Pembrolizumab for Persistent, Recurrent, or Metastatic Cervical Cancer

BACKGROUND Pembrolizumab has efficacy in programmed death ligand 1 (PD-L1)–positive metastatic or unresectable cervical cancer that has progressed during chemotherapy. We assessed the relative benefit of adding pembrolizumab to chemotherapy with or without bevacizumab. METHODS In a double-blind, phase 3 trial, we randomly assigned patients with persistent, recurrent, or metastatic cervical cancer in a 1:1 ratio to receive pembrolizumab (200 mg) or placebo every 3 weeks for up to 35 cycles plus platinum-based chemotherapy and, per investigator discretion, bevacizumab. The dual primary end points were progression-free survival and overall survival, each tested sequentially in patients with a PD-L1 combined positive score of 1 or more, in the intention-to-treat population, and in patients with a PD-L1 combined positive score of 10 or more. The combined positive score is defined as the number of PD-L1–staining cells divided by the total number of viable tumor cells, multiplied by 100. All results are from the protocol-specified first interim analysis. RESULTS In 548 patients with a PD-L1 combined positive score of 1 or more, median progression-free survival was 10.4 months in the pembrolizumab group and 8.2 months in the placebo group (hazard ratio for disease progression or death, 0.62; 95% confidence interval [CI], 0.50 to 0.77; P<0.001). In 617 patients in the intention-to-treat population, progression-free survival was 10.4 months and 8.2 months, respectively (hazard ratio, 0.65; 95% CI, 0.53 to 0.79; P<0.001). In 317 patients with a PD-L1 combined positive score of 10 or more, progression-free survival was 10.4 months and 8.1 months, respectively (hazard ratio, 0.58; 95% CI, 0.44 to 0.77; P<0.001). Overall survival at 24 months was 53.0% in the pembrolizumab group and 41.7% in the placebo group (hazard ratio for death, 0.64; 95% CI, 0.50 to 0.81; P<0.001), 50.4% and 40.4% (hazard ratio, 0.67; 95% CI, 0.54 to 0.84; P<0.001), and 54.4% and 44.6% (hazard ratio, 0.61; 95% CI, 0.44 to 0.84; P=0.001), respectively. The most common grade 3 to 5 adverse events were anemia (30.3% in the pembrolizumab group and 26.9% in the placebo group) and neutropenia (12.4% and 9.7%, respectively). CONCLUSIONS Progression-free and overall survival were significantly longer with pembrolizumab than with placebo among patients with persistent, recurrent, or metastatic cervical cancer who were also receiving chemotherapy with or without bevacizumab.