Cost-effectiveness of osteoporosis treatments in postmenopausal women using FRAX™ thresholds for decision.

Purpose: FRAX™ is a fracture prediction algorithm to determine a patient's absolute fracture risk. There is a growing consensus that osteoporosis treatment should be based on individual 10-year fracture probability, as calculated in the FRAX™ algorithm, rather than on T-scores alone.

Objective: Our objective was to evaluate the cost-effectiveness of five years of branded alendronate therapy in postmenopausal French women with a known FRAX™ score.

Method: A Markov cohort state transition model using FRAX™ values and whenever possible population-specific data and probabilities. We estimated the incremental cost-effectiveness ratio (ICER) of alendronate versus no treatment in postmenopausal women with FRAX™ ranging from 10 to 3%.

Outcomes: Number of women to treat (NNT) for preventing hip fracture, costs, quality-adjusted life-years, incremental cost-effectiveness ratios.

Results: The incremental cost-effectiveness ratios (ICER) compared to no treatment at age 70 ranged from €104,183 to €413,473 per QALY when FRAX™ decreased from 10 to 3%. The NNTs for preventing one hip fracture ranged from 97 to 388 according to age (50-80 years) and FRAX™. Sensitivity analyses showed that the main determinants of cost-effectiveness were adherence to therapy and cost of treatment.

Conclusion: Using French costs of branded drug and current estimates of treatment efficacy, alendronate therapy for 70-year-old women with 10-year probability of hip fracture of 10% just meets the accepted cost-effectiveness threshold. Improving treatment adherence and/or decreasing treatment cost lowers the ICER. The model however underestimates the potential benefit by excluding other fractures.