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                                                                  EXHIBIT 10.16

                   ------------------------------------------
                       MANUFACTURING AND SUPPLY AGREEMENT


                              COC AB FAB'2 SOLUTION
                   ------------------------------------------

This Agreement is entered into as of 08 June 1999 by and between

-    PASTEUR MERIEUX SERUMS & VACCINS, a PASTEUR MERIEUX CONNAUGHT company,
     SOCIETE ANONYME, existing and organized under the laws of the Republic of
     France, having its registered head office at 58, avenue Leclerc, 69007,
     LYON, FRANCE, which capital is 1.698.859.000 FRF, which registered number
     in LYON is B 349 505 370

     Represented by Mr. Michel GRECO, acting as Directeur General.

     (hereinafter referred to as "PMC")

                                                              OF THE FIRST PART,

AND :

-    DRUG ABUSE SCIENCES SA a corporation existing and organized under the laws
     of France having its registered head office at, 2 rue de Crucy, 44000
     Nantes, France.

     Represented by Mrs Maryvonne HIANCE, President,

And

-    DRUG ABUSE SCIENCES INC a corporation existing and organized under the laws
     of the United States its registered head office at 1430 O'Brien Drive,
     Suite E, Menlo Park CA 94025,

     Represented by Mr Stanley Kaplan, its Chief Executive Officer,

     (hereinafter collectively referred to as "DAS")

                                                             OF THE SECOND PART,
<PAGE>

          CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED
          AND FILED SEPARATELY WITH THE COMMISSION. CONFIDENTIAL TREATMENT
          HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS.


                                   WITNESSETH

                  WHEREAS, DAS is a specialty pharmaceutical company dedicated
to drug addiction care applying a disease approach to the treatment of
substance abuse.

                  WHEREAS, PASTEUR MERIEUX Serums & Vaccins is a leading
manufacturer of human vaccines and other related immunological products for
prevention, treatment and cure of diseases in human beings and has extensive
world-wide research, development, manufacturing and marketing operations in
that field and has developed a certain know-how in the Fab'2 technology.

                  WHEREAS, DAS has approached PMC in to manufacture and supply
for DAS a product manufactured according to the Fab'2 technology.

                  NOW, THEREFORE, the parties hereto agree as follows:

                                    ARTICLE 1

                                   DEFINITIONS

                  1.1 "ADDITIONAL EQUIPMENT" shall mean any and all equipment,
other than the Equipment required for the manufacturing of the Equine Plasma
which shall be purchased by PMC pursuant to an Approved Proposal contemplated
in Article 11 herein.

                  1.2 "ADDITIONAL EQUIPMENT COSTS" shall mean the cost of
Additional Equipment.

                  1.3 "COMMERCIAL PERIOD" shall mean the period beginning on
the date of First Commercial Sale and continuing throughout the term of this
Agreement.

                  1.4 "IDAS CERTIFICATE" shall mean the certificate
accompanying the Immunogen provided by DAS to PMC pursuant to Article 3.3 of
this Agreement. A model of a DAS Certificate is attached to this Agreement as
Exhibit 4.

                  1.5 "IDAS PRODUCT" shall mean the COC ab produced by DAS.

                  1.6 "IDAS SPECIFICATIONS" shall mean the specifications
relating to the production of the PMC Product for use as an active ingredient
in the DAS Product, as more particularly described in Exhibit 3 hereto, which
are the sole and exclusive property of DAS.

                  1.7 "DEVELOPMENT PERIOD" shall mean the period beginning on
the Effective Date and ending on the date of First Commercial Sale of the DAS
Product, which period includes the preclinical and clinical phases.

                  1.8 "EFFECTIVE DATE" shall mean the date of execution of this
Agreement.

                  1.9 "EQUIPMENT" shall mean any and all equipment located at
the PMC Facilities and required for the manufacturing of the Equine Plasma at
the Effective Date.

                  1.10 "FIRST COMMERCIAL SALE" shall mean the first sale of a
DAS Product, after obtaining the regulatory approvals necessary to commercially
market (whether under Biological License Application or an the orphan drug
status) such DAS Product by DAS to third-parties, in each case for use or
consumption of such DAS Product by the general public.

                  1.11 "IMMUNOGEN" shall mean the [********]

                  1.12 "LABORATORY" shall mean the laboratory jointly by the
parties to resolve a Product quality dispute as described in Article 13
hereunder and the name of which is mentioned in Exhibit 7 hereto.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       1

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                  1.13 "MANUFACTURING ORDER" shall mean an order for PMC
Product placed by DAS, a model of which is attached as Exhibit 6 of this
Agreement.

                  1.14     "PARTY" shall mean PMC or DAS.

                  1.15 "PMC PRODUCT" shall mean [********]

                  1.16 "PMC FACILITIES" shall mean, as applicable, the facility
in which the PMC Product is manufactured, purified, stored and at which quality
control procedures are effected. The names and addresses of the PMC Facilities
are specified in Exhibit 1 hereto.

                  1.17 "PMC SOP" shall mean the procedures describing (or
otherwise called in French "CAHIER DES CHARGES") the manufacturing and testing
of the PMC Product and set forth in Exhibit 3 hereto which are PMC's sole and
exclusive property

                  1.18 "PMC CERTIFICATE" shall mean the certificate issued by
PMC at delivery of the PMC Product. A model of a PMC Certificate is attached to
this Agreement as Exhibit 5.

                  1.19 "PROTOCOL" shall mean the Protocol relating to the COC
ab Protocol mutually agreed upon between the parties required for the
manufacturing of the PMC Product and attached hereto as Exhibit 2.

                  1.20 "REGULATORY AUTHORITY" shall mean (i) with respect to
the United States, the United States Food and Drug Administration or such other
agency or instrumentality of the United States to which the responsibilities
and authority of the FDA are given or delegated from time to time, (ii) with
respect to France, the Agence du Medicament, or such other agency or
instrumentality of France to which the responsibilities and authority of the
Agence du Medicament are given or delegated from time to time, (iii) with
respect to the European Union, the Agence Europeenne du Medicament and (iv)
with respect to each other jurisdiction, the agencies or instrumentalities of
such jurisdiction having substantially the same responsibilities and authority
of the Agence du Medicament.

                                    ARTICLE 2

                            PURPOSE OF THE AGREEMENT

                  Subject to the terms and conditions set forth in this
Agreement, DAS hereby appoints PMC, who accepts, as an exclusive manufacturer
and supplier of the PMC Product according to the Protocol, DAS Specifications
and PMC SOPs. [***].

                                    ARTICLE 3

                     MANUFACTURING AND SUPPLY OF PMC PRODUCT

                  3.1 DESCRIPTION OF PMC PRODUCT. Subject to the terms and
conditions of this Agreement and in particular, capacity limitation set forth
in the last sentence of Article 4.4, PMC agrees to manufacture and supply to
DAS, who accepts to purchase, subject to the terms and conditions of this
Agreement, exclusively from PMC, the PMC Product that is produced as bulk
active ingredient and in compliance with the Manufacturing Orders placed by DAS
in accordance with this Agreement.

