* Denosumab shown to reduce risk of bone complications
* Jaw problem seen in 22 patients vs. 12 Zometa patients
* FDA filing expected later this year
* Shares rise 2.7 percent (Adds company comment, analyst comment, background, byline)
By Deena Beasley
LOS ANGELES, Feb 8 (Reuters) - A third pivotal trial of Amgen Inc’s (AMGN.O) experimental drug denosumab found that it works better than a rival to delay and reduce the risk of fractures and other bone complications in men with advanced prostate cancer, the company said on Monday.
News of the results sent the company’s share up nearly 3 percent in after-hours trading.
Amgen said the 1,900-patient trial, which compared denosumab to Novartis AG’s NOVN.VX Zometa, met all of its primary and secondary goals.
The company said the results were statistically significant, but did not provide details — noting that full results would be announced at a medical meeting in June.
Amgen said overall adverse events, including infections, were generally similar between the two treatment groups.
Osteonecrosis of the jaw, death of jaw bone tissue, was seen in 22 patients receiving denosumab, compared with 12 patients receiving Zometa. In addition, the incidence of low blood calcium levels was more frequent in the denosumab arm, the company said.
Deutsche Bank analyst Mark Schoenebaum said the incidence of jaw necrosis in the three late-stage cancer trials has been about 1.8 percent for denosumab patients, compared with 1.3 percent for Zometa patients.
Amgen said both patient survival and the time to cancer progression were similar for both drugs in the prostate cancer trial.
The company said it plans to submit the results, along with results from the two earlier cancer patient trials, to U.S. regulators later this year.
“The consistency of the effect of denosumab is quite amazing — it is really very unusual to have three Phase 3 studies that yield such positive results,” said Roger Perlmutter, head of research and development at Amgen.
Credit Suisse has estimated that sales of denosumab could total $3 billion by 2013.
The drug, widely considered the most important growth driver in Amgen’s development pipeline, is still under review by the Food and Drug Administration as a treatment for osteoporosis after the agency asked in October for additional information from clinical trials.
The drug is the first in a new class designed to inhibit proteins that activate bone-destroying cells.
Shares of Amgen rose to $59 in extended trading from their $57.46 close. (Reporting by Deena Beasley; Editing by Tim Dobbyn; Editing by Gary Hill)