Cost-effectiveness analysis of additional abiraterone for hormone-sensitive metastatic prostatic cancer treated with androgen deprivation therapy (ADT)

Abstract

Background: The recent LATITUDE trial showed that Abiraterone plus Prednisolone (AP) combined with androgen deprivation therapy (ADT) significantly improved overall survival of patients with hormone-sensitive metastatic prostatic cancer. We conducted a study aims to evaluate whether AP plus ADT is a cost-effective strategy from Hong Kong perspective. Methods: The current cost-effectiveness analysis (CEA) considered the reported efficacy of AP in the large-scale randomized clinical trial (LATITUDE) that recruited 1,917 patients of advanced prostate cancer, among which 1,002 had metastatic disease. Using a deterministic Markov model with probabilistic sensitivity analysis (PSA) for accounting parameter uncertainty, AP plus ADT was compared with ADT-alone in patients with metastases across a 20-year time horizon. Quality-adjusted life-year (QALY) and incremental cost-effectiveness ratio (ICER) were applied as the primary outcomes. The study took Hong Kong’s societal perspective and the WHO’s recommendation of 3 times the local gross domestic product (GDP) per capita (USD$43,530/HKD$339,531 in 2016) was used as the threshold of cost-effectiveness. Results: The ICER of adding AP on top of ADT was USD$183,003 (median, 95% central range [CR] USD$148,780-235,632; approximately HKD$1,427,425, CR HKD$1,160,480-1,837,926) per QALY gained. Referring to the WHO’s recommended cost-effective threshold, AP plus ADT was not a cost-effective strategy compared with the current ADT-alone standard care strategy. The combined strategy of AP plus ADT, however, would be cost-effective if the cost of AP were reduced to USD$3,116 (median, approximately HKD$24,304) per cycle, which is around 72% of its current price in Hong Kong public hospital. Conclusions: Despite the survival benefit and that Hong Kong is well-developed with high global ranking in GDP per capita, adding AP to ADT is not recommended as a cost-effective treatment in metastatic hormone sensitive prostatic cancer in Hong Kong setting.