An Injection a Year May Keep Bone Loss at Bay

May 2, 2007 — -- When it came to her treatment for the bone-weakening condition osteoporosis, 69-year-old Diana Mahon of Pittsburgh took her pills diligently.

But it wasn't always easy. Mahon was taking drugs called bisphosphonates -- pills such as Fosamax, Actonel and Boniva, which are currently the preferred treatment options for osteoporosis.

The drugs worked, but they came with a laundry list of considerations.

The pills, taken either weekly or monthly, need to be ingested on an empty stomach while standing or sitting. Afterward, the patient must not lie down, eat, drink or take other medication for at least half an hour.

"The fact that you have to stand or sit for that time limit was inconvenient at times," Mahon said.

Plus, these drugs have potentially serious gastrointestinal side effects, such as ulcers, heartburn and other problems -- something that Mahon learned firsthand when her drugs sent her to the emergency room with swallowing difficulties.

However, Mahon and the 10 million others like her who have osteoporosis, may have a new, more convenient option to prevent fractures and further bone loss in the near future. And the therapy would require only a yearly visit to the doctor.

But these benefits may not come without a cost. The study found that a certain kind of abnormal heart rhythm called atrial fibrillation was more common in patients receiving the drug.

In the current issue of the New England Journal of Medicine, a study of more than 7,700 postmenopausal women found that a single 15-minute yearly intravenous infusion of zoledronic acid, also known as Zometa or Reclast, reduced spine fractures by 70 percent and hip fractures by 41 percent over a three-year period. These results are similar to those obtained from current osteoporosis drugs.

The new option may prove to be a godsend for patients who simply cannot tolerate taking the oral pills.

According to Dr. Steven Cummings, senior author of the study and emeritus professor of medicine and epidemiology at the University of California at San Francisco, only 30 percent of patients continue to take the oral medications for an entire year.

"Giving one infusion a year guarantees compliance, which, in turn, increases the effectiveness of treatment -- like an airbag instead of seat belts," Cummings said.

Dennis Black, professor of epidemiology and biostatistics at the University of California at San Francisco and lead author of the study, said that if the new treatment is approved, patients who are already on many medications, unable to take pills or stay upright, or have gastrointestinal problems would likely be targeted first.

Not Just for Women

According to the 2004 Report of the Surgeon General on Bone Health and Osteoporosis, half of women over 50 years old will break a bone due to osteoporosis in their lifetimes.

While osteoporosis is a condition that predominantly affects women, the condition hits men as well.

In total, osteoporosis and low bone mass are estimated to affect approximately 44 million Americans -- women and men -- aged 50 and older.

And according to the study's authors, the costs of medical care associated with osteoporosis are more than $18 million annually in the United States alone.

"Osteoporosis represents a major concern in public health," said Dr. Javad Parvizi, joint specialist and director of orthopedic research at the Rothman Institute at Thomas Jefferson University Hospital.

"This study provides an alternative route of treatment for a class of medications that has been found to be very helpful in osteoporosis care and may be able to effectively treat men and women who have struggled on oral therapy," added Dr. Susan Bukata, clinical director of the Center for Bone Health at the University of Rochester.

Bukata further emphasized that "this study is really important for men who do not have many choices for therapy."

Just as Effective

The data show and experts agree that yearly infusions of Reclast appear to be at least as effective as currently available osteoporosis treatments in preventing all osteoporotic fractures, not just hip and spine fractures.

Bukata said, "[Reclast's efficacy] certainly matches the standard set by the oral bisphosphonates and shows true fracture protection equivalent to these drugs."

She also touts the benefits of a treatment that provides yearlong protection.

"[Patients] are much more likely to comply when the dosing is tied into a [yearly] doctor's visit," she said, "especially if they have to do nothing in between visits except take their calcium and vitamin D."

Mahon, who was in the study, couldn't agree more.

"I think it's marvelous," said Mahon, who does not know yet if she was in the treatment [Reclast] or nontreatment [placebo] group. "The fact that you can take something and it can last a year is a great incentive to go get it done."

Experts are especially enthusiastic about its potential to treat those who, like Mahon, have had trouble with or cannot take oral bisphosphonates.

Possible Heart Side Effect

However, the study also found serious cases of atrial fibrillation to be more prevalent among the Reclast treatment group. Fifty patients in the treatment group experienced this potentially dangerous heart condition, compared with 20 patients in the placebo group.

This was an unexpected finding that Dr. Felicia Cosman, osteoporosis specialist at the Helen Hayes Hospital, said has never been observed in any of the previous clinical trials of this particular drug.

Experts say this particular side effect may be common to all bisphosphonates, but it's too early to tell.

Still, most experts such as Dr. C. Conrad Johnston Jr., distinguished professor of medicine at the Indiana University School of Medicine, say these drugs, including Reclast, are quite safe with relatively few side effects.

And there is evidence that Reclast may allow patients to avoid a rare but serious side effect associated with the use of bisphosphonates. This condition, called osteonecrosis of the jaw, can cause the jaw bone to die away, leading to pain and dysfunction.

For now, however, patients may have to wait. Dr. Juliet Compston, professor of bone medicine at the University of Cambridge in the United Kingdom and author of the accompanying editorial to the study, said, "I don't think it should change clinical practice [at this time]."

But, since Reclast would only need to be given once a year, experts are encouraged that many more people will get it and stick with it if it is approved.

"It is an important addition to our armamentarium to fight osteoporosis," Johnston said.