Gilead Sciences Announces Degussa Corporation Will Acquire Gilead's 49 Percent Interest in Proligo L.L.C.

Foster City, CA -- August 22, 2001

Gilead Sciences, Inc. (Nasdaq:GILD) today announced that Degussa Corporation, based in Parsippany, New Jersey, will acquire Gilead's 49 percent interest in Proligo L.L.C. for approximately $14 million in cash. Proligo is a joint venture, focused on the manufacturing of oligonucleotides, between Gilead and SKW Americas, Inc. SKW Americas, a subsidiary of Degussa Corporation, holds the remaining 51 percent of Proligo. The deal is expected to close on August 31, 2001, and the proceeds net of Gilead's investment in Proligo will be reflected as a gain on the sale of a minority interest in a subsidiary in Gilead's third quarter 2001 financial results. The gain on the sale is estimated to be between $7.0 to $9.0 million.

Proligo was formed in 1998 by a joint venture between NeXstar Pharmaceuticals (now Gilead) and SKW Americas to provide nucleic acid products for genomics and genetic medicines. Proligo sells standard and specialty monomers for oligonucleotide synthesis, as well as advanced oligonucleotide probes. Proligo also provides custom manufacturing services for oligonucleotide therapeutics. As a result of Gilead's merger with NeXstar Pharmaceuticals in July 1999, Degussa Corporation became entitled to purchase Gilead's interest in Proligo for an agreed upon price.

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.

Degussa Corporation, located in Parsippany, New Jersey, is a specialty chemicals company with major businesses dedicated to health and nutrition, construction chemicals, fine and industrial chemicals, performance chemicals, coatings and advanced fillers, and specialty polymers. The company owns and operates production facilities, R & D and applied technology centers throughout the NAFTA region. Degussa Corporation is the North American subsidiary of Degussa AG, headquartered in Dusseldorf, Germany.