OBJECTIVES: Despite the proven efficacy of pembrolizumab for persistent, recurrent, and metastatic cervical cancer, its cost-effectiveness in Japan is not necessarily clarified. This study aimed to evaluate its cost-effectiveness from the perspective of payers in Japan.

METHODS: A partitioned survival analysis model was developed to compare the cost and quality-adjusted life years (QALYs) of pembrolizumab versus placebo based on clinical data from the KEYNOTE-826 phase 3 randomized trial. Direct medical costs were considered in terms of the Japanese healthcare system. Cost parameters were estimated using JMDC claims database.The incremental cost-effectiveness ratio (ICER) was estimated. Sensitivity analysis (SA) was performed to assess parameter uncertainty.

RESULTS: For the intention-to-treat (ITT) patients, pembrolizumab was associated with an additional 0.855 quality-adjusted life-year (QALY) at an additional cost of JPY7,263,842. The ICER was JPY8,495,041/QALY. For patients with a programmed death-ligand 1 combined positive score (PD-L1 CPS) ≥ 1 and 10, the ICER was JPY8,337,288/QALY and JPY7,309,470/QALY, respectively. For the ITT patients, probabilistic sensitivity analysis resulted in probability of 100 % that pembrolizumab would be cost-effective when the ICER was at the threshold of 15 million/QALY. For patients with PD-L1 CPS of ≥1 and ≥10, the probability that pembrolizumab would be cost-effective was 99.1% and 100%, respectively.

CONCLUSIONS: Applying the 15 million yen/QALY threshold, pembrolizumab was cost-effective. Under Japan's public medical insurance system, pembrolizumab is preferable in terms of cost-effectiveness.