Patients with surgically resected stage III melanoma are at high risk for recurrence. The 5-year survival rate with ipulimumab was 11 percentage points higher than that with placebo (65% vs. 54%), but there were substantial immune-related toxic effects. Ipilimumab, a fully human monoclonal antibody that blocks cytotoxic T-lymphocyte antigen 4 (CTLA-4) to augment antitumor immune responses, was approved by the Food and Drug Administration (FDA) and the European Medicines Agency in 2011 at a dose of 3 mg per kilogram of body weight for the treatment of advanced melanoma. 1 , 2 On the basis of data from a phase 2 trial that indicated the potential for a dose of 10 mg per kilogram to have higher efficacy than the dose of 0.3 mg or 3 mg per kilogram in patients with advanced melanoma, although at a cost of more . . .