Exelixis, Inc. To Host Clinical Investigator Discussions Of Preliminary Phase I Trial Results Of XL647, XL880 And XL999

SOUTH SAN FRANCISCO, Calif., Nov. 2 /PRNewswire-FirstCall/ -- Exelixis, Inc. announced today that it will host two briefings to summarize and discuss preliminary data from the Phase I trials of XL647, XL880 and XL999 at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics. Leading clinical investigators will review the trial results in the context of other investigational agents.

XL647 and XL880 Phase I Clinical Trial Data Summary Date: Tuesday, November 15, 2005 Time: 8:00 PM (EST) - 9:30 PM (EST) Location: The Rittenhouse Hotel, Grand Salon 210 West Rittenhouse Square Philadelphia, PA 19103 Webcast: http://www.investorcalendar.com/IC/CEPage.asp?ID=97411 Dial in: U. S.: 877-407-8033 Int'l: 201-689-8033 Speakers: Anthony W. Tolcher, MD, FRCPC Director of Clinical Research, Institute for Drug Development Patricia LoRusso, DO Professor of Medicine and Oncology, Wayne State University, Karmanos Cancer Center XL999 Phase I Clinical Trial Data Summary Date: Thursday, November 17, 2005 Time: 8:00 PM (EST) - 9:30 PM (EST) Location: The Rittenhouse Hotel, Grand Salon 210 West Rittenhouse Square Philadelphia, PA 19103 Webcast: http://www.investorcalendar.com/IC/CEPage.asp?ID=97412 Dial in: U. S.: 877-407-8033 Int'l: 201-689-8033 Speaker: Anthony W. Tolcher, MD, FRCPC Director of Clinical Research, Institute for Drug Development About Exelixis

Exelixis, Inc. is a biotechnology company dedicated to the discovery and development of novel therapeutics that will potentially enhance the care and lives of patients with cancer and other serious diseases. The company is leveraging its fully integrated gene-to-drug platform to fuel the growth of its proprietary drug pipeline. Exelixis' development pipeline covers cancer and metabolism and is comprised of the following compounds: XL119 (becatecarin), for which a multinational Phase III clinical trial in bile duct tumor is ongoing and which has been exclusively licensed to Helsinn Healthcare S.A. with rights to reacquire commercial rights for North America; XL784, which is being advanced as a treatment for renal disease and is currently in a Phase I clinical trial using a newly developed capsule formulation of the compound; XL647, XL999, XL880, XL820, XL844 and XL184, anticancer compounds currently in Phase 1 clinical trials; and multiple compounds in preclinical development for diseases including cancer and various metabolic and cardiovascular disorders. Exelixis has established broad corporate alliances with major pharmaceutical and biotechnology companies including GlaxoSmithKline (GSK) and Bristol-Myers Squibb Company. Pursuant to a product development and commercialization agreement between Exelixis and GSK, GSK has the option, after completion of Phase 2a clinical trials by Exelixis, to elect to develop a certain number of compounds in Exelixis' product pipeline, which may include XL784 and the cancer compounds identified in this press release (other than XL119), thus potentially triggering milestone payments and royalties from GSK and co-promotion rights by Exelixis. For more information, please visit the company's web site at www.exelixis.com.

CONTACT: Charles Butler, Associate Director, Corporate Communications ofExelixis, Inc., +1-650-837-7277, or cbutler@exelixis.com

Web site: http://www.exelixis.com/