EX-1 3 a2089391zex-1.htm EXHIBIT 1
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EXHIBIT 1

AGREEMENT REGARDING JOINT FILING

        The undersigned, Biotechnology Value Fund, L.P., a Delaware limited partnership, Biotechnology Value Fund II, L.P., a Delaware limited partnership, BVF Investments, L.L.C., a Delaware limited liability company, BVF Partners L.P., a Delaware limited partnership, and BVF Inc., a Delaware corporation, hereby agree and acknowledge that the information required by this Amendment to Schedule 13D, to which this Agreement is attached as an exhibit, is filed on behalf of each of them. The undersigned further agree that any amendments or supplements thereto shall also be filed on behalf of each of them.

Dated: September 16, 2002  
           
  BIOTECHNOLOGY VALUE FUND, L.P.  
           
  By: BVF Partners L.P., its general partner  
           
    By: BVF Inc., its general partner  
           
      By: /s/  MARK N. LAMPERT      
Mark N. Lampert
President		  
           
  BIOTECHNOLOGY VALUE FUND II, L.P.  
           
  By: BVF Partners L.P., its general partner  
           
    By: BVF Inc., its general partner  
           
      By: /s/  MARK N. LAMPERT      
Mark N. Lampert
President		  
           
  BVF INVESTMENTS L.L.C.  
           
  By: BVF Partners L.P., its manager  
           
    By: BVF Inc., its general partner  
           
      By: /s/  MARK N. LAMPERT      
Mark N. Lampert
President		  
           
  BVF PARTNERS L.P.  
           
  By: BVF Inc., its general partner  
           
    By: /s/  MARK N. LAMPERT      
Mark N. Lampert
President		  
           
  BVF INC.  
           
  By: /s/  MARK N. LAMPERT      
Mark N. Lampert
President		  
           


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AGREEMENT REGARDING JOINT FILING