[New data on biphosphonate therapy: are therapeutic holidays advisable?]

Area of Science:

• Pharmacology
• Bone Biology
• Geriatric Medicine

Context:

• Bisphosphonates are effective osteoporosis treatments but long-term use raises concerns.
• Alendronate has a long skeletal half-life, suggesting potential for treatment cessation.
• The Fracture Intervention Trial Long-term Extension (FLEX) trial investigated alendronate discontinuation.

Purpose:

• To evaluate the effects of discontinuing alendronate on bone mineral density (BMD) and fracture rates.
• To inform clinical guidelines regarding the duration of bisphosphonate therapy.

Summary:

• Discontinuation of alendronate for up to 5 years after 5 years of treatment resulted in minimal loss of BMD.
• Vertebral and non-vertebral anti-fracture efficacy was maintained despite reduced BMD.
• The anti-resorptive effect slowly diminishes, particularly in the lumbar spine and femur.

Impact:

• Supports annual reevaluation of bisphosphonate therapy beyond 5 years.
• Highlights the need to consider individual patient factors like BMD, fracture history, and other medications.
• Caution against extrapolating alendronate findings to other bisphosphonates due to molecular differences.