“Every drug has side effects,” Dr. Shane said in an interview. “It may well be that this type of fracture is associated with bisphosphonates, but we don't yet know who is vulnerable and we need more information and more research in order to determine that.”
One of the goals of the task force convened by the American Society of Bone and Mineral Research will be to determine future research directions. The group, which began meeting last year, also is working to establish a case definition, review the literature, examine different imaging techniques, and consider the best management of patients with these fractures.
The task force expects to wrap up its work in the next few months, Dr. Shane said. Once completed, a report will be submitted to the Journal of Bone and Mineral Research and to the FDA. One action the task force is likely to recommend is the establishment of an international registry, allowing researchers to better study the rare fractures, she said.
To access the FDA statement, go to www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm203891.htm
A typical osteoporotic fracture (left) is contrasted with an atypical fracture in a patient after many years of bisphosphonate therapy.
Source Images courtesy Dr. Melvin Rosenwasser, Columbia University
My Take
Don't Lose Sight of Benefits
It's against the law to shout “fire” in a crowded theater (unless there really is a fire). Recent misleading reports in the lay press of cases of “atypical” femur fractures in patients taking Fosamax, and recent (non–peer reviewed) reports of orthopedic research suggesting a strong link between bisphosphonates and subtrochanteric femur fractures appear to be in that vein.
In a statement, the FDA said, “At this point, the data that FDA has reviewed have not shown a clear connection between bisphosphonate use and a risk of atypical subtrochanteric femur fractures.” We have reviewed the data (J. Clin. Endocrinol. Metab. 2010 Feb. 19 [doi:10.1210/jc.2009-1947]). Because of the small number of cases reported, it is unlikely that a sufficiently large series of such fractures could be assembled to begin to tease out risk factors.
Lost in the “smoke” is the serious problem caused by osteoporosis, the deaths and disability associated with fractures and the benefits of alendronate and similar drugs in reducing the risk of fractures. Life is about balancing benefits with risks. For the vast majority of patients with osteoporosis, the benefits of alendronate and other approved treatments for osteoporosis far outweigh the risks.
NELSON B. WATTS, M.D., is an endocrinologist and director of the University of Cincinnati's bone health and osteoporosis center. He disclosed that he has relationships with several pharmaceutical companies, including Amgen Inc., Procter & Gamble, Sanofi-Aventis, and Novartis Pharmaceuticals Corp., which manufactures the bisphosphonate Reclast (zoledronic acid).