                  The manufacturing, packaging and labeling of the PMC Product
shall be in accordance with DAS Specifications.

                  3.2 RESTRICTIONS. PMC agrees to manufacture and supply the
PMC Product (and any other anti-cocaine immunoglobulin derivatives) [***].

                  3.3 TRANSFER OF IMMUNOGEN. DAS agrees to provide free of
charge to PMC the Immunogen in reasonable sufficient quantities for PMC to
manufacture quantities of PMC Product according to the annual forecast

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       2
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by DAS. PMC shall not be held liable by DAS in the event the Immunogen is not
provided to PMC in the required quantities and timelines. Each quantity of
Immunogen shall be delivered to PMC with a DAS Certificate without which PMC
shall not process such quantity Immunogen. DAS shall advise PMC in advance in a
timely manner of any planned change or modification of the manufacturing
process of the Immunogen, in order to permit PMC to assess the impact, if any,
on the manufacturing of the PMC Product and PMC shall not be held liable in the
event of a change or modification of the process of the Immunogen.

                  At the beginning of each calendar year, PMC shall provide DAS
with a non-binding immunization schedule which shall be coherent with the
non-binding forecast in order to permit DAS to prepare the Immunogen in
sufficient amounts to insure its availability during this Agreement. DAS shall
promptly inform PMC of any event or problem which could have an impact on the
preparation by DAS of the Immunogen.

                  PMC agrees to use the Immunogen only for the purpose of
manufacturing PMC Product on behalf of DAS.

                  3.4 PMC FACILITIES. PMC Product shall be manufactured in the
PMC Facilities unless otherwise mutually agreed by the parties in advance in
writing.

                  For the purposes of manufacturing PMC Product for use in the
DAS Product, PMC shall maintain the PMC Facilities in compliance with
requirements of applicable Regulatory Authority. In the event that the
applicable Regulatory Authorities require any modifications to the PMC
Facilities for such purposes, PMC shall use all diligent efforts to make such
modifications as soon as possible in accordance with Article 12 hereunder.

                  3.5 PMC SOPS. The PMC SOPs listed in Exhibit 3 are PMC's sole
and entire property and can be updated or amended by PMC at any moment provided
that if such update or amendment (i) does not affect production or distribution
of the DAS Product, then PMC shall notify DAS in advance with thirty-days prior
notice, (ii) could affect the production or distribution of the DAS Product and
such change is not mandated by a Regulatory Authority, then PMC shall obtain
DAS's prior written consent, and (iii) could affect the production or
distribution of the DAS Product and such change is mandated by a Regulatory
Authority, PMC shall inform DAS as soon as possible and the parties shall work
in good faith to affect such change in a manner that least disrupts production
or distribution of the DAS Product.

                                    ARTICLE 4

                       FORECASTS AND MANUFACTURING ORDERS

                  4.1      FORECASTS.

                           4.1.1 FORECAST DURING DEVELOPMENT PERIOD: The
Parties have agreed upon a forecast of DAS expected requirements of the PMC
Product during the Development Period attached hereto as Exhibit 8. In the
event that DAS reasonably believes that the Development Period may exceed the
period set forth in Exhibit 8, or that it may require during the Development
Period quantities of PMC Product in excess of those set forth in Exhibit 8, it
shall advise PMC in writing and the parties shall update the forecast to
include such increased [***] days after receipt of such notice by PMC. Should
the increase of total quantities of PMC Product [***] of the amount mentioned
in the forecast, the parties shall discuss in good faith the planning of
delivery of such PMC Products in excess.

                           4.1.2 FORECAST DURING COMMERCIAL PERIOD: During the
year preceding the expected launch of the DAS Product, DAS shall provide within
reasonable time a non-binding forecast of the quantities of PMC Product to be
manufactured on a [***]. This forecast shall be updated by DAS at each year
end, for the following Year 2 and 3, it being understood that all the forecasts
provided by DAS shall be non binding. Within a reasonable period of time
thereafter, PMC shall provide DAS with its proposed immunization schedule for
such period. This non-binding immunization schedule shall be updated by PMC at
each year end, and at such times as DAS's forecasts are adjusted, for the
following two years.

                  4.2      MANUFACTURING ORDER. At each year end, the parties
shall meet in order to discuss the imminent Manufacturing Orders, immunization
schedule and non-binding forecast modification for the following two years. DAS
shall at least [***] before the date upon which it desires that any shipment of
PMC Product be delivered to it, place a Manufacturing Order in writing with
respect to such shipment. All Manufacturing Orders shall be binding on the
parties when received by PMC.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       3

<PAGE>

                  More precisely, DAS shall provide PMC with a Manufacturing
Order for the immunization of horses and the transformation of the equine
plasma within the following dates:

                  (I)      In January of each year, DAS shall provide its
                           Manufacturing Orders for delivery of PMC Product
                           during the third calendar quarter of such year;

                  (II)     In April of each year, DAS shall provide its
                           Manufacturing Orders for deliver, of PMC Product
                           during the fourth calendar quarter of such year,

                  (III)    In July of each year, DAS shall provide its
                           Manufacturing Orders for delivery of PMC Product
                           during the first calendar quarter of the next year;
                           and

                  (IV)     In October of each year, DAS shall provide its
                           Manufacturing Orders for delivery of PMC Product
                           during the second calendar quarter of the next year

                  The models of a Manufacturing Order attached in Exhibit 6
cannot be amended by either party unless mutually agreed between the parties.

                  4.3 INCREASE OF NON-BINDING FORECAST. PMC shall use
commercially reasonable efforts but have no obligation to supply quantities of
PMC Product for Manufacturing Orders that exceed in the second year after [***]
of the aggregate quantities ordered under Manufacturing Orders from the
previous calendar year, and [***] of the aggregate quantities ordered under
Manufacturing Orders from the previous calendar year. In any case, in the event
of [***]amount (as applicable) ordered in the prior year, PMC shall have a [***]
 . Notwithstanding the foregoing, the parties acknowledge and agree that the
maximum capacity of PMC Facilities of the production of PMC Product is limited
to the greater of [***].

                  4.4 FORECASTS AND MANUFACTURING ORDERS IN EXCESS OF CAPACITY.
In the event that Manufacturing Orders or forecasts are likely to require more
than the number of Batches or quantity of PMC Product per year described in
Section 4.3 above, then the Parties shall meet and confer in good faith in
order to discuss an increase capacity at the PMC Facilities, or if such an
increase is not feasible both technically and financially to PMC and DAS, (i)
increase capacity at the PMC Facilities, or if such an increase is not feasible
both technically and financially to PMC and DAS, (ii) use commercially
reasonable efforts to assist DAS to obtain a second source, and PMC shall use
reasonable efforts to assist DAS to implement such second source (including
transfer of the PMC SOPs for use by such second source) to manufacture PMC
Product.

                                    ARTICLE 5

                       TIMELY MANUFACTURING OF PMC PRODUCT

                  PMC undertakes to use all diligent efforts to manufacture and
supply DAS with PMC Product in a timely manner, and in full accordance with the
Manufacturing Orders and this Agreement. For information purposes, a non
binding guideline on the time period for the manufacturing of the PMC Product
is specified in Exhibit 9 hereto.

