Cost-effectiveness analysis of abiraterone for metastatic, castrate-resistant prostate cancer following previous chemotherap

Abstract

Objective: To evaluate the cost-utility and the budget impact (BI) of abiraterone in patients with castration-resistant prostate cancer previously treated with docetaxel. Methods: A Markov model was constructed, with monthly cycles, under the perspective of the Brazilian Public Healthcare System (SUS), in a 5-year time horizon, and with a 5% discount rate. The effectiveness estimate was obtained from the pivotal clinical trial for abiraterone in this health condition. For utility data, international estimates were applied; while for costs, SUS reimbursement information were used. In the BI analysis, the target population was estimated with claims data from DATASUS. Results: Abiraterone resulted in a gain of 1.045 quality-adjusted life years (QALY) and 1.609 life years gained (LYG), while for placebo these values were 0.763 and 1.299, respectively. The total cost for the abiraterone strategy was BRL 83,295, and for placebo, BRL 2,895. The incremental cost-effectiveness ratio (ICER) was BRL 284,416 per QALY gained. None of the estimates from the sensitivity analysis was below BRL 100,000 per QALY. Even when six parameters were variated simultaneously in the range more favorable to abiraterone, the results were still elevated, with an ICER of BRL 98,330 per QALY. The BI was BRL 270 million in 5 years in the most conservative scenario (average time of the treatment of 7.4 months and 10% of the new cases/year). Conclusion: Abiraterone shows unfavorable cost-effective results for this clinical condition in Brazil, with an ICER above 9 times the per capita per QALY. Results were robust in sensitivity analysis.