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                                                                   Exhibit 10.83



                       [SEQUANA THERAPEUTICS LETTERHEAD]



                                                                 January 9, 1998

Claus-Jorg Ruetsch
VP of International Legal Affairs
German Offices
Sandhofer Strasse 176
D-68305 Mannheim
Germany


Dear Dr. Ruetsch,

        COLLABORATIVE RESEARCH AGREEMENT BETWEEN SEQUANA THERAPEUTICS, INC., AND
THE CORANGE INTERNATIONAL LTD. EFFECTIVE JUNE 30, 1995 ("AGREEMENT")

We refer to the Agreement and confirm that it is the mutual agreement of the
parties to amend the Agreement effective January 9, 1998 to delete Section
2.2(ii) in its entirety and replace it with the following:

               "Corange or its nominee shall purchase equity securities issued
               by AxyS Pharmaceuticals, Inc. ("AxyS") in the amount of
               $1,250,000 per year on each annual anniversary of the Effective
               Date through February 14, 1999. The securities shall be common
               stock of AxyS purchased by Corange or its nominee at a price per
               share equal to one hundred thirty-five percent (135%) of the
               average closing sale price of AxyS common stock as reported in
               the Wall Street Journal for the twenty (20) day period ending as
               of the date three (3) business days prior to the date of purchase
               of shares for such year."

All other terms of the Agreement remain unchanged.


We are enclosing duplicate copies of this letter. If the above is acceptable to
Corange, please have the copies signed on behalf of Corange by a duly authorized
signatory and return one fully signed copy to us for our records.



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Sincerely,

/s/  Tim Harris

Tim Harris, Ph.D.
Sr. VP of Research & Development


Accepted this 14 day of January, 1998
Corange International Ltd.



Per:    /s/ Gerald Moeller
        ---------------------
Title:  CEO

- -----------------------------
cc:     Sibylle Hubschmann
        Business Development
        Boehringer Mannheim



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