Drug Aids Bones, Study Finds
The osteoporosis drug Fosamax keeps strengthening bones, easing fears that the medicine might eventually boomerang and start making hips and spines brittle and prone to break, researchers said in a study released today.
The study is the longest test yet of Fosamax, which was approved in 1995. It has gained quickly in popularity as an alternative to hormone supplements, which have been linked in recent years to heart disease and cancer.
“This is a chronic condition and requires long-term treatment, so it’s really important to have the data,” said Dr. Henry Bone, the study’s lead author at St. John Medical Center in Detroit.
The results of the research, which was backed by the drug’s maker, Merck & Co. of Whitehouse Station, N.J., and collected by an international research team, were published today in The New England Journal of Medicine. The group, which included several researchers who disclosed that they had ties to Merck, had reported previously on the first several years of findings in the 10-year experiment. Reporting on the last five years, the researchers focused on 247 middle-aged and elderly women with postmenopausal osteoporosis.
The findings are likely to reassure doctors as well as patients who take Fosamax, known generically as alendronate.
About 8 million American women and 2 million men have osteoporosis. About 34 million others are at elevated risk. The disease is blamed for about 1.5 million broken bones a year, including many debilitating fractures of the hip and back.
The drug, which raked in $2.7 billion in worldwide sales last year, works by readjusting the continuous process of bone renewal. It slows bone-destroying cells and thus gives more time for bone-building cells to catch up. Doctors have wondered, though, whether the slower turnover might eventually do harm. Will bone finally begin to break as older, more calcified tissue becomes more predominant?
In this study, that did not appear to happen.
The number of fractures in the final five years was too small to be considered statistical proof. However, the raw numbers were seen as encouraging. Among women who took 10 milligrams of Fosamax daily, 5% suffered back fractures. Among women who stopped taking the drug during the last five years of testing, 6.6% had such breaks.
“The name of the game in osteoporosis treatment is fracture protection. That’s why this study is so interesting,” said Dr. Steven Harris, a bone specialist at UC San Francisco.
Bone density measurements were also heartening. The 10-milligram group gained almost 14% in bone density in the lower spines over a decade, including nearly 4% over the last five years. The group that stopped taking the drug boosted its bone density in the lower back by 9% over 10 years -- but nearly all of that took place during the first five years.
In the first group, hip bone also became denser, by almost 1%, over the last five years. The comparison group lost almost 2%.
Osteoporosis chiefly strikes women after menopause. Almost one in two women over 50 is expected to break a bone as a result of osteoporosis.