                                    ARTICLE 6

                             SHIPPING AND RECEPTION

                          ACCEPTANCE OF THE PMC PRODUCT

                  6.1 SHIPPING. PMC shall deliver the PMC Product to DAS ex
works at PMC's Facilities at Marcy L'Etoile (France). DAS shall be in charge of
the transportation and insurance of the PMC Product upon delivery of the PMC
Product to DAS.

                  6.2 DEFECTIVE SHIPMENTS; REMEDIES. In the event that any PMC
Product supplied by PMC fails to conform to the Protocol at delivery, the
parties shall meet and PMC shall at DAS's option either use its best efforts to
replace it as promptly as possible, taking into account the time required to
manufacture quantities of PMC Product, or issue a refund therefor. In the event
that the parties cannot mutually agree on the fact that the PMC Product fails
to perform the Protocol, then the parties shall refer to the quality dispute
procedure described in Article 13 of this Agreement.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       4

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                           6.2.1 PRODUCTION RECORDS. PMC agrees to maintain
records in accordance with the applicable rules and regulations relative to the
PMC Facilities, materials used in the PMC Product and batch processing thereof
for a period of not less than five (5) years after the date of manufacture of
the applicable batch of the PMC Product. Upon DAS's request with a seven (7)
business days notice and at DAS's expense, PMC shall permit DAS and/or an
independent auditor selected by DAS to have access to such records from time to
time during ordinary business hours to verify compliance by PMC with such rules
and regulations.

                  6.3 PMC CERTIFICATE. PMC will provide DAS with the PMC
Certificate and any other documents required by a Regulatory Authority and that
PMC may reasonably provide relating to the PMC Product to enable DAS to conform
to regulatory requirements.

                                    ARTICLE 7

                             TITLE AND RISK OF LOSS

                  Title to the PMC Product shall at all times remain with DAS.
Risk of loss to each shipment of PMC Product shall pass to DAS upon its
transfer by PMC to the common carrier as specified in Article 6.1 hereabove.

                                    ARTICLE 8

                       WARRANTY, DISCLAIMER AND INSURANCE

                  8.1 WARRANTY. PMC warrants that all PMC Product delivered to
DAS:

-        will have been manufactured in compliance with Good Manufacturing
         Practices, in a GMP facility and in compliance any applicable
         regulations relating to the supply of the PMC Product as a raw material
         for producing DAS Product and in accordance with appropriate rules and
         regulations and regulatory guideline for each stage of production;

-        will have been manufactured, packaged, labeled and shipped in
         compliance with DAS specifications;

-        shall conform to the Protocol, DAS Specifications and PMC SOPs.

                  8.2 DISCLAIMER. PMC hereby disclaims any other warranties,
express or implied, including warranties as to its merchantability or fitness
for any particular purpose.

                                    ARTICLE 9

                                  COORDINATION

                  In order to coordinate the Services, the parties have decided
to create a Manufacturing Coordinating Committee as follows:

                  9.1 MEMBERS OF THE MANUFACTURING COORDINATING COMMITTEE

                  The parties have agreed to appoint 2 people of their
organization on the Manufacturing Coordinating Committee which are:

                  -        For PMC

-        A pharmaceutical Affairs representative

-        A qualified Industrial Operation Department Representative

                  -        FOR DAS

-        President of DAS SA or one of its designated persons

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       5

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-        CEO of DAS Inc or one of its designated persons

                  Internal or external expert may from time to time assist the
Manufacturing Coordinating Committee meetings according to the agenda of such
meeting at the request of one of the party which will inform the other party
within a reasonable delay before the date of the meeting in order to obtain its
approval.

                  9.2 OBJECTIVE OF THE MANUFACTURING COORDINATING COMMITTEE

                  The purpose of the Manufacturing Coordinating Committee shall
be to review the Manufacturing of PMC Product at a high quality and in a timely
manner, discuss annual forecasts for PMC Products and any possible adjustments
to the forecast that may be proposed by one of the parties from time to time,
and such other matters as the parties may mutually agree.

                  9.3 FUNCTIONING

                  The Manufacturing Coordinating Committee shall meet regularly
at least once each calendar quarter at Marcy-L'Etoile facilities or another
location mutually agreed upon by the Parties. The Manufacturing Coordinating
Committee may take action only by the unanimous written consent of the Parties
(all the members of the Manufacturing Coordinating Committee of one Party
representing one voting right). The minutes of the meetings shall be signed by
each party, each party keeping one copy.

                  If an issue remains unresolved after consideration by the
Manufacturing Coordinating Committee, the Manufacturing Coordinating Committee
may escalate it to the chief executive officers of the parties for resolution.

                                   ARTICLE 10

                                PRICE AND PAYMENT

                  10.1 PRICE.

                          The price of the PMC Product is set at the Effective
Date :

                  [***] per gram of PMC Product.

This Price [***].

                  10.2 PAYMENT. PMC shall invoice DAS for any batch of PMC
Product upon delivery of the same as specified hereunder. [***] after the date
of the corresponding invoice. No PMC Product shall be delivered prior to the
delivery date set forth on the applicable Manufacturing Order. Payments shall be
remitted by wire transfer in the invoice currency to a bank account to be
designated in writing from time to time by PMC.

                  [***] (and are not subject to a good faith dispute between the
parties) shall bear interest on the outstanding amount of [***].

                  10.3 ADDITIONAL EQUIPMENT COSTS. DAS shall pay PMC the
Equipment Costs as specified in Article 11 hereunder.

                                   ARTICLE 11

                       ACQUISITION OF ADDITIONAL EQUIPMENT

                  11.1 GENERAL. The Parties recognize that the acquisition of
Additional Equipment for manufacturing of PMC Product may be necessary to
supply DAS's future requirements of PMC Product that exceed [***] Batches of
PMC Product per year. The Parties contemplate that PMC's existing equipment
shall continue to be employed to supply PMC Product and that PMC may, upon
payment of the sums required by this Agreement and provided the relevant terms
and conditions of this Agreement are met, embark upon a program to acquire and
install Additional Equipment designed to meet any unexpected supply forecasts
of DAS in excess of [***] Batches of PMC Product at the PMC Facilities.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       6

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                  11.2 ADDITIONAL EQUIPMENT PROPOSAL PROCEDURE.

                           11.2.1   PROPOSAL

                  In the event the Parties determine in writing that Additional
Equipment is required to be purchased during the Term of this Agreement to
supply DAS's future requirements of PMC Product, PMC shall, within thirty (30)
days after each such determination, prepare and deliver to DAS a proposal for
the purchase and installation of such Additional Equipment (a "Proposal"). Each
Proposal shall include a detailed statement of all Additional Equipment Costs,
the schedule of required payments of such Additional Equipment Costs.

