AIM: To determine the survival outcomes of New Zealand patients with unresectable or metastatic melanoma treated with pembrolizumab or nivolumab.

METHODS: This is a national retrospective cohort study. Patients with advanced unresectable or metastatic melanoma who received publicly funded immune-checkpoint inhibitors (ICIs) from 2017 to 2019 were included. Individual patient data were extracted from national administrative databases. The primary endpoint was OS, and secondary endpoints included OS by age, duration of treatment, posttreatment survival, and 30-day mortality from last pharmaceutical claim.

RESULTS: Five hundred ninety-seven patients were included, with a median follow-up of 25 months. One-year OS was 72%, the 2-year OS estimate was 60%, and median OS not reached. Survival did not differ by dichotomized age (≥70 vs. <70 year old), hazard ratio (HR) .94 (95% confidence interval (CI): .72-1.22; p = .62). Median duration of treatment was 9.0 months (95% CI: 7.9-10.1). Median post-treatment survival for the subgroup who had ceased treatment was 12.0 months (95% CI: 9.0-14.0). For the sample as a whole, the estimated 30-day mortality from last pharmaceutical claim was 15.7%.