Denosumab: A cost-effective alternative for older men with osteoporosis from a Swedish payer perspective

Abstract

ObjectiveTo assess the cost-effectiveness of denosumab versus other treatments in men with osteoporosis who are ≥75years old from a payer perspective in Sweden. MethodsA lifetime cohort Markov model was developed with seven health states: well, hip fracture, vertebral fracture, other osteoporotic fracture, post-hip fracture, post-vertebral fracture, and dead. During each cycle, patients could have a fracture, remain healthy, remain in a post-fracture state or die. Background fracture risks, mortality rates, persistence rates, utilities, medical and drug costs were derived using published sources. Estimates of fracture efficacy were drawn from available studies in post-menopausal osteoporotic (PMO) women as BMD improvements have been shown to be similar across male osteoporosis (MOP) and PMO populations, and a recent clinical trial suggested that the fracture risk reduction from bisphosphonate therapy in men is similar to that seen in women in comparable studies. Lifetime expected costs and quality-adjusted life-years (QALYs) were estimated for denosumab, generic alendronate, generic risedronate, ibandronate, zoledronate, strontium ranelate and teriparatide. On average, patients in the model were 78years old, with bone mineral density T-score at the femoral neck of −2.12. Prevalent vertebral fractures were present in 23% of patients. In the base-case, the model assumed that patients would experience treatment-related effects up to 2years after discontinuation. Costs and QALYs were discounted at 3% annually. Extensive sensitivity analyses were conducted. ResultsTotal lifetime costs for denosumab, alendronate, strontium ranelate, zoledronate, risedronate, ibandronate and teriparatide were €31,004, €33,731, €34,788, €34,796, €34,826, €35,983 and €37,461, respectively. Total QALYs were 5.23, 5.15, 5.15, 5.17, 5.13, 5.12 and 5.22, respectively. Compared to other treatments, denosumab had the lowest costs and highest QALYs. In the one-way sensitivity analyses, when compared to alendronate (next least expensive strategy), the ICER for denosumab was most sensitive to the relative risk of hip fracture on denosumab. The probability of denosumab being cost-effective compared to the other treatments at a threshold of €66,000/QALY was 96.1%. ConclusionDenosumab dominated all comparators, including generic bisphosphonates, in the treatment of osteoporosis in men who were ≥75years old in Sweden.