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                                                                Exhibit 10.39


Confidential treatment has been requested for portions of this document. 
Brackets indicate portions of text that have been omitted. A separate filing 
of such omitted text has been made with the Commission as part of the 
Company's application for confidential treatment.


                 RESEARCH COLLABORATION AND LICENSE AGREEMENT (U.S.)


    This Agreement is made and entered into this 7th day of March, 1997 by and
between BIOGEN, INC. (hereinafter referred to as "BIOGEN"), a Massachusetts
corporation located at 14 Cambridge Center, Cambridge, MA 02142, and CV
THERAPEUTICS, INC., a Delaware corporation, located at 3172 Porter Drive, Palo
Alto, CA 94304 (hereinafter referred to as "CVT").

    WHEREAS, BIOGEN is a biopharmaceutical company which develops,
manufactures, markets and sells pharmaceutical products for human healthcare;
and

    WHEREAS, CVT is the owner and/or exclusive licensee of certain technology,
patent rights and other proprietary know-how related to PRODUCTS as hereinafter
defined; and

    WHEREAS, BIOGEN desires to obtain an exclusive right and license in and to
such technology, patent rights and proprietary know-how in the TERRITORY as
hereinafter defined; and

    WHEREAS, BIOGEN desires to support additional research related to PRODUCTS;
and

    WHEREAS, CVT is willing to grant the exclusive right and license desired by
BIOGEN and to participate in the conduct of research supported by BIOGEN; and

    WHEREAS, CVT is granting an exclusive right and license in and to such
technology, patent rights and proprietary know-how outside the TERRITORY to
Biotech Manufacturing Limited ("BML") pursuant to a Research Collaboration and
License Agreement (Europe) of even date herewith (the  "BML AGREEMENT") .

    NOW, THEREFORE, in consideration of the mutual promises and other good and
valuable consideration, the parties agree as follows:

SECTION 1.    DEFINITIONS.

    The terms used in this Agreement have the following meaning:

    1.1  The term "Adenosine A(1) Antagonist" shall mean a molecule that 
[  *  ] compound being referred to herein as  a "Test Compound"), the 
[  *  ], and such Test Compound meets the following specifications measured 
concurrently in a validated in vitro assay:

         (I)  [  *  ]

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         (II) [  *  ]

    Notwithstanding the foregoing, if CVT is able to establish in a model 
reasonably acceptable to BIOGEN that the principal activity of a Test 
Compound IN VIVO is as [  *  ] such Test Compound shall be excluded from the 
definition of Adenosine A(1) Antagonists.

    1.2  The term "AFFILIATE" as applied to either party shall mean any 
company or other legal entity other than the party in question, in whatever 
country organized, controlling, controlled by or under common control with 
that party. The term "control" means ownership or control, directly or 
indirectly, of at least fifty percent (50%) of the outstanding stock or 
voting rights or the right to elect or appoint a majority of the directors.

    1.3  The term "first AGREEMENT YEAR" shall mean the twelve month period 
commencing on the EFFECTIVE DATE.  With respect to any year after the first 
AGREEMENT YEAR, the term "AGREEMENT YEAR" shall mean the twelve month period 
commencing upon an anniversary of the Effective Date.

    1.4  The term "BIOGEN CVT-124 TECHNOLOGY" shall mean any information, 
data (including all chemical, pharmacological, toxicological, clinical, 
assay, manufacturing and control information, data and test results, 
including negative results), ideas, concepts, formulas, trade secrets, 
methods, procedures, designs, materials, compositions, plans, diagrams, 
applications, specifications, techniques, records, practices, processes, 
research, know-how, inventions, discoveries and the like first conceived and 
first reduced to practice by BIOGEN or its AFFILIATES in the performance of 
any of its work under or pursuant to this Agreement which are necessary or 
useful for the manufacture or use of CVT-124 or other PRODUCTS.  

    1.5  The term "BIOGEN CVT-124 PATENTS" shall mean all patents and pending 
patent applications (which for purposes of this Agreement shall be deemed to 
include certificates of invention and applications for certificates of 
invention and priority rights, provisional patent applications, statutory 
invention registrations, applications for statutory invention registrations, 
and any foreign equivalents thereof) owned by BIOGEN or its AFFILIATES 
throughout the TERRITORY which claim the BIOGEN CVT-124 TECHNOLOGY or any 
part thereof, including any provisional applications, substitutions, 
extensions, reissues, reexaminations, renewals, continuations, 
continuations-in-part, divisionals and supplemental protection certificates. 


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    1.6  The term "CALENDAR QUARTER" shall mean the period of three (3) 
consecutive calendar months ending on March 31, June 30, September 30 or 
December 31, as the case may be.

    1.7  The term "CVT-124" shall mean the [  *  ] of epoxy norbornyl 
xanthine as defined as CVT-124 in the IND filed on September 20, 1995 and as 
further described in U.S. Patent Application Serial No. [  *  ].

    1.8  The term "CVT PATENT RIGHT(S)" shall mean all patents and pending 
patent applications (which for purposes of this Agreement shall be deemed to 
include certificates of invention and applications for certificates of 
invention and priority rights, provisional patent applications, statutory 
invention registrations, applications for statutory invention registrations, 
and any foreign equivalents thereof) throughout the TERRITORY that claim CVT 
TECHNOLOGY or any part thereof, including any provisional applications, 
substitutions, extensions, reissues, reexaminations, renewals, continuations, 
continuations-in-part, divisionals and supplemental protection certificates, 
which CVT owns (in whole or in part) or to which CVT otherwise has a 
transferable right as of the EFFECTIVE DATE or at any time during the term of 
this Agreement, including but not limited to CVT's rights in any RESEARCH 
PATENT RIGHTS and CVT's rights obtained under the UFRFI LICENSE.   CVT PATENT 
RIGHTS as of the EFFECTIVE DATE are set forth in APPENDIX A hereto.

    1.9  "CVT TECHNOLOGY" shall mean any information, data (including all 
chemical, pharmacological, toxicological, clinical, assay, manufacturing and 
control information, data and test results, including negative results), 
ideas, concepts, formulas, trade secrets, methods, procedures, designs, 
materials, compositions, plans, diagrams, applications, specifications, 
techniques, records, practices, processes, research, know-how, inventions, 
discoveries and the like which CVT owns (in whole or in part) or to which CVT 
otherwise has a transferable right as of the EFFECTIVE DATE or at any time 
during the term of this Agreement, which relate to CVT-124 or any other 
Adenosine A(1) Antagonist, including but not limited to CVT's rights in the 
RESEARCH INFORMATION, the RESEARCH MATERIALS and the RESEARCH INVENTIONS, and 
CVT's rights under the UFRFI LICENSE.

    1.10 The term "EFFECTIVE DATE" shall mean March 10, 1997.

    1.11 The term "FTE" shall mean the equivalent of a full year of effort on 
a full time basis of a scientist or other professional possessing skills and 
experience necessary to carry out applicable tasks under the RESEARCH PROGRAM.

    1.12 The term "FIRST COMMERCIAL SALE" shall mean the initial transfer by 
BIOGEN or any of its AFFILIATES or SUBLICENSEES of a PRODUCT to a 


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THIRD PARTY in exchange for consideration, following marketing approval by 
the appropriate governmental agency for the country in which the transfer is 
made.

    1.13 The term "MAA" shall mean an application for regulatory approval to 
sell  PRODUCT in the European Union and similar in purpose to an NDA in the 
United States.

    1.14 The term "MAJOR MARKET" shall mean the United States.

    1.15 The term "NDA" shall mean a New Drug Application or Product License 
Application or equivalent filing filed for PRODUCT with the U.S. Food and 
Drug Administration ("FDA").

    1.16 The term "NDR" shall mean an application for regulatory approval to 
sell PRODUCT in Japan and similar in purpose to an NDA in the United States.

    1.17 The term "NET SALES" shall mean the [  *  ] of BIOGEN and its 
AFFILIATES with respect to the sale of PRODUCT, less: 

         (i)  trade, quantity, cash or other discounts [  *  ] allowed not 
exceeding amounts customary in the trade, including, without limitation, 
governmental program discounts and rebates (e.g., Medicaid, Medicare, VA, 
etc.)

         (ii)  sales taxes, tariff duties and/or use taxes directly imposed 
on and with reference to particular sales;

         (iii)  packing, transportation and insurance prepaid or allowed; and

         (iv)  amounts allowed or credited on rejects, returns or retroactive 
price reductions.

A sale or transfer of PRODUCT by BIOGEN to an AFFILIATE for re-sale of 
PRODUCT by such AFFILIATE shall not be considered a sale for the purpose of 
this provision but the resale of PRODUCT by such AFFILIATE to a THIRD PARTY 
shall be a sale for such purposes.  A "sale" shall mean a transfer or other 
disposition for consideration, but shall not include transfers or 
dispositions at no cost for pre-clinical, clinical, regulatory or 
governmental purposes or disposition of PRODUCT at no cost for promotional 
purposes.  

    In the event that PRODUCT is sold in the form of  a combination product
containing one or more active ingredients or components in addition to CVT-124
or, if applicable, another Adenosine A(1) Antagonist, NET SALES shall be
determined by multiplying NET SALES of the combination product (as defined by
reference to the 

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                                       4.

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standard NET SALES definition) during the applicable payment period by the 
fraction A/A+B where A is the average sale price of PRODUCT when sold 
separately in finished form and B is the average sale price of the other 
active ingredients or components when sold separately in finished form in 
each case during the applicable payment period in the country in which the 
sale of the combination product was made, or if sales of both the PRODUCT and 
the other active ingredients or components did not occur in such period, then 
in the most recent payment period in which sales of both occurred.  In the 
event that such average sale price cannot be determined for both PRODUCT and 
all other active ingredients or components included in the combination 
product, NET SALES for purposes of determining payments under this Agreement 
shall be calculated by multiplying the NET SALES of the combination product 
by the fraction C/C+D where C is the fair market value of the CVT-124 (or 
other Adenosine A(1) Antagonist) contribution to the combination and D is the 
sum of the fair market values of all other active components or ingredients 
included in the combination product, in each case, as determined by BIOGEN in 
good faith. 

    1.18 The term "OPERATING COMMITTEE" shall have the meaning set forth in 
Section 7.1 of this Agreement.

    1.19 The term "PHASE II PERFORMANCE ASSESSMENT STUDY" shall mean a Phase 
II study of intravenous CVT-124 in patients with [  *  ] congestive heart 
failure (CHF). The study will be designed to demonstrate as a primary 
endpoint, [  *  ] The study design may be optimized by BIOGEN as additional 
data is gathered from other trials.

    1.20 The term "PHASE III TRIAL" shall mean a randomized clinical trial 
designed to show efficacy and safety of a PRODUCT and intended to be 
submitted as part of the application for marketing approval of such PRODUCT.

    1.21 The term "PRODUCT" shall mean any article, composition or material 
that comprises, contains or is CVT-124 or another Adenosine A(1) Antagonist, 
the manufacture, import, use or sale of which is covered by a VALID CLAIM of 
the CVT PATENT RIGHTS or includes any of the CVT TECHNOLOGY.

    1.22 The term "RESEARCH INFORMATION" shall mean any data, results, 
formulas, process information or other information which results from the 
RESEARCH PROGRAM.

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    1.23 The term "RESEARCH INVENTION(S)" shall mean any invention, know-how, 
method, process, use, article of manufacture, or composition of matter 
conceived or first actually or constructively reduced to practice as part of 
the RESEARCH PROGRAM or which results from the RESEARCH PROGRAM.

    1.24 The term "RESEARCH MATERIAL" shall mean any material, reagent or 
substance which results from the RESEARCH PROGRAM.

    1.25 The term "RESEARCH PATENT RIGHT(S)" shall mean all patents and 
patent applications throughout the TERRITORY that claim RESEARCH INFORMATION, 
RESEARCH INVENTIONS or RESEARCH MATERIAL or any part thereof, including any 
provisional applications, substitutions, extensions, reissues, 
reexaminations, renewals, continuations, continuations-in-part, divisionals 
and supplemental protection certificates, statutory invention registrations, 
applications for statutory invention registrations, and any foreign 
equivalents thereof.

    1.26 The term "RESEARCH PLAN" shall mean the written descriptions of the 
research and development to be performed by CVT as part of the RESEARCH 
PROGRAM for the first AGREEMENT YEAR and for each subsequent AGREEMENT YEAR 
of the RESEARCH PROGRAM as approved in accordance with Section 8.2.