                           11.2.2   APPROVAL OF PROPOSAL

                  Upon DAS's receipt of each Proposal, DAS shall review the
Proposal and shall notify PMC promptly of any respects in which such Proposal is
not satisfactory. The Parties shall thereafter enter into discussions to resolve
any remaining differences and shall revise such Proposal accordingly. If and
when the Parties mutually agree in writing to proceed under such Proposal, such
Proposal shall be an Approved Proposal. for purposes of this Agreement. If the
Parties do not mutually agree to proceed under such Proposal, DAS shall accept
continued performance by PMC using PMC's existing capacity.

                  11.3 REIMBURSEMENT OF ADDITIONAL EQUIPMENT COSTS. Since PMC
would not, in the absence of this Agreement, undertake to acquire Additional
Equipment specified in an Approved Proposal, the Parties hereby acknowledge that
PMC requires certain undertakings from DAS concerning reimbursement of any
Additional Equipment Costs incurred by PMC. Accordingly, DAS agrees that all
Additional Equipment Costs incurred by PMC shall be reimbursed by DAS in
accordance with the mechanism established in Exhibit 8.

                  11.4 CANCELLATION BY DAS OF APPROVED PROPOSALS. PMC hereby
acknowledges that DAS shall have the right to cancel any Approved Proposal at
any time prior to the beginning of execution of the Approved Proposal by PMC.

                  11.5 LOSS OR DESTRUCTION OF EQUIPMENT OR PMC FACILITIES. In
the event that any of PMC's Facilities or Equipment used, or to be used, for the
production of the PMC Product is destroyed or incapacitated by fire or other
events beyond the control of PMC, PMC hereby agrees, at its expense, to use all
best efforts to provide alternative means of supplying in a timely fashion as
much of DAS requirements for PMC Product as soon as possible, and to use its
best efforts in order to commence rebuilding or restoring such facilities to
full capacity and/or replacing damaged Equipment. PMC also hereby agrees to
maintain at all times during the term of this Agreement, at its own expense,
applicable insurance against the losses described in this Article 11.5. Upon
written request, PMC shall furnish DAS with satisfactory evidence of such
insurance coverage.

                  11.6 OWNERSHIP OF ADDITIONAL EQUIPMENT. DAS hereby
acknowledges that all Additional Equipment once installed are and shall be the
property of DAS, and shall be held by PMC as DAS's bailee, and all rights of
title and ownership shall vest in DAS. Upon termination of this Agreement, PMC
shall arrange for the transfer of such equipment to DAS or its designee upon one
hundred and twenty (120) days prior written notice.

                  11.7 USE OF ADDITIONAL EQUIPMENT FOR OTHER PURPOSES. In the
event that PMC desires to use the Additional Equipment for any purpose other
than production of the PMC Product, PMC shall give DAS prompt written notice of
the same, and thereafter, the Parties shall negotiate in good faith (without
further obligation) the terms of appropriate compensation to be paid by PMC to
DAS for such use, based upon the percentage of the total capacity of the
Additional Equipment dedicated to such other use.

                                   ARTICLE 12

                           CHANGES OF THE PMC PRODUCT

                  12.1 REQUIRED BY DAS FOR REGULATORY PURPOSES. DAS will inform
PMC in writing of any modifications to the Protocol, DAS Specifications or PMC
Product required for regulatory purposes, including any changes to regulations
that could affect the PMC SOPs or the production of PMC Product. Such notice
shall be accompanied with a brief description of the corresponding regulation.
PMC shall exercise its best efforts, subject to the terms of this Section, to
timely and efficiently make such modifications as may be required by such
changes. PMC shall not make any change or modification described in the
applicable DAS Specifications, Protocol or the production of PMC Product unless
instructed in writing by DAS.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       7

<PAGE>

                  PMC will inform DAS of the amount of the additional costs
(including investment) PMC would incur due to the modification, if any, and if
DAS elects to adopt the modification DAS will reimburse PMC for required direct
capital expenditures in accordance with the mechanism set forth in Exhibit 8
hereto, and the relevant documents and related schedules will be revised
accordingly. PMC will provide DAS a written explanation of such investment and
additional costs.

                  If PMC is technically unable to comply with a proposed
modification or if DAS is unwilling to pay PMC's direct capital expenditures,
DAS shall have the option to withdraw the proposed modification (and hold PMC
harmless of any consequences due to such withdrawal) or to negotiate a payment
plan acceptable to PMC. DAS will notify PMC as soon as reasonably practical of
any changes to any DAS Specifications; procedures or other areas that are filed
with Regulatory Authorities and that could have an impact on PMC's performance
of this Agreement, and will advise PMC of the granting of approval and effective
date of such changes. Any such changes shall be deemed modifications under this
Section.

                  In the event that DAS decides not to adopt the modifications,
PMC shall continue to provide PMC Product in accordance with the DAS
Specification still in force and DAS shall hold PMC harmless of any consequences
resulting from the non-amendment of such DAS Specification.

                  12.2 MODIFICATION FOR NON-REGULATORY PURPOSES. Any
modification required to the production of PMC Product for non-regulatory
purposes shall be discussed between the parties. The parties shall negotiate in
good faith the changes to the PMC Product, the financial conditions and the time
schedule for the works to be performed.

                  In no event shall such a modification be implemented without
PMC's prior written approval, which shall not be unreasonably withheld and PMC
shall exercise its best efforts, subject to the terms of this Section, to timely
and efficiently make such modifications as may be required and agreed to
pursuant to this Section.

                  DAS shall hold PMC harmless of any consequences of such
changes.

                                   ARTICLE 13

                                QUALITY DISPUTES

                  13.1 PMC PRODUCT QUALITY DISPUTES. If DAS rejects any PMC
Product and if the parties have not agreed mutually on a remedy as per Article
6.2.3 of this Agreement, the parties, through the Manufacturing Coordinating
Committee shall timely consult with each other and attempt to resolve the
discrepancies. If the parties cannot resolve the discrepancies in a timely
manner after notification thereof to PMC, they shall promptly nominate a
Laboratory, which shall carry out analyses with respect to such Product as may
be jointly agreed upon by PMC and DAS and at the parties' joint expense.

                  The results obtained by the Laboratory shall be binding on the
parties for purposes of this Agreement.

                  If the results conclude that the PMC Product conformed to the
Protocol, DAS Specifications and PMC SOPs, DAS will reimburse PMC amounts paid
to the Laboratory. If the results conclude that the PMC Product does not conform
to the Protocol, DAS Specifications and PMC SOPs, PMC shall reimburse DAS
amounts paid to the Laboratory. In the event the Laboratory cannot conclude to
whether the PMC Product conform or not to the Protocol, DAS Specifications or
PMC SOPs, the parties shall equally share the Laboratory expenses.

                  Until such time as the Laboratory determines whether the PMC
Product conforms to PMC and DAS Specifications, DAS may withhold payment to PMC
of any amounts due in respect of the subject Manufacturing Order and deposit
such withheld payment in an interest-bearing bank account with a French bank,
and shall provide evidence of the same to PMC. In the event that the subject PMC
Product is determined to be conforming PMC shall receive all amounts in such
interest bearing bank account.

