Thousand Oaks, CA – August 27, 2003 – Amgen Inc. (NASDAQ: AMGN) announced today that the Company has settled its patent litigation with Genentech, Inc. (NYSE: DNA) in the U.S. District Court for the Northern District of California. In that suit, Genentech alleged that Amgen's process for producing Neupogen® and Neulasta®, drugs developed by Amgen to decrease the incidence of infection during many types of cancer-related chemotherapy, infringed certain Genentech patents.

Under the settlement agreement, both parties agreed to dismiss their claims and counterclaims against each other. The settlement includes a one-time payment to Genentech. Amgen is not taking a license under any Genentech patents. Financial terms of the settlement were not disclosed. Amgen expects the financial impact of the settlement to be less than $0.05 per share on a GAAP basis and this non-recurring charge will be recorded in the third quarter.

This news release contains forward-looking statements that involve significant risks and uncertainties, including those discussed below and others that can be found in our Form 10-K for the year ended December 31, 2002, and in our periodic reports on Form 10-Q and Form 8-K. Amgen is providing this information as of the date of this news release and does not undertake any obligation to update any forward-looking statements contained in this document as a result of new information, future events or otherwise.

No forward-looking statement can be guaranteed and actual results may differ materially from those we project. The Company's results may be affected by our ability to successfully market both new and existing products domestically and internationally, sales growth of recently launched products, difficulties or delays in manufacturing our products, and regulatory developments (domestic or foreign) involving current and future products and manufacturing facilities. In addition, sales of our products are affected by reimbursement policies imposed by third party payors, including governments, private insurance plans and managed care providers, and may be affected by domestic and international trends toward managed care and healthcare cost containment as well as possible US legislation affecting pharmaceutical pricing and reimbursement. Government regulations and reimbursement policies may affect the development, usage and pricing of our product. Furthermore, our research, testing, pricing, marketing and other operations are subject to extensive regulation by domestic and foreign government regulatory authorities. We, or others could identify side effects or manufacturing problems with our products after they are on the market. In addition, we compete with other companies with respect to some of our marketed products as well as for the discovery and development of new products. Discovery or identification of new product candidates cannot be guaranteed and movement from concept to product is uncertain; consequently, there can be no guarantee that any particular product candidate will be successful and become a commercial product. In addition, while we routinely obtain patents for our products and technology, the protection offered by our patents and patent applications may be challenged, invalidated or circumvented by our competitors. Further, some raw materials, medical devices, and component parts for our products are supplied by sole third party suppliers. Amgen is a global biotechnology company that discovers, develops, manufactures and markets important human therapeutics based on advances in cellular and molecular biology.

For more information, please contact:
Amgen, Thousand Oaks
Media: 805/447-4587
Investors: 805-447-1060