Stelios Papadopoulos, Ph.D., a co-founder of Exelixis, has been a director since December 1994 and the Chairman of the Board since January 1998. Dr. Papadopoulos retired as Vice Chairman of Cowen & Co., LLC in August 2006 after six years as an investment banker with the firm, where he focused on the biotechnology and pharmaceutical sectors. Prior to joining Cowen & Co., he spent 13 years as an investment banker at PaineWebber, Incorporated, where he was most recently Chairman of PaineWebber Development Corp., a PaineWebber subsidiary focusing on biotechnology. He joined PaineWebber in April 1987 from Drexel Burnham Lambert, where he was a Vice President in the Equity Research Department covering the biotechnology industry. Prior to Drexel, he was a biotechnology analyst at Donaldson, Lufkin & Jenrette. Before coming to Wall Street in 1985, Dr. Papadopoulos was on the faculty of the Department of Cell Biology at New York University Medical Center. He continues his affiliation with New York University Medical Center as an Adjunct Associate Professor of Cell Biology. Dr. Papadopoulos is a co-founder of Anadys Pharmaceuticals, Inc., a publicly-held drug discovery and development company acquired by Hoffmann-La Roche Inc. in November 2011. Dr. Papadopoulos served as a member of the board of directors of Anadys Pharmaceuticals from 2000 to 2011 and as its chairman in 2011 prior to its acquisition. Dr. Papadopoulos has served as a member of the board of directors of BG Medicine, Inc., a publicly-held life sciences company, since 2003. Dr. Papadopoulos previously served as a member of the board of directors of GenVec, Inc., a publicly-held biotechnology company from August 2003 until October 2006 and as a member of the board of directors of SGX Pharmaceuticals, Inc. from July 2001 to September 2006 prior to its acquisition by Eli Lilly and Company. Dr. Papadopoulos is a co-founder and member of the board of directors of Cellzome Inc., a privately-held drug discovery company, a member of the board of directors of Joule Unlimited, Inc., a privately-held biotechnology company and a member of the board of directors of Regulus Therapeutics Inc., a privately-held biotechnology company. Dr. Papadopoulos holds a Ph.D. in Biophysics and an M.B.A. in Finance, both from New York University.