Letter Amendment dated as of August 21, 2003, to the Amended and Restated Collaboration
      Agreement between Genentech, Inc. and Idec Pharmaceuticals Corporation.


    
      
        

      


      EXHIBIT 10.3

      


      


      LETTER
        AMENDMENT TO AGREEMENT

      


      This
        Letter Amendment to the Agreement (as defined below) (the “Letter Amendment”)
        effective as of August 21, 2003 (the “Letter Amendment Effective Date”), is
        entered into by and between IDEC
        PHARMACEUTICALS
        CORPORATION,
        a Delaware corporation having its principal place of business at 3030 Callan
        Road, San Diego, California 92121 ("IDEC") and GENENTECH,
        INC., a
        Delaware corporation having its principal place of business at 1 DNA Way,
        South
        San Francisco, California 94080 ("Genentech"), each on behalf of itself and
        its
        Affiliates.

      


      WHEREAS,
        the parties to this Agreement entered into that certain “Amended and Restated
        Collaboration Agreement” of June 19, 2003 (the “Agreement”); and 

      


      WHEREAS,
        the parties wish to enter into an amendment to the Agreement in order to
        amend
        certain rights therein.

      


      NOW
        THEREFORE, for and in consideration of the covenants, conditions, and
        undertakings hereinafter set forth it is agree by and between the parties
        as
        follows:

      


      1.  All
        capitalized terms not defined in this Letter Amendment shall have the meanings
        given to them in the Agreement.

      


      2.  With
        respect to any disputes arising under the Agreement that are to be referred
        to
        the parties respective chief executive officers in accordance with Section
        17.1,
        notwithstanding such provision, it is understood and agreed that such disputes
        shall instead be referred to William H. Rastetter (on behalf of IDEC or its
        successor) and Arthur D. Levinson (on behalf of Genentech or its successor),
        in
        each case, for so long as such person remains in the employment of such party
        (or its successor).

      


      3.  This
        Letter Amendment may be terminated by either party at any time prior to the
        expiration of the Agreement, which termination shall be effective upon receipt
        of such notice by the other party.

      


      4.  Except
        as specifically modified or amended hereby, the Agreement shall remain in
        full
        force and effect and, as modified or amended, is hereby ratified, confirmed
        and
        approved. No provision of this Letter Amendment may be modified or amended
        except expressly in a writing signed by both parties nor shall any terms
        be
        waived except expressly in a writing signed by the party charged therewith.
        This
        Letter Amendment shall be governed in accordance with the laws of the State
        of
        California, without regard to principles of conflicts of laws.

      


      IN
        WITNESS
        WHEREOF,
        the
        parties have executed this Letter Amendment in duplicate originals by their
        proper officers as of the date and year first above written.

      


      
        	 	
                IDEC
                  PHARMACEUTICALS CORPORATION

              	 	
                GENENTECH,
                  INC.

              
	 	 	 	 	 	 
	 	
                By:

              	
                 /s/ WILLIAM
                  H. RASTETTER

              	 	
                By:

              	
                 /s/ ARTHUR
                  D. LEVINSON

              
	 	 	
                William
                  H. Rastetter

                Title:  Chairman
                  and CEO

              	 	 	
                Arthur
                  D. Levinson

                Title:  Chairman
                  and CEO