Data Show Aranesp(R) (Darbepoetin Alfa) Administered Once Monthly Maintains Hemoglobin Levels in Chronic Kidney Disease Patients with Anemia| Amgen

Data Show Aranesp(R) (Darbepoetin Alfa) Administered Once Monthly Maintains Hemoglobin Levels in Chronic Kidney Disease Patients with Anemia

Results Presented at the American Society of Nephrology 2005 Annual Meeting Add to the Growing Body of Evidence Examining Administration of Aranesp at Extended Dosing Intervals

PHILADELPHIA, Nov 12, 2005 (BUSINESS WIRE) -- Amgen (NASDAQ:AMGN), the world's largest biotechnology company, today announced results from a study by Silver et al. that indicates Aranesp(R) (darbepoetin alfa) administered once-monthly (QM) maintained stable hemoglobin control in chronic kidney disease (CKD) patients with anemia not receiving dialysis, who were previously receiving Aranesp dosed every other week (Q2W). Eighty-five percent of the patients who completed the study successfully maintained hemoglobin (Hb) levels of greater than or equal to 11g/dL (Poster #SA-PO940). The data were presented today at the American Society of Nephrology (ASN) annual meeting. Amgen expects to file new data with the U.S. Food and Drug Administration (FDA) on extended dosing regimens for Aranesp in CKD by the end of 2005.

"These results confirm previously published data that also show once-monthly Aranesp administration maintains stable hemoglobin control," said Marcia R. Silver, M.D., FACP, director, Hemodialysis Program Division of Nephrology and Hypertension, MetroHealth Medical Center, and associate professor of Medicine, Case Western Reserve University. "Administering Aranesp once-monthly provides patients, physicians and nurses with significant advantages, as it allows CKD-related anemia to be treated more conveniently with fewer office visits."

This 33-week study enrolled 152 patients who had Hb levels 11 to 13 g/dL and estimated glomerular filtration rate (eGFR) greater than or equal to 15 mL/min and less than or equal to 60 mL/min, were iron replete and were receiving stable doses of Aranesp Q2W. Upon enrollment, the frequency of Aranesp administration was extended to once-monthly. The initial Aranesp once-monthly dose was equivalent to the individual subject's total dose in the month preceding enrollment. Doses were then titrated to maintain Hb levels within a 11 to 13 g/dL range.

"Amgen has a strong history of developing innovative therapies for the treatment of anemia," said Will Dere, M.D., senior vice president of Global Development and chief medical officer at Amgen. "We continue to pursue ways to improve the lives of CKD patients, and exploring extended dosing intervals of Aranesp, such as once-monthly, is a powerful example of our commitment to these patients."

Most adverse events (AEs) were mild to moderate in severity and no patients reported treatment-related serious and life-threatening AEs. The most common AEs were back pain, peripheral edema and nasopharyngitis (seven percent of subjects for each event), which are consistent with previous studies.

Anemia and Chronic Kidney Disease (CKD)

According to the National Kidney Foundation, CKD affects 20 million Americans (one in nine adults) and more than 20 million others are at increased risk for developing kidney disease. CKD is an irreversible condition characterized by kidney damage and impaired function that often progresses over time. Patients with CKD often suffer from serious complications such as anemia, which occurs when failing kidneys no longer produce sufficient erythropoietin, a hormone that stimulates the production of oxygen-carrying red blood cells (RBCs). RBCs contain hemoglobin, a red, iron-rich protein that carries oxygen from the lungs to all of the body's tissues. Oxygen provides the energy the body needs for normal activities. Anemia occurs when the number of RBCs (or the Hb in them) falls below normal (12 to 18 grams/deciliter of blood). Therefore, the body gets less oxygen and does not have enough energy to function properly.

About Aranesp(R) (darbepoetin alfa)

Aranesp is a recombinant erythropoietic protein (a protein that stimulates production of oxygen-carrying red blood cells). Amgen revolutionized anemia treatment with the development of a recombinant human erythropoietin, epoetin alfa, which is currently marketed in the U.S. by Amgen as EPOGEN(R) (Epoetin alfa)(i) and by Ortho Biotech Products, LP, as Procrit(R) (Epoetin alfa)(ii). Building on this heritage, Amgen developed Aranesp, which contains two additional sialic acid-containing carbohydrate chains than the Epoetin alfa molecule, resulting in more activity. Like all other protein-based erythopoiesis stimulating agents (ESAs), including endogenous erythropoietin, Aranesp stimulates erythropoesis through the epoetin (EPO) receptor.

Aranesp was approved by the FDA in September 2001 for the treatment of anemia associated with chronic renal failure, also known as CKD, for patients on dialysis and patients not on dialysis. In July 2002, Aranesp was approved by the FDA for the treatment of chemotherapy-induced anemia in patients with nonmyeloid malignancies. Aranesp has been effectively used in over 500,000 anemic patients since its launch in 2002 and has an established safety profile.

Aranesp is contraindicated in patients with uncontrolled hypertension and patients with known hypersensitivity to the active substance or any of the excipients. 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. Pure red cell aplasia (PRCA) has been observed in patients treated with recombinant erythropoietins. Aranesp should be discontinued in any patient with evidence of PRCA and the patient evaluated for the presence of antibodies to erythropoietic products. The most commonly reported side effects in Aranesp trials were fatigue, edema, nausea, vomiting, diarrhea, fever and dyspnea. Aranesp dosage should be adjusted for each patient to achieve and maintain a target hemoglobin level not to exceed 12 g/dL. Doses must be individualized to ensure that hemoglobin is maintained at an appropriate level for each patient.

About Amgen

Amgen discovers, develops and delivers innovative human therapeutics. A biotechnology pioneer since 1980, Amgen was one of the first companies to realize the new science's promise by bringing safe and effective medicines from lab, to manufacturing plant, to patient. Amgen therapeutics have changed the practice of medicine, helping millions of people around the world in the fight against cancer, kidney disease, rheumatoid arthritis and other serious illnesses. With a broad and deep pipeline of potential new medicines, Amgen remains committed to advancing science to dramatically improve people's lives. To learn more about our pioneering science and our vital medicines, visit

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(i) EPOGEN(R) is a registered trademark of Amgen, Inc.

(ii) Procrit(R) is a registered trademark of Ortho Biotech Products, LP


Amgen, Thousand Oaks Christine Cassiano, 805-447-4587 (media) Tony Gringeri, 805-447-1060 (investors)