FDA Seeks Added Info On Amgen Bone Drug, Delays Decision

Amgen Inc. (AMGN) received a complete response letter from the U.S. Food and Drug Administration, delaying the approval of osteoporosis treatment denosumab as the agency seeks more information.

It is unclear how long it will take for Amgen to meet the requests, but Roger Perlmutter, executive vice president of research and development, said in a statement that the company plans to respond to the requests in the "near term."

Amgen shares traded down 2.5% to $59.80 in pre-market trading. Many on Wall Street had expected such a delay for the drug, which is key to Amgen's future growth, because regulators have a history of missing deadlines and may want more time to analyze the safety record of a new drug like denosumab.

Despite the delay, analyst generally expect the drug to ultimately be approved.

A spokeswoman declined to comment beyond a press release issued early Monday.

Amgen said the agency requested several items, including information on the company's submitted post-market surveillance plan.

The FDA isn't requiring any additional clinical trials prior to completing the review of the drug, but it did request a new clinical program to support approval for preventing postmenopausal osteoporosis. The FDA has also requested all updated safety data related to Prolia.

Denosumab has the support of six Phase III trials involving more than 11,000 patients, with a relatively clean safety profile. Since the approval submission earlier this year, data from two large studies of denosumab's usefulness in preventing complications from cancer's spread to bone have become available.

Amgen hasn't disclosed its regulatory filing plans for preventing cancer-related skeletal complications, but a third study is coming early next year and many expect approval in late 2010.

Amgen said the agency determined that denosumab needs a Risk Evaluation and Mitigation Strategy, which must include a medication guide, a communication plan, and a timetable for submission of assessments of the plans. Amgen has already submitted materials for such a program.

Denosumab is being reviewed for treating and preventing postmenopausal osteoporosis, and bone loss caused by hormone treatment in breast or prostate cancer. Amgen expects a separate FDA response for the cancer-related application.

-By Thomas Gryta; Dow Jones Newswires; 212-416-2169; [e-mail]