Amgen's denosumab gets mixed backing from US FDA panel

At a meeting on August 13, the US Food and Drug Administration's Reproductive Health Drugs Advisory Committee backed two of the three treatment indications that biotechnology giant Amgen is seeking for its new drug denosumab, but voted against all three prevention claims for the antibody.

News of the decision saw Amgen's shares rise 1.5% to $63.06, but close the day's trading barely changed. The drug, which will be commercialized under the trade name Prolia, has the potential to generate $2.6 billion in sales by 2012, according to analysts' estimates compiled by Bloomberg. The drug's sales will depend on how broadly the FDA believes it should be used for osteoporosis and cancer patients.

The panel voted 15-0 and 9-4 that denosumab had a favourable risk/benefit balance to treat bone loss in postmenopausal osteoporosis and to treat bone loss in patients undergoing hormone ablation therapy for prostate cancer, respectively.

However, it voted 13-2 against denosumab to treat bone loss in patients undergoing hormone ablation therapy for breast cancer. The panel felt there was insufficient evidence to support the prevention indications in osteoporosis, prostate cancer and breast cancer and voted against denosumab 12-3, 11-3, and 14-0, respectively.