Amgen’s Dmab Cuts Fracture Risk for Osteoporosis Patients, Just What Investors Wanted to See

Amgen finally has something emerging from its pipeline to thrill investors. The world’s largest biotech company, with research centers in Seattle and Cambridge, MA, is reporting today that its lead drug in development reduced the risk of spinal fractures for women with osteoporosis by a whopping 68 percent.

On another dismal day in the markets, this bit of news drove Amgen shares up 3.2 percent to $64.15 at 2:13 pm Eastern time. The climb came after researchers reported on results a study, called Freedom, of the experimental drug called denosumab, or dmab, for short. The trial, of 7,808 patients followed for three years, showed a 68 percent lower risk of spinal fractures for those who took dmab versus those on a placebo. It also lowered hip fracture risk by 40 percent, Amgen (NASDAQ: [[ticker:AMGN]]) said in a regulatory filing. The drug didn’t appear to cause increased rates of serious side effects, such as infection risk, heart disease, or tumor growth, researchers said. Findings were presented at the American Society of Bone and Mineral Research in Montreal.

“These are substantial, important reductions,” in fracture risk, said Steven Cummings, an osteoporosis researcher at the University of California, San Francisco, in a press conference hosted by Amgen.

Amgen, based in Thousand Oaks, CA, has been dogged for more than a year by studies showing risk of heart attack and death among patients taking its anemia drugs, Aranesp and Epogen, which accounted for more than 40 percent of its revenue last year. Investors have been waiting for something to change the subject, and this might be it, since the dmab news is pretty much exactly what Wall Street had in mind coming into the meeting.

Dmab “needs to produce at least a 70% reduction in vertebral fractures and a 30%-40% reduction in non-vertebral fractures in order to qualify as a bona fide blockbuster,” said Michael King, an analyst with Rodman & Renshaw in New York, in a note to clients this week, before the data were presented in Montreal. He added that adverse events like infections and malignancies can’t tilt too heavily against dmab, “or else the product’s risk/benefit profile will deteriorate quickly,” he said.

The drug, a genetically engineered antibody, is designed to work unlike any other treatment on the market for osteoporosis. It is meant to block the action of a protein called RANK Ligand, that activates signals that lead to the breakdown of bones, said E. Michael Lewiecki, director of the New Mexico Clinical Research & Osteoporosis Center, in the press conference.

Dmab is taken as an injection every six months, unlike a bisphosphonate drug like Merck’s Fosamax, which is taken as a once-weekly pill. If approved by the FDA, denosumab may generate $2 billion a year in sales, analysts say, equal to about 14 percent of Amgen’s 2007 revenue. The company is now working to put together an application to the FDA, which it hopes to file by year’s end, Amgen says.

Beyond the balance of safety and effectiveness, Cummings said the convenience of having a twice-yearly injection will help patients comply with their prescription guidelines, and lead to more patients getting therapy from primary care physicians. Most patients now take Fosamax or other drugs in its class that must be taken on a regular schedule. About half of patients have trouble sticking with the regimen, which means they lose the drug’s benefits, Lewiecki says. About 75 million people in the U.S., Europe, and Japan have osteoporosis, and the numbers are increasing as the population ages, Lewiecki says.

Investors now be keeping a close eye to see how many of those patients really will flock to dmab, assuming the FDA doesn’t find any fly in the ointment and allows the Amgen drug on the market.

“To the extent that patients can get reimbursement, I think patients will prefer this treatment because of its convenience,” Cummings says.

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.