Amgen Submits Biologics License Application for FDA Approval of Palifermin.

THOUSAND OAKS, Calif. -- Amgen Inc. (Nasdaq:AMGN), the world's largest biotechnology company, today announced submission of a Biologics License Application (BLA) with the U.S. Food and Drug Administration (FDA) for palifermin, a first-in-class investigational compound in development by Amgen for oral mucositis (mouth sores). The potential therapeutic indication is to reduce the incidence, duration and severity of oral mucositis in patients with hematologic malignancies undergoing high-dose chemotherapy, with or without irradiation, followed by a bone marrow transplant.

Approximately 11,000 Americans with hematologic malignancies, including non-Hodgkins lymphoma, Hodgkin's disease, leukemia and multiple myeloma, undergo bone marrow transplants each year.

The BLA was submitted under the FDA's Fast Track designation program, which is designed to expedite FDA review of an investigational therapy for an unmet medical need. If approved, palifermin will be the first therapy indicated to reduce the incidence, duration and severity of oral mucositis in bone marrow transplant patients.

"Palifermin is a first-in-class, innovative biologic that protects the epithelium of the mouth and gastrointestinal tract from damage caused by anti-cancer therapy," said Beth Seidenberg, M.D., chief medical officer and senior vice president of global development at Amgen. "The palifermin BLA filing is an important milestone for Amgen and our commitment to advance innovative molecules that address unmet need in grievous illnesses."

In patients with oral mucositis, the sensitive cells (mucosa) lining the mouth and digestive tract are damaged by the drugs or radiation used in cancer treatment. Severe mucositis is extremely painful (often requiring opioid-like analgesics), interferes with alimentation (process of providing nutrition), increases the chance of serious infection and can force hospitalization. In addition, painful mouth sores can make everyday activities like eating, swallowing, talking and sleeping difficult or impossible.

The BLA filing contains data from the Phase 3 pivotal study of palifermin which demonstrated that patients with hematologic malignancies undergoing high-dose chemotherapy, with or without irradiation, and bone marrow transplant support who received palifermin suffered less ulcerative oral mucositis (grades 2-4) compared to those receiving placebo (15.7 days vs. 8.4 days). In addition, palifermin helped protect patients from the most severe form of oral mucositis (grade 4) with 20 percent of palifermin-treated patients experiencing this painful and debilitating side effect, compared to 62 percent of placebo-treated patients.

Serious adverse events occurred at the same rate in patients who received palifermin or placebo (21 percent). The most frequently reported serious adverse events in both groups were fever, gastrointestinal and respiratory related.

Most adverse events were attributable to the underlying malignancy, cytotoxic chemotherapy, or total body irradiation and occurred at similar rates in patients who received palifermin or placebo. Other adverse events were consistent with the pharmacologic action of palifermin on skin and oral epithelium and included rash, pruritus (itching), erythema (redness), edema (swelling), mouth/tongue thickness or discoloration, and taste disorders. These events were mild to moderate in severity and were reversible.

About Palifermin

Palifermin (a recombinant human keratinocyte growth factor) is a first-in-class investigational compound in development by Amgen for mucositis throughout the gastrointestinal tract. Like endogenous keratinocyte growth factor, palifermin targets epithelial cells lining the mouth and gastrointestinal tract by binding to certain epithelial cell-surface receptors. This binding stimulates epithelial cell proliferation, differentiation and upregulation of cytoprotective mechanisms.

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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