An overview of the results of clinical trials with alendronate, a promising treatment of osteoporosis in postmenopausal women.

The purpose of this overview is to provide a summary of recent data on the clinical safety and efficacy of alendronate sodium, an amino-bisphosphonate that is a potent and specific inhibitor of osteoclast mediated bone resorption, in the treatment of osteoporosis in postmenopausal women. Published data are available from two randomized, placebo-controlled, double-blind clinical trials of 2-year duration in over 470 patients with postmenopausal osteoporosis. The women studied were 4 to 5 years postmenopause, ages 42 to 76, with osteoporosis defined on the basis of low spine bone mineral density (BMD). Percent change in spine BMD was the primary endpoint; hip and total body BMD were secondary outcomes. In the Dose Ranging Study, alendronate 5 and 10 mg/day for 2 years significantly increased lumbar spine BMD by approximately 7.2%, which did not differ from patients receiving higher doses. Total hip BMD increased by 3.6 and 5.3%, respectively, with the 5 and 10 mg doses; 10 mg was significantly more effective than 5 mg. Placebo patients lost 1.2-1.4% BMD at these sites. Total body BMD also significantly increased with alendronate. In the Calcitonin Comparison Study, alendronate 10 and 20 mg/day for 2 years significantly increased spine and hip BMD; 100 IU of intranasal salmon calcitonin did not increase BMD at any site, and did not differ from placebo. Alendronate reduced bone turnover to a new steady state, as assessed by biochemical markers and was well tolerated. Preliminary reports indicate that alendronate progressively increases spine, hip, and total body bone mass for 3 years, with associated significant reductions in vertebral fractures, stature loss, and non-vertebral fractures.(ABSTRACT TRUNCATED AT 250 WORDS)