    1.27 The term "RESEARCH PROGRAM" shall have the meaning set forth in 
Section 8.1 of this Agreement.    

    1.28 The term "SUBLICENSE INCOME" shall mean any royalties or other 
consideration received by a party hereto from any SUBLICENSEES in respect of 
sales of PRODUCTS, excluding amounts paid to such party for research or other 
services conducted by such party, for clinical trials, for purchases of 
PRODUCTS or of other goods or products at fair market value, or for equity 
investments at fair market value in such party.

    1.29 The term "SUBLICENSEE" shall mean any non-AFFILIATE third party 
expressly licensed by BIOGEN to make, have made or formulate any PRODUCT and 
to sell the PRODUCT made or formulated.  A SUBLICENSEE shall not include a 
distributor or other party licensed to sell PRODUCT but not to make, have 
made or formulate PRODUCT.

    1.30 The term "TERRITORY" shall mean the United States, including Puerto 
Rico, Guam and all other territories of the United States, and all other 
countries and territories in North America and South America.

                                       6.

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    1.31 The term "THIRD PARTY(IES)" shall mean a person or entity who or 
which is neither a party hereto nor an AFFILIATE or SUBLICENSEE of a party 
hereto.

    1.32 The term "UFRFI LICENSE" shall mean a certain License Agreement 
dated as of June 27, 1994 by and between CVT and University of Florida 
Research Foundation, Inc. ("UFRFI"), as amended.

    1.33 The term "VALID CLAIM" shall mean (i) a claim of a pending patent 
application which claim shall not have been canceled, withdrawn, abandoned or 
rejected by an administrative agency from which no appeal can be taken and 
which application shall not have been pending for more than [  *  ] or (ii) a 
claim of an issued and unexpired patent which has not lapsed or become 
abandoned or been declared invalid or unenforceable by a court of competent 
jurisdiction or an administrative agency from which no appeal can be or is 
taken.

    1.34 The use herein of the plural shall include the singular, and the use 
of the masculine shall include the feminine.

SECTION 2.    GRANT AND OTHER RIGHTS.

    2.1  CVT hereby grants to BIOGEN and BIOGEN hereby accepts from CVT an 
exclusive, royalty-bearing right and license under the CVT TECHNOLOGY and CVT 
PATENT RIGHTS to make, have made, import, use, offer for sale and sell 
PRODUCTS in the TERRITORY.  CVT shall be responsible for paying any royalty 
obligations which CVT may have to any THIRD PARTY under agreements between 
CVT and such THIRD PARTIES in effect as of the EFFECTIVE DATE arising from 
the exercise of the license grant set forth above.

    2.2  (a)  AFFILIATES. BIOGEN shall have the full and unrestricted right 
to extend the license granted to it herein to AFFILIATES.  BIOGEN shall 
advise CVT of any such extension to AFFILIATES.

         (b)  SUBLICENSES. BIOGEN shall have the right to grant sublicenses 
in the TERRITORY under the license granted to it herein in accordance with 
the following:

    BIOGEN shall have the full and unrestricted right to grant sublicenses at 
any time after the [  *  ] for such PRODUCT, but may not grant a sublicense 
prior to that time.

    BIOGEN agrees to forward to CVT a copy of any sublicense agreements 
within thirty (30) days of the execution of such sublicense agreements and 
further agrees to 

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forward to CVT annually a copy of such reports received by BIOGEN from its 
sublicensees during the preceding twelve (12) month period under the 
sublicenses as shall be pertinent to a royalty accounting under said 
sublicense agreements.

    2.3  To the extent CVT PATENT RIGHTS or CVT TECHNOLOGY licensed to BIOGEN 
under this Agreement are rights which CVT has licensed from UFRFI under the 
UFRFI LICENSE, BIOGEN and CVT understand and agree that the rights licensed 
to BIOGEN by CVT are subject to the terms of the UFRFI LICENSE.

SECTION 3.    INTENTIONALLY OMITTED.

SECTION 4.    MANUFACTURE AND SUPPLY OF PRODUCT; CONDUCT OF CLINICAL TRIALS; 
TECHNOLOGY TRANSFER.

    4.1  PRODUCT SUPPLY.  BIOGEN and its AFFILIATES shall be responsible for 
the manufacture and supply of PRODUCT hereunder for clinical trials and 
commercial sales in the TERRITORY.  Notwithstanding the foregoing, within 
thirty (30) days of the Effective Date, CVT shall deliver to BIOGEN CVT's 
existing inventory of CVT-124 as described in Appendix C, along with copies 
of all quality control release test results and other relevant documentation 
relating to such inventory.  In addition, upon BIOGEN's request, CVT shall 
[  *  ] the manufacturing contract, dated December 2, 1996, between CVT and 
the [  *  ]

    4.2  COLLABORATION.  CVT's representatives on the OPERATING COMMITTEE 
shall work with BIOGEN to establish programs to optimize the chemical 
manufacturing process for PRODUCT.

    4.3  CLINICAL PROGRAMS.  BIOGEN will, at its sole expense, be responsible 
for the worldwide design and conduct of all pre-clinical, clinical, 
development and regulatory work under this Agreement for PRODUCTS being 
developed for sale hereunder and under the BML AGREEMENT, with input from CVT 
through its representation on the OPERATING COMMITTEE and the Strategy 
Committee. Notwithstanding the foregoing, CVT shall lead the protocol design 
and selection of key investigators for the following clinical studies which 
are in the planning stages as of the Effective Date, subject to BIOGEN's 
guidance and right of final approval:

         (i)  Phase II clinical trial of intravenous CVT-124 for [  *  ]

         (ii)  Phase II clinical trial of intravenous CVT-124 for protection 
against [  *  ] at BIOGEN's option; and

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         (iii)  Phase I [  *  ] study.

    Protocols for the above clinical trials shall be approved by the 
OPERATING COMMITTEE, as defined below, as soon as possible after the 
Effective Date.

    4.4  TRANSFER OF CVT TECHNOLOGY.  From and after the Effective Date, CVT 
shall make available sufficient personnel and resources to accomplish the 
swift and orderly transfer of copies and/or samples, as the case may be, of 
all CVT Technology to Biogen.

    4.5  [  *  ] REGULATORY FILINGS.  CVT [  *  ] all INDs and other regulatory
filings relating to CVT-124.  CVT shall promptly deliver copies of such 
filings to BIOGEN and [  *  ] of such filings.  CVT and BIOGEN shall 
cooperate in [  *  ] in such a way as not to harm either CVT's or BIOGEN's 
relationship with the relevant regulatory authorities.  To that end, BIOGEN 
may elect to have one or more of CVT's employees participate in meetings 
between BIOGEN and regulatory authorities [  *  ] CVT's regulatory filings.  

    4.6  CLINICAL CONTRACTS, TRANSFER OF CLINICAL DATABASE. The transition of 
planning for the conduct of planned clinical trials of CVT-124 shall proceed 
in accordance with Appendix B.  If BIOGEN elects to enter into contracts with 
the parties with whom CVT has been negotiating, whether or not upon the terms 
previously negotiated by CVT, CVT shall provide its full cooperation, as 
requested by BIOGEN.  CVT shall, within five (5) days after the EFFECTIVE 
DATE, provide BIOGEN with a full and complete copy, including all raw data, 
of [  *  ] In addition, upon BIOGEN's request, CVT shall provide to BIOGEN 
all of the original Case Report Forms from  such study.

SECTION 5.    DUE DILIGENCE.

    5.1  PRODUCT DEVELOPMENT.  BIOGEN shall use commercially reasonable 
efforts to develop and market a PRODUCT, which efforts shall be at least 
commensurate with those efforts undertaken in BIOGEN's own internal programs 
with the same profit potential and risk.  

    5.2  [  *  ]  BIOGEN shall use commercially reasonable efforts 
to develop a PRODUCT for [  *  ] which efforts shall be at least 
commensurate with those efforts undertaken in BIOGEN's own internal programs 
with the same profit potential and risk.  Subject to technical and regulatory 
delays, BIOGEN will use commercially reasonable efforts to meet the following 
development timeline:

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         (I)   Within [  *  ] of the successful completion of a [  *  ] BIOGEN 
shall [  *  ]

         (II)  Within [  *  ] of commencing [  *  ] BIOGEN shall commence  a 
Phase I trial of such PRODUCT; and

         (III) Within [  *  ] of the successful completion of [  *  ] 
BIOGEN shall make its decision to commence a [  *  ] of such PRODUCT.

    Provided that BIOGEN has used commercially reasonable efforts as 
aforesaid, failure to meet the foregoing timeline shall not constitute a 
breach of this Agreement, or result in any limitation on the licenses and 
rights granted to BIOGEN pursuant to this Agreement.

    5.3  STATUS REPORTS.  Within sixty (60) days of the end of each calendar 
year during the term hereof, BIOGEN shall provide to CVT a written report 
summarizing the status of BIOGEN's development efforts hereunder and the 
results of the prior year's efforts.

SECTION 6.    CONFIDENTIALITY AND INFORMATION.

    6.1  During the term of this Agreement, it is contemplated that each 
party may disclose to the other, proprietary and confidential technology, 
inventions, technical information, material, reagents, biological materials 
and the like which are owned or controlled by the party providing such 
information or which that party is obligated to maintain in confidence 
("Confidential Information"). Each party shall have the right to refuse to 
accept the other party's Confidential Information.  Each party agrees not to 
disclose and to maintain the Confidential Information of the other party in 
strict confidence, to cause all of its agents, representatives and employees 
to maintain the disclosing party's Confidential Information in confidence and 
not to disclose any such Confidential Information to a third party without 
the prior written consent of the disclosing party and not to use such 
Confidential Information for any purpose other than as licensed under this 
Agreement.

    6.2  The obligations of confidentiality will not apply to information 
which:

         (i)  was known to the receiving party or generally known to the 
public prior to its disclosure hereunder through no fault of the receiving 
party or any agent, representative or employee thereof; or

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         (ii)  subsequently becomes known to the public by some means other 
than a breach of this Agreement, including publication and/or laying open to 
inspection of any patent applications or patents;

         (iii)  is subsequently disclosed to the receiving party by a third 
party having a lawful right to make such disclosure and who is not under an 
obligation of confidentiality to the disclosing party;

         (iv)  is approved for release by the parties. 

    6.3  The obligations of Section 6.1 notwithstanding, BIOGEN may disclose 
the Confidential Information of CVT licensed to BIOGEN hereunder (a) to 
SUBLICENSEES and (b) to THIRD PARTIES who (i) need to know the same in order 
to secure regulatory approval for the sale of PRODUCT, (ii) who need to know 
the same in order to work towards the commercial development of PRODUCT or to 
manufacture PRODUCT, or (iii) who are approved by CVT, provided that such 
parties, other than regulatory authorities, are bound by obligations of 
confidentiality and non-use at least as stringent as those set forth herein. 
Further, either party may disclose Confidential Information of the other 
party to the extent such disclosure is required by law, rule, regulation or 
bona fide legal process to be disclosed, provided that the receiving party 
takes all reasonable steps to restrict and maintain confidentiality of such 
disclosure and provides reasonable notice to the disclosing party.

    6.4  CVT shall provide to BIOGEN, or if required to the applicable 
regulatory authority, all documents and information, to the extent in CVT's 
possession or otherwise reasonably accessible to CVT with the right to 
disclose, requested by the regulatory authority or reasonably requested by 
BIOGEN in support of BIOGEN's regulatory submissions.  Copies of all 
documents provided directly to a regulatory authority shall be provided to 
BIOGEN in advance, if practicable, or otherwise within [  *  ] of 
delivery to the regulatory authority.  In addition, CVT shall provide to 
BIOGEN any information, to the extent in CVT's possession or otherwise 
reasonably accessible to CVT with the right to disclose, related to PRODUCT 
that is (a) reasonably required in support of BIOGEN's applications to patent 
offices and such governmental offices as regulate the price of PRODUCT and/or 
(b) reasonably required to support a legal action by BIOGEN against a THIRD 
PARTY.

    6.5  Neither party may disclose the existence or terms of this Agreement
without the prior written consent of the other party; provided, however, that
either party may make such disclosure to the extent required by law.   The
parties have approved an initial press release as set forth in APPENDIX D
attached hereto.  Once any written statement is approved for disclosure by both
parties, either party may make 

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subsequent public disclosure of the contents of such statement without the 
further approval of the other party.

SECTION 7.    GOVERNANCE.

    7.1  OVERALL RESPONSIBILITY.

         (a)  Overall direction of the parties' strategic alliance under this 
Agreement and the BML AGREEMENT will be provided by an Oversight Committee 
consisting of an equal number of senior management representatives from each 
party.  The Oversight Committee will meet on an ad hoc basis during the term 
of this Agreement to monitor the overall performance of the collaboration 
hereunder and to resolve any disputes which may arise regarding the operation 
of the collaboration, such resolution to be within a reasonable period of 
time under the relevant circumstances, in any event not to exceed [  *  ]

         (b)  The following committees shall also be established under this 
Agreement as set forth below.  

