict with or result in any breach of any of 
                   the terms, conditions or provisions of, or  constitute 
                   default under, any indentures, lease, agreement or other 
                   instrument to which B. Braun is a party or by which it or 
                   any or its properties is bound, or any decree, judgment, 
                   order, statute, rule or regulation known by B. Braun to be 
                   applicable to it. 

              c.   Governmental Consents.  To B. Braun's knowledge, except as 
                   provided herein, no consent, approval, order or 
                   authorization of, or representation, qualification, 
                   designation, declaration, or filing with any governmental 
                   authority is required on the part of B. Braun in 
                   connection with the execution of this Agreement or the 
                   transactions contemplated by this Agreement. 

              d.   No Infringement.  B. Braun is unaware of any infringement 
                   of the perfected and valid rights of any third party, or 
                   any claim of such infringement by any third party, that 
                   would arise upon the use of any gene construct or other 
                   material presently contemplated to be furnished or 
                   obtained by B. Braun pursuant to this Agreement, or from 
                   the contemplated activities of B. Braun pursuant to this 
                   Agreement. 

              e.   Exclusivity of Warranty and Limitation of Remedies.  The 
                   warranties made by B. Braun in this Section 12.2 are in 
                   lieu of all other representations and warranties, express 
                   or implied, including, but not limited to, implied 
                   warranties of merchantability or fitness for a particular 
                   purpose. 

    12.3.     Limitation of Liability.  Unless otherwise specifically provided
              for in this Agreement, neither Party will be liable for any lost
              profits arising out of the such 

                                       23



              Party's performance or non-performance of its obligations under 
              this Agreement, whether any such damages are based on a claim 
              of negligence, strict liability, breach of warranty or 
              otherwise.  Neither Party will be liable for any other 
              indirect, incidental, consequential or special damages arising 
              out of such Party's performance or non-performance of its 
              obligations under this Agreement, whether any such damages are 
              based on a claim of negligence, strict liability, breach of 
              warranty or otherwise; provided, however, a Party may be liable 
              for such other indirect, incidental, consequential or special 
              damages in the event such Party is held to have willfully 
              breached its material obligations under this Agreement or is 
              held to have been negligent in its performance of its 
              obligations hereunder.

    12.4.     Indemnification by B. Braun.  B. Braun agrees to defend,
              indemnify and hold harmless GTC and its Affiliates, agents,
              directors, officers and employees, at B. Braun's cost and
              expense, from and against any and all losses, costs, liabilities,
              damages, fees and expenses, including reasonable attorneys' fees
              and expenses (collectively, "Liabilities") incurred in connection
              with any claim, action or proceeding brought by a third party and
              arising out of or in connection with any and all import testing,
              filling, finishing, labeling, packaging, registration,
              inspection, marketing, sale, distribution or any other activities
              related to the Product which are performed by or on behalf of B.
              Braun, including, but not limited to, any actual or alleged
              injury, damage, death or other consequence occurring to any
              person as a result, directly or indirectly, of the possession,
              consumption or use of the Product, regardless of the form in
              which any such claim is made. 

              B. Braun's obligation to defend and indemnify GTC under this 
              Section 12.4 shall not apply to the extent that the existence 
              or incurrence of any such Liabilities is attributable to the 
              negligence, breach of warranty, recklessness, fault, errors or 
              omissions, misconduct, or otherwise of GTC or its Affiliates, 
              subdistributors, agent, directors, officers and employees.

    12.5.     Indemnification by GTC.  GTC agrees to defend, indemnify and hold
              harmless B. Braun and its Affiliates, permitted subdistributors,
              agents, directors, officers and employees, at GTC's cost and
              expense, from and against any and all Liabilities incurred in
              connection with any claim, action or proceeding brought by a
              third party and arising out of or in connection with any actual
              or alleged injury, damage, death or other consequence occurring
              to any person as a result, directly or indirectly, of a Product
              defect arising from GTC's production of Bulk rh[*], regardless of
              the form in which any such claim is made.

              GTC's obligation to defend and indemnify B. Braun under this 
              Section 12.5 shall not apply to the extent that the existence 
              or incurrence of any such Liabilities is attributable to the 
              negligence, breach of warranty, recklessness, fault, errors or 
              omissions, misconduct, or otherwise of B. Braun or its 
              Affiliates, subdistributors, agent,  directors, officers and 
              employees.

    12.6.     Defense of Claims.  In the event of any such claim against a
              Party or its Affiliates, subdistributors, agents, directors,
              officers or employees, the indemnified Party shall 

                                       24

*Confidential Treatment has been requested for the marked portion.




              promptly notify the indemnifying Party in writing of the claim 
              and the indemnifying Party shall manage and control, at its sole 
              expense, the defense of the claim and its settlement.  The 
              indemnified Party shall cooperate with the indemnifying Party 
              and may, at its option and at its own expense, be represented 
              in any such action or proceeding.  The indemnifying Party shall 
              not be liable for any settlements, litigation costs, or expenses 
              incurred by the indemnified Party without the indemnifying 
              Party's written consent, such consent to be promptly given and 
              not unreasonably withheld.

    12.7.     Liability Insurance.  Each Party shall secure and maintain at its
              own expense during the term of this Agreement an adequate
              insurance policy or policies with an insurer or insurers,
              protecting the Party against any and all risks typically insured
              against by businesses comparable to the Party, including without
              limitation general and products liability, arising or occurring
              upon or in connection with each Party's business.  Such policy or
              policies or program shall include general and products liability
              coverage in an amount typically secured by businesses comparable
              to the Party.  Each Party shall furnish the other Party with
              certificates evidencing all such insurance.

