The pivotal role of programmed death-ligand 1 (PD-L1) checkpoint inhibition for treating advanced melanoma has been confirmed in findings from the KEYNOTE-006 study comparing the anti-PD-L1 antibody pembrolizumab immunotherapy with the anti-cytotoxic T-lymphocyte associated protein 4 (CTLA-4) drug ipilimumab for treating patients with unresectable advanced or metastatic melanoma. Results from the study were reported at the European Society for Medical Oncology (ESMO) 2024 Annual Congress, held in Barcelona, Spain.