              (i)  the OPERATING COMMITTEE; and

              (ii) the Strategy Committee.

    7.2  OPERATING COMMITTEE.  An OPERATING COMMITTEE (a/k/a, the "CVT-124 
Development Team") shall be established by BIOGEN to manage the worldwide 
development of PRODUCTS.  The activities of the RESEARCH PROGRAM, described 
hereinafter in Section 8, will also be overseen and monitored by the 
OPERATING COMMITTEE.

         (a)  MEMBERSHIP.  Within ten (10) days of the date hereof, CVT shall 
designate up to [  *  ] representatives to serve on the OPERATING COMMITTEE. 
Additional representatives of CVT may attend OPERATING COMMITTEE meetings on 
an as needed basis with the prior approval of BIOGEN, such approval not to be 
unreasonably withheld.  CVT will have the right to change its representation 
on the OPERATING COMMITTEE upon written notice to BIOGEN.  BIOGEN 
representatives on the OPERATING COMMITTEE shall include representatives of 
all relevant line functions, as determined by BIOGEN.

         (b)  CHAIR.  The OPERATING COMMITTEE chair (a/k/a "Program 
Executive") shall be designated by BIOGEN.

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         (c)  RESPONSIBILITIES.  The OPERATING COMMITTEE will have authority to
take and perform all actions necessary to accomplish its responsibilities,
including but not limited to, authority to:

              (i)  oversee and manage the day-to-day development of PRODUCTS;

              (ii) oversee the RESEARCH PROGRAM, and monitor performance
thereunder;

              (iii)     coordinate programs to optimize the chemical
manufacturing process;

              (iv) review and propose RESEARCH PLANS and budgets; and

              (v)  review any and all proposed publications or communications
relating to the RESEARCH PROGRAM and the results therefrom, in accordance with
the procedure set forth in Section 8.

         (d)  MEETINGS.  The OPERATING COMMITTEE will meet not less than
monthly.  Meetings will be held at BIOGEN's premises or such other place as may
be mutually agreed upon.  CVT representatives may participate in person or by
telephone.  In the event of disagreement, [  *  ]

    7.3  STRATEGY COMMITTEE.  A Strategy Committee will be established which 
will meet as needed to set worldwide clinical, regulatory and marketing 
strategies for PRODUCTS.  CVT may designate up to four (4)  representatives 
who may participate in meetings of the Strategy Committee in person or by 
telephone. Additional representatives of CVT may attend Strategy Committee 
meetings on an as needed basis with the prior approval of BIOGEN, such 
approval not to be unreasonably withheld.  In the event of disagreement, 
[  *  ]

SECTION 8.    RESEARCH PROGRAM.

    8.1  OBJECT.  CVT shall conduct a program of research in accordance with 
annual RESEARCH PLANS established in accordance with Section 8.2 (the 
"RESEARCH PROGRAM").  The objectives of the RESEARCH PROGRAM shall be first 
to [  *  ] of CVT-124, and thereafter to explore [  *  ] CVT-124, to 
identify [  *  ] CVT agrees to conduct and manage

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                                       13.

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the RESEARCH PROGRAM pursuant to the RESEARCH PLAN and BIOGEN agrees to support 
such RESEARCH PROGRAM at CVT in accordance with the terms and conditions set
forth below.  

    8.2  (a)  DEFINITION OF PHASES OF RESEARCH PROGRAM.   The RESEARCH 
PROGRAM shall be divided into two phases.  Phase 1 of the RESEARCH PROGRAM 
shall begin with the EFFECTIVE DATE and end at such time that a [  *  ] by 
either party.  Phase 2 of the RESEARCH PROGRAM shall commence after the 
completion of Phase 1 and continue for as long as the RESEARCH PROGRAM is in 
effect.

         (b)  CONDUCT OF PHASE 1 OF  THE RESEARCH PROGRAM.  The RESEARCH PLAN 
and budget for Phase 1 of the RESEARCH PROGRAM is attached hereto as Appendix 
E. CVT will use commercially  reasonable  efforts to perform the RESEARCH 
PLAN for Phase 1 of  the RESEARCH PROGRAM in accordance with the agreed-upon 
schedule and budget contained in Appendix E.  Such budget includes the number 
of FTEs to be devoted to the RESEARCH PROGRAM during each  AGREEMENT YEAR 
during Phase 1 (at [  *  ] per FTE), together with a breakdown of any other 
fees and expenses to be incurred, and totals [  *  ] per year.

         (c)  CONDUCT OF PHASE 2 OF  THE RESEARCH PROGRAM.    The RESEARCH 
PLAN and budget for Phase 2 of the RESEARCH PROGRAM shall be approved by the 
parties at least ninety (90) days prior to the beginning of Phase 2 and at 
least ninety (90) days prior to the beginning of each AGREEMENT YEAR 
commencing during Phase 2.  CVT will use commercially reasonable  efforts to 
perform the RESEARCH PLAN during Phase 2 of the RESEARCH PROGRAM in 
accordance with the agreed-upon schedule and budget.

         (d)  EXCHANGE OF INFORMATION AND REPORTS.  To further the efforts of 
the parties under this Agreement, CVT shall promptly disclose to BIOGEN any 
RESEARCH INVENTIONS arising out of the RESEARCH PROGRAM, but in any event 
within [  *  ] for potentially patentable, significant RESEARCH INVENTIONS, 
and within [  *  ] of the end of each CALENDAR QUARTER for all others. CVT 
shall keep BIOGEN and the OPERATING COMMITTEE reasonably informed of its 
progress in the RESEARCH PROGRAM and shall deliver reasonably detailed 
written progress reports to BIOGEN semi-annually.

         (e)  VISITATION.  For the purpose of facilitating the parties 
understanding of the research and development activities conducted hereunder, 
CVT will permit duly authorized employees or representatives of BIOGEN to 
visit its facilities where the 

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                                       14.

<PAGE>

RESEARCH PROGRAM activities are conducted, at reasonable times and with 
reasonable notice, subject to appropriate confidentiality provisions.

    8.3  SOURCE OF FUNDS.  During the term of the RESEARCH PROGRAM  as 
specified in Section 8.5, CVT will dedicate [  *  ]
in each AGREEMENT YEAR from the proceeds of BML's equity investments in CVT 
to be made pursuant to the BML AGREEMENT to support the conduct of the 
RESEARCH PROGRAM at CVT.  Such funds shall be utilized solely for performance 
of the RESEARCH PROGRAM in accordance with the approved budget.

    8.4  REPORTS [  *  ].  During Phase 1 of the RESEARCH PROGRAM, CVT shall 
prepare annual financial reports of actual and budgeted expenditures under 
the RESEARCH PROGRAM.  BIOGEN [  *  ] provided under the BML AGREEMENT for 
Phase 1 of the RESEARCH PROGRAM in accordance with the approved budget.  The 
[  *  ] in any report from CVT, in which case [  *  ]

    8.5  TERM AND TERMINATION OF THE RESEARCH PROGRAM.  The term of the 
RESEARCH PROGRAM will be the first three (3) AGREEMENT YEARS.  BIOGEN shall 
be entitled to terminate the RESEARCH PROGRAM and BML shall be entitled to 
cease funding thereof in the event of termination of this Agreement or in the 
event of a breach by CVT of any of CVT's material obligations in the RESEARCH 
PROGRAM following written notice of such breach to CVT.  If such breach is 
not cured within [  *  ] after written notice is given by BIOGEN to CVT 
specifying the breach, BIOGEN may terminate the RESEARCH PROGRAM without 
terminating the entire Agreement and BML may cease funding of the RESEARCH 
PROGRAM  forthwith upon written notice to CVT after expiration of such [  *  ]
In the event BIOGEN terminates the RESEARCH PROGRAM as provided above, BIOGEN 
may, at its option, require CVT to repurchase from BML shares of CVT Common 
Stock sold to BML pursuant to the BML AGREEMENT, [  *  ] in an amount equal 
to [  *  ] less the amount of CVT's actual expenditures incurred during the 
AGREEMENT YEAR prior to such termination of the RESEARCH PROGRAM.  In 
addition to BIOGEN's right to terminate the RESEARCH PROGRAM for breach as 
provided above, either BIOGEN or CVT may terminate the RESEARCH PROGRAM 
without terminating the entire Agreement upon [  *  ] written notice 
delivered prior to the commencement of the second AGREEMENT YEAR or the third 
AGREEMENT YEAR; provided, however, that notwithstanding the foregoing, CVT 
may not terminate the RESEARCH  PROGRAM prior to the end of Phase 1 of the 
RESEARCH PROGRAM.

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                                       15.

<PAGE>

    8.6  THIRD PARTY SUPPORT  CVT shall not apply any of the funding provided 
by BML under the BML AGREEMENT for Phase 1 of the RESEARCH PROGRAM  towards 
R&D to be conducted in whole or in part by a THIRD PARTY without BIOGEN's 
approval, such approval not to be unreasonably withheld or delayed.  CVT may 
apply any of the funding provided by BML under the BML AGREEMENT for Phase 2 
of the RESEARCH PROGRAM towards R&D to be conducted in whole or in party by a 
THIRD PARTY provided that BIOGEN has approved in advance the form of 
agreement to be used in contracting with such THIRD PARTY, such approval not 
to be unreasonably withheld or delayed.

    8.7  CONFIDENTIALITY.  In order to facilitate the operation of the 
RESEARCH PROGRAM, either party may disclose confidential or proprietary 
information owned or controlled by it to the other.  It is hereby understood 
and agreed that such information shall be treated in accordance with Section 
6 hereof.

    8.8  RESULTS OF THE RESEARCH PROGRAM.

         (a)  All right, title and interest in and to any RESEARCH 
INFORMATION, RESEARCH INVENTIONS and RESEARCH MATERIAL (the "RESULTS"), and 
any RESEARCH PATENT RIGHTS based thereon, conceived and reduced to practice 
solely by employees or agents of CVT shall be owned solely by CVT ("CVT 
RESULTS"), subject to the licenses granted to BIOGEN under Section 2 hereof 
and the licenses granted to BML under Section 2 of the BML AGREEMENT.  All 
right, title and interest in or to any RESULTS and any RESEARCH PATENT RIGHTS 
based thereon, conceived and reduced to practice solely by employees or 
agents of BIOGEN shall be owned solely by BIOGEN.  All right, title and 
interest in and to any RESULTS and any RESEARCH PATENT RIGHTS based thereon 
conceived and reduced to practice by employees or agents of CVT and employees 
or agents of BIOGEN shall be owned jointly by CVT and BIOGEN ("JOINT 
RESULTS"), with CVT's ownership interest therein being subject to the 
licenses granted to BIOGEN under Section 2 hereof and the licenses granted to 
BML under Section 2 of the BML AGREEMENT. Invention, conception and reduction 
to practice of RESEARCH INVENTIONS, RESEARCH INFORMATION, RESEARCH MATERIALS, 
and RESEARCH PATENT RIGHTS shall be determined in accordance with United 
States intellectual property laws.

         (b)  There will be no publication of the RESULTS by CVT, or any 
employee of CVT unless the OPERATING COMMITTEE has reviewed the proposed 
scientific publication concerning the RESULTS and each party has consented in 
writing to the publication, which review shall be conducted within [  *  ] of 
submission of the proposed publication to the OPERATING COMMITTEE, and which 
approval shall not be unreasonably withheld or delayed.  CVT will, upon 
request of 

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                                       16.

<PAGE>

BIOGEN, delay publication for up to [  *  ] to allow for the filing 
of patent applications incorporating RESULTS.

         (c)  Notwithstanding any provision in this Agreement and/or the BML 
AGREEMENT to the contrary, BIOGEN shall have no rights pursuant to Section 2 
hereof, and BML shall have no rights pursuant to Section 2 of the BML 
AGREEMENT to any compounds developed in the RESEARCH PROGRAM that are not 
Adenosine A(1) Antagonists ("Non- A(1) Compounds").  With respect to such 
Non- A(1) Compounds, BIOGEN shall have a right of first refusal as follows: 
CVT shall give written notice to BIOGEN specifying in reasonable detail the 
rights and data, including preclinical data establishing IN VIVO activity,  
relating to Non-A(1) Compounds that CVT has developed (the "Offer").  BIOGEN 
shall have [  *  ] after the date of the Offer to provide a written response 
to CVT (the "Response") as to whether or not BIOGEN wishes to enter into 
negotiations with  CVT with respect to such rights.  If the Response states 
that BIOGEN wishes to enter into negotiations with CVT, the parties shall 
negotiate in good faith the licensing of such rights for a period of [  *  ] 
from the date of the Response. If BIOGEN declines to enter into negotiations 
or if the parties do not agree upon and execute a written agreement within 
the [  *  ] negotiation period, CVT shall deliver to BIOGEN in writing its 
last best offer for licensing such rights.  BIOGEN shall have [  *  ] from 
receipt of CVT's last best offer to accept such offer in writing.  If BIOGEN 
declines to accept CVT's last best offer, CVT shall thereafter have the right 
to negotiate with third parties with respect to such rights; provided, 
however, that the terms of any such definitive agreement with any third party 
shall not be more favorable to the third party than CVT's last best offer to 
BIOGEN.  The foregoing BIOGEN rights shall terminate [  *  ] after the end of 
the RESEARCH PROGRAM.