13. Pharmacovigilance Programs.   If either Party receives any complaints 
    (excluding customer service-related complaints) relating to the 
    manufacture and use of Product, including adverse reaction reports, it 
    promptly shall notify the other Party of such complaints and reports; 
    provided, however, that in the case of adverse reaction reports 
    concerning "serious adverse experiences" (as such term, or analogous 
    terms, are defined by the Regulatory Authorities in any country in the 
    Territory, as applicable), such Party immediately shall notify the other 
    Party by telefax and/or telephone of such report, but in no event more 
    than two (2) working days after receipt of such report. Following 
    execution of this Agreement, GTC and B. Braun promptly shall agree upon a 
    written policy for reporting adverse experiences which will comply with 
    all applicable Regulatory Authority requirements.

14. Proprietary Rights.

    14.1.     Ownership.  GTC  shall own for itself all GTC Patent Rights and
              GTC Technology.  The Parties shall jointly own all Project Patent
              Rights and Project Technology.  Either Party is free to use its
              ownership interest in the Project Patent Rights and Project
              Technology outside the scope of this Agreement; provided,
              however, neither Party shall use such ownership interest in
              collaboration with a third party, or license such ownership
              interest to a third party, without notifying the other Party, and
              the other Party may object to such collaboration or license
              within thirty (30) days of notice thereof, if it can be
              reasonably demonstrated that such collaboration or license would
              materially disadvantage such Party's business interests.

    14.2.     Filing and Maintenance of Patents.  

              a.   Project Patent Rights.  The Parties shall cooperate with 
                   respect to decisions whether or not to seek or continue to 
                   seek or maintain patent protection on the Project Patent 
                   Rights in any country in the world, and shall have the 
                   right, jointly in both their names, to file for, procure, 
                   and maintain patents on any 

                                       25


                   such Project Patent Rights in any country in the world, 
                   with the expenses being shared equally by the Parties.  If 
                   one Party elects not to seek or continue to seek or 
                   maintain patent protection on any Project Patent Rights in 
                   any country in the world, the other Party shall have the 
                   right, in its name, to file, procure and maintain in such 
                   countries patents on such Project Patent Rights, with the 
                   expenses being borne by such Party. 

              b.   GTC Patent Rights.  GTC shall have the right and 
                   responsibility to decide whether or not to seek or 
                   continue to seek or maintain patent protection on the GTC 
                   Patent Rights in any country in the world, and shall have 
                   the right to file for, procure, and maintain patents on 
                   any such GTC Patent Rights in any country in the world, 
                   with the expenses being borne by GTC.  If GTC elects not 
                   to seek or continue to seek or maintain patent protection 
                   on any GTC Patent Rights in any country in the world, and 
                   GTC has the right to permit B. Braun to file, procure and 
                   maintain in such countries patents on such GTC Patent 
                   Rights, B. Braun shall have the right, in its name, to 
                   file, procure and maintain in such countries patents on 
                   such GTC Patent Rights, with the expenses being borne by 
                   B. Braun, and the rights under such GTC Patent Rights 
                   thereafter shall be transferred to B. Braun.  GTC agrees 
                   to advise B. Braun of all decisions taken under this 
                   Subsection in a timely manner, but in any case at least 
                   ninety (90) days prior to the time any action is required, 
                   in order to allow B. Braun to protect the Parties' 
                   ownership and license interests in the GTC Patent Rights. 

    14.3.     Patent Cooperation.  Each Party shall provide the other Party
              with copies of all substantive communications from all patent
              offices regarding applications or patents on any Project Patent
              Rights and Project Technology  promptly after the receipt
              thereof.  Each Party shall provide the other Party with copies of
              all proposed substantive communications to such patent offices
              regarding applications or patents on any such Project Patent
              Rights in sufficient time before the due date in order to enable
              the other Party an opportunity to comment on the content thereof. 
              Each Party shall make available to the other Party or its
              authorized attorneys, agents, or representatives, such of its
              employees whom the other Party in its reasonable judgment deems
              necessary in order to assist it in obtaining patent protection
              for the Project Patent Rights.  Each Party shall sign or use its
              best efforts to have signed all legal documents necessary to file
              and prosecute patent applications or to obtain or maintain
              patents at no cost to the other Party.

    14.4.     Infringement.

              a.   Each Party shall promptly report in writing to the other 
                   Party during the term of this Agreement any known (1) 
                   infringement or suspected infringement or (2) unauthorized 
                   use or misappropriation of any of the GTC Patent Rights or 
                   Project Patent Rights in the Territory, and shall provide 
                   the other Party with all available evidence supporting 
                   said infringement, suspected infringement or unauthorized 
                   use or misappropriation. 

                                       26


              b.   GTC Patent Rights.  

                   i.   GTC shall have the sole and exclusive right to 
                        initiate an infringement or other appropriate suit 
                        anywhere in the Territory against any third party who 
                        at any time has infringed or misappropriated, or is 
                        suspected of infringing or misappropriating, any of 
                        the GTC Patent Rights.  GTC shall give B. Braun 
                        sufficient advance notice of its intent to file said 
                        suit and the reasons therefore, and shall provide B. 
                        Braun with an opportunity to make suggestions and 
                        comments regarding such suit.  GTC shall keep B. 
                        Braun promptly informed, and shall from time to time 
                        consult with B. Braun regarding the status of any 
                        such suit.  In the event that GTC decides not to 
                        initiate an infringement or other appropriate suit 
                        pursuant to this Subsection (b)(i), GTC shall 
                        promptly advise B. Braun of its intent not to 
                        initiate such suit; provided, however, GTC shall 
                        bring infringement or other appropriate actions 
                        against third parties against which a credible claim 
                        of infringement or misappropriation may be asserted, 
                        unless GTC can reasonably demonstrate to B. Braun 
                        that the consequences of such action against such 
                        third parties could materially injure GTC's 
                        intellectual property or other business interests.  
                        In any event, upon written request by B. Braun to 
                        make an election, GTC shall elect to file a suit no 
                        later than one hundred twenty (120) days following 
                        such request, and if GTC has failed to initiate suit 
                        within said one hundred twenty (120) day period, B. 
                        Braun shall have the right to the remedies set forth 
                        in Subsection (b)(iii), below. 

