South San Francisco, California
May 21,  2001

Exelixis, Inc. (Nasdaq: EXEL) today announced that Bayer has accepted additional assays for high-throughput screening from Genoptera LLC, its joint venture with Bayer's crop protection division. The delivery of these assays triggers undisclosed milestone payments to Exelixis. 

"Genoptera continues to set high standards for the identification of unique, highly validated targets and assays for delivery to our partner Bayer," stated George Scangos, Ph.D., president and chief executive officer of Exelixis, Inc. "The productivity of the collaboration in transferring new targets into test systems for Bayer's Ultra High-Throughput Screening thus far has been exceptional and we look forward to continued success with this alliance." 

Formed in January 2000, Genoptera LLC focuses on the discovery of novel insecticides and nematicides. The joint venture is a continuation and expansion of the collaboration that Exelixis and Bayer initially established in April 1998 and expanded in June 1999. In addition to $80 million in committed research funding over the course of the eight-year joint venture, the arrangement involves a $20 million up-front payment and performance-based milestone and royalty payments to Exelixis. Bayer has the exclusive right to commercialize insecticides based on technology developed by Genoptera. 

Exelixis, Inc. is a leading life sciences biotechnology company focused on product development through its expertise in comparative genomics and model system genetics. These technologies provide a rapid, efficient and cost effective way to move from DNA sequence data to knowledge about the function of genes and the proteins they encode. The company's technology is broadly applicable to all life sciences industries including pharmaceutical, diagnostic, agricultural biotechnology and animal health. Exelixis has partnerships with Aventis, Bayer, Pharmacia, Bristol-Myers Squibb and Dow AgroSciences and is building its internal development program in the area of oncology.

Exelixis and the Exelixis logo are registered U.S. trademarks. 

Company news release
N3541