SECTION 9.    PATENTS.

    9.1  (a)  CVT shall promptly advise BIOGEN, in writing, of each potentially
patentable or otherwise potentially useful RESEARCH INVENTION arising from the
RESEARCH PROGRAM.  Representatives of CVT and BIOGEN shall then discuss whether
a patent application or applications pertaining to such RESEARCH INVENTION
should be filed and in which countries.  The titles, serial numbers and other
identifying data of patent applications claiming a RESEARCH INVENTION to which
BIOGEN is granted rights hereunder and filed after the EFFECTIVE DATE by mutual
agreement of CVT and BIOGEN, or by BIOGEN alone pursuant to the last sentence of
this section or pursuant to subsection (c) hereof, shall be added to APPENDIX A
of this Agreement and to Appendix A of the BML AGREEMENT and CVT's interest
therein shall become CVT PATENT RIGHTS for purposes of both this Agreement and
the BML AGREEMENT. CVT shall file, prosecute and maintain patent applications
and patents worldwide relating to such CVT RESULTS as the parties agree

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                                       17.

<PAGE>

hereunder, [  *  ] through patent counsel selected by CVT and reasonably 
acceptable to BIOGEN, except  as provided in subsection (c) below. BIOGEN 
shall have the opportunity to provide substantive review and comment on any 
such filing, prosecution and or maintenance and the rights as set forth in 
Section 9.2 below.  In the event CVT declines to prepare, file, prosecute or 
maintain a patent application on a RESEARCH INVENTION, then BIOGEN may 
prepare, file, prosecute and maintain such patent application, in which 
events [  *  ] after the date of its election to assume responsibility for 
such patent application.

         (b)  BIOGEN shall, as of the EFFECTIVE DATE, assume responsibility 
to prepare, file, prosecute and maintain patent applications and patents 
worldwide relating to CVT PATENT RIGHTS identified on Appendix A as of the 
EFFECTIVE DATE and relating to JOINT RESULTS,  and [  *  ] related thereto.  
Notwithstanding the foregoing, CVT shall maintain CVT PATENT RIGHTS for a 
period of 6 weeks from the EFFECTIVE DATE and shall cooperate fully in the 
orderly transfer to BIOGEN's patent counsel of all files and necessary powers 
of attorney related to such CVT PATENT RIGHTS within 4 weeks from the 
EFFECTIVE DATE.  BIOGEN shall also have the option pursuant to subsection (a) 
above to prepare, file, prosecute and maintain patent applications and 
patents worldwide relating to CVT RESULTS that CVT declines to file, 
prosecute and/or maintain, and shall have the option under subsection (c) 
below.

         (c)  BIOGEN shall have the option, commencing at such time as a 
PRODUCT to which RESEARCH PATENT RIGHTS relate enters human clinical trials, 
to assume CVT's responsibility to file, prosecute and maintain patent 
applications and patents worldwide relating to such RESEARCH PATENT RIGHTS in 
which events [  *  ] after the date of its election to assume control of such 
RESEARCH PATENT RIGHTS.

         (d)   The term "Patent Costs" shall mean all reasonable [  *  ] 
incurred for the filing, prosecution, issuance, and maintenance of the 
identified CVT PATENT RIGHTS, but not including the costs of any opposition 
or interference proceedings, which shall [  *  ] BIOGEN shall use patent 
counsel selected by BIOGEN and reasonably acceptable to CVT.  CVT shall have 
the opportunity to provide substantive review and comment on any such filing, 
prosecution and or maintenance and the rights as set forth in Section 9.2 
below.

         (e)  Notwithstanding anything in this Section 9.1 to the contrary, 
BIOGEN may, at its discretion, elect to discontinue financial support of any 
patent 

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                                       18.

<PAGE>

application for which it is providing support under this Agreement, provided, 
however, that BIOGEN will notify CVT of its intention at least sixty (60) 
days prior to taking such action.  In any country in which BIOGEN has elected 
to discontinue its support of any patent application, CVT, upon receiving 
notice, may elect at its own expense to assume all financial responsibility 
for the prosecution of such patent application; provided, however, that if 
CVT obtains issuance of any such patent application, BIOGEN shall reimburse 
CVT for such expenses.  BIOGEN's determination to [  *  ] with respect to such 
patent application pursuant to [  *  ] hereof or pursuant to [  *  ] of the 
BML AGREEMENT.  

    9.2  With respect to any CVT PATENT RIGHTS, all substantive communication 
to or from the United States Patent and Trademark Office or its equivalent in 
any other jurisdiction, including, but not limited to, each patent 
application, office action, response to office action, amendment, 
restriction, election, request for terminal disclaimer, and request for 
reissue or reexamination of any patent issuing from such application, as well 
as any intention to discontinue prosecution or financial support of any 
patent or patent applications shall be provided to BIOGEN or CVT, as the case 
may be, by the party controlling the prosecution or maintenance sufficiently 
prior to the filing of such document to allow for review and comment by 
BIOGEN or CVT, respectively.  However, BIOGEN and CVT shall have the right to 
take any  action that in its judgment is necessary to preserve such CVT 
PATENT RIGHTS for which it is responsible.  Both parties shall cooperate 
fully to facilitate the preparation, filing, prosecution and maintenance of 
CVT PATENT RIGHTS.  Notwithstanding anything herein to the contrary, neither 
BIOGEN nor CVT shall abandon a CVT PATENT RIGHT or allow a CVT PATENT RIGHT 
to lapse without first giving the other notice of such intention at least 
[  *  ] prior to the date on which such CVT PATENT RIGHT will lapse or become 
abandoned.  BIOGEN or CVT shall have the right to assume the prosecution, 
maintenance and defense of any CVT PATENT RIGHT which the other intends to 
abandon.  If this Agreement terminates for any reason, BIOGEN shall 
immediately thereafter transfer to CVT control of the prosecution and 
maintenance of all CVT PATENT RIGHTS and original copies of all documents 
relating to such CVT PATENT RIGHTS in the possession or control of BIOGEN.

    9.3  (a)  If any of the CVT PATENT RIGHTS under which BIOGEN is licensed 
hereunder, or under which BML is licensed under the BML AGREEMENT,  is 
infringed by a THIRD PARTY's manufacture, import, use, sale or offer to sell 
of CVT-124 or another Adenosine A(1) Antagonist, or a product comprising or 
containing CVT or another Adenosine A(1) Antagonist, BIOGEN shall have the 
right and option but not the obligation to bring an action for infringement, 
at its sole expense, against such THIRD PARTY in the name of CVT or its 
licensors and/or in the name of BIOGEN, 

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                                       19.

<PAGE>

and to join CVT or its licensors, at BIOGEN's expense,  as a party plaintiff 
if required or if it would promote the success of the litigation. Each party 
shall promptly notify the other party of any such infringement. BIOGEN shall 
keep CVT informed as to the prosecution of any action for such infringement.  
No settlement, consent judgment or other voluntary final disposition of the 
suit which adversely affects CVT PATENT RIGHTS may be entered into without 
the consent of CVT, which consent shall not unreasonably be withheld.

         (b)  In the event that BIOGEN shall undertake the enforcement and/or 
defense of the CVT PATENT RIGHTS by litigation as provided above any recovery 
of damages by BIOGEN for any such suit shall be applied first in satisfaction 
of any unreimbursed expenses and legal fees of BIOGEN relating to the suit.  
The balance remaining from any such recovery shall [  *  ] considering where 
the infringing sales were made.

         (c)  In the event that, and only if, BIOGEN specifically elects not 
to pursue an action for infringement, CVT (or its licensor) shall have the 
right and option, but not the obligation at its cost and expense to initiate 
infringement litigation and [  *  ]

         (d)  In any infringement suit either party may institute to enforce 
the CVT PATENT RIGHTS pursuant to this Agreement, the other party hereto 
shall, at the request of the party initiating such suit, cooperate in all 
respects and, to the extent possible, have its employees testify when 
requested and make available relevant records, papers, information, samples, 
specimens, and the like.  All reasonable out-of-pocket costs incurred in 
connection with rendering cooperation requested hereunder shall be paid by 
the party requesting cooperation.

SECTION 10.   COMPENSATION.

    10.1 (a)  As consideration for research and development already performed 
by CVT with respect to PRODUCTS, upon execution of this Agreement, BIOGEN 
shall pay to CVT a non-creditable, non-refundable payment in the amount of 
Five Million Dollars ($5,000,000).

         (b)  Upon execution of this Agreement, BIOGEN shall pre-pay the 
[  *  ] required to be paid upon the successful completion of a [  *  ] 
pursuant to Section 10.3(a)(ii).  In the event the planned [  *  ] of CVT-124 
is unsuccessful [  *  ] Biogen shall notify CVT in writing, whereupon CVT 
shall refund to Biogen such pre-paid milestone within 

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                                       20.

<PAGE>

thirty (30) days.  If Biogen shall thereafter successfully complete a [  *  ] 
with another PRODUCT, Biogen shall pay the milestone as provided in Section 
10.3(a)(ii).

    10.2 (a)  BIOGEN shall pay to CVT royalties on NET SALES of PRODUCTS in the
TERRITORY ("Royalties") as follows: 

              (i)  Royalties payable to CVT on NET SALES of PRODUCTS in the 
TERRITORY shall be [  *  ] and determined based on worldwide annual NET 
SALES (i.e., including NET SALES of PRODUCTS under the BML AGREEMENT) in each 
calendar year in accordance with the following table:

      [  *  ]  Annual Net Sales        Royalty
    ------------------------------------------
    Up to [  *  ] Million              [  *  ]

    [  *  ] Million to [  *  ] Million [  *  ]

    Over [  *  ] Million               [  *  ]

              (ii) Notwithstanding subparagraph (i) above, in the event there 
are two consecutive twelve month periods in which worldwide NET SALES exceed 
[  *  ] Million but are less than [  *  ] Million, then, unless subparagraph 
(iii) applies, Royalties shall thereafter be determined based on annual 
worldwide NET SALES in any subsequent calendar year in accordance with the 
following table:

      [  *  ]  Annual Net Sales        Royalty
    ------------------------------------------
    Up to [  *  ] Million              [  *  ]

    [  *  ] Million to [  *  ] Million [  *  ]

              (iii) Notwithstanding subparagraph (ii), if at any time after 
paragraph (ii) applies worldwide NET SALES exceed [  *  ] Million for one 
full twelve month period or are less than [  *  ] Million for one full twelve 
month period, the Royalties owed on NET SALES shall thereafter be determined 
in accordance with subparagraph (i), regardless of the subsequent annual 
overall levels of NET SALES.

              (iv) Royalties shall be payable under this Agreement solely for 
PRODUCT sold in the TERRITORY.  However, for the purposes of determining the 
applicable [  *  ] royalty rate, worldwide annual NET SALES shall be deemed 
to include NET SALES under both this Agreement and the BML AGREEMENT.

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                                       21.

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         (b)  Notwithstanding the foregoing, if the use or sale of PRODUCT by 
BIOGEN or its AFFILIATES in the country in which the PRODUCT is sold is not 
covered by a VALID CLAIM of a CVT PATENT RIGHT in such country, the Royalties 
payable with respect to NET SALES in such country shall be  [  *  ] of the 
amounts otherwise due pursuant to Section 10.2(a) above; PROVIDED, however, 
that if, in any such country, any one or more THIRD PARTY(S)  is/are selling 
a generic version of the PRODUCT being sold by BIOGEN or its AFFILIATES and 
such THIRD PARTY(S)' sales of such generic product exceeds [  *  ] of 
BIOGEN's sales of the PRODUCT in such country, the Royalties in such country 
shall be reduced to [  *  ] during such period of generic sales.