                   ii.  GTC shall have the sole and exclusive right to select 
                        counsel for any suit referred to in Subsection 
                        (b)(i), above, and shall, except as provided below, 
                        pay all expenses of the suit, including without 
                        limitation attorneys' fees and court costs. If 
                        necessary or desirable in GTC's sole opinion, B. 
                        Braun or its Affiliates shall join as a party to the 
                        suit but shall be under no obligation to participate 
                        except to the extent that such participation is 
                        required as the result of being a named party to the 
                        suit.  B. Braun shall offer reasonable assistance to 
                        GTC in connection therewith at no charge to GTC 
                        except for reimbursement of reasonable out-of-pocket 
                        expenses, including reasonable attorneys' fees, 
                        incurred in rendering such assistance.  B. Braun 
                        shall have the right to participate and be 
                        represented in any such suit by its own counsel at 
                        its own expense.  If GTC requires B. Braun to join in 
                        such suit, GTC shall defend, indemnify and hold 
                        harmless B. Braun against any claim arising out of 
                        such suit or any claim for injunctive or other 
                        relief. 

                   iii. In the event GTC decides not to initiate a suit or 
                        fails to elect to file a suit within the one hundred 
                        twenty (120) day time period set forth in Subsection 
                        (b)(ii), above, where GTC has the legal right and 
                        standing to bring such suit, and such election has a 
                        material and adverse affect on B. Braun's market 
                        share with respect to sales of the Product in one or 
                        more of the countries in the Territory in which B. 
                        Braun is exercising commercially reasonable and 
                        diligent efforts to distribute and sell the Product, 
                        then B. Braun may be relieved of a percentage of its 
                        annual 

                                       27


                        minimum purchase requirements, with such percentage 
                        being equal to the percentage of B. Braun's 
                        Territory-wide sales of Product which occurred in 
                        such country or countries during the prior annual 
                        sales period. 

              c.   Project Patent Rights.

                   i.   The Parties shall cooperate in electing whether or 
                        not to initiate an infringement or other appropriate 
                        suit against any third party who at any time has 
                        infringed, or is suspected of infringing, any of, or 
                        of  using without proper authorization all or any 
                        portion of, the Project Patent Rights.  Each Party 
                        shall decide, no later than ninety (90) days 
                        following written notice from the other Party of 
                        infringement pursuant to Subsection (a), above, 
                        whether to participate in such infringement or other 
                        appropriate suit. 

                   ii.  The Parties shall have the joint right to select 
                        counsel for any suit referred to in Subsection 
                        (c)(i), above and shall, except as provided below, 
                        jointly pay in equal parts all expenses of the suit, 
                        including without limitation attorneys' fees and 
                        court costs.  Each Party (except as provided below) 
                        shall be entitled to retain fifty percent (50%) of 
                        any damages, royalties, settlement fees, or other 
                        consideration for infringement resulting therefrom. 

                   iii. In the event that one Party elects not to participate 
                        in such infringement or other appropriate suit 
                        pursuant to subsection (c)(ii), above, that Party 
                        shall promptly advise the other Party of its intent 
                        not to participate in such suit, and the other Party 
                        shall have the right, at its own expense, of 
                        initiating an infringement or other appropriate suit 
                        against any third party who at any time has 
                        infringed, or is suspected of infringing, or of using 
                        without proper authorization all or any portion of 
                        such Project Patent Rights.  In exercising its rights 
                        pursuant to this subsection (c)(iii), the 
                        participating Party shall have the sole and exclusive 
                        right to select counsel and shall, except as provided 
                        below, pay all expenses of the suit including without 
                        limitation attorneys' fees and court costs.  The 
                        participating Party shall be entitled to retain any 
                        damages, royalties, settlement fees, or other 
                        consideration which are attributable to infringement 
                        resulting therefrom.  If necessary, the other Party 
                        shall join as a party to the suit but shall be under 
                        no obligation to participate except to the extent  
                        that such participation is required as a result of 
                        being a named party to the suit.  At the 
                        participating Party's request, the other Party shall 
                        offer reasonable assistance to the participating 
                        Party in connection therewith at no charge to the 
                        participating Party  except for reimbursement of 
                        reasonable out-of-pocket expenses incurred in 
                        rendering such assistance.  The participating Party 
                        shall not settle any such suit involving rights of 
                        the other Party in the Project Patent Rights without 
                        obtaining the prior written consent of the other 
                        Party, which consent shall be promptly given and 
                        shall not be unreasonably withheld.

                                       28

  
    14.5.     Claimed Infringement.

              a.   In the event that a third party at any time provides 
                   written notice of a claim to, or brings an action, suit or 
                   proceeding against, either Party or any of their 
                   respective Affiliates, claiming infringement of its patent 
                   rights or unauthorized use or misappropriation of its 
                   know-how, based upon an assertion or claim arising out of 
                   the development, manufacture and/or sale of the Bulk rh[*], 
                   such Party shall promptly notify the other Party of the 
                   claim or the commencement of such action, suit or 
                   proceeding, enclosing a copy of the claim and/or all 
                   papers served.

              b.   GTC shall attempt, at its costs, to resolve the problem 
                   raised by the asserted infringement in one of the 
                   following ways: 

                   i.   obtain a license permitting GTC and B. Braun to make, 
                        have made, use and sell Bulk rh[*] as part of the 
                        Product in the country or countries in question; or 

                   ii.  obtain a written statement from such third party 
                        that: 

                        (1)  no action will be taken against GTC or B. Braun 
                             and their respective Affiliates, sublicensees or 
                             distributors for the manufacture, use or sale of 
                             Bulk rh[*] as part of the Product; or 

                        (2)  the patent or other third party right is not 
                             infringed by the formulation, manufacture, use 
                             or sale of Bulk rh[*] as part of the Product; or 

                        (3)  obtain a holding that the third party patent is 
                             invalid or the third party patent or other right 
                             is unenforeceable or not infringed by a court of 
                             competent jurisdiction from which no appeal has 
                             or can be taken. 


