Amgen Signs Multi-Year Agreement With US Oncology for Aranesp, Neulasta and NEUPOGEN.

Business Editors

THOUSAND OAKS, Calif. and HOUSTON--(BUSINESS WIRE)--March 14, 2002

Amgen (Nasdaq:AMGN), the world's largest biotechnology company, has signed a multi-year agreement with US Oncology, Inc., (Nasdaq:USON), the nation's largest health-care network dedicated exclusively to cancer services and research. The agreement covers Aranesp(TM) (darbepoetin alfa), a new drug in the treatment for anemia, and Neulasta(TM) (pegfilgrastim) and NEUPOGEN(R) (Filgrastim), both of which reduce the risk of chemotherapy-induced neutropenia.

"US Oncology is always striving to provide patients access to the best and most effective cancer care possible," said Michael Louviere, vice president, US Oncology's Oncology Pharmaceutical Services division. "Aranesp, Neulasta and Neupogen are important tools that give our member physicians a wide variety of effective options for treating anemia and neutropenia and improve patient outcomes and quality of life."

"With Aranesp and Neulasta, Amgen is advancing the management of some of the most serious aspects of cancer care," said George Morrow, Amgen's executive vice president -- worldwide marketing and sales. "We continue to make rapid progress in bringing these benefits to physicians and patients across the country, and our relationship with US Oncology is the latest step in translating scientific advances into improved care for cancer patients."

Aranesp was approved by the U.S. Food and Drug Administration (FDA) in September 2001 for the treatment of anemia related to chronic renal failure for patients on dialysis and not on dialysis, and currently is under review by the FDA for use in cancer patients receiving chemotherapy.

Neulasta(TM) was approved by the FDA in January 2002 for decreasing the incidence of infection, as manifested by febrile neutropenia (fever associated with a severe drop in infection-fighting white blood cells) in patients with non-myeloid malignancies receiving myelosuppressive anti-cancer drugs associated with a clinically significant incidence of febrile neutropenia. Neulasta is administered as a single fixed dose per chemotherapy cycle.

NEUPOGEN(R) is indicated to decrease the incidence of infection, as manifested by febrile neutropenia, in patients with non-myeloid malignancies receiving myelosuppressive anti-cancer drugs associated with a significant incidence of febrile neutropenia.

Febrile neutropenia is a serious and common complication of many cancer chemotherapies. Up to half of cancer chemotherapy patients develop severe neutropenia, and up to 40 percent of patients receiving certain types of chemotherapy, who do not receive a white blood cell booster, will experience neutropenia with fever. On average, less than 10 percent of cancer patients receive proactive protection from neutropenia and thousands undergo unplanned hospitalization for neutropenia and its complications each year.

US Oncology, Inc., headquartered in Houston, is a leading cancer-care services company. The company supports the cancer-care community by providing oncology pharmaceutical services, cancer center services, and cancer research services to community-based practices. US Oncology is affiliated with more than 850 physicians operating in over 450 locations, including 77 outpatient cancer centers, in 27 states.

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

This news release contains forward-looking statements that involve significant risks and uncertainties, including those discussed below and more fully described in the Securities and Exchange Commission reports filed by Amgen, including our most recent Form 10-K. Amgen conducts research in the biotechnology/pharmaceutical field where 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.

Furthermore, our research, testing, pricing, marketing and other operations are subject to extensive regulation by domestic and foreign government regulatory authorities. In addition, sales of our products are affected by reimbursement policies imposed by third party payers, including governments, private insurance plans and managed care providers. These government regulations and reimbursement policies may affect the development, usage and pricing of our products. In addition, while Amgen routinely obtains patents for our products and technology, the protection offered by Amgen patents and patent applications may be challenged, invalidated or circumvented by our competitors.

Because forward-looking statements involve risks and uncertainties, actual results may differ materially from current results expected by Amgen. Amgen is providing this information as of March 14, 2002 and expressly disclaims any duty to update information contained in this press release.

Editor's Notes: Clinical studies showed Aranesp(TM) to be generally well-tolerated. Serious adverse events were associated with increases in hemoglobin greater than approximately 1.0 g/dL during any two-week period in patients treated with Aranesp or Epoetin alfa in Aranesp clinical trials, including increased incidence of cardiac arrest, neurologic events (including seizures and stroke) and exacerbations of hypertension, congestive heart failure, vascular thrombosis / ischemia / infarction, acute myocardial infarction, and fluid overload/ edema were observed. There have been rare reports of potentially serious allergic reactions including skin rash and urticaria associated with Aranesp. The most commonly reported side effects in Aranesp trials were infection, hypertension, hypotension, myalgia, headache, and diarrhea. Some of the adverse events reported are typically associated with CRF, or recognized complications of dialysis, and may not necessarily be attributable to Aranesp therapy.

No important differences in adverse event rates between the Aranesp and Epoetin alfa treatment groups were observed in the controlled studies. Aranesp is contraindicated in patients with uncontrolled hypertension.

Clinical trials showed that Neulasta(TM) is safe and well-tolerated. The most common adverse event attributed to Neulasta therapy following combination chemotherapy in patients (n=465) with lymphoma and solid tumors was bone pain reported in 26 percent of patients. In most cases, bone pain was controlled with non-narcotic analgesics. The most serious adverse event attributed to Neulasta was low oxygen in the blood, reported in one patient. While not reported in patients receiving Neulasta, rare events of adult respiratory distress syndrome, splenic rupture, and sickle cell crisis have been reported in patients receiving the parent compound, NEUPOGEN(R).

In the phase 3 trial of NEUPOGEN(R) therapy following combination chemotherapy in patients (n = 207) with small cell lung cancer, bone pain was reported in 22 percent of patients. In most cases, bone pain was controlled with non-narcotic analgesics such as acetaminophen.

Full prescribing information for Aranesp(TM) is available at www.aranesp.com and for Neulasta(TM) at www.neulasta.com.

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