         (c)  The obligation to pay Royalties for each PRODUCT shall continue 
on a country-by-country and product-by-product basis until the last to expire 
VALID CLAIM of the CVT PATENT RIGHTS in such country covering such PRODUCT; 
provided, however, that in any country in which there is no such VALID CLAIM, 
the obligation to pay Royalties shall continue only until the expiration of 
[  *  ] from the FIRST COMMERCIAL SALE of such PRODUCT in such country 
by BIOGEN or its AFFILIATES or SUBLICENSEES.

         (d)  (i)  In the event that after the EFFECTIVE DATE BIOGEN becomes 
obligated to pay any royalties or other sums to THIRD PARTIES because the 
manufacture, use or sale of CVT-124 or another Adenosine A(1) Antagonist 
contained in a PRODUCT sold by BIOGEN hereunder in the TERRITORY infringes 
such THIRD PARTIES' intellectual property  rights, then BIOGEN shall be 
entitled to credit [  *  ] of any such obligations against 
Royalties due to CVT pursuant to this Section 10.2.

              (ii) In the event that after the EFFECTIVE DATE BIOGEN becomes 
obligated to pay any royalties or other sums to THIRD PARTIES because the 
manufacture, use or sale of a PRODUCT sold by BIOGEN hereunder in the 
TERRITORY infringes such THIRD PARTIES' intellectual property  rights on 
account of a fact other than [  *  ] then the matter shall be referred to the 
Oversight Committee to determine in good faith whether or not BIOGEN shall be 
entitled to a credit of up to [  *  ] of any such obligations against 
Royalties due to CVT pursuant to this Section 10.2.  In the event the 
Oversight Committee cannot agree within forty-five (45) days after referral 
of the matter to them for resolution, then the [  *  ] representatives to the 
Oversight Committee shall [  *  ]

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              (iii)  In no event shall any credits under subsections (d)(i) 
and (d)(ii), or any cost-sharing pursuant to subsection (e) below, reduce 
Royalties payable to CVT hereunder for any CALENDAR QUARTER by more than [  *  ]
of the amounts otherwise due.  [  *  ]

         (e)  In the event that [  *  ] of CVT-124 identified during Phase 1 
of the RESEARCH PROGRAM results in [  *  ] (including, but not limited to, 
any cost to BIOGEN of [  *  ] as compared to what it would have been using 
[  *  ] CVT-124 in the [  *  ] BIOGEN and CVT agree to negotiate a [  *  ] and 
[  *  ] to reflect a [  *  ]  BIOGEN may initiate any such negotiation by 
delivering a written notice  to CVT, whereupon the relevant representatives 
of the parties on the OPERATING COMMITTEE parties shall meet and negotiate a 
reduction as aforesaid in good faith.  In the event the OPERATING COMMITTEE 
representatives  cannot agree within thirty (30) days of delivery of such 
notice by BIOGEN, the matter shall be referred to the OVERSIGHT COMMITTEE for 
resolution.    In the event the representatives to the OVERSIGHT COMMITTEE 
cannot agree within fifteen (15) days of referral of the matter to them for 
resolution, the matter shall be submitted to binding arbitration pursuant to 
the provisions of Appendix F hereof.  

         (f)  NET SALES of PRODUCT in a country in the TERRITORY for which 
BIOGEN has no royalty obligation, pursuant to Section 10.2(c), shall not be 
included in the calculation of the level of NET SALES for purposes of Section 
10.2(a).      

         (g)  In addition to the foregoing, CVT shall receive a percentage of 
BIOGEN's SUBLICENSE INCOME in accordance with this subsection (g).  

              (i)  In MAJOR MARKET countries, CVT shall receive [  *  ] of 
SUBLICENSE INCOME, subject to the following floors and cap.  For sublicenses 
executed prior to the [  *  ] in no event shall CVT receive less than [  *  ] 
of net sales of SUBLICENSEES (calculated using the NET SALES definition) for 
any PRODUCTS covered by a VALID CLAIM of CVT PATENT RIGHTS in the country in 
which they are sold.  For sublicenses executed after [  *  ] for such 
PRODUCT, in no event shall CVT receive pursuant to this 

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                                       23.

<PAGE>

subsection less than [  *  ] of net sales of SUBLICENSEES (calculated using the
NET SALES definition) for any PRODUCTS covered by a VALID CLAIM of CVT PATENT 
RIGHTS in the country in which they are sold.  Notwithstanding the foregoing, 
if the use or sale of PRODUCT by a SUBLICENSEE in the country in which the 
PRODUCT is sold is not covered by a VALID CLAIM of a CVT PATENT RIGHT in such 
country, the minimum percentages set forth in the previous two sentences 
shall be [  *  ] respectively.  In no event shall CVT receive pursuant to 
this subsection an amount greater than the Royalties which would have been 
due pursuant to this Section 10.2 on NET SALES of SUBLICENSEES if such NET 
SALES had been made by BIOGEN.

              (ii) In non-MAJOR MARKET countries, CVT shall receive [  *  ] 
of SUBLICENSE INCOME, subject to the following floors and cap.  In no event 
shall CVT receive pursuant to this subsection less than [  *  ] of net sales 
of SUBLICENSEES (calculated using the NET SALES definition) for any PRODUCTS 
covered by a VALID CLAIM of CVT PATENT RIGHTS in the country in which they 
are sold.  Notwithstanding the foregoing, if the use or sale of PRODUCT by a 
SUBLICENSEE in the country in which the PRODUCT is sold is not covered by a 
VALID CLAIM of a CVT PATENT RIGHT in such country, the minimum percentage set 
forth in the previous sentence shall be [  *  ] In no event shall CVT receive 
pursuant to this subsection an amount greater than the Royalties which would 
have been due pursuant to this Section 10.2 on NET SALES of SUBLICENSEES if 
such NET SALES had been made by BIOGEN.

         (h)  CVT hereby grants BIOGEN the right to [  *  ] on sales of 
PRODUCT by BIOGEN, BML, their AFFILIATES and SUBLICENSEES; provided that if 
CVT also desires to [  *  ] BIOGEN and CVT shall [  *  ] In the event BIOGEN is 
successful in [  *  ] on such sales, the royalties otherwise payable by 
BIOGEN to CVT hereunder, and the royalties otherwise payable by BML to CVT 
under the BML AGREEMENT, shall be [  *  ] and the royalties otherwise payable 
by CVT to BIOGEN pursuant to Section 14.8 hereof, and by CVT to BML pursuant 
to the corresponding provision of the BML AGREEMENT, shall be [  *  ] 
provided that CVT shall share in the benefits of any such [  *  ] in an 
amount commensurate with [  *  ]

    10.3 (a)  BIOGEN shall pay the following amounts within [  *  ]
of the occurrence of the following milestone events with respect to the first 
PRODUCT to reach such milestone:

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    Milestone                                         Amount
    ---------                                         ------

    (i)    [  *  ]                                    [  *  ]

    (ii)   [  *  ]                                    [  *  ]

    (iii)  [  *  ]                                    [  *  ]

    (iv)   [  *  ]                                    [  *  ]

    (v)    [  *  ]                                    [  *  ]

    (vi)   [  *  ]                                    [  *  ]

    (vii)  [  *  ]                                    [  *  ]

    (viii) [  *  ]                                    [  *  ]

    (ix)   [  *  ]                                    [  *  ]

    (x)    [  *  ]                                    [  *  ]

*   Provided that BIOGEN has not given notice of termination of this 
Agreement prior to expiration of such [  *  ] period.  

**  [  *  ] shall be determined by Biogen's decision to commence [  *  ] with 
respect to such chemical entity. Biogen has pre-paid this milestone in 
anticipation of the successful completion of a [  *  ] study with CVT-124, 
pursuant to Section 10.1(e) hereof.

         (b)  In the event BIOGEN does not [  *  ] and this 

--------------------------
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                                       25.

<PAGE>

Agreement has not been terminated,  and (i) [  *  ] planning or ongoing and 
(ii) no material health or safety issue has arisen with respect to the 
clinical use of PRODUCT, BIOGEN will pay CVT the related milestone fee as set 
forth in Section 10.3(a)(iii) above as if it had reached such milestone at 
such time, but such milestone payment shall not be due thereafter when a 
[  *  ] is actually commenced.  In the event that any material health or 
safety issue arises with respect to PRODUCT, BIOGEN shall nevertheless 
continue to use commercially reasonable efforts to develop a PRODUCT.  

         (c)  In the event BIOGEN has not [  *  ] of the notice of decision 
by BIOGEN to commence [  *  ] of a PRODUCT in the United States, and this 
Agreement has not been terminated, BIOGEN will nevertheless pay CVT the 
related milestone set forth in Section 10.3(a)(vii) above in advance as if it 
had reached such milestone at such time, but such milestone shall not be due 
thereafter when such [  *  ]

    10.4 BIOGEN shall keep, and shall cause each of its AFFILIATES to keep, 
full and accurate books of account containing all particulars relevant to its 
sales of PRODUCTS that may be necessary for the purpose of calculating all 
compensation payable to CVT hereunder.  Such books of account shall be kept 
at their principal place of business and for the three (3) years next 
following the end of the calendar year to which each shall pertain, be open 
for inspection by an independent certified public accountant reasonably 
acceptable to BIOGEN, upon reasonable notice during normal business hours at 
CVT's expense for the sole purpose of verifying compensation due under this 
Agreement.  In the event the inspection determines that compensation due CVT 
for any period has been underpaid by [  *  ] or more, then BIOGEN shall pay 
for all costs of the inspection, otherwise the costs of the inspection shall 
be borne by CVT.  In all cases, BIOGEN shall pay to CVT any underpaid 
compensation promptly and CVT shall promptly pay to BIOGEN any overpaid 
compensation.  All information and data reviewed in the inspection shall be 
used only for the purpose of verifying compensation due and shall be treated 
as BIOGEN Confidential Information subject to the obligations of this 
Agreement.  No audit by an agent of CVT shall occur more frequently than once 
during any twelve (12) month period.

    10.5 In each year the amount of compensation due shall be calculated 
quarterly as of the end of each CALENDAR QUARTER and shall be paid quarterly 
within the [  *  ] days next following such date, unless such CALENDAR 
QUARTER is the last CALENDAR QUARTER of the year, in which case the 
compensation due shall be paid within [  *  ] days next following such date.  
Every such payment shall be supported by the accounting prescribed in Section 
10.6 and shall be made in United States currency.  Whenever for the purpose 
of calculating compensation, conversion 

--------------------------
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                                       26.

<PAGE>

from any foreign currency shall be required, such conversion shall be at the 
rate of exchange published in The Wall Street Journal for the last business 
day of the CALENDAR QUARTER.

    10.6 With each quarterly payment, BIOGEN shall deliver to CVT a full and
accurate accounting to include at least the following information:

         (a)  Total billings for PRODUCT subject to Royalty;

         (b)  Deductions applicable as provided in Section 1.17;

         (c)  Applicable royalty rates (including any credits as provided in
Section 10.2(b) or (d));

         (d)  SUBLICENSEE income and royalties thereon; and

         (e)  Total compensation payable to CVT.

    10.7 If the transfer of or the conversion into United States Dollars of 
any remittance due hereunder is not lawful or possible in any country, such 
remittance shall be made by the deposit thereof in the currency of the 
country to the credit and account of CVT or its nominee in any commercial 
bank or trust company located in that country, prompt notice of which shall 
be given to CVT. CVT shall be advised in writing in advance by BIOGEN and 
provide to BIOGEN a nominee, if so desired.

    10.8 Any tax required to be withheld by BIOGEN under the laws of any 
foreign country for the account of CVT, shall be promptly paid by BIOGEN for 
and on behalf of CVT to the appropriate governmental authority, and BIOGEN 
shall use its best efforts to furnish CVT with proof of payment of such tax.  
Any such tax actually paid on CVT's behalf shall be deducted from royalty 
payments due CVT.

    10.9 Compensation shall be due and payable for the manufacture, use and 
sale of an individual PRODUCT only once with respect to the same unit of 
PRODUCT irrespective of the number of patents or claims thereof which cover 
the manufacture, use and sale of such PRODUCT.  In no event shall 
compensation shall be due and payable hereunder for the manufacture, use or 
sale of an individual PRODUCT for which CVT receives compensation in the way 
of royalties under the BML AGREEMENT.

SECTION 11.   REPRESENTATIONS AND WARRANTIES.

    11.1 Each party represents and warrants to the other party that: (i) it 
is free to enter into this Agreement; (ii) in so doing, it will not violate 
any other agreement to which it is a party; and (iii) it has taken all 
corporate action necessary to authorize the 

                                       27.

<PAGE>

execution and delivery of this Agreement and the performance of its 
obligations under this Agreement.

    11.2 (a)  Each party represents that it is not aware of any action, suit, 
inquiry or investigation or any claim, demand or notice of default which if 
adversely determined would affect the rights granted under this Agreement.