                   In the event that B. Braun has given written notice to GTC 
                   that a third party has claimed or alleged that the 
                   manufacture, use or sale of Bulk rh[*] as part of the 
                   Product constitutes an infringement of its patent or 
                   patents or industrial property rights against B. Braun, 
                   its Affiliates, sublicensees or distributors and GTC does 
                   not undertake, within sixty (60) days of such notice, to 
                   defend and/or settle such claim or allegation as described 
                   above, B. Braun shall have the right to retain the 
                   royalties otherwise payable to GTC under this Agreement 
                   and to use such royalties to pay for or defray the actual 
                   expended costs of defending each such claim or allegation, 
                   including the costs of settling or satisfying said claim 
                   or allegation.  B. Braun shall not settle or satisfy such 
                   claim or allegation in a manner which affects GTC's rights 
                   under the GTC Patent Rights, GTC Technology, Project 
                   Patent Rights or Project Technology without GTC's prior 
                   written consent.  During the defense of such claims or 
                   allegations, B. Braun shall submit documentation showing 
                   royalties accruing to 

                                       29
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                   GTC and the expenses of defending against the claims or 
                   allegations of infringement.  In the event such claim or 
                   allegation is resolved, B. Braun shall promptly return to 
                   GTC any amount of withheld royalties in excess of the 
                   costs expended by B. Braun in resolving such claim or 
                   allegation. 

                   If, under the preceding paragraph, GTC settles or 
                   satisfies such claim or allegation of patent or industrial 
                   property right infringement, then GTC shall be responsible 
                   for any payments to third parties to settle or satisfy 
                   such claim or allegation.  If, under the preceding 
                   paragraph, B. Braun settles or satisfies such claim or 
                   allegation of patent or industrial property right 
                   infringement, then B. Braun shall be entitled to deduct 
                   fifty percent (50%) of those payments or royalties paid to 
                   such third party from the royalties due to GTC under this 
                   Agreement, up to a maximum of fifty percent (50%) of the 
                   royalties otherwise due GTC hereunder. 

15. Confidential Information. 

    15.1.     Treatment of Confidential Information.  Each Party shall maintain
              the Confidential Information of the other Party in confidence,
              and shall not disclose, divulge or otherwise communicate such
              Confidential Information to others, or use it for any purpose,
              except pursuant to, and in order to carry out, the terms and
              objectives of this Agreement, and hereby agrees to exercise every
              reasonable precaution to prevent and restrain the unauthorized
              disclosure of such Confidential Information by any of its
              directors, officers, employees, consultants, subcontractors,
              sublicensees or agents.  The Parties' confidentiality obligations
              shall expire ten (10) years following termination of this
              Agreement.

    15.2.     Release from Restrictions.  The provisions of Section 15.1 shall
              not apply to any Confidential Information disclosed hereunder
              which:

              a.   was known or used by the receiving Party or its Affiliates 
                   prior to its date of disclosure to the receiving Party, as 
                   evidenced by the prior written records of the receiving 
                   Party or its Affiliates; or

              b.   either before or after the date of the disclosure to the 
                   receiving Party is lawfully disclosed without restriction 
                   to the receiving Party or its Affiliates by an 
                   independent, unaffiliated third party rightfully in 
                   possession of the Confidential Information (but only to 
                   the extent of the rights received from such third party); 
                   or 

              c.   either before or after the date of the disclosure to the 
                   receiving Party becomes published or generally known to 
                   the public through no fault or omission on the part of the 
                   receiving Party or its Affiliates; or

              d.   is required to be disclosed by the receiving Party or its 
                   Affiliates to comply with applicable laws, to defend or 
                   prosecute litigation or to comply with governmental 
                   regulations, provided that the receiving Party provides 
                   prior 

                                       30


                   written notice of such disclosure to the other Party and 
                   takes reasonable and lawful actions to avoid and/or 
                   minimize the degree of such disclosure.

    15.3.     Publications.  The following restrictions shall apply with 
              respect to the disclosure in scientific journals or 
              publications by either Party or any employee or consultant of 
              either Party relating to any scientific work relating to the 
              Product and/or Final Product:

              a.   The publishing Party shall provide the other Party with an 
                   advance copy of any proposed publication (which may be in 
                   draft form) relating to the Product/Final Product, and the 
                   other Party shall have a reasonable opportunity to 
                   recommend any changes it reasonably believes are necessary 
                   to preserve patent rights or know-how licensed to or owned 
                   in whole or in part by the other Party, or are otherwise 
                   necessary to promote or protect the interests of the other 
                   Party, and the incorporation of such recommended changes 
                   shall not be unreasonably refused; 

              b.   if the other Party informs the publishing Party, within 
                   thirty (30) days of receipt of an advance copy of a 
                   proposed publication, that such publication in its 
                   reasonable judgment could be expected to have a material 
                   adverse effect on any patent rights or know-how licensed 
                   to or owned in whole or in part by the other Party, the 
                   publishing Party shall, to the extent permitted by its 
                   agreements with its employees and consultants, delay or 
                   prevent such publication as proposed. In the case of 
                   inventions, the delay shall be sufficiently long to permit 
                   the timely preparation and filing of a patent 
                   application(s) or application(s) for a certificate of 
                   invention on the information involved; and

              c.   if the other Party informs the publishing Party, within 
                   thirty (30) days of receipt of an advance copy of a 
                   proposed publication, that such publication in its 
                   reasonable judgement could be expected to have a material 
                   adverse effect on the interests of the other Party, the 
                   Parties shall discuss the publication and, if mutually 
                   agreeable, the publishing Party shall, to the extent 
                   permitted by its agreements with its employees and 
                   consultants, delay or prevent such publication as agreed. 

