Cost-effectiveness analysis of first line pembrolizumab monotherapy for high programmed cell death ligand 1 expressed, advanced non-small cell lung cancer in Japan.

Background: Pembrolizumab monotherapy significantly extends progression-free and overall survival compared to platinum-based chemotherapy for advanced non-small cell lung cancer (NSCLC), but also has a significant impact on medical costs.

Aim: To clarify the health economic evidence for selecting the first-line treatment for patients with stage IV advanced NSCLC with a programmed cell death ligand 1 tumor proportion score of 50% or greater in Japan, we assessed the cost-effectiveness of pembrolizumab monotherapy compared with that of platinum-based chemotherapy.

Method: Using a Markov model, the study simulated three health states for patients, based on clinical data and utility values from KEYNOTE-024. Transition probabilities were estimated exponentially. Direct medical costs were calculated according to the 2022 National Health Insurance Medical Fee Points and Drug Price Standards. The outcomes measured included life years, quality-adjusted life years, and incremental cost-effectiveness ratio, with sensitivity analysis performed to evaluate the effect of uncertainties.

Results: Pembrolizumab led to an additional 1.58 life years and 1.23 quality-adjusted life years at an additional cost of 7,009,888 Japanese yen (48,448 U.S. dollars [USD]), resulting in incremental cost-effectiveness ratio of 4,436,638 Japanese yen (30,663 USD) per life year and 5,699,096 Japanese yen (39,388 USD) per quality-adjusted life year. Pembrolizumab was deemed cost-effective under a threshold of 7.5 million Japanese yen (51,835 USD) per quality-adjusted life year.

Conclusion: Pembrolizumab monotherapy is a cost-effective option for the first-line treatment of advanced NSCLC with high programmed cell death ligand 1 expression in Japan, providing valuable health economic evidence for treatment selection.