Board of Directors

Alexander E. Barkas, Ph.D., has served as Chairman of the Board since July 1993 and as a director of the Company since March 1992. From March 1992 until May 1993, he served as President and Chief Executive Officer of the Company. Dr. Barkas is a Managing Director of Prospect Venture Partners, a venture capital firm. Prior to co-founding Prospect Venture Partners I, II and III, he was a partner at Kleiner Perkins Caufield & Byers (Kleiner Perkins) from 1991 to 1997, where he focused on healthcare product company investments. Prior to Kleiner Perkins, Dr. Barkas was a founder and CEO of BioBridge Associates, a health care industry consulting firm. Dr. Barkas is currently Chairman of the Board of Tercica, Inc., and serves on the board of directors of Amicus Therapeutics, Inc. and several private life science companies. Dr. Barkas received a Ph.D. in biology from New York University and a B.A. in Biology from Brandeis University, where he currently is Chairman of the University Science Advisory Council and serves on the Board of Trustees.

Edward V. Fritzky, has served as a director of the Company since July 1998. He served as a director and advisor to Amgen Corporation from July 2002 to May 2005. He served as Chief Executive Officer and Chairman of Immunex Corporation from January 1994 to July 2002. Mr. Fritzky is also a director of Sonosite, Inc. and Jacobs Engineering Group, Inc. Mr. Fritzky served as President of Lederle Laboratories, a division of American Cyanamid, from 1992 to 1994, and as Vice President of Lederle Laboratories from 1989 to 1992. Prior to joining Lederle Laboratories, Mr. Fritzky was an executive of Searle Pharmaceuticals, Inc., a subsidiary of the Monsanto Company. During his tenure at Searle, Mr. Fritzky was Vice President of Marketing in the United States, and later President and General Manager of Searle Canada, Inc. and Lorex Pharmaceuticals, a joint venture company. Mr. Fritzky served as a Trustee of the Fred Hutchinson Cancer Center. Mr. Fritzky holds a B.A. from Duquesne University and is a graduate of the Advanced Executive Program, J.L. Kellogg Graduate School of Management at Northwestern University.

Charles J. Homcy, M.D., has served as a director of the Company since July 2005 and is currently President and Chief Executive Officer of Portola Pharmaceuticals, Inc. From January 2003 to November 2003, Dr. Homcy served as senior R&D advisor at Millennium Pharmaceuticals, having joined them in 2002 as President, Research and Development. Prior to that, he served as Executive Vice President, Research and Development of COR Therapeutics, Inc. from 1995 to 2002 and as a director of COR from January 1998 to 2002. Since 1997, Dr. Homcy has been Clinical Professor of Medicine, University of California at San Francisco Medical School and attending physician at the San Francisco VA Hospital. From 1994 until 1995, Dr. Homcy was president of the medical research division of American Cyanamid Company-Lederle Laboratories (now a division of Wyeth-Ayerst Laboratories). From 1990 until 1994, Dr. Homcy was executive director of the cardiovascular and central nervous system research section at Lederle Laboratories. From 1991 to 1995, Dr. Homcy also served as attending physician at The Presbyterian Hospital, College of Physicians and Surgeons, at Columbia University in New York. From 1979 to 1990, he was attending physician at Massachusetts General Hospital and an Associate Professor of Medicine at Harvard Medical School. Dr. Homcy is also a member of the board of directors of Millennium Pharmaceuticals, Cytokinetics and Kosan Biosciences. Dr. Homcy received his B.A. and M.D. degrees from The Johns Hopkins University in Baltimore.

Thomas D. Kiley, Esq., has served as a director of the Company since September 1992. Mr. Kiley is also a director of certain privately held biotechnology and other companies. He has been self-employed since 1988 as an attorney, consultant and investor. From 1980 to 1988, he was an officer of Genentech, Inc., a biotechnology company, serving variously as Vice President and General Counsel, Vice President for Legal Affairs and Vice President for Corporate Development. From 1969 to 1980, he was with the Los Angeles law firm of Lyon & Lyon and was a partner at the firm from 1975 to 1980. Mr. Kiley holds a B.S. in Chemical Engineering from Pennsylvania State University and a J.D. from George Washington University.