    15.4.     Permissible Uses of Confidential Information.  The foregoing
              provisions shall not preclude the disclosure of Confidential
              Information as necessary for (a) the Parties' performance of this
              Agreement, (b) the manufacture of Bulk rh[*] by GTC, (c) the
              manufacture and marketing of the Product by B. Braun pursuant to
              this Agreement or (d) B. Braun's filing and prosecution of
              applications with Regulatory Authorities for the manufacture,
              sale and use of the Product in the Territory or the manufacture
              of the Bulk rh[*] by GTC.

16. Termination.

    16.1.     Term. The term of this Agreement (the "Term") will commence on
              the Effective Date and will continue for so long as one or more
              valid claims under the GTC Patent 

                                       31

*Confidential Treatment has been requested for the marked portion.



              Rights or Project Patent Rights, or GTC Technology or Project 
              Technology which is not available to third parties (other than 
              permitted third parties under this Agreement), exists, unless 
              terminated sooner pursuant to the express provisions of this 
              Agreement.

    16.2.     Termination for Breach.  

              a.   General Provision.  Each Party shall be entitled to 
                   terminate this Agreement by written notice to the other 
                   Party in the event that the other Party shall be in 
                   material default of any of its obligations hereunder, and 
                   shall fail to remedy any such default within sixty (60) 
                   days after notice thereof by the non-breaching Party.  Any 
                   such notice shall specifically state that the 
                   non-breaching Party intends to terminate this Agreement in 
                   the event that the breaching Party shall fail to remedy 
                   the default in said period.  Upon termination of this 
                   Agreement pursuant to this Section 16.2, neither Party 
                   shall be relieved of any obligations incurred prior to 
                   such termination. The Parties acknowledge that material 
                   breach by B. Braun or GTC of its obligations hereunder 
                   shall be considered valid grounds for termination under 
                   this Section 16.2. 

              b.   Partial Termination Where B. Braun is the Breaching Party. 
                   Notwithstanding anything contained in this Section 16.2 to 
                   the contrary, if B. Braun is the breaching Party and if B. 
                   Braun's default (a) primarily occurred in or primarily 
                   affects a particular country or group of countries which 
                   are part of the Territory and (b) does not materially 
                   adversely affect (i) B. Braun's ongoing ability to fully 
                   perform its obligations under this Agreement in the other 
                   countries specified in this Agreement or (ii) GTC's 
                   reputation or its ongoing ability to perform its 
                   obligations under this Agreement, then GTC shall have the 
                   right to terminate B. Braun's rights under this Agreement 
                   with respect to the country or group of countries in which 
                   the default occurred or primarily affects.  Upon such 
                   partial termination of B. Braun's rights under this 
                   Agreement pursuant to this Section 16.2, (x) neither Party 
                   shall be relieved of any obligations incurred prior to 
                   such termination or thereafter in the country or countries 
                   specified in this Agreement not subject to such 
                   termination, (y) B. Braun's rights under this Agreement 
                   will terminate in such country or countries according to 
                   the notice, opportunity to cure and other procedures 
                   specified for general termination of this Agreement under 
                   this Section 16 and (z) such rights will revert to GTC. 

              c.   GTC Willful Breach or Gross Negligence.  Notwithstanding 
                   anything contained in this Section 16 to the contrary, if, 
                   following the filing of the first BLA by either of the 
                   Parties under this Agreement, GTC has willfully breached 
                   this Agreement or has been grossly negligent in its 
                   performance of its obligations hereunder, and GTC has not 
                   corrected such breach within three (3) months of B. 
                   Braun's written request (which three (3) month period may 
                   be extended by agreement of the Parties, if GTC is 
                   diligently attempting to correct such breach), then  B. 
                   Braun may, at its sole option and without prejudice to any 
                   other remedy it may have, produce itself or have produced 
                   all or any part 

                                       32




                   of its requirements for Bulk rh[*] for use in the Product, 
                   utilizing the GTC Patent Rights, the Project Patent 
                   Rights, the GTC Technology and the Project Technology.  
                   GTC, at its own cost and expense, promptly shall transfer 
                   to B. Braun the non-exclusive right to use the GTC Patent 
                   Rights, Project Patent Rights, GTC Technology and Project 
                   Technology to make and have made the Bulk rh[*] for use in 
                   the Product.  In addition, GTC, at its own cost and 
                   expense, will provide B. Braun with reasonable production 
                   assistance, so that  B. Braun may use the GTC Patent 
                   Rights, Project Patent Rights, GTC Technology and Project 
                   technology to produce Bulk rh[*] for such purpose.  In the 
                   event B. Braun elects to produce or  have a third party 
                   produce Bulk rh[*] for such purpose, B. Braun shall pay 
                   GTC a fee equal to fifty percent (50%) of the royalty 
                   rates set forth in Section 11.6(b), above, on B. Braun's 
                   sales of Product filled and finished from Bulk rh[*] 
                   produced by B. Braun under this Subsection (c).

    16.3.     Termination by B. Braun.  In addition, B. Braun may terminate
              this Agreement, or its rights and obligations in a country or
              countries under this Agreement, as specified below:

              a.   In the event GTC is acquired by a major competitor of B. 
                   Braun, B. Braun shall be entitled to terminate this 
                   Agreement by giving not less than ninety (90) days prior 
                   written notice to GTC. 

              b.   B. Braun may terminate its rights and obligations under 
                   this Agreement with respect to any country  at any time by 
                   giving not less than ninety (90) days prior written notice 
                   to GTC if, due to any governmental or regulatory action in 
                   such country or countries, B. Braun is unable to market 
                   the Product in such country; in such event, all rights to 
                   manufacture, import, market, sell and use the Product in 
                   such country or countries shall revert to GTC.