                  13.2 NON-PAYMENT FOR NON-CONFORMING PMC PRODUCT. If DAS
rejects any PMC Product and if it is determined by the Laboratory that such PMC
Product did not or would conform with the Protocol, DAS Specifications or PMC
SOPs, PMC shall at DAS's option use its best efforts to replace the non
conforming PMC Product as promptly as possible in accordance with the duration
of the production of PMC Product or issue a refund therefor, the costs of such
PMC Product shall not be paid to PMC, and PMC shall credit DAS with (i) DAS's
direct

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       8

<PAGE>

cost of the Immunogen used to produce the PMC Product that DAS demonstrates
cannot be shipped due to the defect; and (ii) the transportation charges paid
by DAS for such Immunogen.

                                   ARTICLE 14

                                QUALITY ASSURANCE

                  14.1 AUDIT OF PMC FACILITIES. Upon advance notice of [***] PMC
shall permit DAS representatives to enter PMC Facilities during regular business
hours for the purpose of making quality control inspections of the PMC
Facilities and limited to the part of the PMC Facilities in which PMC produces
the PMC Product.

                  In the event of an inspection by a Regulatory Authority, the
Regulatory Authority representative accompanied by DAS representatives shall be
permitted to enter PMC Facilities in the same conditions as described above.
However, the notice period in such case shall be [***] or such other time as may
be requested by Regulatory Authorities.

                  DAS shall cause its representatives and the Regulatory
Authority representatives to follow the security and facility access procedures
as are reasonably designated by PMC. PMC may require that at all times DAS
representative be accompanied by a PMC representative and that DAS
representative not enter some areas of the PMC facility to assure protection of
PMC or third party confidential information.

                  14.2 SAFETY PROCEDURES. PMC undertakes to adopt and enforce
safety procedures for the manufacturing of the PMC Product by PMC and handling
and disposal of waste relating to the PMC Product that comply with
environmental, safety and health requirements. Such responsibilities shall
include the proper disposal of waste in an appropriate manner consistent with
the nature of the waste and at a permitted waste disposal facility.

                                   ARTICLE 15

                                   DECLARATION

PMC shall use its best efforts to assist DAS, at DAS cost calculated according
to Exhibit 8, to address and resolve regulatory issues relating to the DAS
Product and more particularly, shall provide DAS, upon reasonable notice, and at
no cost, provide all necessary and available data relating to the PMC Product in
order to obtain regulatory approvals to develop and commercialize the DAS
Product. Without limiting the foregoing, DAS shall diligently process its own
ELA or the appropriate supplement of the existing ELA in accordance with a
timetable sufficient to permit DAS to meet its own timetable with regard to its
filing of a IND, 8LA and PLA's for DAS Products. PMC acknowledges and agrees
that (a) it shall be required to pass a preapproval inspection by the FDA and
other Regulatory Authorities prior to DAS obtaining regulatory approval by such
authority, (b) it has reviewed, understands and shall comply with all applicable
laws, regulations and other requirements of the FDA and other Regulatory
Authorities in manufacturing, processing and packaging as active ingredient bulk
of the PMC Products, and (c) it shall provide DAS with copies of all notices it
or its contractors receive from Regulatory Authorities that could affect the PMC
Product, DAS Product or the ability to manufacture the PMC Product in the PMC
Facilities. PMC shall provide any manufacturing, quality control or quality
assurance data and other information relating to obtaining all approvals from
all Regulatory Authorities to commercially market and sell DAS Product
(including without limitation, any other information as may be useful or
required (in DAS'S reasonable opinion or upon request of a Regulatory Authority)
for FDA and other Regulatory Authorities approval of DAS Products) to the
public.

                                   ARTICLE 16

                                   SUPERIORITY

                  No provision on DAS's purchase order form or on PMC's general
conditions of sale or invoice which may purport to impose different conditions
upon DAS or PMC shall modify or otherwise alter the terms of this Agreement.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       9

<PAGE>

                                   ARTICLE 17

                                 CONFIDENTIALITY

(a)  -   GENERAL

         Except as expressly set forth in this Article 17, each party shall
         cause its respective Affiliates, officers, directors, employees, agents
         and subcontractors (collectively, "Representatives") to keep
         confidential any and all technical, commercial, scientific and other
         data, processes, documents or other information (whether in oral form
         and identified as confidential within 30 days after the date of
         disclosure, or if written form, if marked as "Confidential" at the time
         of disclosure) or physical object (including, without limitation,
         intellectual property, marketing data, agreements between any party and
         a third-party, license applications, and business plans and projections
         of any party) that have been marked as "confidential" at the time of
         disclosure) acquired from the other party (the "Other Party"), its
         Affiliates or its Representatives after the Effective Date
         ("Confidential Information"), and each party shall not disclose
         directly or indirectly, and shall cause its Representatives not to
         disclose directly or indirectly, any Confidential Information to anyone
         outside such Person and each of their Affiliates and their respective
         Representatives, except that the foregoing restriction shall not apply
         to any information disclosed hereunder to any party, if such Person
         (the Receiving Person") can demonstrate that such Confidential
         Information:

         (i)      is or hereafter becomes generally available other than by
                  reason of any breach or default by the Receiving Person, any
                  of its Affiliates or any Representative of the foregoing with
                  respect to a confidentiality obligation under this Agreement;

         (ii)     was already known to the Receiving Person or such affiliate or
                  Representative;

         (iii)    is disclosed to the Receiving Person or such affiliate or
                  Representative by a third party who has the right to disclose
                  such information;

         (iv)     is independently developed by the Receiving Person;

         (v)      based on such Person's good faith judgement with the advice of
                  counsel, is otherwise required to be disclosed in compliance
                  with applicable legal requirements to a public authority.

         Whenever the Receiving Person becomes aware of any state of facts which
         would or might result in disclosure of Confidential Information
         pursuant to subparagraph (v) above, it shall, if possible, promptly
         notify the Person making disclosure "Disclosing Person") prior to any
         such disclosure so that the Disclosing Person may seek a protective
         order or other appropriate remedy and/or waive compliance with the
         provisions of this Agreement.

         In any event, if the Receiving Person is unable to promptly notify the
         Disclosing Person or if such protective order or other remedy is not
         obtained, or if the Disclosing Person waives compliance with the
         provisions of this Agreement, the Receiving Person will furnish only
         that portion of the information which it is advised by counsel is
         legally required and will exercise reasonable efforts to obtain
         assurance that confidential treatment will be accorded the Confidential
         Information.

         Each party shall be entitled, in addition to any other right or remedy
         it may have, at law or in equity, to an injunction, without the posting
         of any bond or other security except as required by the relevant laws,
         enjoining or restraining any other party from any violation or
         threatened violation of this Section 8.1.

