Nivolumab (Opdivo(®)) is a fully human monoclonal antibody against programmed death receptor-1, a negative regulatory checkpoint molecule with a role in immunosuppression. The drug is administered intravenously and is approved for the treatment of unresectable malignant melanoma in Japan. The potential for intravenous nivolumab to be used in the treatment of advanced malignancies such as melanoma was initially demonstrated in phase I dose-ranging trials. Subsequently, in a noncomparative, open-label, phase II trial, almost one-quarter of Japanese patients with previously treated stage III/IV melanoma (recurrent or unresectable) achieved a partial tumour response with intravenous nivolumab 2 mg/kg every 3 weeks. The clinical benefit of the drug was durable, with patients surviving free from progression for a median of 172 days and median overall survival not yet reached. Nivolumab had an acceptable tolerability profile in this trial, with fewer than 18 % of patients experiencing grade 3 or 4 adverse events related to the drug, the most common of which was increased γ-glutamyl transferase. Thus, nivolumab is an emerging, promising option for the treatment of malignant melanoma.