Experts Call for Changes After Bisphosphonate Drugs Linked to Femur Fractures in Osteoporosis Patients

Bisphosphonates include the drugs Aclasta, Actonel, Aredia, Bondronat, Boniva, Didronel, Fosamax, Fosavance, Reclast, Skelid, and Zometa

Sept. 14, 2010 - A widely prescribed class of drugs is highly effective in reducing common bone fractures in people with osteoporosis, but an expert panel announced today that these same drugs – when used long term – may be related to unusual but serious fractures of the thigh bone. Ten million people in U.S. have osteoporosis, mostly senior women. One out of two women and one in four men over 50 will break a bone due to osteoporosis.

In the most comprehensive scientific report to date on the thigh bone fractures, 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.

"For the vast majority of patients with osteoporosis, these drugs are an important weapon against fractures and their benefits far outweigh the risks of using them," said task force co-chair and lead author Elizabeth Shane, M.D., of Columbia University.

"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.

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.

The international, multi-disciplinary task force conducted an extensive review of both published and unpublished data and interviewed scientists at pharmaceutical companies that sell the drug and at the FDA, which maintains the MedWatch database that tracks reported side effects of approved medications.

The task force expressed concern about the lack of awareness of atypical femur fractures, their warning signs and their association with long-term use of bisphosphonates. More than half of patients with atypical femur fractures reported groin or thigh pain for a period of weeks or months before fractures occurred, according to the report.

More than a quarter of patients who experienced atypical femur fractures in one leg experienced a fracture in the other leg as well.

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.

"We know that bisphosphonates prevent many, many common fractures. For this reason, we want to emphasize that patients should not stop taking these drugs because they are afraid of the much more uncommon femur fractures," Shane said.  

”They should talk to their health professionals about their concerns and should let them know if they experience any new groin or thigh pain. Patients can also report any side effects of these medications to the FDA by phone or online”.

She added, "Health professionals should reserve bisphosphonates for patients with certain cancers, Paget's disease of bone, and patients with osteoporosis who are at high risk of having a fracture. Drug labels should include information about this side effect.

“Although the risks are very low, health professionals should know the warning signs of atypical femur fractures and regularly ask patients on these drugs about groin or thigh pain. They also should assess annually whether this therapy is appropriate for each patient.”

The task force report will be the topic of a session at the ASBMR 2010 Annual Meeting in Toronto on Saturday, October 16 and is available at www.jbmr.org.

About the Task Force

A full list of task force members and their affiliations is listed below. All task force members were required to disclose any potential conflicts of interest and their disclosures are published as part of the task force report. To ensure the objectivity of its findings, the task force included a physician and bioethicist with expertise in conflict issues affecting biomedical researchers and a scientist who does not work directly on osteoporosis or bisphosphonates or with pharmaceutical companies that make or market bisphosphonates. Additionally, the report underwent a rigorous peer review process prior to its acceptance for publication by the Journal of Bone and Mineral Research.

About ASBMR and the Journal of Bone and Mineral Research

The ASBMR is a professional, scientific and medical society that brings together clinical and experimental scientists involved in the study of bone and mineral metabolism. The Society has a hard-earned reputation for scientific integrity. The majority of the Society's revenue comes from membership dues, fees paid to attend the Society's annual meeting and subscriptions to ASBMR publications. Like many scientific, professional, and medical organizations, ASBMR also accepts grants from pharmaceutical companies, the federal government and other entities to support its mission. To ensure that the Society adheres to the highest ethical practices ASBMR has an ethics committee, consults with experts in health care ethics and reviews its practices with regard to managing potential conflicts of interest.

The Journal of Bone and Mineral Research is the leading source worldwide for cutting-edge basic and clinical research in the hormones that regulate bone and mineral metabolism and the treatment of bone and mineral disorders.

LIST OF TASK FORCE PARTICIPANTS

Elizabeth Shane, Task Force Co-Chair, Columbia University

David Burr, Task Force Co-Chair, Indiana University School of Medicine

Bo Abrahamsen, Copenhagen University Hospital Gentofte

Robert A. Adler, McGuire Veteran's Administration Medical Center

Thomas D. Brown (Reviewer Scientist), University of Iowa

Angela M. Cheung, University Health Network - University of Toronto

Felicia Cosman, Helen Hayes Hospital

Jeffrey R. Curtis, University of Alabama at Birmingham

Richard Dell, Kaiser Permanente Bellflower

David Dempster, Columbia University

Peter R. Ebeling, University of Melbourne

Thomas A. Einhorn, Boston Medical Center

Harry Genant, University of California at San Francisco

Piet Geusens, Maastricht University Medical Center, The Netherlands & University Hasselt, Belgium

Klaus Klaushofer, Hanusch Hospital – Ludwig Boltzmann Institute of Osteology

Kenneth Koval, Dartmouth-Hitchcock Medical Center

Joseph M. Lane, Hospital for Special Surgery

Fergus McKiernan, Marshfield Clinic

Ross McKinney (Ethicist), Duke

University School of Medicine

Alvin Ng, Singapore General Hospital

Jeri Nieves, Helen Hayes Hospital

Regis O'Keefe, University of Rochester Socrates Papapoulos, Leiden University Medical Center

Howe Tet Sen, Singapore General Hospital

Marjolein C.H. van der Meulen, Cornell University

Robert S. Weinstein, University of Arkansas for Medical Sciences

Michael Whyte, Shriners Hospital for Children