              c.   B. Braun may terminate this Agreement at any time by 
                   giving not less than ninety (90) days prior written notice 
                   to GTC if B. Braun determines that it does not desire that 
                   development and/or commercialization of the rh[*] and/or 
                   the Product shall be continued; provided, however, in such 
                   event B. Braun shall pay GTC for all reasonable costs and 
                   obligations incurred by GTC (with the Liaison's 
                   Committee's consent) under this Agreement through the date 
                   of such termination.  Thereafter, all of B. Braun's rights 
                   under this Agreement shall revert to GTC, except that B. 
                   Braun shall retain the rights set forth in Section 14.1, 
                   above. 

              d.   B. Braun may terminate this Agreement by giving not less 
                   than ninety (90) days prior written notice to GTC  if a 
                   development milestone as set forth in Section 4.7 and 
                   Schedule C of this Agreement is not met within ninety (90) 
                   days of the date specified for completion of such 
                   milestone; B. Braun also may terminate its rights and 
                   obligations with respect to [*] only, by giving not less 
                   than ninety (90) days prior written notice to GTC, if a 
                   development milestone as set forth in Section 8.3 and 
                   Schedule C of this Agreement is not met within one ninety 

                                       33
*Confidential Treatment has been requested for the marked portion.



                   (90) days of the date specified for completion of such 
                   milestone; provided, however, GTC shall have the 
                   opportunity during such ninety-day notice period to meet 
                   such milestone, in which case this Agreement may not be 
                   terminated.  In the event of termination by B. Braun under 
                   his Subsection (d), B. Braun shall pay GTC for all 
                   reasonable costs and obligations incurred by GTC with the 
                   Liaison Committee's consent) under this Agreement through 
                   the date of such termination. 

    16.4.     Termination by Either Party.  Either Party may terminate this
              Agreement in the event the other Party shall enter into
              liquidation or become insolvent or have a receiver appointed with
              respect to any of its assets or takes or suffers any other
              similar or equivalent action by reason of insolvency or in
              consequence of debt, such termination to be effective immediately
              upon written notice to such other Party.

    16.5.     Effect of Termination.  

              a.   In the event B. Braun terminates this Agreement, other 
                   than pursuant to breach by GTC under Section 16.2 or for 
                   the reasons set forth in Sections 16.3(a) or (d) or 16.4, 
                   above, then for a period of four (4) years following such 
                   termination, B. Braun shall first offer GTC the 
                   opportunity to supply B. Braun with all if its 
                   requirements, if any, of  bulk-form recombinant human [*] 
                   (or any modification or formulation thereof), on 
                   commercially reasonable and competitive terms and 
                   conditions to be agreed to by the Parties.

              b.   Termination of this Agreement shall not affect the rights 
                   and obligations of the Parties accrued under this 
                   Agreement prior to such termination and, other than as 
                   specified in Section 16.3, B. Braun shall be obligated to 
                   make milestone payments under Sections 4.7 and 8.3 in the 
                   event of completion of such milestones prior to 
                   termination of the Agreement. 

              c.   B. Braun shall have the right to sell its remaining 
                   inventory of Product under the obligation to pay to GTC 
                   the running royalties due thereon.

              d.   In the event GTC terminates this Agreement as provided for 
                   herein or Braun terminates this Agreement other than 
                   pursuant to Sections 16.2, 16.3(d) or 16.4, above, or 
                   terminates its rights and obligations with respect to any 
                   country or countries under this Agreement, B. Braun shall 
                   cancel all rights of regulatory approvals with the health 
                   authorities for the Product, if any, in the Territory or 
                   in such country or countries, as applicable, or upon GTC's 
                   request, transfer the same to GTC or an entity to be named 
                   by GTC, with the costs of such transfer being borne by 
                   GTC. 

              e.   Following termination, each Party shall be free to 
                   non-exclusively use its interest in the Project Patent 
                   Rights and Project Technology without restriction or 
                   obligation to the other Party; provided, however, the 
                   restrictions set forth in Section 14.1 shall be applicable 
                   analogously (other than in the event of termination 
                   pursuant to Sections 16.2, 16.3(d) or 16.4, above) and 
                   shall survive 

                                       34

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                   any such termination, as provided for therein.

    16.6.     Survival of Obligations; Return of Confidential Information. 
              Notwithstanding any termination or expiration of this Agreement,
              the obligations of the Parties under Sections 6.2, 12, 14, 15, 16
              and 17 of this Agreement shall survive and continue to be
              enforceable.  Upon any termination of this Agreement, each Party
              shall promptly return to the other Party all written Confidential
              Information, and all copies thereof, of the other Party, but may
              retain one (1) copy for archival purposes.

17. Miscellaneous.

    17.1.     Public Announcements.  Neither Party shall make any public
              disclosure regarding this Agreement without the prior written
              consent of the other Party.  Each Party hereby covenants and
              agrees to collaborate with the other Party within reason
              concerning disclosures which are or may be expected to be
              publicly disseminated regarding the existence of this Agreement. 
              Notwithstanding the foregoing, neither Party shall be required to
              obtain the consent of the other Party regarding a disclosure of
              this Agreement for purposes of disclosures which such Party
              reasonably believes to be required by law; provided, however,
              that the Party intending to disclose such Confidential
              Information provides advance written notice to the other Party,
              and that such disclosing party takes all reasonable and lawful
              actions to obtain confidential treatment for such disclosure and,
              if possible, to minimize the extent of such disclosure.

    17.2.     Good Faith Effort to Resolve Disputes.  Any controversy or claim
              arising out of, or relating to, any provisions of this Agreement,
              or breach thereto, shall be referred for resolution to GTC's
              president, and to B. Braun's president ("Vorstandsvorsitzender"). 
              If the Parties respective officers, or their designees cannot
              reach a resolution of the dispute within sixty (60) days after
              referring such dispute to the Parties respective presidents, then
              the dispute shall be resolved by binding arbitration pursuant to
              the provisions of Section 17.3.

