Study Results Demonstrate the Activity of Aranesp in Treating Anemia in Cancer Patients Not Receiving Chemotherapy

NEW ORLEANS--(BUSINESS WIRE)--June 6, 2004--Amgen Inc. (NASDAQ:AMGN), the world's largest biotechnology company, today announced final results from a multi-center study demonstrating that Aranesp(R) (darbepoetin alfa) used in treating anemia in cancer patients not undergoing chemotherapy, a condition known as anemia of cancer, may improve hemoglobin levels, reduce the need for transfusion and improve the extreme fatigue experienced by patients. The results were presented by the study's lead investigator, Veena Charu, M.D., Pacific Cancer Medical Center, Anaheim, Calif., at the 40th Annual American Society of Clinical Oncology (ASCO) meeting. (Abstract #8084)

Nearly 350,000 cancer patients in the U.S. suffer from anemia of cancer, with common symptoms including physical and mental fatigue. While anemia, an abnormally low level of oxygen-carrying red blood cells, is recognized as a common problem in cancer patients receiving chemotherapy, some patients suffer from anemia due to the cancer itself, unrelated to chemotherapy. Despite its prevalence, anemia of cancer has been under-recognized and under-treated.

"While oncologists are familiar with anemia related to chemotherapy, we are now beginning to fully realize the extent to which early diagnosis and treatment of anemia of cancer can benefit patients," said Dr. Charu. "In this study, Aranesp was shown to correct anemia of cancer and reduce the need for transfusions."

The analysis included 285 anemic cancer patients with a current diagnosis or history of nonmyeloid malignancy who had not received chemotherapy within four weeks before screening or during the study. Patients were randomized to receive Aranesp 3.0 mcg/kg every two weeks for 21 weeks (Aranesp group) or 12 weeks of observation followed by nine weeks of Aranesp every two weeks (control group). The primary endpoint of the study was the number of hospital days during weeks one through 12. Additional endpoints included the incidence of transfusion, change in hemoglobin and the change of Functional Assessment of Cancer Therapy-Fatigue Scale (Fact-F) scores from baseline.

After 12 weeks of treatment, hospitalization was comparable for treated and control patients. Throughout the study, patients treated with Aranesp also showed improvements in hemoglobin and fatigue and a reduction in transfusion requirements. Mean change in hemoglobin was 2.1 g/dL in patients in the Aranesp group compared to 0.1 g/dL in the control group. Patients also reported a significant reduction in fatigue with a mean Fact-F score change of 7.7 in the Aranesp group and 1.8 in the control group. During weeks one through 12, 12 percent of patients in the Aranesp group received a transfusion compared to 22 percent in the control group. Further studies are underway to confirm these findings.

The adverse event profile is consistent with what would be expected in this patient population.

About Aranesp

Aranesp was approved by the U.S. Food and Drug Administration (FDA) in July 2002 for the treatment of chemotherapy-induced anemia in patients with nonmyeloid malignancies. Aranesp was approved by the FDA in September 2001 for the treatment of anemia associated with chronic renal failure, also known as chronic kidney disease, for patients on dialysis and patients not on dialysis.

Aranesp is a recombinant erythropoietic protein (a protein that stimulates production of oxygen-carrying red blood cells). Amgen revolutionized anemia treatment with the discovery of recombinant erythropoietin, epoetin alfa, which is currently marketed in the U.S. by Amgen as EPOGEN(R)(1) and by Ortho Biotech Products, L.P., as Procrit(R)(2). Building on this heritage, Amgen developed Aranesp(R), which contains two additional sialic acid-containing carbohydrate chains than the epoetin alfa molecule resulting in more activity with the added benefit of less frequent administration.

Aranesp is contraindicated in patients with uncontrolled hypertension. Erythropoietic therapies may increase the risk of thrombotic and other serious events; dose reductions are recommended if the hemoglobin increase exceeds 1.0 g/dL in any two-week period. The most commonly reported side effects in Aranesp trials were fatigue, edema, nausea, vomiting, diarrhea, fever and dyspnea.

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 STATEMENT

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, 2003, 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 first 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 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 first party suppliers.

Aranesp prescribing information can be accessed by calling 800-772-6436 or by logging onto www.aranesp.com.

EDITOR'S NOTE: 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.

(1) EPOGEN(R) is a registered trademark of Amgen Inc. (2) Procrit(R) is a registered trademark of Ortho Biotech Products,

L.P.

CONTACT: Amgen, Thousand Oaks, Calif.
Kelly Stoddard, 805-447-4587 (media)
Investor Relations, 805-447-1060 (investors)
www.Amgen.com