Cost-effectiveness of bisphosphonate therapies for women with postmenopausal osteoporosis: implications of improved persistence with less frequently administered oral bisphosphonates.

ABSTRACTObjective: Studies have shown that weekly bisphosphonate dosing results in improved persistence compared to daily dosing among patients with postmenopausal osteoporosis, yet more than 50% of patients discontinue therapy within a year. An oral, less frequent administration bisphosphonate provides an opportunity to improve persistence, a parameter not well modeled in previous cost-effectiveness analyses of osteoporosis therapies.Research design and methods: We developed a Markov model to estimate the effect of improved persistence on the cost-effectiveness of bisphosphonates among postmenopausal women with established osteoporosis (vertebral fracture and bone mineral density T-score ≤ –2.5) and an average age of 78 years. Fracture risks, clinical efficacy, mortality, resource use, costs, and utilities were obtained from the published literature. Persistence rates were derived primarily from a published clinical trial. Approximately 50% greater persistence with a monthly versus a weekly therapy was a...