Cost-effectiveness of olaparib, a PARP inhibitor, for patients with metastatic castration-resistant prostate cancer in China and United States.

Background: Metastatic prostate cancer is initially sensitive to androgen receptor inhibition, but eventually becomes metastatic castration-resistant prostate cancer (mCRPC). Olaparib has longer progression-free survival and better measures of response and patient-reported end points than either enzalutamide or abiraterone. In the present study, 2 Markov models were established to analyze the cost utility of olaparib in treating mCRPC from the perspectives of health services in China and the United States. Methods: Markov models were established to simulate the progress of mCRPC in China and the United States. The state transition probabilities and clinical data were extracted from the PROfound trial. The cost data were estimated from local pricing, the relevant literature and expert consultancy. The health outcomes are expressed by quality-adjusted life years (QALYs). All costs and incremental cost-effectiveness ratios (ICERs) are presented in US dollars. One-way deterministic sensitivity analysis and probabilistic sensitivity analysis were performed to assess the uncertainty of the models. Results: Based on the Chinese Markov model, the base case ICER for olaparib versus the control group was ¥392,727.87, with incremental costs of ¥93,673.23 and an incremental QALY of 0.23, indicating that it was not cost effective from the aspect of the Chinese healthcare system. However, as shown by the American Markov model, olaparib was dominant versus the control group, with a cost saving of $69,675.20 and a gain of 0.23 QALYs. One-way deterministic sensitivity analysis and probabilistic sensitivity analyses showed that the modeling results were not significantly affected by the model parameters. Conclusions: Olaparib treatment in patients with mCRPC is not cost effective in China, but it is cost saving in the United States.