(b)  -   USE OF CONFIDENTIAL INFORMATION

         Each party agrees that no Confidential Information shall:

         (i)      be used in its own business except as necessary to exercise
                  the rights and obligations of such Party under this Agreement;

         (ii)     be assigned, licensed, sublicensed, marketed, transferred or
                  loaned, directly or indirectly to any third party other than a
                  Representative or an Affiliate Representative of such party,
                  except as

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       10

<PAGE>

                  necessary or contemplated for the exercise of the rights
                  and obligations of the Parties under this Agreement;

         The obligations set forth in this Article 17 shall extend to copies, if
         any, of Confidential Information made by any Representatives referred
         to in paragraph (a) and to documents prepared by such Persons which
         embody or contain Confidential Information.

(c)  -   PROTECTION OF CONFIDENTIAL INFORMATION

         Each party shall deal with Confidential Information so as to protect it
         from disclosure with a degree of care not less than that used by it in
         dealing with its own information intended to remain exclusively within
         its knowledge and shall take reasonable steps to minimise the risk of
         disclosure of Confidential Information which shall include, without
         limitation, ensuring that only those Persons who have a bona fide need
         to know such Confidential Information for purposes permitted or
         contemplated by this Agreement shall have access thereto. Each party,
         shall notify all of its Representatives who have access to Confidential
         Information of its confidentiality and the care therefor required, and
         shall obtain from any Affiliate or any agent or subcontractor who is a
         Representative that is permitted access to such Confidential
         Information in accordance with this Article 17, an agreement of
         confidentiality incorporating the restrictions set forth herein.

(d)  -   SURVIVAL OF OBLIGATIONS

         The obligations set forth in this Article 17 shall survive the
         termination of this Agreement for a period of five (5) years.

(e)  -   RETURN OF CONFIDENTIAL INFORMATION

         Within thirty (30) days after the termination of this Agreement, the
         Receiving Person shall (and shall cause its Affiliates' Representatives
         and its Affiliates to) return to the Disclosing Person or destroy all
         related documents and tangible items then in its possession which it
         has received from the Disclosing Person or any affiliate or
         Representative thereof pertaining, referring or relating to the
         Disposing Person's Confidential Information, as well as all copies,
         summaries, records, descriptions, modifications, and duplications that
         it, or any of its Affiliates or Representatives, has made from the
         documents or tangible items received from the Disclosing Person or any
         affiliate or Representative thereof; provided, however, that the
         Receiving Person may retain one copy of each document in its legal fees
         solely to permit the Receiving Person to continue to comply with its
         obligations hereunder and, in addition, may upon notice to the
         Disclosing Person, retain in its legal files or in the office of
         outside legal counsel one copy of any document solely for use in any
         pending legal proceeding to which such document relates.

                                   ARTICLE 18

                                    INDEMNITY

                                    (a) Subject to PMC's indemnity obligations
for violations of Article 8 above (which obligations shall take precedence) DAS
shall indemnify, hold harmless and defend PMC, its directors, officers, and
employees from and against any and all claims, costs, demands, liabilities,
losses, damages and expenses of whatever nature, including costs of recall made
against or sustained by them, arising out of the use or sale of the PMC Product
or the DAS Product by DAS or its customers.

                                    (b) PMC shall indemnify and hold DAS, its
affiliate's, directors, officers, agents and employees from and against any and
all claims, costs, demands, liabilities, losses, damages and expenses of
whatever nature, including costs of recall made against or sustained by them,
arising out of or in connection with this Agreement caused by the negligence or
willful misconduct of PMC or any breach of PMC's warranties set forth under
provision 8.1 hereabove.

                                    (c) In the event of any claim being made
against a party ("the Indemnified Party") for which the other party ("the
Indemnifying Party") has agreed to indemnify the Indemnified Party under this
Agreement, the Indemnifying Party shall be promptly notified thereof and may at
its own expense conduct all negotiations for the settlement of the same and any
litigation that may arise therefrom. The Indemnified Party shall use its
commercially reasonable efforts to not at any time make any admission or take
any steps which might be prejudicial to the settlement or successful defense by
the Indemnifying Party of any claim or demand until the

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       11

<PAGE>

Indemnifying Party has been notified of the claim and has stated its
intention not to negotiate or defend the claim provided that the indemnifying
Party shall act promptly throughout.

                                   ARTICLE 19

                              TERM AND TERMINATION

                  19.1 TERM RENEWAL. This Agreement shall take effect as of
the Effective Date and shall, unless terminated earlier according to this
Article 19, continue in effect for a period of ten (10) years after First
Commercial Sale. After such 10 year period, PMC shall exercise commercially
reasonable efforts to ensure continuous supply of PMC Product on financial
terms reasonably acceptable to both parties, provided that (i) annual
forecasts of PMC Product are at least [***] of PMC Product per year (ii) the
parties shall negotiate in good faith such annual renewals, and (iii) all
other terms of the Agreement shall apply to such renewals or extensions, and
(iv) in no event shall this [********] However, in the event of a renewal of
the Agreement for the second two-year period, the parties shall renegotiate
in good faith the financial conditions of the Agreement.

                  19.2 TERMINATION WITHOUT CAUSE.

                           19.2.1   AUTOMATIC TERMINATION.

                                    This Agreement shall automatically terminate
upon written notice of one of the parties in the event of termination for
whatever reason of that certain Patent and Know-How License Agreement signed on
this same date between the parties.

                           19.2.2   FAILURE TO OBTAIN FDA APPROVAL.

                                    (a) DAS may terminate this Agreement without
cause upon [***] to PMC if (I) it determines that the BLA or other relevant
product license to market the DAS Product will not be approved by the FDA or the
Agence Europeenne du Medicament within a reasonable time at a reasonable cost,
or (II) PMC fails to obtain an ELA supplemental approval (and the equivalent
approvals from the Regulatory Authorities for France and the European Union),
with respect to the PMC Product and the DAS Product [***].

                                    (b) PMC may terminate this Agreement without
cause upon [***] to DAS if a BLA or other relevant product license has not been
approved within [***] of the Effective Date and DAS cannot demonstrate to PMC's
reasonable satisfaction within [***] period that, such approval is forthcoming.

                           19.2.2 EXCESSIVE COST. If at any time DAS determines
that, due to competitive conditions, currency fluctuations or otherwise, the
price of PMC Product and Additional Equipment Costs will be so high that DAS
will be unable to sell DAS Product at a price that will result in a reasonable
profit to DAS, DAS may, [***], terminate this Agreement without cause.

                  19.3 TERMINATION FOR CAUSE. This Agreement may be terminated
by PMC upon [***], but only if DAS fails to pay an amount when due that is not
subject to a good faith dispute between the parties, and DAS has not cured such
breach within [***]. This Agreement may be terminated by DAS in the event that
PMC fails to perform or otherwise breaches any of its material obligations under
this Agreement, by giving notice to PMC of its intent to terminate and stating
the grounds therefor. PMC shall have sixty (60) days from the date of receipt
thereof cure the failure or breach. In the event the breach is not cured within
the time period set forth herein, then this Agreement shall, at the option of
DAS, terminate at the end of [***]. Except as otherwise expressly set forth in
this Agreement, neither party shall have the right to terminate this Agreement,
and any disputes between the parties shall be resolved pursuant to Section 20.9.