Thomas B. Okarma, Ph.D., M.D., has served as President, Chief Executive Officer and a member of the board of directors since July 1999. He is also a director of Geron Bio-Med Limited, a United Kingdom company and Geron's wholly-owned subsidiary, and TA Therapeutics, Ltd., a Hong Kong company and Geron's majority-owned subsidiary. From May 1998 until July 1999, Dr. Okarma was the Vice President of Research and Development. From December 1997 until May 1998, Dr. Okarma was Vice President of Cell Therapies. Dr. Okarma currently serves on the Board of BIO and was Chairman of the Board of Overseers of Dartmouth Medical School from 2000 to 2007. From 1985 until joining us, Dr. Okarma, the scientific founder of Applied Immune Sciences, Inc., served initially as Vice President of Research and Development of Applied Immune Sciences and then as chairman, chief executive officer and a director of Applied Immune Sciences, until 1995 when it was acquired by Rhone-Poulenc Rorer. Dr. Okarma was a Senior Vice President at Rhone-Poulenc Rorer from the time of the acquisition of Applied Immune Sciences until December 1996. From 1980 to 1992, Dr. Okarma was a member of the faculty of the Department of Medicine at Stanford University School of Medicine. Dr. Okarma holds a A.B. from Dartmouth College, a M.D. and Ph.D. from Stanford University and an executive M.B.A. from Stanford Graduate School of Business.

John P. Walker, has served as a director of the Company since April 1997 and is currently the Chief Executive Officer and Chairman of the Board of Novacea, Inc. From 2001 to 2007, Mr. Walker acting as a consultant and investor has served as an Investment Advisor to MDS Capital Corporation, Interim Chief Executive Officer of KAI Pharmaceuticals, Chairman and Interim Chief Executive Officer at Guava Technologies, Chairman and Chief Executive Officer of Bayhill Therapeutics and Chairman and Interim Chief Executive Officer of Centaur, Inc. From 1993 to 2001, he was Chairman, Chief Executive Officer and a director of Axys Pharmaceuticals Inc. and its predecessor company, Arris Pharmaceutical Corporation. Prior to his association with Arris, Mr. Walker was the Chairman and Chief Executive Officer of Vitaphore Corporation, a biomaterials company which was sold to Union Carbide Chemical and Plastics Company Inc. in 1990. From 1971 to 1985, Mr. Walker was employed by American Hospital Supply Corporation in a variety of general management, sales and marketing positions, most recently serving as President of the American Hospital Company. Mr. Walker is an executive chairman and principal executive officer of Renovis, Inc. and director of Affymax, Inc. and certain other privately held biotechnology companies. He holds a B.A. from the State University of New York at Buffalo and is a graduate of the Advanced Executive Program, J.L. Kellogg Graduate School of Management at Northwestern University.

Patrick J. Zenner, has served as a director of the Company since July 2001. He is currently serving as interim Chief Executive Officer of Exact Sciences Corporation, a genomics-based biopharmaceutical company, and served as interim Chief Executive Officer for CuraGen Corporation from May 2005 through March 2006. From 1969 until January 2001, Mr. Zenner held a series of executive managerial positions with Hoffmann La-Roche, Inc., North America, the prescription drug unit of the Roche Group, a leading research-based health care enterprise. He retired as President and Chief Executive Officer in January 2001. He is also a director of Arqule, Inc., CuraGen Corporation, Exact Sciences Corporation, Sciele Pharma Inc., XOMA Ltd. and West Pharmaceutical Services. Mr. Zenner holds a B.S.B.A. from Creighton University and a M.B.A. from Fairleigh Dickinson University. He serves on the Board of Trustees for both universities and is Chairman of the Board for Fairleigh Dickinson University.