    17.3.     Arbitration.  Any dispute arising between the Parties in
              connection with this Agreement which cannot be resolved pursuant
              to the provisions of Section 17.2 shall be finally settled under
              the rules of the International Chamber of Commerce ("ICC"), by a
              panel of three (3) arbitrators, one of such arbitrators to be
              selected by GTC, one of such arbitrators to be selected by B.
              Braun, and a third to be selected by the other two.  Both legal
              and equitable remedies shall be available to the arbitrators. 
              Judgment upon the award rendered by the arbitrators may be
              entered in any court having jurisdiction thereof.  Any such
              arbitration shall be held in Boston, Massachusetts, for
              arbitration proceedings commenced by B. Braun, and in
              Frankfurt/Main, Germany, for arbitration proceedings commenced by
              GTC, or at such other location as the Parties may agree, and
              shall be conducted in the English language.  The losing Party
              shall bear all costs of the arbitration.  If one Party fails to
              select an arbitrator within sixty (30) days after receiving
              notice of arbitration from the other Party, then such Party shall
              forfeit its right to select an arbitrator, and such arbitrator
              shall be selected by the ICC.

                                       35


    17.4.     Successors and Assigns.  The provisions of this Agreement shall
              be binding upon, and inure to the benefit of, the respective
              successors and assigns of the Parties hereto.

    17.5.     Notices.  Any notice or other communication in connection with
              this Agreement must be in writing and if by mail, by registered
              mail, return receipt requested, and if transmitted by telecopier,
              with a copy sent by mail in accordance with this Section 17.5,
              and shall be effective when delivered to the addressee at the
              address or telecopier number listed below or such other address
              or telecopier number as the addressee shall have specified in a
              notice actually received by the addressor.

              If to B. Braun:     B. Braun Melsungen AG
                                  Carl-Braun-Strasse 1
                                  34212 Melsungen / Germany     
                                  Telecopier: 49/5661/71-3569
                                  Attn: Head of the Pharma Division
  
              If to GTC:          Genzyme Transgenics Corporation
                                  Five Mountain Road
                                  Framingham, Massachusetts 01701 USA
                                  Telecopier: 508-370-3797
                                  Attn: Vice President and General Counsel

    17.6.     Export.  The Parties acknowledge that the export of technical
              data, materials or products may be subject to the exporting Party
              receiving the necessary export licenses.  The Parties agree that
              regardless of any disclosure made by the Parties receiving an
              export of an ultimate destination of any technical data,
              materials or products, the receiving Party will not reexport
              either directly or indirectly, any technical data, material or
              products without first obtaining the applicable validated or
              general license from the United States Department of Commerce,
              United States Food and Drug Administration and/or any other
              agency or department of the United States Government, as
              required.  The receiving Party shall provide the exporting Party
              with any information, certifications or other documents which may
              be reasonably required in connection with such exports under the
              Export Administration Act of 1979, as amended, its rules and
              regulations, the Federal Food, Drug and Cosmetic Act and other
              applicable export laws.

    17.7.     Foreign Corrupt Practices Prohibited.   In carrying out its
              responsibilities under this Agreement, B. Braun will not pay or
              agree to pay, directly or indirectly, any funds or anything of
              value to any public official in a foreign country or jurisdiction
              within the Territory for the purpose of influencing such
              official's official acts or decisions.  If B. Braun directly or
              indirectly offers, pays, promises, gives or authorizes payment of
              any money or anything of value to any government or public
              official for the purpose of influencing any official in the
              course of carrying out this Agreement, this Agreement will
              automatically terminate.  B. Braun agrees to notify GTC of any
              request that B. Braun receives to take any action that might
              constitute a violation of the United States Foreign Corrupt
              Practices Act of 1977, as amended.

                                       36


    17.8.     Entire Agreement.  This Agreement embodies the entire agreement
              and understanding between the Parties with respect to the subject
              matter hereof and supersedes all prior agreements and
              understandings relating to such subject matter. 

    17.9.     Waiver.  Except as otherwise expressly set forth in this
              Agreement, any term of this Agreement may be amended and the
              observance of any term of this Agreement may be waived (either
              generally or in a particular instance and either retroactively or
              prospectively), only with the written consent of the Parties.  No
              waivers or exceptions to any term, condition or provision of this
              Agreement, in any one or more instances, shall be deemed to be,
              or construed as, a further or continuing waiver of any such term,
              condition or provision. 

    17.10.    Counterparts.  This Agreement may be executed in several
              counterparts, each of which shall be deemed an original, but all
              of which together shall constitute one and the same instrument. 

    17.11.    Headings.  The headings of the sections, subsections, and
              paragraphs of this Agreement have been added for convenience only
              and shall not be deemed to be a part of this Agreement. 

    17.12.    Force Majeure.  Either Party's failure to perform any term or
              provision of this Agreement shall be considered an "Excused
              Failure" if caused by any reason beyond its reasonable control
              (not including, however, financial difficulties), or by reason of
              any of the following circumstances: the development of rh[*] or
              the manufacture or marketing of the Product is disallowed or
              restrained by any statute, rule or regulation or a binding
              judgment, order or decree of any court or administrative agency,
              or denial of a necessary governmental approval; and to the extent
              that any one or more of the following conditions actually disable
              the development of rh[*] or the manufacture or marketing of the
              Product, labor disturbances or labor disputes of any kind;
              accident; disease; failure of utilities, mechanical breakdowns,
              material shortages or other similar occurrences; civil disorders
              or commotions, acts of aggression, vandalism or other similar
              occurrences; or fire, floods, earthquakes, or acts of God. 
              Neither Party shall be responsible in damages or otherwise for
              any delay in the performance of its obligations hereunder (other
              than obligations to pay money) caused by any even or occurrence
              considered an Excused Failure; and each Party agrees to give
              notice of each such delay to the other Party within ten (10)
              business days of its inception, together with an estimate of the
              length of the delay, and agrees to continue to make all
              reasonable efforts to perform its obligations hereunder both
              during and after the period of such delay.