                  19.4 EFFECT OF TERMINATION OR EXPIRATION

                           19.4.1   GENERAL

                  Upon the expiration or termination of this Agreement, PMC
shall notify DAS of the amount of PMC Product it has on hand, and DAS shall
purchase such PMC Product at its applicable transfer price determined pursuant
to Article 10.1 above except that DAS shall not be obligated to purchase more
than the quantity of PMC Product specified in the most recent Manufacturing
Order and DAS shall have no obligation to purchase any such

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       12

<PAGE>

PMC Product if a basis for the termination is a failure of the PMC Product to
meet the PMC SOPs or DAS Specifications, Protocol or otherwise be warranted
product. Termination shall not affect any available remedies.

                           19.4.2   FURTHER EFFECTS OF TERMINATION

                  In the event of any termination of this Agreement, or in the
event that DAS elects to establish an equivalent capability at its own or a
different facility, PMC shall at DAS's request and at DAS's cost, assist DAS in
all ways reasonably requested by DAS to transfer the production of PMC Product
to DAS or its designated agents including, but not limited to, transfer of any
part of the PMC SOPs reasonably necessary for DAS to perform or have performed
the equivalent production capability. PMC shall designate for a reasonable
period to be agreed upon by the parties, a senior-level manager as liaison who
shall be responsible for facilitating and coordinating PMC's efforts to effect
such transfer. PMC and DAS shall negotiate in good faith the reasonable cost and
the reasonable period of time for which PMC shall provide the technical
assistance. PMC shall only be obligated to provide technical assistance one
time. PMC shall not liable for the inability of DAS to successfully complete a
transfer.

                  19.5 SURVIVAL. In addition, anything herein to the contrary
notwithstanding, the following provisions of this Agreement shall survive
termination of this Agreement: Articles 7, 8, 13, 16, 17, 20, 18, 19, 21, 11.3,
11.5 and 11.6 and Section 10.2 and right to payments that have accrued prior to
the date of termination, shall survive termination.

                                   ARTICLE 20

                                  FORCE MAJEURE

                  No Party hereto shall be responsible or liable to the other
Party hereto for any failure to perform any of its agreements, covenants or
obligations under this Agreement if such failure results from events or
circumstances reasonably beyond the control of such Party including, without
limitation, war or other national emergency; riot; fire, explosion, good or
other Act of God; general and long lasting strike affecting the entire activity
of either party, any injunction, decree, order, law or regulation of any public
authority; or any inability to obtain electricity, fuel or raw material
(collectively, "Events of Force Majeure").

                  The affected party shall (i) forthwith inform the other party
in writing of the occurrence of the Event of Force Majeure and (ii) exert all
best efforts to eliminate, cure or overcome any such Event of Force Majeure and
to resume performance hereunder with all possible speed; provided, however, that
nothing herein shall require the party to settle on terms unsatisfactory to such
party any strike. To the extent that an Event of Force Majeure continues for a
period in [***], the parties agree to negotiate in good faith either (i) to
resolve the Event of Force Majeure, if possible, (ii) to extend the time period
to resolve, eliminate or overcome such Event or (iii) to terminate this
Agreement.

                                   ARTICLE 21

                            MISCELLANEOUS PROVISIONS

                  21.1 INDEPENDENT CONTRACTOR. PMC shall supply PMC Product as
an independent contractor and nothing contained herein shall be construed to be
inconsistent with that relationship or status. PMC and its employees shall not
be considered employees or agents of DAS. This agreement shall not constitute,
create or in any way be interpreted as a joint venture, partnership or business
organization of any kind.

                  21.2 NO ASSIGNMENT. Neither party shall transfer or assign
this Agreement, in whole or in part without the other party's prior written
consent, except that either party may transfer, assign and delegate this
Agreement to an Affiliate or in connection with a merger, reorganization or sale
of substantially all of its assets, without the other party's consent.

                  21.3 NOTICES. Notices and other communications required or
called for under this Agreement shall be in writing, shall be transmitted by
certified mail postage prepaid, and shall be deemed delivered upon receipt by
the party to whom it is addressed.

                  In the case of DAS such communications shall be addressed to.

                  DAS, 2 rue de Cnucy, 44000 Nantes, France.  Attention:
                  President
                  DAS Inc. 1430 O'Brien Drive, Suite E, Menlo Park CA 94025 USA
                  Attention: CEO

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       13

<PAGE>

                  In the case of PMC, such communications shall be addressed to:

                  PASTEUR MERIEUX Serums & Vaccins
                  58, avenue Leclerc
                  69007 Lyon
                  FRANCE
                  Attention: General Counsel

or to the attention of such other individual or to such other address as either
party may give to other in writing.

                  21.4 NO WAIVER. The failure of either party to enforce at any
time for any period the provisions hereof shall not be construed to be a waiver
of such provisions or of the right of such party thereafter to enforce each such
provision.

                  21.5 SEVERANCE. If any provision of this Agreement should be
or become fully or partly invalid or unenforceable for any reason whatsoever or
violate any applicable law, this Agreement is to be considered divisible as to
such provision and such provision is to be deleted from this Agreement, and the
remainder of this Agreement shall be deemed valid and binding as if such
provision were not included. A suitable provision which, as far as legally
possible, comes nearest to what the parties desired according to the sense and
purpose of this Agreement had this point been considered when concluding this
Agreement shall be substituted for any such provision deemed to be deleted.

                  21.6 LIST OF EXHIBITS. The Exhibits listed in this provision
and attached herewith are fully part of this Agreement and cannot be modified
unless mutually agreed between the parties:

                  Exhibit 1         PMC Facilities
                  Exhibit 2         Protocol
                  Exhibit 3         PMC SOPs and DAS Specifications
                  Exhibit 4         DAS Certificate
                  Exhibit 5         PMC Certificate
                  Exhibit 6         Manufacturing Order
                  Exhibit 7         Laboratory
                  Exhibit 8         Forecasts during Development Period
                  Exhibit 9         Non binding Guidelines
                  Exhibit 10        Direct Costs

                  21.7 GOVERNING LAW. This Agreement shall be governed by
Californian Laws.

                  21.8 DISPUTE RESOLUTION.

Any and all disputes arising in connection with this Agreement which will not
be solved on an amicable basis between the parties shall be finally settled
by arbitration under the Rules of Conciliation and Arbitration of the
International Chamber of Commerce, rules that the Parties recognizes that
they know. The arbitration shall be conducted in Paris, France, in English by
one arbitrator if the dispute involves a claim of damage [***] in accordance
with the said rules. The arbitrator(s) shall apply French law to the merits
of the case. The arbitration shall be final and binding upon the parties.

                  21.9 HEADINGS.

The Articles and article headings included in this Agreement are for reference
purpose only and shall not affect the meaning or interpretation of this
Agreement.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       14

<PAGE>

                  IN WITNESS WHEREOF, the parties hereto have caused these
presents to be signed by their respective corporate officers, authorized as of
the day and year first above written.

