Next Tuesday, the struggling biotech releases data about denosumab, an experimental osteoporosis drug, and the data could make the difference between a multi-billion-dollar med and an also-ran in a crowded field. No small moment for a company that has staggered from setback to setback with its existing meds.
"Denosumab is a mega-blockbuster opportunity and will now emerge as the principal long-term value driver," Morgan Stanley analyst Steven Harr wrote in a recent research note, Reuters reports. "We see a high probability of regulatory success given data to date."
Two months ago, Amgen reported denosumab significantly reduced the risk of spine fracture in a three-year trial of 7,800 post-menopausal women, but never disclosed exactly how much the risk was reduced. That's what everyone is waiting to hear next week at the annual meeting of the American Society of Bone Mineral Research in Montreal. (Back story).
Investors will be looking to see how the twice-a-year injectable drug can fare in a $6 billion bisphosphonate market dominated by Merck's Fosamax, Sanofi-Aventis and Procter & Gamble's Actonel, Novartis' Reclast, Roche and Glaxo's Boniva.
Currently the most effective drug in reducing vertebral fracture risk over a three-year period is Reclast, known in Europe as Aclasta, which reduced the risk by 70 percent in clinical trials, and is the benchmark against which denosumab will be measured, Reuters notes.
"We view any comparable risk reduction of 65 percent to 70 percent or greater as a success for denosumab and believe it could eventually become the dominant treatment for osteoporosis," Joel Sendek, an analyst at Lazard Capital Markets, wrote in a research report.
A reduction in fracture risk of between 50 percent and 60 percent would place it roughly on a par with Fosamax, Boniva, and Lilly's Evista, which is a member of a different class of drugs known as selective estrogen-receptor modulators, Reuters notes. Any figure under 50 percent would be considered a serious disappointment, according to Sendek. Amgen stock has risen 18 percent since initial results were reported in July.
Amgen has said the most common side effects seen in the trial, known as FREEDOM, were mild joint and muscle aches. Investors will be closely watching to see whether there is any increase in the rate of infection in patients taking denosumab. An earlier trial showed an increase in the infection rate.
If the infection rate were not significantly higher than for the placebo, denosumab's safety profile could be significantly better than that of bisphosphonates, which bind to the bone and can stay in the body for years after treatment is stopped, Reuters writes.
Earlier this year, the FDA began reviewing hundreds of cases of patients taking bisphosphonates who reported severe and even incapacitating pain in muscles, joints and bones. The pain occurred days, months or years after starting the bisphosphonate. (Back story).
In addition, the agency said last year that it would study bisphosphonates after two reports in the New England Journal of Medicine found increased rates of serious atrial fibrillation in patients who took either Fosamax or Reclast.
A study published earlier this year in the Archives of Internal Medicine showed Fosamax was linked with an 86 percent higher risk of newly detected atrial fibrillation than patients who never used the drug. Merck has said it found no increased link in its clinical trials. Merck scientists were not immediately available to comment on the potential long-term side effects of Fosamax, which is now also available in generic form.
Amgen says denosumab does not stay in the body after treatment is stopped, meaning any side effects are more likely to be reversible. That is because unlike bisphosphonates, which bind to the bone, denosumab inhibits proteins that activate bone-destroying cells. When treatment is stopped, the drug leaves the body. That could give the drug a significant advantage over its rivals.
Roughly 10 million people in the United States and 200 million worldwide suffer from osteoporosis.