OBJECTIVES: To estimate the impact of introducing the PD-1/PD-L1 inhibitors class in oncology treatment on key health outcomes and to inform public health policy decisions about cancer care after reducing the uncertainty around new therapy options in immuno-oncology in South Korea.

METHODS: The model was developed to compare health outcomes obtained in a situation where both anti–PD‐1/PD‐L1s and standard of care (SOC) were available versus a situation with SOC alone. Partitioned survival model was utilized to estimate overall survival and progression-free survival for six major indications over 5 years. An exponential distribution was fitted to survival function of SOC. Outcomes of anti–PD‐1/PD‐L1s was estimated using the piecewise modelling approach utilizing Kaplan-Meier curve followed by a best fitting survival curve. Incident number of patients and market share of anti–PD‐1/PD‐L1s during 2020-2024 were projected using published literature, Korean market survey data, and timing of products’ reimbursement. Sensitivity analyses were performed to test uncertainty of input parameters.

RESULTS: Introduction of the anti–PD‐1/PD‐L1 class led to a gain of 22,001 life years (+31%), 19,073 quality adjusted life years (+38%), and 22,893 progression-free life years (+82%), and 3,610 adverse events avoided (-11%) compared to the current SOC. Most of the adverse events from anti–PD‐1/PD‐L1s were attributed to the combination therapy with cytotoxic chemotherapy (91%). In the scenario of accelerating reimbursement timeline of the anti–PD‐1/PD‐L1s by one year, the life years gained increased by 14% compared to the base case.

CONCLUSIONS: Treatment with anti–PD‐1/PD‐L1 is expected to bring marked survival benefits to cancer patients. This study demonstrated the potentially beneficial health impact of utilizing the anti–PD‐1/PD‐L1 class at a population level and could inform health policy decision makers about cancer care to ultimately enhance population health.