Press Release

Exelixis Announces March 17 Webcast of Presentation at the Cowen and Company Annual Health Care Conference

March 12, 2008

SOUTH SAN FRANCISCO, Calif., March 12 /PRNewswire-FirstCall/ -- Exelixis, Inc. (Nasdaq: EXEL) announced today that George A. Scangos, PhD, president and chief executive officer of Exelixis, will present at the Cowen and Company Annual Health Care Conference at 4:00 p.m. ET / 1:00 p.m. PT on Monday, March 17, 2008. Dr. Scangos will discuss updates to the company's development pipeline and corporate strategy.

The presentation will be webcast and may be accessed in the Event Calendar page under Investors on the Exelixis website at http://www.exelixis.com.

About Exelixis

Exelixis, Inc. is a development-stage biotechnology company dedicated to the discovery and development of novel small molecule therapeutics for the treatment of cancer and other serious diseases. The company is leveraging its fully integrated drug discovery platform to fuel the growth of its development pipeline, which is primarily focused on cancer. Currently, Exelixis' broad product pipeline includes investigational compounds in phase 2 and phase 1 clinical development. Exelixis has established strategic corporate alliances with major pharmaceutical and biotechnology companies, including GlaxoSmithKline, Bristol-Myers Squibb Company, Genentech, Wyeth Pharmaceuticals and Daiichi-Sankyo. For more information, please visit the company's web site at http://www.exelixis.com.

SOURCE Exelixis, Inc.

CONTACT:
investors, Charles Butler,
Senior Director,
Corporate Communications & Investor Relations,
+1-650-837-7277,
cbutler@exelixis.com;
or
media, Soleil Maxwell Harrison,
Senior Manager,
Corporate Communications,
+1- 650-837-7012,
sharrison@exelixis.com,
both of Exelixis, Inc.

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