Cost-effectiveness of romosozumab for the treatment of postmenopausal women with osteoporosis at high risk of fracture in Belgium

This study evaluated the cost-effectiveness of sequential treatment with romosozumab-to-alendronate compared to alendronate monotherapy and teriparatide-to-alendronate, in postmenopausal osteoporotic women from a Belgian healthcare perspective. Romosozumab-to-alendronate was found to be cost-effective compared to alendronate monotherapy and dominant compared to teriparatide-to-alendronate for osteoporotic women at high risk of fracture in Belgium. Purpose This study aimed to evaluate the cost-effectiveness of sequential treatment with romosozumab followed by alendronate compared to alendronate monotherapy and teriparatide followed by alendronate, in postmenopausal osteoporotic women at high risk of fracture, from a Belgian healthcare perspective. Romosozumab is reimbursed in Belgium since December 2021. Methods A Markov microsimulation model was used to evaluate the cost-effectiveness of romosozumab-to-alendronate compared to alendronate monotherapy and to teriparatide-to-alendronate over a lifetime horizon. Patients transition between five different health states every 6 months based on fracture risks or death. The model was populated with Belgium-specific epidemiological and cost data, where available. The fracture risk reduction of romosozumab treatment was collated from the ARCH study, and from a published network meta-analysis. Costs were included from a healthcare perspective (NIHDI). Cost-effectiveness was reported in terms of costs per quality-adjusted life year (QALY), reported in Euro ((sic)) 2022. Deterministic (DSA) and probabilistic sensitivity analyses (PSA) were performed. Results Romosozumab-to-alendronate was associated with 0.12 additional QALYs at an additional cost of (sic)2314 compared to alendronate monotherapy, resulting in an ICER of (sic)19,978. Compared to teriparatide-to-alendronate, romosozumab-to-alendronate was found to be dominant, with higher QALYs and lower costs. The base-case results were robust to uncertainty in the input parameters when conducting the sensitivity analysis. Conclusion Sequential treatment with romosozumab followed by alendronate was found to be cost-effective compared to alendronate monotherapy and dominant compared to teriparatide followed by alendronate for postmenopausal women with osteoporosis at high risk of fracture in Belgium.