Amgen Opens State-of-the-Art Biotechnology Research Campus

                      40-Acre Seattle Campus Focuses On
                  Advancing Cancer and Immunology Therapies

SEATTLE, Feb. 25 -- Amgen Inc. (Nasdaq: AMGN), the world's largest biotechnology company, today announced the official opening of its new state-of-the-art research and development campus. The 750,000 square foot facility was designed in collaboration with scientists as an environment for the creation of breakthrough therapies. Helix will house researchers, process development scientists and support personnel. The completion of the Helix campus, located on the waterfront of Seattle's Interbay neighborhood, reflects the company's commitment to continuing the growth of the biotech industry in the region.

More than 750 staff from several locations throughout Seattle are scheduled to move into the new $625 million Helix campus, which includes the latest technological advances in computerization and robotics to maximize efficiencies in research and process development. "Amgen's state-of-the-art biotechnology campus, the largest of its kind in the Northwest, is designed to optimize scientific exploration, discovery and collaboration," said Roger M. Perlmutter, M.D., Ph.D., executive vice president of Research and Development. "Ultimately, we're looking to accelerate the drug discovery process in order to deliver groundbreaking inflammation and oncology therapies to patients as quickly as possible," added Perlmutter. The location of the campus will further enhance scientific learning by increasing opportunities for Amgen scientists to collaborate with leading Seattle research centers such as the University of Washington, the Fred Hutchinson Cancer Research Center, and the Institute for Systems Biology.

About the Campus

The 40-acre campus houses six buildings including lab and supporting office space, totaling 750,000 square feet. Additionally, Amgen built an adjacent award-winning pedestrian bridge to provide staff and local residents with direct access to waterfront parks. A substantial portion of the facility has been set aside as green space with extensive landscaping that complements the waterfront location.

About Amgen

Amgen is a global biotechnology company that discovers, develops, manufactures and markets important human therapeutics based on advances in cellular and molecular biology.

FORWARD LOOKING STATEMENTS

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 U.S. legislation affecting pharmaceutical pricing and reimbursement. Government regulations and reimbursement policies may affect the development, usage and pricing of our products. 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.

CONTACT: Amgen, Thousand Oaks
Mary Klem: (805) 447-4587 (media)
Cary Rosansky: (805) 447-1060 (investors)

Helix Campus, Seattle
Carol Pawlak: (206) 579-0654 (Washington media)

NOTE TO EDITORS: An electronic version of this news release may be accessed via our Web site at www.amgen.com . Journalists and media representatives may sign up to receive all news releases electronically at time of announcement by filling out a short form in the Media section of the Web site