Research Demonstrates Risedronate Increases Bone Mass In Post Menopausal Women

INDIANAPOLIS--Risedronate, a drug currently under development for the prevention and treatment of osteoporosis, significantly increases bone mass in post menopausal women, a new study indicates. The study results suggest that risedronate may help prevent the debilitating effects of osteoporosis.

The study appears in the February issue of the Journal of Clinical Endocrinology & Metabolism. The data was compiled from clinical trials at Indiana University School of Medicine and a Danish university.

Researchers at I.U. found that when they treated early post menopausal women with risedronate the women’s bone mineral density (BMD) increased, while a group of women treated with placebo actually lost bone. All of the women had normal bone mineral density at the beginning of the study.

“Osteoporosis is a serious and debilitating condition and thus prevention is just as critical as treatment,” said C. Conrad Johnston Jr., M.D., professor of medicine at IU. “This study indicated that early intervention with risedronate may be effective at preventing the bone loss that can lead to osteoporosis.”

The new study involved 111 post menopausal women who were randomized to one of three groups: the daily group, which received 5 mg of oral risedronate daily; the cyclic group, which received 5 mg of oral risedronate daily for the first half of every month followed by placebo for the remainder of the month; or the placebo group, which received daily oral placebo for the entire study period.

After two years, women in the daily and cyclic risedronate groups had increases in the amount of bone in their hip of 5.4 percent and 3.3 percent, respectively, while women in the placebo group experienced no increase. Women treated with placebo actually lost bone mass in the spine (an average loss of 4.3 percent), while those taking risedronate daily (the daily group) had an average increase of 1.4 percent.

When risedronate therapy was stopped at the end of two years, bone loss resumed in the treated groups, according to Dr. Johnston. But overall, levels of bone mass at the spine and hip of those treated with risedronate remained higher than that in the placebo group.

“This may indicate a persistent overall benefit of therapy,” Dr. Johnston said. “Based on the study results, risedronate could be an important new alternative for the prevention of early bone loss after menopause.”

Risedronate also appeared to be well tolerated by women in the study. There was no difference in the incidence of adverse events among the treatment and placebo groups.

Osteoporosis affects about 28 million Americans, most of them women. Post menopausal women are at especially high risk because their bodies no longer produce enough estrogen to maintain healthy bones. The loss of bone mass puts people at increased risk of fractures; in fact, osteoporosis is responsible for an estimated 1.5 million fractures annually in the United States.

Risedronate, to be marketed under the brand name Actonelâ by Procter & Gamble and Hoechst Marion Roussel if approved by regulatory authorities, is a new generation of drug called a pyridinyl bisphosphonate, a compound that works by preventing the breakdown of bone that results in osteoporosis and other bone disorders. It currently is in phase III trials for the prevention and treatment of osteoporosis, and is under review by the U.S. Food and Drug Administration for the treatment of Paget’s disease, another severe bone disorder.

In another recent study involving patients with Paget’s disease, daily treatment with risedronate significantly reduced bone pain, reduced the amount of disease activity, and was well tolerated in patients with progressive disease. Like osteoporosis, Paget’s disease increases the risk of fractures of crucial bones such as the hip, wrist and spine. It is caused by excessive breakdown of bone, followed by abnormal regrowth that leaves bones weak and can cause severe pain.

The results of this study were published in the January issue of the journal Bone.

Send to: I.U. School of Medicine
Office of Public & Media Relations

Contact: Mary Hardin
(AC) 317-274-7722
mhardin@iupui.edu

INDIANA UNIVERSITY
SCHOOL OF MEDICINE

MEDIA
RELATIONS

A STATEWIDE
RESOURCE

Phone
317 274 7722

Fax
317 278 8722