Denosumab and Zoledronate Cost-Effective for Osteoporosis in Chinese Postmenopausal Women at Specific FRAX Thresholds

Osteoporosis is a prevalent condition in postmenopausal women, significantly increasing the risk of debilitating fractures. Current treatment guidelines often rely on fracture risk assessment tools like FRAX® to guide intervention. However, the cost-effectiveness of various osteoporosis treatments can differ substantially across regions due to varying drug prices, healthcare costs, and willingness-to-pay thresholds. In China, there's a critical need to establish drug-specific, cost-effective FRAX® thresholds to optimize treatment initiation, ensuring both clinical benefit and economic sustainability for the healthcare system and patients.

Researchers employed a validated Markov microsimulation model to evaluate the lifetime costs and quality-adjusted life years (QALYs) for no treatment versus alendronate, zoledronate, denosumab, and teriparatide in Chinese postmenopausal women. Baseline patient characteristics and risk factor distribution were derived from China's largest national osteoporosis survey. The analysis adopted a societal perspective, using a willingness-to-pay threshold of USD 13,000 per QALY gained, which aligns with one times China's GDP per capita. The model simulated outcomes across various age groups and 10-year major osteoporotic fracture probabilities.

The microsimulation analysis revealed distinct cost-effectiveness thresholds for different osteoporosis treatments. Denosumab emerged as cost-effective at a 10-year major osteoporotic fracture probability of 7%. Zoledronate also reached cost-effectiveness, but at a higher 10-year major osteoporotic fracture probability of 12%. Notably, neither alendronate nor teriparatide achieved cost-effectiveness at any FRAX probability evaluated within the model. For denosumab, the cost-effective threshold for 10-year major osteoporotic fracture probability varied with age, ranging from 5% to 12%, increasing from 51 to 65 years and then declining in older women. For zoledronate, thresholds were 8% at 51-55 years, 12% at 71-75 years, and 8.5% at 76-80 years. This age-dependent variability highlights the nuanced economic considerations for treatment initiation.

Denosumab was the most cost-effective treatment, reaching favorable thresholds at a 10-year major osteoporotic fracture probability of 7%.