    17.13.    Severability.  In the event that any provision of this Agreement
              is held by a court of competent jurisdiction to be unenforceable
              because it is invalid or in conflict with any law of any relevant
              jurisdiction, such provision shall be deemed not to have taken
              effect from the date of this Agreement and the validity of the
              remaining provisions shall not be affected, and the rights and
              obligations of the Parties shall be construed and enforced as if
              the Agreement 

                                       37

*Confidential Treatment has been requested for the marked portion.



              did not contain the particular provision held to be
              unenforceable, and the Parties shall negotiate in good faith with
              each other and with such court with a view to modifying this
              Agreement in a manner which as closely as is reasonably
              practicable reflects the commercial objectives and effect of this
              Agreement as originally signed.
    
    17.14.    Assignment.  Neither this Agreement nor any of the rights or
              obligations hereunder may be assigned or transferred, in whole or
              in part, by either Party, without the prior written consent of
              the other Party, except that (a) either Party may assign this
              Agreement in whole or in part to an Affiliate, provided that such
              Party remains primarily liable and/or responsible for the
              performance of such obligations, and provided further that such
              Affiliate agrees to be bound to the terms and conditions of this
              Agreement, (b) either Party may assign and transfer this
              Agreement in connection with the merger, consolidation or sale of
              all or substantially all of that Party's assets (other than by
              GTC to a major competitor of B. Braun, as provided in Section
              16.3(a)), (c) B. Braun may assign this Agreement, without GTC's
              prior consent, in the event GTC is acquired by a third party
              which is not an Affiliate and (d)  B. Braun may assign this
              Agreement, with GTC's prior consent, following approval of a BLA
              for the Product in a country in the Territory.
 
    17.15.    Governing Law.  This Agreement shall be exclusively governed by
              and construed in accordance with the Laws of Switzerland, without
              regard to conflicts of laws principles dictating the application
              of the law of another jurisdiction.  The Parties expressly reject
              any application of the United Nations Convention on Contracts for
              the International Sale of Goods.

    17.16.    Waiver of Immunity.  To the extent that either Party may in any
              jurisdiction in which proceedings may at any time be taken for
              the enforcement of this Agreement claim for itself or its assets
              immunity from suit, judgment, execution, attachment (whether in
              aid of execution, before judgment or otherwise) or other legal
              process, the Parties hereby irrevocably waive any such immunity
              to the fullest extent now or hereafter permitted by the law of
              such jurisdiction.

    17.17.    Equitable Remedies.  Each Party acknowledges that in certain
              cases (as determined by the courts of competent jurisdiction) of
              a violation by either Party of any of the provisions of this
              Agreement may entitle the other Party to equitable relief in
              addition to any other right or remedy, and this relief shall be
              available in addition to, and shall not be unavailable by reason
              of, the arbitration provisions of Section 17.3 hereof.  Such
              equitable relief may be in the way of temporary restraining
              orders, and preliminary and permanent injunctions, and such other
              equitable relief as any court of competent jurisdiction may deem
              just and proper.
    
    17.18.    Consents Not Unreasonably Withheld.  Whenever a provision is made
              in this Agreement which requires either Party to secure the
              consent or approval of the other, such consent or approval shall
              not be unreasonably withheld, and whenever in this Agreement
              provisions allow for one Party to object or to disapprove a
              matter, such 

                                       38


              objection or disapproval shall not be unreasonably exercised.

    17.19.    Compliance with Laws.  The Parties shall comply with all material
              laws, regulations and other requirements with regard to the
              performance of its obligations under this Agreement.  If any law
              or regulation in the Territory or any subdivision thereof
              requires that any governmental agency receive notice of or
              registration of this Agreement, B. Braun and GTC shall cooperate
              in the preparation of such registration or notification.

    Duly authorized representatives of the parties have signed this Agreement
as of the Effective Date.

GENZYME TRANSGENICS CORPORATION



By  /s/ James A. Geraghty              By  /s/ Michael Young
    ------------------------------         ------------------------------

Print Name: James A. Geraghty          Print Name: Michael Young

Title  President and CEO               Title  Vice President
       ---------------------------            ---------------------------
      duly authorized                       duly authorized


B BRAUN MELSUNGEN AG



By  /s/ Wolfgang Feller                By  /s/ Klaus Hofer
    ------------------------------         ------------------------------

Print Name Wolfgang Feller             Print Name: Klaus Hofer

Title  Member of the Board             Title:  Member of the Board
       ---------------------------            ---------------------------
      duly authorized                         duly authorized


Enclosures

                                       39


                                   Schedule A
                                 Specifications

The Specifications for Bulk rh[*] will be developed and attached to this 
Agreement as an integral part thereof by the Parties, via the Liaison 
Committee. Preliminary Specifications will be established and agreed upon by 
the Liaison Committee within ninety (90) days of the Effective Date.  
Additionally, a detailed development plan will be established and adopted by 
the Liaison Committee within such 90-day period.  The Specifications shall 
include the Acceptance Assays  and related information, as set forth in the 
Agreement.  The parameters of the Specifications shall include, without 
limitation, specifications for Bulk rh[*] purity, activity, amino acid 
sequence information, that the Bulk rh[*] (and Product filled and finished 
therefrom) shall be essentially similar to the leading non-transgenic 
recombinant human [*] produced in cell culture as of the Effective Date of 
this Agreement, anticipated dosing information, the profile of the leading 
non-transgenic recombinant human [*]produced in cell culture as of the 
Effective Date of this Agreement which has been accepted by Regulatory 
Authorities, product quality appropriate for its use in the intended 
indications, quality control provisions, cost parameters, and any other 
parameters agreed to by the Parties. 

                                       40
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                                   Schedule B
                               GTC Patent Rights
                                           
[*] 




                                       41

*Confidential Treatment has been requested for the marked portion.


                                   Schedule C
                              GTC Development Plan
                                           
[*]




                                       42
*Confidential Treatment has been requested for the marked portion.