OBJECTIVES: Melanoma is the malignancy with the highest increase in incidence in males and the second highest in females, in Greece. Adjuvant treatment with immune checkpoint inhibitors has significantly improved recurrence-free survival in patients with high-risk resectable melanoma. Pembrolizumab, a immune checkpoint inhibitor, is indicated in the adjuvant, and reimbursed in the metastatic setting for Melanoma in Greece. This study aims to assess the cost-effectiveness of pembrolizumab for resected stage IIB, IIC melanoma patients, in Greece.

METHODS: A markov cohort model with four health states (event-free, locoregional recurrence, distant metastasis, and death) was adapted from the Greek payer’s perspective, over a 40-year time horizon. Utility values and safety data applied in the model were extracted from the KEYNOTE-716 and KEYNOTE-054. The standard of care in stage II melanoma following complete resection is observation, hence this was used as a comparator in the model. Primary outcomes were quality-adjusted life-years (QALYs), total costs and incremental cost-effectiveness ratios (ICER)s per QALY gained. Both costs and outcomes were discounted at 3.0% per annum. Α Deterministic Sensitivity Analysis (DSA) was conducted to identify the input parameter’s impact on ICER and a probabilistic sensitivity analysis (PSA) to account for collective parameter’s uncertainty.

RESULTS: The total costs and outcomes of Pembrolizumab and observation were compared. The costs were estimated at € 129,006 and € 97,093, respectively. Pembrolizumab was more effective than observation with 10.91 and 9.79 LY’s ,which translated to 8.90 and 7.94 QALYs gained, respectively. The incremental analysis showed an ICER of €28,395 per LYG and €29,970 per QALY gained . The DSA indicated that the most influential parameters did not significantly change the analysis’ results. PSA confirmed the deterministic analysis results.

CONCLUSIONS: The present economic evaluation indicates that Pembrolizumab is a cost-effective therapeutic option (under the 52,770€/QALY threshold) compared to observation, in resected stage IIB, IIC melanoma in Greece.