Gilead Sciences Announces Acceptance of Late Breaker Abstract at Upcoming ICAAC Meeting

Forty-eight Week Data from Phase III Study of Adefovir Dipivoxil 10 mg to be Presented

Foster City, CA -- September 6, 2001

Gilead Sciences (Nasdaq: GILD) today announced that 48-week clinical data from a Phase III study of its investigational drug, adefovir dipivoxil 10 mg for chronic hepatitis B virus (HBV) infection, will be presented in a late breaker presentation at the 41st Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) taking place in Chicago, Illinois, from September 22-25, 2001. These data were summarized in a Gilead press release issued on June 22, 2001.

Clinical investigator Seng Gee Lim, MD, Division of Gastroenterology, Department of Medicine, National University Hospital, Singapore, will present 48-week safety and efficacy data from Gilead's first pivotal clinical trial, Study 437, of adefovir dipivoxil in 515 patients with chronic HBV infection. These data will be presented on Sunday, September 23 in Late Breaker Session #91 (Abstract #41273) between 12:00 p.m. - 1:30 p.m. Central Time.

In addition, Gilead's marketed and investigational products will be the subject of 15 posters or presentations during the ICAAC conference. Cubist Pharmaceuticals will have 24 Cidecin® (daptomycin for injection) and daptomycin-related posters or presentations at the conference. Gilead entered into a partnership with Cubist in January 2001 granting Gilead exclusive rights to commercialize Cubist's investigational antibacterial drug Cidecin in Europe following regulatory approval. A schedule of presentations may be obtained from the Gilead Web site at www.gilead.com. Late breaker abstracts will be made available to conference participants upon registration at the meeting.

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 Foster City, CA; Boulder, CO; San Dimas, CA; Cambridge, UK and Dublin, Ireland and sales and marketing organizations in the United States, Europe and Australia.