Alendronate treatment for osteoporosis: a review of the evidence.

Alendronate, a bisphosphonate indicated for the management of osteoporosis, is an antiresorptive agent that directly inhibits osteoclast activity. It reduces bone turnover and increases spine and hip BMD. Equivalent effects on turnover and BMD have been reported with once-weekly dosing, using seven times the daily dose. Among 3658 women with osteoporosis enrolled in the Fracture Intervention Trial (FIT), there was a 53% reduction in hip fractures, a 48% reduction in morphometric vertebral fractures, a 45% reduction in clinical vertebral fractures, and a 30% reduction in all clinical fractures. Each of these differences was already statistically significant within 12 months of starting treatment. The drug is safe and well tolerated.