In the 853 patients with PD-L1–positive tumors, the 3-year RFS rate was 65.3% (95% CI, 60.5% to 69.7%) in the pembrolizumab group and 46.4% (95% CI, 41.5% to 51.1%) in the placebo group (HR stratified by stage, 0.57; 99% CI, 0.43 to 0.74; P < .001; Fig 2B). Pembrolizumab was also consistently effective in the 116 patients with PD-L1–negative tumors, with the 3-year RFS rate being 56.9% (95% CI, 43.2% to 68.4%) in the pembrolizumab group and 33.3% (95% CI, 20.4% to 46.6%) in the placebo group. In resected high-risk stage III melanoma, pembrolizumab adjuvant therapy provided a sustained and clinically meaningful improvement in RFS at 3-year median follow-up. This improvement was consistent across subgroups.