Adjuvant anti-PD-1 antibody treatment in stage III/IV melanoma: real-world experience and health economic considerations.

BACKGROUND: Anti-programmed death 1 (PD-1) antibodies have evolved as a new standard of care in the adjuvant treatment of completely resected melanoma. Real-world data on treatment efficacy and safety as well as cost-effectiveness are still limited. PATIENTS AND METHODS: Treatment outcomes were retrospectively analyzed in a continuous patient cohort receiving adjuvant nivolumab (91 patients) or pembrolizumab (9 patients). Based on the obtained clinical data, a semi-Markov model was developed to evaluate cost-effectiveness. RESULTS: After a median follow-up of 11.5 months, disease recurrence was observed in 39 patients (39 %). The site of first recurrence was locoregional in 17, distant in 19, and combined locoregional and distant in three patients. Twelve-month estimates for recurrence- and distant-metastasis-free survival were 64.8 % and 77.4 %, respectively. Sixteen patients experienced grade 3 or 4 treatment-related adverse events, while 22 patients discontinued treatment due to adverse events. The base-case Markov model yielded an incremental cost-effectiveness ratio of 13,330 € per quality-adjusted life year for adjuvant anti-PD-1 antibody treatment compared to a simulated observation cohort. CONCLUSIONS: Real-world outcomes of adjuvant anti-PD-1 antibody therapy in completely resected melanoma appear comparable to clinical trial data. Moreover, our data suggests this treatment strategy to be cost-effective according to Austrian health economic standards.