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                                                                    EXHIBIT 10.2


                      FIRST AMENDMENT TO SUBLEASE AGREEMENT

      THIS FIRST AMENDMENT TO SUBLEASE AGREEMENT (this "Amendment") is made as
of September 29, 2003 (the "Effective Date") by and between COULTER
PHARMACEUTICAL, INC., a Delaware corporation ("Sublessor"), and AXYS
PHARMACEUTICALS, INC., a Delaware corporation ("Sublessee").

      A. Sublessor and Sublessee have previously entered into that certain
Sublease Agreement dated as of September 11, 2003 with respect to a portion of
that certain real property commonly known as 630 Gateway Boulevard, South San
Francisco, California (the "Sublease Agreement").

      B. The parties hereto acknowledge that certain references to the Lease and
the document attached as Exhibit A to the Sublease Agreement as the Lease are
incorrect and desire to amend the terms of the Sublease Agreement by this
Amendment to correct such errors.

      C. Capitalized terms used herein and not otherwise defined herein shall
have the meaning given to them in the Sublease Agreement.

      For valuable consideration, the receipt of which is hereby acknowledged,
the parties hereto agree that the Sublease Agreement is hereby amended as
follows:

      1. Section 1 of the Sublease Agreement. The definitions of "Landlord" and
"Lease" contained in Section 1 of the Sublease Agreement are hereby deleted in
their entirety and the following definitions are hereby respectively substituted
in lieu thereof:

                  "LANDLORD means Gateway Boulevard Associates II, LLC, a
                  California limited liability company, and its successors and
                  assigns."

                  "LEASE means that certain Lease Agreement dated May 19, 2000,
                  between HMS Gateway Office, L.P., a Delaware limited
                  partnership, the predecessor-in-interest of Landlord, as
                  landlord, and Sublessor, as tenant; as amended by that certain
                  First Amendment to Lease Agreement dated as of January 15,
                  2002; and that certain Amended and Restated Agreement
                  Concerning Assignment and Sublease Profits dated as of May 23,
                  2002; a copy of the Lease is attached hereto as Exhibit A."

      2. Section 5(b) of the Sublease Agreement. Section 5(b) of the Sublease
Agreement is hereby deleted in its entirely and the following provision is
hereby substituted in lieu thereof:

                  "(b) Relationship Between Sublessee and Sublessor. Except as
                  otherwise provided herein, all of the terms and conditions
                  contained in the Lease are incorporated herein as terms and
                  conditions of this Sublease with each reference therein to
                  "Landlord," "Tenant," the "Lease" and the "Premises," being
                  deemed to refer to Sublessor, Sublessee, this Sublease, and
                  the Premises, respectively), except for the following
                  provisions of the Lease, which are not incorporated into this
                  Sublease: Sections 3, 4(a), 4(d), 7, 8(c), 8(d), 10, 16(b),
                  38, 49, 50, 51 and 52, and Exhibits A, B, C,

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                  D, G, H and I. Notwithstanding anything to the contrary
                  contained herein, with respect to any specific obligation in
                  the Lease required to be performed by Landlord, to the extent
                  Landlord has performed such obligation Sublessor shall not be
                  required to do so."

      2. Exhibit A of the Sublease Agreement. Exhibit A of the Sublease
Agreement is hereby deleted in its entirely and Exhibit A of this Amendment is
hereby substituted in lieu thereof.

      3. Full Force. As amended by this Amendment, the Sublease Agreement
remains in full force and effect and is ratified, confirmed, and approved.

      4. Captions. All captions and headings in this Amendment are for the
purposes of reference and convenience and shall not limit or expand the
provisions of this Amendment.

      5. Counterparts. This Amendment may be executed in one or more
counterparts, each of which shall constitute an original, and all of which shall
constitute a single agreement.



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            IN WITNESS WHEREOF, Sublessor and Sublessee have executed this
Amendment on the dates set out below.

SUBLESSOR:                               SUBLESSEE:

COULTER PHARMACEUTICAL, INC.,            AXYS PHARMACEUTICALS, INC.,
a Delaware corporation                   a Delaware corporation

        /s/ Steven Gillis, Ph.D.                 /s/ John S. Ostaszewski
By: _________________________________    By:  ________________________________

        President                                Treasurer
Title: ______________________________    Title: ______________________________

        September 29, 2003                       September 26, 2003
Date: _______________________________    Date: _______________________________

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                                    EXHIBIT A

                                      LEASE

[Lease Agreement dated as of May 19, 2000, between HMS Gateway Office, L.P. and
Coulter Pharmaceutical, Inc. was filed with the Commission on June 24, 2002, as
Exhibit 10.72 to the Amended Annual Report on Form 10-K/A for Corixa Corporation
(File No. 000-22891)]

[First Amendment to Lease Agreement dated as of January 15, 2002; between HMS
Gateway Office, L.P. and Coulter Pharmaceutical, Inc. was filed with the
Commission on February 25, 2003, as Exhibit 10.76 to the Annual Report on Form
10-K for Corixa Corporation (File No. 000-22891)]