DAS SA                                         PASTEUR MERIEUX SERUMS ET VACCINS


By:     /s/ Maryvonne Hiance                   By:  /s/ Michel Greco
    --------------------------------               -----------------------------
Name:   Maryvonne HIANCE                       Name:  Michel GRECO
Title:  President                              Title:  DIRECTEUR GENERAL


DAS INC


By:     /s/ Stanley Kaplan
    --------------------------------
Name:   Stanley KAPLAN
Title:  Chief Executive Officer & President

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                       15

<PAGE>

                                    EXHIBIT 1

                                 PMC FACILITIES

[********]






[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.



                                       16
<PAGE>

                                    EXHIBIT 2

                                 COC AB PROTOCOL




[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.


                                        17
<PAGE>

                                    EXHIBIT 3

                                    PMC SOPS

THE FOLLOWING PMC SOP'S MAY BE MODIFIED BY APPLYING THE PROVISIONS OF THIS
AGREEMENT

Procedure technique PMC T [********]        [***]

Procedure technique PMCT[********]          [***]

Procedure technique PMC T [********]        [***]

Procedure technique PMC T [********]        [***]

Procedure technique PMC T [********]        [***]

Les autres specifications techniques de PMC pourront etre modifiees par PMC a
tout moment mais auditable par IMTIX-SangStat

Procedure technique PMC T [********]        [***]
Procedure technique PMC T [********]        [***]
rongeurs
Procedure technique PMC T [********]        [***]
Procedure technique PMC T [********]        [***]

This exhibit shall be completed with PMC SOP's redrafted upon existing SOP's
relating to other products manufactured by PMC.

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                         18
<PAGE>

                               EXHIBIT 4

                           DAS CERTIFICATE

===============================================================================
                           DAS CERTIFICATE

COC AB ANTIGENE
-------------------------------------------------------------------------------
         Batch N(DEG.)                              Tests results

         ----                                         Anormal Toxicity

                                                      Sterility

-------------------------------------------------------------------------------
We certify that all the COC ab Antigene mentioned in this certificate have been
released for horse imminuzation to produce Anticocaine plasma

                                                         Name:  _____________
                                                        Title:  _____________
                                                         Date:  _____________
===============================================================================

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                    19

<PAGE>

                                    EXHIBIT 5

                                 PMC CERTIFICATE

===============================================================================
                        PASTEUR MERIEUX SERUMS & VACCINS

Nous, soussignes, certifions que la solution Fab'2 vrac anti cocaine COC ab du
lot:

         n(DEG.) _______________

a ete produit conformement aux specifications de DAS mentionne au contrat en
date du Juin 1999 aux procedures techniques de PMC applicables et aux Bonnes
Pratiques de Fabrication.

Certificat de controles:  ci-joint

                                  Fait a Marcy l'Etoile, le  ________________
                                                       Nom:  ________________
                                                  Fonction:  ________________

                                                 Signature:  ________________

===============================================================================


[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                     20

<PAGE>


Pasteur Merieux Serums & Vaccins
         Direction des controles

                              CERTIFICAT D'ANALYSE

                          SOLUTION DE COC AB FAB'2 10%

                        LOT N(DEG.): __________________

ASPECT                                                        :      Conforme

DOSAGE DES PROTEINES TOTALES                                  :      g/100ml

RECHERCHE DES PROTEINES ETRANGERES                            :      Conforme

TEST DE DIGESTION                                             :      Conforme

ESSAI DE STERILITE BACTERIENNE ET FONGIQUE                    :      Conforme

ESSAI DES PYROGENES                                           :      Conforme

HPLC GEL FILTRATION
         [********]                                           :      %
         [********]                                           :      %
         [********]                                           :      %

CONCLUSION:

Date:                                      le directeur de Services de Controle

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                        21

<PAGE>

                                    EXHIBIT 6

                               MANUFACTURING ORDER

===============================================================================
                                       DAS

BON DE COMMANDE N(DEG.) ___________;

            SOLUTION DE PRINCIPE ACTIF FAB'2 VRAC ANTI COCAINE COC AB

Volume total ___________________ litres, soit _______________ grammes

Nombre de lots estimes:  ________________

Periode de livraison:      du _______/___/           au ________/____/____

DAS s'engage a livrer a temps les quantites d'antigenes necessaires a
l'immunisation du nombre de chevaux correspondant a la quantite de plasma
necessaire a l'obtention du produit.

Estimatif du montant de la commande ___________________: _____________ FRF HT

                                        (Nb grammes x Prix/g)

Fait a
Le

-----------------
Responsible Achat

DAS

===============================================================================

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                    22
<PAGE>

                                    EXHIBIT 7

                                   LABORATORY


Ecole Nationale Veterinaire
7 avenue du General Leclerc
94704 MAISONS ALFORT Cedex
Tel: 01.42.96.71.00

[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                      23

<PAGE>

                                    EXHIBIT 8

                       FORECAST DURING DEVELOPMENT PERIOD



[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                        24

<PAGE>

                                    EXHIBIT 9

                      NON BINDING GUIDE LINES ON THE TIMING


TIME LINES FOR FIRST BATCH DURING MANUFACTURING PERIOD

Manufacturing order for 1st batch [***]                           [***]

Reception of horses [***]                                         [***]

Quarantine                                                        [***]

Immunization                                                      [***]

Processing and controls                                           [***]


Next batches:  [***]


[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                        25

<PAGE>

                                   EXHIBIT 10

                            PMC PRODUCT DIRECT COSTS

"Direct Cost" shall mean the direct cost attributable or allocable to the
specific activity for which they are to be charged. The components of direct
costs are limited to the following: personnel salaries, cost of supplies, cost
of materials, contracted and outside services and support costs. Specifically
(depending on the activity), Direct Costs may include one of more of components
set forth below:

                          BREAKDOWN OF THE DIRECT COST

The direct cost is composed of 4 main categories of costs.

<TABLE>
<CAPTION>

------------------------ ----------------------------------------- ---------------------------------------------------
Category                 Including                                 Comments
------------------------ ----------------------------------------- ---------------------------------------------------
<S>                   <C>                                        <C>
Raw materials            Bill of material
------------------------ ----------------------------------------- ---------------------------------------------------
Direct Labor             Payroll                                   Gross salary, excluding interessement et
                         Overtime                                  participation

                         Medical benefits                          Payroll taxes
------------------------ ----------------------------------------- ---------------------------------------------------
Overhead                 Product manager                           Salary, payroll taxes,...
                         Utilities

                                                                   QC environmental tests, technical assistance,
                                                                   process optimization

                         Equipment items
                         Small equipment items

                         Services rendered
------------------------ ----------------------------------------- ---------------------------------------------------

</TABLE>


All other costs considered indirect are not allocated or attributable, and are
mainly:

         -        Administrative cost (including phone expenses which are not
                  allocated to cost centers)
         -        Executives and site production administrative people
         -        Purchasing and warehousing
         -        Quality assurance/metrology - Depreciation
         -        Taxes (including `taxe professionnelle')
         -        Pharmaceutical responsibility
         -        Product liability insurance
         -        Bonus (interessement et participation)
         -        Distribution costs
         -        Site expenses (including site security, guarding)


[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT
TO THE OMITTED PORTIONS.

                                 26