Amgen says osteoporosis drug trial meets goals

LOS ANGELES (Reuters) - Amgen Inc said its experimental osteoporosis drug, denosumab, significantly reduced the risk of bone fracture in post-menopausal women in a large trial, triggering a rise of nearly 15 percent in its shares.

Denosumab, a bioengineered antibody that targets a protein involved with bone-destroying cells called osteoclasts, is seen as key to Amgen's future now that growth of its flagship anemia drug franchise has waned due to safety concerns.

Amgen said the 7,800 patient, three-year trial found that treatment with denosumab led to a statistically significant reduction in the incidence of new vertebral fractures, compared with treatment with a placebo.

The study also showed the drug reduced the incidence of new non-spinal and hip fractures, the company said.

Amgen said the incidence and types of side effects in the study, including serious infections and malignancies, were similar between the denosumab and placebo groups.

Some earlier trials of denosumab, which is also being developed as a treatment for bone loss in cancer patients, showed higher risk of infection with denosumab, leading to questions about whether the drug's safety profile will be sufficient for regulatory approval.

A spokeswoman for Amgen said full details of the trial would be presented at a medical meeting in mid-September.

Amgen shares were at $61.86 in after hours trading, up nearly 15 percent from the close at $53.92.

(Reporting by Deena Beasley, Editing by Toni Reinhold and Andre Grenon)