         (b)  Each party acknowledges that in entering into this Agreement 
the other party has relied upon information supplied by the disclosing party, 
including, in the case of information supplied by CVT, data and information 
concerning CVT-124 and preclinical and clinical studies and information 
related to CVT PATENT RIGHTS.  Neither party is aware of any data or 
information given to the other party which is untrue or inaccurate or of any 
other data or information which is necessary to make the data and information 
provided to the other party complete and not misleading.  To the best of 
CVT's knowledge, [  *  ]

    11.3 CVT hereby represents, warrants and covenants to BIOGEN that:

         (a)  It is the [  *  ] under this Agreement and has the right and 
has taken all necessary action to [  *  ] provided that the foregoing shall 
not be interpreted as a warranty of non-infringement;

         (b)  To the best of CVT's knowledge, CVT has disclosed to BIOGEN all 
facts that CVT reasonably believes to be [  *  ] known to CVT as of the 
EFFECTIVE DATE;

         (c)  All patent applications included in CVT PATENT RIGHTS existing 
as of the Effective Date are pending and have not been abandoned;

         (d)  CVT [  *  ] to BIOGEN pursuant to this Agreement.

         (e)  CVT will not take any action that would in any way prevent CVT 
from granting the rights granted to BIOGEN under this Agreement with respect 
to CVT PATENT RIGHTS or CVT TECHNOLOGY acquired after the EFFECTIVE DATE or 
which would otherwise [  *  ] BIOGEN under this Agreement.  Nothing herein 
shall prohibit the amendment or modification of the scope of claims during 
the patent prosecution process.

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                                       28.

<PAGE>

         (f)  CVT has [  *  ]

         (g)  CVT will take all actions required by it to maintain its rights 
under the UFRFI LICENSE as in effect on the EFFECTIVE DATE, and shall 
immediately send to BIOGEN any notice of default or breach received by CVT 
under the UFRFI LICENSE.

         (h)  All employees of CVT who perform research and development for 
CVT in connection with CVT's obligations under this Agreement are required to 
assign their rights in any intellectual property arising from such work to 
CVT.  

         (i)  Appendix A contains a complete and accurate list of all CVT 
PATENT RIGHTS in existence as of the EFFECTIVE DATE.

         (j)  CVT will not enforce any patent rights owned or controlled by 
it to prevent the manufacture, use or sale of any PRODUCT for which BIOGEN 
has a royalty obligation to CVT hereunder subject to the license granted 
herein by BIOGEN or its AFFILIATES or SUBLICENSEES, or any person or entity 
purchasing a PRODUCT from any of them.

    11.4 CVT represents that it has not as of the EFFECTIVE DATE [  *  ] the 
manufacture, use or sale of PRODUCT and it is not aware of any infringement 
by a THIRD PARTY of the CVT PATENT RIGHTS.

SECTION 12.   INDEMNIFICATION.

    12.1 INDEMNIFICATION BY BIOGEN.  BIOGEN will defend, indemnify and hold 
harmless CVT, its AFFILIATES  and their employees, agents, officers, 
shareholders and directors and each of them (the "CVT Indemnified Parties") 
from and against any and all third party claims, causes of action and costs 
(including reasonable attorney's fees) of any nature made or lawsuits or 
other proceedings filed or otherwise instituted against the CVT Indemnified 
Parties resulting from or arising out of the manufacture, use or sale of any 
PRODUCT by BIOGEN, its AFFILIATES or SUBLICENSEES, other than those claims 
which result or arise from breach of this Agreement by CVT or failure by CVT 
to comply in any material respect with applicable laws or regulations or the 
negligence or willful misconduct of CVT or any its AFFILIATES or any of their 
employees, agents, officers,  shareholders or directors.

--------------------------
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                                       29.

<PAGE>

    12.2 INDEMNIFICATION BY CVT.  CVT will defend, indemnify and hold 
harmless BIOGEN, its AFFILIATES and their employees, agents, officers, 
shareholders and directors and each of them (the "BIOGEN Indemnified 
Parties") from and against any and all third party claims, causes of action 
and costs (including reasonable attorney's fees) of any nature made or 
lawsuits or other proceedings filed or otherwise instituted against any of 
the BIOGEN Indemnified Parties resulting from or arising out of breach of 
this Agreement by CVT or failure of CVT to comply in any material respect 
with applicable laws or regulations or the negligence or willful misconduct 
of CVT or its AFFILIATES or any of their employees, agents, officers, 
shareholders or directors. 

    12.3 CONDITIONS TO INDEMNIFICATION.  A person or entity that intends to 
claim indemnification under this Section (the "Indemnitee") shall promptly 
notify the indemnifying party (the "Indemnitor") of any loss, claim, damage, 
liability or action in respect of which the Indemnitee intends to claim such 
indemnification, and the Indemnitor shall assume the defense thereof with 
counsel mutually satisfactory to the Indemnitee whether or not such claim is 
rightfully brought; provided, however, that an Indemnitee shall have the 
right to retain its own counsel, with the fees and expenses to be paid by the 
Indemnitor if Indemnitor does not assume the defense, or if representation of 
such Indemnitee by the counsel retained by the Indemnitor would be 
inappropriate due to actual or potential differing interests between such 
Indemnitee and any other person represented by such counsel in such 
proceedings.  The indemnity agreement in this Section shall not apply to 
amounts paid in settlement of any loss, claim, damage, liability or action if 
such settlement is effected without the consent of the Indemnitor, which 
consent shall not be withheld or delayed unreasonably.  The failure to 
deliver notice to the Indemnitor within a reasonable time after the 
commencement of any such action, only if prejudicial to its ability to defend 
such action, shall relieve such Indemnitor of any liability to the Indemnitee 
under this Section, but the omission so to deliver notice to the Indemnitor 
will not relieve it of any liability that it may have to any Indemnitee 
otherwise than under this Section.  The Indemnitee under this Section, its 
employees and agents, shall cooperate fully with the Indemnitor and its legal 
representatives in the investigations of any action, claim or liability 
covered by this indemnification.

SECTION 13.   ASSIGNMENT; SUCCESSORS.

    13.1 This Agreement shall not be assignable by either of the parties 
without the prior written consent of the other party (which consent shall not 
be unreasonably withheld), except that BIOGEN without the consent of CVT may 
assign this Agreement or any of its rights and obligations hereunder to an 
AFFILIATE or to an entity with which BIOGEN shall merge or consolidate or to 
which BIOGEN shall sell or assign all or substantially all of its assets, and 
except that CVT without the consent of BIOGEN 

                                       30.

<PAGE>

may assign this Agreement to an entity with which CVT shall merge or 
consolidate or to which CVT shall sell or assign all or substantially all of 
its assets.

    13.2 Subject to the limitations on assignment herein, this Agreement 
shall be binding upon and inure to the benefit of said successors in interest 
and assigns of CVT and BIOGEN. 

SECTION 14.   TERMINATION.

    14.1 Except as otherwise specifically provided herein and unless sooner 
terminated pursuant to Sections 14.2, 14.3, 14.4 or 14.9 of this Agreement, 
this Agreement and the licenses and rights granted hereunder shall remain in 
full force and effect until BIOGEN's obligations to pay compensation 
hereunder terminate.  Upon expiration of BIOGEN's obligation to pay 
compensation hereunder with respect to a specific country and specific 
PRODUCT as to which BIOGEN's license is then in effect, the license granted 
to BIOGEN with respect to such country and such PRODUCT pursuant to Section 
2.1 shall be deemed to be fully paid and BIOGEN shall thereafter have a 
royalty-free right to use the CVT PATENT RIGHTS and CVT TECHNOLOGY and to 
make, use, import and sell such PRODUCT in such country.

    14.2 Upon breach of any material provisions of this Agreement by either 
party to this Agreement, in the event the breach is not cured within [  *  ] 
days after written notice to the breaching party by the other party, in 
addition to any other remedy it may have, the other party at its sole option 
may terminate this Agreement, provided that such other party is not then in 
breach of this Agreement.

    14.3 Either party to this Agreement may, upon giving notice of 
termination, immediately terminate this Agreement upon receipt of notice that 
the other party has become insolvent or has suspended business in all 
material respects hereof, or has consented to an involuntary petition 
purporting to be pursuant to any reorganization or insolvency law of any 
jurisdiction, or has made an assignment for the benefit of creditors or has 
applied for or consented to the appointment of a receiver or trustee for a 
substantial part of its property; provided, however, that the insolvency or 
bankruptcy of CVT shall not operate to terminate the licenses granted to 
BIOGEN hereunder unless BIOGEN elects to terminate the Agreement as provided 
herein, and BIOGEN may elect to retain its licenses as provided in 11 U.S.C. 
Section 356.

    14.4 In addition to the foregoing, within [  *  ] days of BIOGEN's 
receipt of the data from the [  *  ] BIOGEN may terminate this Agreement upon 
written notice in its sole discretion.  At any time after [  *  ] BIOGEN may 
terminate this Agreement for any reason upon [  *  ] days prior written 
notice to CVT.  

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                                       31.

<PAGE>

    14.5 Upon any termination of this Agreement, all licenses and rights 
granted to BIOGEN shall terminate forthwith, except that BIOGEN shall be 
entitled to, but shall not be obligated [  *  ] covered by this Agreement 
which exists as of the date of the termination, so long as BIOGEN [  *  ] in 
accordance with the same terms and conditions as set forth in this Agreement.

    14.6 The obligations of Sections 6 and 12, as well as Sections 14.5, 
14.6, 14.7, 14.8,  15.4, and 15.8 and the repayment obligation under the 
Note(s) shall survive any termination of this Agreement.

    14.7 In the event of any termination under Section 14.4 or 14.9 or in the 
event CVT terminates this Agreement pursuant to Sections 14.2 or 14.3, BIOGEN 
shall grant to CVT a non-exclusive, worldwide, royalty-bearing license under 
[  *  ] and [  *  ] solely to make, have made, import, use and sell PRODUCTS 
and shall make available to CVT  copies of all documents containing or 
comprising such [  *  ] and [  *  ] CVT shall [  *  ] BIOGEN in making such 
[  *  ] and [  *  ] available to CVT. Furthermore, in the event that, at the 
time of termination under Section 14.4 or 14.9 or of termination by CVT 
pursuant to Sections 14.2 or 14.3, [  *  ] funding for such [  *  ] unless 
[  *  ] Upon such termination the [  *  ] shall, to the extent permissible by 
law, be [  *  ] To this end, BIOGEN agrees that upon such termination it 
shall [  *  ] relating to CVT-124 and for [  *  ] by CVT hereunder.  BIOGEN 
shall promptly deliver copies of such filings to CVT and execute any and all 
documents and instruments reasonably requested by CVT to confirm the 
assignment of such filings.  CVT and BIOGEN shall cooperate in the transition 
of BIOGEN's regulatory filings to CVT in such a way as not to harm either 
CVT's or BIOGEN's relationship with the relevant regulatory authorities.  To 
that end, CVT may elect to have one or more of BIOGEN's employees participate 
in meetings between CVT and regulatory authorities regarding assignment of 
BIOGEN's regulatory filings.  

    14.8 In the event that, following any termination of this Agreement, CVT, 
or its permitted successor or assignee, subsequently commercializes a PRODUCT 
by itself or in conjunction with a THIRD PARTY, CVT, or its permitted 
successor or assignee, 

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                                       32.

<PAGE>

shall pay a royalty to BIOGEN on sales of PRODUCT in the TERRITORY in 
accordance with the following:

         (a)  If the Agreement has been terminated prior to receipt by CVT of 
the [  *  ] milestone payable in accordance with Section 10.3(a)(i) hereof 
[  *  ] and the manufacture, use or sale of the commercialized PRODUCT is 
covered by a VALID CLAIM of the BIOGEN CVT-124 PATENTS or includes any of the 
BIOGEN CVT-124 TECHNOLOGY, CVT shall pay BIOGEN royalties on net sales of 
PRODUCT and a percentage of CVT'S SUBLICENSE INCOME as follows:

              (i)  Royalties payable to BIOGEN shall be [  *  ] and 
determined based on worldwide annual net sales (calculated in accordance with 
the NET SALES definition set forth in Section 1.17 hereof, and including NET 
SALES under the BML AGREEMENT) in each calendar year in accordance with the 
following table:

      [  *  ] Annual Net Sales             Royalty
    -----------------------------------------------
    Up to [  *  ] Million                  [  *  ]

    [  *  ] Million to [  *  ] Million     [  *  ]

    Over [  *  ] Million                   [  *  ]

              (ii) CVT shall pay to BIOGEN [  *  ] of SUBLICENSE INCOME 
received by it from sublicensees.  Prior to calculation of Biogen's [  *  ] 
CVT may deduct from SUBLICENSE INCOME any royalty paid by CVT to [  *  ] on 
account of sales of PRODUCT in the TERRITORY in such period.

