OBJECTIVES: To assess cost-effectiveness of pembrolizumab monotherapy for first line treatment of locally advanced non-small cell lung cancer (NSCLC) expressing any level of programmed death ligand-1 (PD-L1, Tumor Proportion Score [TPS] ≥1%) from a US payer perspective.

METHODS: A partitioned survival model with one-month cycles was developed, based on published overall survival (OS) and progression free survival (PFS) curves from the KEYNOTE-042 trial, to compare costs and effects of pembrolizumab monotherapy versus platinum-based chemotherapy doublets (standard of care, SOC). Survival probabilities were extended to a ten-year time horizon using standard parametric extrapolation methods. Costs were limited to direct medical care and treatment costs. Both costs and outcomes were discounted at 3%. One-way and probabilistic sensitivity analyses were conducted to explore uncertainty in the model.

RESULTS: In the base-case analysis comparing pembrolizumab monotherapy to standard of care chemotherapy, pembrolizumab resulted in an incremental gain of 0.76 life years and an incremental gain of 0.58 quality adjusted life years (QALY). The incremental cost-effectiveness ratio (ICER) was $145,460 per QALY gained. Probabilistic sensitivity analysis resulted in ICERs that fell below $150,000 per QALY 58% of the time.

CONCLUSIONS: The base-case analysis indicates that pembrolizumab monotherapy for first line treatment of locally advanced NSCLC is potentially cost-effective at a willingness-to-pay (WTP) threshold of $150,000 per QALY gained. Sensitivity analyses suggest that there is a high degree of uncertainty around the base case estimate which may warrant additional research.