First-Line Pembrolizumab + Chemotherapy Versus Placebo + Chemotherapy for Persistent, Recurrent, or Metastatic Cervical Cancer: Final Overall Survival Results of KEYNOTE-826

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. The phase III, double-blind KEYNOTE-826 trial of pembrolizumab 200 mg or placebo once every 3 weeks for up to 35 cycles plus platinum-based chemotherapy, with or without bevacizumab, showed statistically significant survival benefits with the addition of pembrolizumab for patients with persistent, recurrent, or metastatic cervical cancer (primary data cutoff: May 3, 2021). This article reports the protocol-specified final overall survival (OS) results tested in the PD-L1 combined positive score (CPS) ≥1, all-comer, and CPS ≥10 populations. At the final data cutoff (October 3, 2022), the median study follow-up duration was 39.1 months (range, 32.1-46.5 months). In the PD-L1 CPS ≥1 (N = 548), all-comer (N = 617), and CPS ≥10 (N = 317) populations, median OS with pembrolizumab–chemotherapy versus placebo–chemotherapy was 28.6 months versus 16.5 months (hazard ratio [HR] for death, 0.60 [95% CI, 0.49 to 0.74]), 26.4 months versus 16.8 months (HR, 0.63 [95% CI, 0.52 to 0.77]), and 29.6 months versus 17.4 months (HR, 0.58 [95% CI, 0.44 to 0.78]), respectively. The incidence of grade ≥3 adverse events was 82.4% with pembrolizumab–chemotherapy and 75.4% with placebo–chemotherapy. These results show that pembrolizumab plus chemotherapy, with or without bevacizumab, continued to provide clinically meaningful improvements in OS for patients with persistent, recurrent, or metastatic cervical cancer.