FDA Posts Background Documents for October 3 Viread™ Advisory Committee Meeting

Foster City, CA -- October 2, 2001

Gilead Sciences, Inc. (Nasdaq: GILD) today announced that the U.S. Food and Drug Administration (FDA) posted on its web site (www.fda.gov) the agency's background package related to the company's New Drug Application (NDA) for Viread™ (tenofovir disoproxil fumarate). These documents include the company's and FDA's background summaries for the October 3, 2001 Antiviral Drugs Advisory Committee hearing at which the Viread NDA will be reviewed. The hearing is an open, public forum for presentation and discussion of relevant scientific information contained in the Viread NDA.

Viread is an investigational antiretroviral agent for the treatment of HIV infection that was granted a six-month priority review by the FDA. Viread is dosed as a single 300 mg tablet taken once daily and works by blocking reverse transcriptase, an enzyme crucial to the replication of HIV. Gilead also has filed regulatory applications for Viread in the European Union and Australia. As an investigational drug, Viread has not yet been determined safe or efficacious in humans for its ultimate intended use.

Gilead Sciences, Inc., headquartered in Foster City, CA, is an independent biopharmaceutical company that seeks to provide accelerated solutions for patients and the people who care for them. Gilead discovers, develops, manufactures and commercializes proprietary therapeutics for challenging infectious diseases (viral, fungal and bacterial infections) and cancer. Gilead maintains research, development or manufacturing facilities in the United States, Europe and Australia.

This press release includes forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995, that are subject to risks, uncertainties and other factors that could cause actual results to differ materially from those referred to in the forward-looking statements. Such risks and uncertainties include risks related to regulatory approval of Viread. The reader is cautioned not to rely on these forward-looking statements. These and other risks are described in detail in the Gilead Annual Report on Form 10-K for the year ended December 31, 2000 and in Gilead's Quarterly Reports on Form 10-Q, all of which are on file with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead and Gilead assumes no obligation to update any such forward-looking statements.