Cytokinetics and GlaxoSmithKline Form Major Strategic Alliance in Cancer Drug Discovery

Collaboration Establishes Leading Program in Emerging Field

South San Francisco, CA and London, UK - June 25, 2001

Cytokinetics, Inc., and GlaxoSmithKline plc (GSK) announced today that the two companies have entered into a broad strategic collaboration to discover, develop and commercialize novel small-molecule therapeutics targeting mitotic kinesins for applications in the treatment of cancer and other diseases.

Under the terms of the agreements, GSK has committed funding of approximately $50 million over the minimum 5-year research term, including a $14 million upfront cash payment and a $14 million purchase of Cytokinetics preferred stock. In addition, GSK could make milestone payments to Cytokinetics ranging from $30-50 million per target for products directed to each of over 10 mitotic kinesins that will be the subject of collaborative activities. GSK is responsible for worldwide development and commercialization of products arising from the collaboration. Cytokinetics will receive royalties from the sale of any resulting products. In addition, Cytokinetics retains a product-by-product option to co-fund certain development activities, thereby increasing its royalty and affording co-promotion rights in North America. During the collaboration, targets may revert to Cytokinetics for independent research and development, with GSK retaining an option to resume joint activities. The Collaboration and License and Stock Purchase Agreements are subject to Hart-Scott-Rodino clearance.

"We are excited to be working with GlaxoSmithKline toward the broad exploitation of this field," stated Dr. James Sabry, Cytokinetics' President and Chief Executive Officer. "Their leadership within the pharmaceutical arena in general and oncology specifically combined with our franchise position in mitotic kinesins should powerfully enable the translation of this important research into novel therapies in cancer. The magnitude and innovative structure of this alliance reinforces the enthusiasm we both share for this area."

"Recognizing the significant opportunity presented by mitotic kinesin inhibitors, we are eager to bring our capabilities together with Cytokinetics' expertise in this area to develop novel therapeutics," said Dr. Allen Oliff, GSK's Senior Vice President, Center of Excellence for Drug Discovery - Oncology, Cardiovascular & Genitourinary. "This collaboration is proof-positive of our commitment to new approaches in small-molecule drug discovery for oncology."

Mitotic kinesins are a family of cytoskeletal enzymes that perform essential roles in mitotic spindle formation and function during cell division. Inhibition of mitotic kinesins disrupts the cell cycle, thereby inducing apoptosis or cell death. Existing anti-mitotic drugs account for over $2 billion annually in worldwide anti-cancer pharmaceutical sales and, despite certain mechanistic limitations that account for drug-related side effects, represent the most commercially successful therapies in today's cancer marketplace. Because mitotic kinesin inhibitors differ from existing anti-mitotic drugs in their molecular target and mechanism of action, they are being investigated for the potential to demonstrate an improved therapeutic profile. If this potential is fulfilled, mitotic kinesin inhibitors would offer the first novel mechanism of action in this category of cancer therapy in over 25 years.

In this collaboration, Cytokinetics will combine its foremost position in the biology and pharmacology of mitotic kinesins with the advanced pharmaceutical discovery, development, and commercialization capabilities of GSK to build the leading initiative in this field. In particular, the companies will employ a multi-pronged approach utilizing focused genomics, high throughput screening (including Cytokinetics' PUMA™ technologies), automated cell-based secondary characterization technologies (including Cytokinetics' Cytometrix™ cellular phenotyping technologies), structural biology and medicinal chemistry to identify, characterize and optimize small molecule inhibitors of the mitotic kinesin targets that have formed the cornerstone of the Cytokinetics program to date. In addition, the companies will be seeking to further optimize and develop existing lead candidates identified at Cytokinetics, including one mitotic kinesin inhibitor that has demonstrated anti-tumor activity in a broad array of in vivo tumor models and for which Cytokinetics initiated pre-clinical development activities earlier this year. In all, the collaboration anticipates several drug candidates emerging from joint activities.

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 that impacts all aspects of cell function including cell division, cell motility, intracellular transport, muscle contractility and regulation of cellular organization. Cytokinetics' R&D efforts incorporate proprietary Cytometrix™ automated cell biology technologies and are focused on serving pharmaceutical needs in cancer, cardiovascular and infectious diseases.

About GlaxoSmithKline
GlaxoSmithKline - one of the world's leading research-based pharmaceutical and healthcare companies - is committed to improving the quality of human life by enabling people to do more, feel better and live longer.