This is an open-label, randomized, multi-site, Phase II, interventional trial designed to evaluate the efficacy, tolerability, and safety of BNT111 + cemiplimab in 120 anti-PD1-refractory/relapsed patients with unresectable Stage III or IV melanoma.

The contributions of BNT111 and cemiplimab will be delineated in single-agent calibrator arms. Patients in single-agent calibrator arms, who experience disease progression under single-agent treatment, may be offered the addition of the other compound to the ongoing treatment after re-consent.