In the most comprehensive scientific report to date on the topic, the task force reviewed 310 cases of “atypical femur fractures,” and found that 94 percent (291) of patients had taken the drugs, most for more than five years. The task force members emphasized that atypical femur fractures represent less than one percent of hip and thigh fractures overall and therefore are very uncommon.
The task force was convened by the American Society of Bone and Mineral Research – the leading scientific organization on bone science – in the wake of growing concern about the connection between these drugs, called bisphosphonates, and unusual femur fractures.
The Food and Drug Administration (FDA) said in March that it would await the report before making recommendations about bisphosphonates and has received a copy of the task force’s report. The report was published in the Journal of Bone and Mineral Research.
The task force is calling for additional product labeling, better identification and tracking of patients experiencing these breaks, and more research to determine whether and how these drugs cause the serious but uncommon fractures, said David B. Burr, Ph.D., chair and professor of anatomy and cell biology at the Indiana University School of Medicine. He and Elizabeth Shane, M.D., of Columbia University, were the task force co-chairs.
Dr. Shane said that for the majority of patients with osteoporosis, the biphosphonates are an important part of their treatment and that their benefits far outweigh the risks of using them.
“Most of the patients who experienced these atypical femur fractures had been taking bisphosphonates for more than five years. However, we are concerned that there may be a relationship between these fractures and long-term bisphosphonate use and, although the risk is low, we want to make sure that people know about the warning signs,” she said.
Millions of people, primarily women, have been treated with bisphosphonates since they were approved in 1995. Bisphosphonates include the drugs Aclasta, Actonel, Aredia, Bondronat, Boniva, Didronel, Fosamax, Fosavance, Reclast, Skelid, and Zometa. Bone diseases, such as osteoporosis, drastically affect the way people function.
Individuals who suffer broken bones as a result of osteoporosis can suffer severe pain, loss of height and stooped posture that can affect breathing and digestion. One in five patients who walked before their hip fracture needs long-term care afterward. And although the rate of hip fractures is two to three times higher in women, after one year, the death rate in men is nearly twice as high.
Among the task force recommendations:
Product labeling should be changed to alert health professionals and patients to the possibility of atypical femur fractures for patients on bisphosphonate therapy and the associated warning signs; cases should be reported to the FDA MedWatch program.
New diagnostic and procedural codes should be developed for atypical femur fractures to improve the quality of case reporting and enable better review of medical records.
An international registry of patients experiencing atypical femur fractures should be established to track cases and facilitate future research.
The task force report will be the topic of a session at the ASBMR 2010 Annual Meeting in Toronto on Saturday, Oct. 16, and is available at www.jbmr.org.