UPDATE 1-Amgen seeks additional U.S. denosumab approval

* Files for approval in advanced cancer patients

* Plans to seek EU approval soon

* Awaits July FDA decision on postmenopausal osteoporosis

NEW YORK, May 14 (Reuters) - Amgen Inc (AMGN.O) said it is seeking U.S. approval of its closely-watched osteoporosis drug denosumab for reduction of fractures and other skeletal related events in patients with advanced cancer, marking its second U.S. application for the experimental medicine.

The world's largest biotechnology company said on Friday that it submitted a Biologics License Application to the U.S. Food and Drug Administration based on data from three late stage clinical trials comparing denosumab to Novartis AG's(NOVN.VX) Zometa.

In addition to seeking U.S. approval, Amgen said it plans to soon submit marketing applications in the European Union, Switzerland, Canada, Australia, and Japan.

The FDA is due to decide by late July whether to approve denosumab as a treatment for postmenopausal osteoporosis.

The drug, which would be sold under the proposed brand name Prolia, is widely considered to be Amgen's most important future growth driver, and an additional cancer approval would translate into significantly higher sales.

"We believe that denosumab will offer substantial benefit to cancer patients suffering from bone metastases," Amgen's research chief Roger Perlmutter said in a statement.

"Denosumab, administered monthly as a 120 milligram dose subcutaneously, demonstrated consistently similar or greater efficacy in clinical trials when compared to zolendronic acid, offering the potential to improve on the current standard of care," added Perlmutter, using the chemical name for Zometa.

The company is expected to unveil Phase III data on denosumab in advanced cancer patients at a major cancer meeting next month.

Bone metastases, or the spread of tumors to the skeleton, occur in more than 1.5 million patients with cancer worldwide and are most commonly associated with cancers of the prostate, lung, and breast, Amgen said.

When cancer spreads to the bone, it can seriously damage or weaken the bone around the tumor, producing fractures, spinal cord compression, or the need to receive radiation or surgery, the company said.

Preventing such skeletal events could significantly reduce medical costs, Amgen said. (Reporting by Bill Berkrot; editing by Carol Bishopric)