Mimpara -- Cinacalcet HCl -- Receives Positive Regulatory Opinion for Approval in Europe

THOUSAND OAKS, Calif.--(BUSINESS WIRE)--July 29, 2004--Amgen Inc. (Nasdaq:AMGN), the world's largest biotechnology company, today announced that the European Committee for Medicinal Products for Human Use (CHMP) has issued a positive opinion to approve marketing authorization for Mimpara(R) (cinacalcet HCl) in the European Union (EU) for the treatment of secondary hyperparathyroidism (HPT) in chronic kidney disease (CKD) patients on dialysis and the treatment of elevated calcium levels (hypercalcemia) in patients with parathyroid carcinoma. In the U.S., the drug is marketed as Sensipar(TM) and was approved by the Food and Drug Administration (FDA) following a priority review in March 2004. Mimpara is an innovative, oral calcimimetic, which directly lowers parathyroid hormone levels by increasing sensitivity of the calcium-sensing receptor to extracellular calcium.

"Amgen is proud to offer this innovative, first-in-class medicine to help meet a significant medical need for patients on dialysis and those with cancer of the parathyroid gland," said Beth Seidenberg, M.D., chief medical officer and senior vice president of global development at Amgen. "Once approved, Mimpara will be the only available therapy in the EU that allows physicians to safely and effectively reduce PTH while simultaneously lowering calcium-phosphorus product, calcium and phosphorus."

Mimpara is Amgen's first small molecule therapeutic and represents an important milestone for the company in the EU. It also represents a potentially significant advance for CKD patients on dialysis with secondary HPT, a metabolic disorder characterized by elevations in PTH, calcium and phosphorus levels, and for those with hypercalcemia due to parathyroid carcinoma, a rare, serious cancer of the parathyroid gland resulting in excess secretion of PTH.

Left untreated, patients with secondary HPT can suffer from bone disease, bone pain and fractures, soft tissue calcification, vascular calcification and cardiovascular complications. High calcium levels due to parathyroid carcinoma can lead to anxiety, depression, nausea, vomiting, bone fractures, kidney stones and in some cases coma.

Recommendations from the CHMP are typically endorsed by the European Commission for marketing authorization within three to four months.

About Mimpara

In clinical trials in patients with HPT on dialysis, Mimpara was safe and effective in reducing PTH, calcium-phosphorus product, calcium and phosphorus in a broad range of patients regardless of age, gender, race, years on dialysis or disease severity. Mimpara was effective both in patients receiving and not receiving vitamin D.

In a clinical trial in patients with hypercalcemia due to parathyroid carcinoma, Mimpara lowered calcium levels.

Based on its mechanism of action, Mimpara lowers calcium, so it should not be initiated if a patient's calcium level is less than 8.4 mg/dL. During dose titration, calcium levels should be monitored frequently and if levels decrease below the normal range, appropriate steps should be taken to increase calcium levels. The threshold for seizures may be lowered by reductions in calcium levels and, infrequently, seizures have been reported, primarily in patients with a seizure history. The most commonly reported side effects are nausea and vomiting.

Amgen licensed Mimpara from NPS Pharmaceuticals Inc. in 1996. In March 2004, the FDA approved cinacalcet HCl, which is marketed as Sensipar in the U.S. Amgen has also applied for regulatory approval in Australia, Canada and New Zealand.

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.

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    SOURCE: Amgen Inc.