Press Release

Exelixis Announces September 3 Webcast of Presentation at the Thomas Weisel Partners 2008 Healthcare Conference

August 25, 2008

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Aug. 25, 2008--Exelixis, Inc. (Nasdaq:EXEL) announced today that Frank Karbe, Executive Vice President and Chief Financial Officer of Exelixis, will present at the Thomas Weisel Partners 2008 Healthcare Conference at 10:20 a.m. ET/7:20 a.m. PT on Wednesday, September 3, 2008. Mr. Karbe 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 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 3, phase 2, and phase 1 clinical development. Exelixis has established strategic corporate alliances with major pharmaceutical and biotechnology companies, including GlaxoSmithKline, Bristol-Myers Squibb, Genentech, Wyeth Pharmaceuticals, and Daiichi-Sankyo. For more information, please visit the company's web site at www.exelixis.com.

CONTACT: Exelixis, Inc.
Investor Contact:
Charles Butler, 650-837-7277
Senior Director Corporate Communications
& Investor Relations
cbutler@exelixis.com
Media Contact:
Soleil Maxwell Harrison, 650-837-7012
Senior Manager
Corporate Communications
sharrison@exelixis.com

SOURCE: Exelixis, Inc.