Osteoporosis Drugs Like Fosamax May Increase Risk of Broken Bones in Some Women
Longterm Use of Popular Class of Osteoporosis Drugs May Have Opposite Effect For Some Women, Experts Say
By CHRISTINE ROMO and LARA SALAHI
Mar. 8, 2010—
Sandy Potter, 59 of Queens, New York, was jumping rope with neighborhood children when she felt her thigh bone snap.
"I went up in the air and I came straight down to the ground," Potter said. "The pain was excruciating."
Potter, who was diagnosed with osteoporosis at age 48, had been taking the popular osteoporosis drug Fosamax for eight years before breaking her femur.
Fosamax, one in a class of drugs called bisphosphonates, is supposed to make bones stronger, and for many woman it is safe and effective. But now there's mounting evidence that for some women, taking these medications for more than five years could cause spontaneous fractures.
"We are seeing people just walking, walking down the steps, patients who are doing low-energy exercise," said Dr. Kenneth Egol, professor of orthopedic surgery at New York University Medical Center. "Very unusual, the femur is one of the strongest bones in the body."
Egol said X-rays of some of his patients look more like injuries from car accidents than from an otherwise-minimal fall.
"Over the last 18 months we are seeing this more frequently," he said.
Sales of the popular drug increased when doctors began prescribing it, not only to women with osteoporosis, but to others who were osteopenic -- with reduced bone density that might lead to the disease. Now some doctors worry that staying on the drug for more than five years can cause some women's bones to become more brittle.
Weighing the Risks
This is not the first time that many doctors have reported an opposite effect for people taking the drug. Fosamax has already been linked to severe musculoskeletal pain, as well as a serious bone-related jaw disease called osteonecrosis.
Also, the Food and Drug Administration asked the manufacturer, Merck, in 2008 to add information about the report of femur fractures.
After 16 months, Merck added patients' reports of femur fractures to the list of possible side effects included in the drug's package insert.
"It took Merck an entire year to respond," said ABC News senior health and medical editor Dr. Richard Besser. In small print on the package insert listing possible side effects from the drug, he said, there are "just six words: 'low energy femoral shaft and subtrochanteric fractures.'"
The FDA has also never made an effort to inform the public or doctors across the country who prescribe biphosphonates of the possible side effect, said Besser.
Both the FDA and Merck declined ABC News' request for interviews. The FDA said it is looking into reports of fractures.
"Nothing is more important to Merck than the safety of its medicines," said a written statement from Merck to ABC News. "A causal association has not been established between long-term bishphosphonate use and subtrochanteric femoral fractures. In clinical studies, FOSAMAX (alendronate sodium) has not been associated with increased fracture risk at any skeletal site. The company currently has several ongoing epidemiological studies to further investigate the issue of subtrochanteric femoral fractures."
data should become available just as the drug becomes generic, what timing
Dr. Joseph Lane, Orthopedic Trauma Surgeon at the Hospital for Special Surgery in New York City, said, "The drug companies have to recognize when there is a problem, they have to be up front with the public. If there's a concern they have to voice it and at least give everybody a fair chance to look at this carefully."
How Much For How Long?
Many studies suggest an overall benefit from taking the medication for women who are at risk for osteoperosis. In fact, biphosphonates can help to prevent hip and spine fractures, which for many women may lead to death.
"Normally your bone is constantly being remade," said Dr. Joseph Lane, Chief of Metabolic Bone Disease at the Hospital for Special Surgery in New York City. "These patients don't remake their bone and they acquire damage, microdamage, the collagen gets altered and we need to rejuvenate the skeleton."
In 2008, biphosphonate sales exceeded $3.5 billion according to data from IMS Health. In 2009, over 37 million prescriptions were written for the osteoporosis medications.
While some physicians use bone density scans to help drive their decisions, doctors generally prescribe them to women who are at an increased risk for either osteoporosis or fractures from osteoporosis they already have. A new tool developed by the World Health Organization can determine risk of having fractures and can help doctors determine which women with osteoporosis should be treated with medications.
Although biphosphonate are generally recommended for postmenopausal women, research does not indicate how long women should be on the drug. Many doctors now recommend a five-year limit.
"When they are on it for five, six, seven or eight years they lost their ability to remodel and regenerate their skeleton," said Lane. "[A subset of women] are very vulnerable and they will then develop problems of brittle bone."
Additional time on the medication depends on doctor's orders, said Besser.
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