Cost-effectiveness of romosozumab for the treatment of postmenopausal women at very high risk of fracture in Canada

SUMMARY: This study evaluated the cost-effectiveness of 1 year of romosozumab followed by alendronate versus oral bisphosphonates alone in women with postmenopausal osteoporosis at very high risk for fracture in Canada. Results showed that romosozumab sequenced to alendronate is a cost-effective treatment option, dominating both alendronate and risedronate alone. PURPOSE: To demonstrate the value of romosozumab sequenced to alendronate compared to alendronate or risedronate alone, for the treatment of osteoporosis in postmenopausal women with a history of osteoporotic fracture and who are at very high risk for future fracture in Canada. METHODS: A Markov model followed a hypothetical cohort of postmenopausal osteoporotic women at very high risk for future fractures, to estimate the cost-effectiveness of romosozumab and alendronate compared to oral bisphosphonates alone. A total treatment period of 5 years was assumed. Quality-adjusted life years and costs were estimated for each comparator across health states defined by different types of fragility fractures. RESULTS: Romosozumab/alendronate was associated with a lifetime gain of 0.103 and 0.127 QALYs and a cost reduction of $343 and $3805, relative to alendronate and risedronate, respectively. These results were driven by a reduction of the number of fractures (2561 per 1000 patients, versus 2700 for alendronate and 2724 for risedronate over lifetime). Romosozumab/alendronate had the highest probability of being cost-effective, relative to alendronate and risedronate, at any willingness to pay threshold value. CONCLUSION: Romosozumab/alendronate was associated with reduced costs and greater benefit relative to other comparators. Probabilistic, deterministic, and scenario analyses indicate that romosozumab/alendronate represents the best value for money; the uncertainty analyses are robust, and therefore romosozumab should be considered for reimbursement by public drug plans in Canada .