         (b)  If the Agreement has been terminated after receipt by CVT of 
the [  *  ] but prior to completion of a [  *  ] of the PRODUCT, CVT shall 
pay BIOGEN royalties on net sales of PRODUCT and a percentage of SUBLICENSE 
INCOME as follows:

              (i)  Royalties payable to BIOGEN shall be [  *  ] and 
determined based on worldwide annual net sales (calculated in accordance with 
the NET SALES definition set forth in Section 1.17 hereof, and including NET 
SALES under the BML AGREEMENT) in each calendar year in accordance with the 
following table:

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                                       33.

<PAGE>

    [  *  ] Annual Net Sales               Royalty
    -----------------------------------------------
    Up to [  *  ] Million                  [  *  ]

    [  *  ] Million to [  *  ] Million     [  *  ]

    Over [  *  ] Million                   [  *  ]

              (ii) CVT shall pay to BIOGEN [  *  ] of SUBLICENSE INCOME 
received by it from sublicensees.  Prior to calculation of Biogen's [  *  ] 
share, CVT may deduct from SUBLICENSE INCOME any royalty paid by CVT to 
[  *  ] on account of sales of PRODUCT in the TERRITORY in such period.

         (c)  If the Agreement has been terminated after completion of a 
[  *  ] of the PRODUCT, but prior to the availability of [  *  ] CVT shall 
pay BIOGEN royalties on net sales of PRODUCT and a percentage of SUBLICENSE 
INCOME as follows:

              (i)  Royalties payable to BIOGEN shall be [  *  ] and 
determined based on worldwide annual net sales (calculated in accordance with 
the NET SALES definition set forth in Section 1.17 hereof, and including NET 
SALES under the BML AGREEMENT) in each calendar year in accordance with the 
following table:

    [  *  ] Annual Net Sales                Royalty
    -----------------------------------------------
    Up to [  *  ] Million                   [  *  ]

    [  *  ] Million to [  *  ] Million      [  *  ]

    Over [  *  ] Million                    [  *  ]

              (ii) CVT shall pay to BIOGEN [  *  ] of SUBLICENSE INCOME 
received by it from sublicensees.  Prior to calculation of Biogen's [  *  ] 
share, CVT may deduct from SUBLICENSE INCOME any royalty paid by CVT to 
[  *  ] on account of sales of PRODUCT in the TERRITORY in such period.

         (d)  If the Agreement has been terminated after the availability of 
[  *  ] of the PRODUCT, CVT shall pay BIOGEN royalties on net sales of 
PRODUCT and a percentage of SUBLICENSE INCOME as follows:
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                                       34.

<PAGE>

              (i)  Royalties payable to BIOGEN shall be [  *  ] and 
determined based on worldwide annual net sales (calculated in accordance with 
the NET SALES definition set forth in Section 1.17 hereof, and including NET 
SALES under the BML AGREEMENT) in each calendar year in accordance with the 
following table:

    [  *  ] Annual Net Sales               Royalty
    -----------------------------------------------
    Up to [  *  ] Million                  [  *  ]

    [  *  ] Million to [  *  ] Million     [  *  ]

    Over [  *  ] Million                   [  *  ]

              (ii) CVT shall pay to BIOGEN [  *  ] of SUBLICENSE INCOME 
received by it from sublicensees.  Prior to calculation of Biogen's [  *  ] 
share, CVT may deduct from SUBLICENSE INCOME any royalty paid by CVT to 
[  *  ] on account of sales of PRODUCT in the TERRITORY in such period.

         (e)  In the event that after the EFFECTIVE DATE CVT becomes 
obligated to pay any royalties or other sums to THIRD PARTIES because the 
manufacture, use or sale of PRODUCTS in the TERRITORY infringes the 
intellectual property rights of such THIRD PARTIES, CVT shall be entitled to 
credit [  *  ] of any such obligations against Royalties due to BIOGEN 
pursuant to this Section 14.8; provided, however, that in no event shall such 
credit reduce Royalties payable to BIOGEN hereunder for any CALENDAR QUARTER 
by more than [  *  ] of the amounts otherwise due.  [  *  ]

         (f)  CVT shall keep full and accurate books of account containing 
all particulars relevant to its sales of PRODUCTS that may be necessary for 
the purpose of calculating all compensation payable to BIOGEN hereunder, and 
shall be subject to the same provisions as are contained in Section 10.4 
hereof.

         (g)  All payments due to BIOGEN pursuant to this Section 14.8 shall 
be made in accordance with Sections 10.5, 10.6 (excluding the section 
references therein), 10.7 and 10.8 hereof, in each case substituting CVT for 
BIOGEN as appropriate, and vice versa.

    14.9 This Agreement shall automatically terminate upon the termination of 
the BML AGREEMENT.

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                                       35.

<PAGE>

SECTION 15.   GENERAL PROVISIONS.

    15.1 Neither party shall be liable to the other party for damages or loss 
occasioned by failure of performance by the defaulting party if the failure 
is occasioned by war, fire, explosion, flood, strike or lockout, embargo, or 
any similar cause beyond the control of the defaulting party, provided that 
the party claiming this exception has exerted all reasonable efforts to avoid 
or remedy such event and provided such event does not extend for more than 
six (6) months. 

    15.2 The relationship between CVT and BIOGEN is that of independent 
contractors.  CVT and BIOGEN are not joint venturers, partners, principal and 
agent, master and servant, employer or employee, and have no relationship 
other than as independent contracting parties.  CVT shall have no power to 
bind or obligate BIOGEN in any manner.  Likewise, BIOGEN shall have no power 
to bind or obligate CVT in any manner.

    15.3 This Agreement and the BML AGREEMENT set forth the entire agreement 
and understanding between the parties as to the subject matter hereof and 
supersede all prior agreements in this respect.  There shall be no amendments 
or modifications to these Agreements, except by a written document which is 
signed by both parties.

    15.4 This Agreement shall be construed and enforced in accordance with 
the laws of the State of Delaware, U.S.A. without reference to its 
choice-of-law principles.

    15.5 The headings in this Agreement have been inserted for the 
convenience of reference only and are not intended to limit or expand on the 
meaning of the language contained in the particular or section or paragraph.

    15.6 Any delay in enforcing a party's rights under this Agreement or any 
waiver as to a particular default or other matter shall not constitute a 
waiver of a party's right to the future enforcement of its rights under this 
Agreement, excepting only as to an expressed written and signed waiver as to 
a particular matter for a particular period of time.

    15.7 In conducting any activities under this Agreement or in connection 
with the manufacture use or sale of PRODUCT, BIOGEN shall comply with all 
applicable laws and regulations including, but not limited to, all Export 
Administration Regulations of the United States Department of Commerce.

    15.8 NOTICES.  Any notices given pursuant to this Agreement shall be in 
writing and shall be deemed delivered upon the earlier of (i) when received 
at the address set forth below, or (ii) three (3) business days after mailed 
by certified or registered mail 

                                       36.

<PAGE>

postage prepaid and properly addressed, with return receipt requested, or 
(iii) when sent, if sent, by facsimile, as confirmed by certified or 
registered mail.  Notices shall be delivered to the respective parties as 
indicated:

    If to CVT:                    CV Therapeutics, Inc.
                                  3172 Porter Drive
                                  Palo Alto, CA 94304
                                  Attn: CEO


              with a copy to:     Cooley Godward LLP
                                  3000 El Camino Real
                                  Palo Alto, CA 94306
                                  Attn: Robert L. Jones, Esq.
                                  Deborah Marshall, Esq.


    If to BIOGEN:                 Biogen, Inc.
                                  14 Cambridge Center
                                  Cambridge, MA 02142
                                  Attn: President

              with a copy to      Vice President - General Counsel

    15.9 This Agreement may be executed in any number of separate 
counterparts, each of which shall be deemed to be an original, but which 
together shall constitute one and the same instrument.

    IN WITNESS WHEREOF, the parties have executed this Agreement as of the 
date set forth above.

CV THERAPEUTICS, INC.                  BIOGEN, INC.

By: /s/ Louis Lange                    By: /s/ James R. Tobin
   --------------------------------       --------------------------------

Name: Louis Lange                      Name: James R. Tobin
     ------------------------------         ------------------------------

Title: CEO                             Title: President and CEO
      -----------------------------          -----------------------------


                                       37.

<PAGE>

                                      APPENDIX A

                                    PATENT RIGHTS

                                    [SEE ATTACHED]


<PAGE>

                                     U. S. PATENTS
<TABLE>
<CAPTION>

              Docket No./                                                                   Issue Date/   Patent
Patent No.    Serial No.     Title                                     Inventor(s)          Date File     Expires
--------------------------------------------------------------------------------------------------------------------
<S>           <C>            <C>                                       <C>                  <C>           <C>

[                                                            *                                                      ]

</TABLE>

  [  *  ]


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<PAGE>

                      U.S. PENDING PATENT APPLICATIONS

<TABLE>
<CAPTION>

Docket No./
Serial No.    Descriptive Title                         Inventor(s)            Date Filed     Status
------------------------------------------------------------------------------------------------------------
<S>           <C>                                       <C>                    <C>            <C>

[                                                            *                                                      ]

</TABLE>

[  *  ]

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                                       2

<PAGE>

                      U.S. PENDING PATENT APPLICATIONS (CONT'D)


<TABLE>
<CAPTION>

Docket No./
Serial No.    Descriptive Title                         Inventor(s)            Date Filed     Status
----------------------------------------------------------------------------------------------------------------
<S>           <C>                                       <C>                    <C>            <C>

[                                                             *                                                 ]

</TABLE>

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[  *  ]

                                       3
<PAGE>

                    U.S. PENDING PATENT APPLICATIONS (CONT'D)


<TABLE>
<CAPTION>

Docket No./
Serial No.    Descriptive Title                         Inventor(s)            Date Filed     Status
-------------------------------------------------------------------------------------------------------------
<S>           <C>                                       <C>                    <C>            <C>

[                                                             *                                                 ]

</TABLE>

[  *  ]

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                                       4

<PAGE>


                      U.S. PENDING PATENT APPLICATIONS (CONT'D)


<TABLE>
<CAPTION>

Docket No./
Serial No.    Descriptive Title                         Inventor(s)            Date Filed     Status
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<S>           <C>                                       <C>                    <C>            <C>

[                                                             *                                                 ]

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[  *  ]

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                             FOREIGN PATENT APPLICATIONS 


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Docket No./
Serial No.           Descriptive Title                              Inventor(s)            Date Filed     Status
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<S>                  <C>                                            <C>                    <C>            <C>

[                                                             *                                                 ]




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                         FOREIGN PATENT APPLICATIONS (CONT'D)


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Docket No./
Serial No.           Descriptive Title                              Inventor(s)            Date Filed     Status
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<S>                  <C>                                            <C>                    <C>            <C>

[                                                             *                                                 ]

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<PAGE>

                                   APPENDIX B

                              CLINICAL TRANSITION
                                           

    This Appendix shall govern the transition of the conduct of clinical trials
for CVT-124 from CVT to BIOGEN.    In the event of any inconsistencies between
this Appendix and the provisions of the Agreement, the provisions of this
Appendix shall govern.

    A.   [  *  ]  In the interest of avoiding any 
delay in the commencement of such study, BIOGEN and CVT agree as follows:

    CVT has entered into contracts with [  *  ] and a [  *  ] prior to the 
EFFECTIVE DATE for the conduct of CVT2123, true and correct copies of which 
have been provided to BIOGEN.  CVT is in the process of negotiating the 
remaining contracts necessary for the conduct of CVT2123, but shall not enter 
into any such contracts without the prior approval of BIOGEN.  Promptly after 
the EFFECTIVE DATE, BIOGEN and CVT shall enter into a contract pursuant to 
which CVT agrees INTER ALIA to manage the study pursuant to the direction of, 
and for the sole and exclusive benefit of, BIOGEN and agrees to assign 
exclusively to BIOGEN all rights and data from the study, and BIOGEN agrees 
to reimburse CVT for [  *  ] Such amounts shall be paid net thirty (30) days 
on CVT's invoices submitted at the end of each quarter.  Said agreement shall 
also provide for [  *  ] as is necessary to comply with applicable law for so 
long as [  *  ] In no event shall [  *  ]

    Notwithstanding the provisions of Section 4.1 of the Agreement, CVT shall 
directly supply all materials needs for CVT2123.  Delivery of any inventory 
of CVT-124 not needed for CVT2123 shall be made to BIOGEN in accordance with 
Section 4.1.

