Exelixis And Cytokinetics Establish Chemistry Collaboration

South San Francisco, CA - January 3, 2002

Exelixis, Inc. (Nasdaq: EXEL) and Cytokinetics jointly announced that they have entered into a collaboration to design and generate diverse, small molecule compound libraries that each company will use to further advance its own drug discovery programs. This alliance marks the third chemistry-based partnership for Exelixis established during 2001.

Under the agreed terms, Exelixis will use its proprietary combinatorial chemistry platform to synthesize compounds designed jointly by the two companies. The compounds will be jointly owned and each company will have the right to use the compounds in its own internal lead discovery as well as in collaborative research efforts. Exelixis will receive undisclosed cash payments for the compounds delivered to Cytokinetics under the collaboration.

"In a very short period of time, Exelixis has built a robust chemistry program that is an asset for generating novel, high quality compounds to advance our internal discovery efforts and for corporate partnering,” said George A. Scangos, Ph.D., president and chief executive officer of Exelixis. “This important alliance with Cytokinetics underscores our expertise in all facets of production, including analytics, informatics, and formatting. The compounds generated through this collaboration have the potential to benefit both companies’ pipelines.”

"We are pleased to enter into this partnership with Exelixis, which will augment the diversity of each company’s compound libraries furthering the pursuit of each of our novel therapeutic discovery programs,” said James H. Sabry, M.D., Ph.D., president and chief executive officer of Cytokinetics. “We are confident that by significantly expanding our high throughput chemical screening library, we will also be leveraging our investments in cytoskeletal biology towards small molecule pharmaceuticals that will address a variety of important clinical markets.”

About Cytokinetics
Founded in 1998 and privately-held, Cytokinetics is dedicated to the discovery, development and commercialization of a novel class of therapeutics resulting from its leadership position in the emerging field of cytoskeletal pharmacology. The cytoskeleton is a complex, dynamic framework of proteins that is essential for many aspects of cell function including cell division, cell motility, intracellular transport, muscle contractility and regulation of cellular organization. Cytokinetics’ R&D efforts incorporate proprietary CytometrixTM automated cell biology technologies and are focused on serving pharmaceutical needs in cancer, cardiovascular and infectious diseases. In June 2001, Cytokinetics entered into a major collaboration in oncology with GlaxoSmithKline to research, develop and co-commercialize products that are inhibitors of mitotic kinesin motor proteins. The first drug candidate to be developed under this collaboration is scheduled to enter clinical trials in 2002. For more information, please visit the company’s web site at www.cytokinetics.com.

About Exelixis
Exelixis, Inc. is a leading genomics-based drug discovery 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 CropScience S.A., Bayer Corporation, Bristol-Myers Squibb Company, Elan Pharmaceuticals, Inc., Pharmacia Corporation, Protein Design Labs, Inc., Scios Inc. and Dow AgroSciences LLC, and is building its internal development program in the area of oncology. For more information, please visit the company’s web site at www.exelixis.com.