OBJECTIVES:

To assess the cost-effectiveness of pembrolizumab compared to platinum-based chemotherapy in previously untreated patients with metastatic non-small cell lung carcinoma (NSCLC) with strong positive programmed death 1 protein ligands (PD-L1 ≥ 50%) expression in Portugal.

METHODS:

A partitioned-survival model was parameterized using clinical data from a head-to-head phase III randomized clinical trial, KEYNOTE-024. A two-stage approach was used to adjust for crossover in the comparator arm. Utility was derived from KEYNOTE-024 using time-to-death weights. Portuguese-specific disease management resource use was estimated by a panel of clinical experts; resources were valued using national unit costs. The analysis was conducted from a societal perspective, assuming a life-time horizon and a 5% discount rate. Deterministic and probabilistic sensitivity analyses assessed the robustness of results.

RESULTS:

Pembrolizumab increases average life expectancy by 3.8 undiscounted life-years (LY) and 2.1 discounted LY. This allows an increase of 1.7 quality adjusted life-year (QALY). Economic analysis shows that higher costs of pembrolizumab arm are mainly due to longer treatment duration and patient survival. The estimated incremental cost-effectiveness ratios (ICER) are 51,944€/LY and 64,205€/QALY. Deterministic sensitivity analysis shows that results are robust to most scenarios, but sensitive to treatment duration and parametric extrapolation options. Probabilistic sensitivity analysis resulted in a median ICER of 64,248€/QALY.

CONCLUSIONS:

Considering usually accepted thresholds in oncology and the unmet need in metastatic NSCLC, the cost-effectiveness of pembrolizumab compared to chemotherapy regimen might be acceptable.