Multinational phase 3 trial of perioperative pembrolizumab for early-stage non-small cell lung cancer: five-year outcomes from KEYNOTE-671

Primary analysis of the multinational phase 3 KEYNOTE-671 trial showed that adding perioperative pembrolizumab to neoadjuvant chemotherapy significantly improved survival outcomes compared with neoadjuvant chemotherapy and surgery alone in participants with early-stage non-small cell lung cancer (NSCLC). Five-year results from the study have now been published. Eligible participants with previously untreated, resectable stage II, IIIA, or IIIB (N2) NSCLC were randomized 1:1 to 4 cycles of pembrolizumab (n=397) or placebo (n=400) every three weeks, plus platinum doublet chemotherapy, followed by surgery and adjuvant pembrolizumab or placebo every three weeks for up to 13 cycles. Dual primary endpoints were investigator assessed event-free survival (EFS) and overall survival (OS). Median time from randomization to data cutoff was 60.4 months (range 42.6-85.8). The five-year EFS rate was 49.9% in the pembrolizumab arm versus 26.5% in the placebo arm (HR 0.58; 95% CI 0.48-0.69), while the five-year OS rate was 64.6% versus 53.6% (HR 0.74; 0.59-0.69). No detriment to health-related quality of life was observed in the pembrolizumab arm versus the placebo arm with longer follow-up. Safety was consistent with the known profiles of each treatment. The authors conclude that after five years of follow-up, addition of perioperative pembrolizumab to neoadjuvant chemotherapy resulted in improved survival outcomes.