    B.   ALL OTHER CLINICAL STUDIES.  Notwithstanding Section 4.3 of the 
Agreement, CVT shall not enter into any contracts, or make any commitments to 
any THIRD PARTIES, with respect to any other clinical studies.  In the event 
that CVT does enter into any such contracts, or make any such commitments, 
BIOGEN shall not be bound by such contracts or commitments, and all 
responsibility therefor shall remain with CVT.

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The provisions of the second sentence of Section 4.3 of the Agreement are 
solely for the benefit of BIOGEN and shall not confer upon CVT any rights 
with respect the design, conduct or results of any clinical studies.


<PAGE>

                                      APPENDIX C

                                  CVT-124 INVENTORY

                                    [See attached]

<PAGE>

                                  CVT-124 INVENTORY

---------------------------------------------------------------------
PRODUCT                                   CURRENT STOCK
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[                               *                             ]

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<PAGE>

                                      APPENDIX D

                                    PRESS RELEASE

                                    [See attached]


<PAGE>


CONTACT

Kathy Stafford
Chief Financial Officer
CV Therapeutics
415-812-9507

Biogen Media Contact:
Kathryn R. Bloom
Director of Communications
Biogen, Inc.
617-679-2851

Biogen Investment Community Contact:
Richard E.N. Lundberg
Manager, Investor Relations
Biogen, Inc.6179-679-2822

             BIOGEN AND CV THERAPEUTICS ANNOUNCE COLLABORATION ON CVT-124
                             FOR CONGESTIVE HEART FAILURE

CAMBRIDGE, MA (March 10, 1997) -- Biogen, Inc. (NASDAQ/BGEN) and CV 
Therapeutics (NASDAQ/CVTX) today announced that they have signed an agreement 
to collaborate on the development of CVT-124, a novel therapeutic for the 
treatment of edema associated with Congestive Heart Failure (CHF) that is 
expected to enter a multi-center Phase II clinical trial within the next 
month.

Under the terms of the agreement, Biogen and its wholly owned subsidiary, 
Biotech Manufacturing Limited, will receive exclusive worldwide rights to 
develop and sell CVT-124.  Biogen and CV Therapeutics will participate in 
developing the drug, but Biogen will pay all costs of commercializing the 
product.  CV Therapeutics will receive from Biogen upfront payments totaling 
$16 million, including a $5 million upfront cash payment, a $7 million equity 
investment of CV Therapeutics stock at $10.45 per share, advance funding of a 
development milestone and partial access to a line of credit.  In addition, 
Biogen will pay CV Therapeutics significant milestone payments and royalties 
on clinical progress and product sales.  Further details of the agreement 
were not announced.

Congestive Heart Failure is a chronic, progressive disease that affects 
approximately four-to-five million people in the United States.  Its 
prevalence is increasing at 10 percent per year, primarily


<PAGE>

due to the aging population as well as improved survival in heart disease 
patients.  Patients with CHF experience both a chronic course of the disease, 
as well as acute episodes that, in many cases,  require hospitalization.  
Edema, or fluid retention in the lungs and extremities, is a significant 
symptom of the disease, leading to increased morbidity and need for 
hospitalization.  In its most severe form, CHF results in a 50 percent 
one-year mortality rate.

CVT-124, a highly selective adenosine A(1)-receptor antagonist, could 
represent a novel therapy for the treatment of edema associated with CHF.  
Proof of this new mechanism of action has been demonstrated both in animal 
models and in a clinical Phase I study completed in 1996.  This new approach 
could be a significant advance because current therapies can lead to clinical 
resistance and unwanted side effects, such as potassium loss and impairment 
of kidney function.  Because of some of its potential properties, CVT-124 may 
be particularly useful in CHF patients who are resistant to current therapies 
and/or have renal impairment.

Jim Tobin, Biogen's President and Chief Executive Officer, said, "Developing 
Biogen's pipeline is a major strategic imperative for the Company, and we are 
pleased to be collaborating with CV Therapeutics to help meet this objective. 
CVT-124 represents a very promising commercial opportunity to enter an 
underserved market with a late-stage therapeutic.  We believe CVT-124, with 
its novel mechanism of action, may have a major impact in the treatment and 
management of Congestive Heart Failure.  It is a very attractive fit with 
Biogen's strategy of developing therapeutics for large underserved markets, 
such as neurological, cardiovascular and renal diseases."

Lou Lange, Chairman and Chief Executive Officer of CV Therapeutics, said, "In 
Biogen, we believe we have found partner for CVT-124 who can bring the 
product to market quickly and with whom we can work closely on development of 
this promising compound.  Biogen's outstanding performance in commercializing 
AVONEX-TM- gives us confidence that they will maximize the potential of 
CVT-124."

In addition to historical information, this press release contains 
forward-looking statements that involve risks and uncertainties that could 
cause actual results to differ materially from those reflected in such 
forward-looking statements.  Reference is made in particular to 
forward-looking statements regarding the timing of clinical trials, the 
potential results of drug development and the commercial opportunity for 
CVT-124.  Drug development involves a high degree of risk.  There are many 
factors which could cause actual results to differ from the Company's current 
expectations, including the Company's ability to demonstrate that CVT-124 is 
safe and effective at each stage of the clinical trial process; to meet 
applicable regulatory standards and receive required regulatory approval; to 
obtain and maintain necessary patents and licenses; to be capable of 
producing the product in commercial quantities at reasonable costs and to 
compete successfully against other products.

Biogen, Inc., headquartered in Cambridge, MA, is a biopharmaceutical company 
principally engaged in discovering and developing drugs for human healthcare 
through genetic engineering.  The Company's revenues are generated from U.S. 
sales of AVONEX-TM- (Interferon beta-1a) for treatment of relapsing forms of 
multiple sclerosis and from the worldwide sales by licenses of a 

<PAGE>

number of products, including alpha interferon and hepatitis B vaccines and 
diagnostic products.  Biogen is focused primarily on developing and testing 
novel products for multiple sclerosis, inflammatory, respiratory and kidney 
diseases and certain viruses and cancers.  For copies of press releases and 
additional information about the Company, please consult Biogen's Homepage on 
the World Wide Web at http://www.biogen.com.

CV Therapeutics, headquartered in Palo Alto, CA, is a biopharmaceutical 
company focused exclusively on the application of molecular cardiology to the 
discovery, development and commercialization of novel, small molecule drugs 
for the treatment of cardiovascular diseases.

                                     #    #    #


030796
s.97draft.cvt


<PAGE>

                                      APPENDIX E

                               RESEARCH PLAN - PHASE 1

                                    [SEE ATTACHED]


<PAGE>

                                   RESEARCH PROGRAM

OBJECTIVE
[  *  ]

STRUCTURE OF COLLABORATION
[  *  ]

PROGRAM PRIORITIES
[  *  ]

APPROACH
[  *  ]

RESOURCE ALLOCATION AT [  *  ] PER FULL TIME EQUIVALENT (FTE)
[  *  ]


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<PAGE>

                            [LOGO] THERAPEUTICS
                                    RESEARCH

<TABLE>

<S>                             <C>                                  <C>
[                                        *                                    ]
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<PAGE>

                                      APPENDIX F

                                ARBITRATION PROCEDURE

In the event of a disagreement between the parties under Section 10.2(e) of 
the Agreement, which disagreement cannot be amicably resolved by the good 
faith efforts of the parties pursuant to such Section 10.2(e), then such 
dispute shall be resolved by binding Alternative Dispute Resolution ("ADR") 
in the manner described below:

    (a)  If a party intends to begin the ADR to resolve the disagreement, 
such party shall provide written notice to the other party informing the 
other party of such intention.  Within 5 business days following the receipt 
of the original ADR notice ("Notice Date") a neutral shall be selected by the 
then President of the American Arbitration Association ("AAA") or by such 
other individual as the parties may agree in good faith.  The neutral 
selected shall have experience in the biotechnology and/or pharmaceutical 
industry and shall not be an employee, director or shareholder of either a 
party or of an AFFILIATE of either party.

    Each party shall have ten (10) business days from the date the neutral is 
selected to object in good faith to the selection of that person.  If either 
party makes such an objection, the then President of  AAA shall as soon as 
possible thereafter, elect another neutral under the same conditions set 
forth above.  This second selection shall be final.

    (b)  No later than (90) business days after selection, the neutral shall 
hold a hearing to resolve the issue.

         (i)  Each party shall have the right to be represented by counsel at 
    the hearing.

         (ii) The hearing shall be held at such place as agreed upon by the   
  parties or if they are unable to agree at a place designated by the     
neutral.

    (c)  The ADR proceeding shall be confidential and the neutral shall issue 
appropriate protective orders to safeguard each party's Confidential 
Information.  Except as required by law, no party shall make (or instruct the 
neutral to make) any public announcement with respect to the proceedings or 
decision of the neutral without the prior written consent of each other 
party. The existence of the dispute submitted to ADR, and the award of the 
neutral, shall be kept in confidence by the parties and the neutral, except 
as required in connection with the enforcement of such award or as otherwise 
required by applicable law.


<PAGE>


    (d)  It is the intention of the parties that discovery, although 
permitted as described herein, will be extremely limited except in 
exceptional circumstances.  The neutral shall permit such limited discovery 
necessary for an understanding of any legitimate issue raised in the ADR, 
including the production of documents.  Each party shall be permitted but not 
required to take the deposition of not more than five (5) persons, each such 
deposition not to exceed six (6) hours in length.  If the neutral believes 
that exceptional circumstances exist, and additional discovery is necessary 
for a full and fair resolution of the issue, the neutral may order such 
discovery as the neutral deems necessary.  At the hearing the parties may 
present testimony (either by live witness or deposition) and documentary 
evidence.  The neutral shall have sole discretion with regard to the 
admissibility of any evidence and all other matters relating to the conduct 
of the hearing.

    (e)  Each party shall be entitled to no more than four (4) hours of 
hearing to present testimony or documentary evidence, unless such time period 
is extended by mutual agreement between the parties or is otherwise allowed 
by the neutral.  The testimony of both parties shall be presented during the 
same calendar day.  Such time limitation shall include any direct, cross or 
rebuttal testimony, but such time limitation shall include any direct, cross 
or rebuttal testimony, but such time limitation shall only be charged against 
the party conducting such direct, cross or rebuttal testimony.  It shall be 
the responsibility of the neutral to determine whether the parties have had 
the presentation time to which they are entitled.

    (f)  At least fifteen (15) business days prior to the date set for the 
hearing, each party shall submit to each other party and the neutral a list 
of all documents on which such party intends to rely in any oral or written 
presentation to the neutral and a list of all witnesses, if any, such party 
intends to call at such hearing and a brief summary of each witness' 
testimony.

    At least five (5) business days prior to the hearing, each party must 
submit to the neutral and serve on each other party a proposed ruling on the 
issue to be resolved.  Such writing shall be limited to representing the 
proposed ruling, shall contain no argument or analysis of the facts or 
issues, and shall be limited to not more than ten (10) pages, unless such 
writing is extended by mutual agreement between the parties or is otherwise 
allowed by the neutral.

    (g)  Not more than fifteen (15) business days following the close of 
hearings, the parties may each submit post hearing briefs to the neutral 
addressing the evidence and issues to be resolved.  Such post hearing briefs 
shall not be more than fifty (50) pages, unless such writing is extended by 
mutual agreement between the parties or is other wise allowed by the neutral.

<PAGE>

    (h)  The neutral shall rule on the disputed issue after the hearing as 
expeditiously as possible, but in no event more than forty-five (45) days 
after the close of the hearings.  Such ruling shall adopt in its entirety the 
proposed ruling of one of the parties.  The neutral shall, in rendering his 
decision, apply the substantive law of the State of Delaware, without giving 
effect to its principles of conflicts of law, and without giving effect to 
any rules or laws relating to arbitration.

    (i)  Any judgment upon the award rendered by the neutral may be entered 
in any court having jurisdiction thereof.  The decision rendered in any such 
ADR shall be final and not appealable, except in cases of fraud or bad faith 
on the part of the neutral or any party to the ADR proceeding in connection 
with the conduct of such proceedings, and shall be enforceable in any court 
of competent jurisdiction.  No punitive damages shall be recoverable by 
either party in such a proceeding.

    (j)  Each party shall pay its own costs (including, without limitation, 
attorneys fees) and expenses in connection with such ADR.

    (k)  In the event either party contends that there has been fraud or bad 
faith by the other party or in connection with the conduct of any ADR, a 
second ADR shall be held to determine whether there has been fraud or bad 
faith.  If, as a result of the second ADR, it is determined that there has 
been fraud or bad faith, the decision affected by such fraud or bad faith 
shall be vacated and another ADR shall be held to resolve the original 
dispute.