Dennis D. Keith, Ph.D. has served as our Vice President, Chemistry since July 2000. From October 1997 to July 2000, he served as our Vice President, Drug Discovery. From 1971 to October 1997, Dr. Keith was with Hoffmann-La Roche Inc. where he served in various positions, including Director of Anti-infective Chemistry, Senior Director of Medicinal Chemistry and Research Director of Oncology. Dr. Keith received his B.S. in Chemistry from Bates College and his Ph.D. in Organic Chemistry from Yale University.