Cemiplimab Plus Chemotherapy Versus Chemotherapy Alone in Advanced NSCLC: 2-Year Follow-Up From the Phase 3 EMPOWER-Lung 3 Part 2 Trial

Introduction: EMPOWER-Lung 3 part 2 (NCT03409614), double-blind, placebo-controlled phase 3 study, investigated cemiplimab (antiprogrammed cell death protein 1) plus chemotherapy versus placebo plus chemotherapy in tients with advanced NSCLC without EGFR, ALK, or ROS1 aberrations, with either squamous or nonsquamous histol-ogy, irrespective of programmed death-ligand 1 levels. primary analysis, after 16.4 months of follow-up, cemipli-mab plus chemotherapy improved median overall survival (OS) versus chemotherapy alone (21.9 versus 13.0 hazard ratio [HR] = 0.71, 95% confidence interval [CI]: 0.53-0.93, p = 0.014). Here, we report protocol-specified final OS and 2-year follow-up results. Methods: Patients (N = 466) were randomized 2:1 receive histology-specific platinum-doublet chemotherapy, with 350 mg cemiplimab (n = 312) or placebo (n = 154) every 3 weeks for up to 108 weeks. Primary end point was OS; secondary end points included progression-free survival and objective response rates. Results: After 28.4 months of median follow-up, median OS was 21.1 months (95% CI: 15.9-23.5) for cemiplimab plus chemotherapy versus 12.9 months (95% CI: 10.6-15.7) for chemotherapy alone (HR = 0.65, 95% CI: 0.51-0.82, p = 0.0003); median progression-free survival was 8.2 months (95% CI: 6.4-9.0) versus 5.5 months (95% CI: 4.3-6.2) (HR = 0.55, 95% CI: 0.44-0.68, p < 0.0001), and objective response rates were 43.6% versus 22.1%, respectively. Safety was generally consistent with previously reported data. Incidence of treatment-emergent adverse events grade 3 or higher was 48.7% with cemiplimab chemotherapy and 32.7% with chemotherapy alone. Conclusions: At protocol-specified final OS analysis 28.4 months of follow-up, the EMPOWER-Lung 3 study continued to reveal benefit of cemiplimab plus chemo- therapy versus chemotherapy alone in patients advanced squamous or nonsquamous NSCLC, across grammed death-ligand 1 levels. (c) 2023 Published by Elsevier Inc. on behalf of International Association for the Study of Lung Cancer.