Osteoporosis drugs Fosamax, Actonel compared

NEW YORK (Reuters Health) - Postmenopausal women with the bone-thinning condition osteoporosis who are treated with alendronate (brand name, Fosamax) have greater gains in bone mineral density (BMD) than women treated with risedronate (Actonel), according to researchers.

Dr. Sydney Bonnick, of the Clinical Research Center of North Texas, Denton, and colleagues conducted a 1-year extension of the Fosamax Actonel Comparison Trial (FACT) to compare outcomes after 2 years of treatment.

Of the 1053 women who completed the first year, 833 women with low BMD were included in the extension study. The women continued on their assigned treatment -- either 70 milligrams of alendronate once weekly or 35 mg of risedronate once weekly -- for another year. The results are published in the Journal of Clinical Endocrinology and Metabolism.

While both drugs resulted in significant increases for all BMD measurements, alendronate-treated patients had significantly greater increases after 24 months.

Both treatments significantly reduced all biomarkers of bone turnover, but the differences between the groups favored alendronate, according to the investigators.

No significant differences were observed between the groups in terms of adverse events, including gastrointestinal upsets, Bonnick's team reports.

Source: Journal of Clinical Endocrinology and Metabolism, July 2006.