Cemiplimab plus chemotherapy versus chemotherapy in advanced non-small cell lung cancer with PD-L1≥1%: 5‑year update of EMPOWER-Lung 3 results

Background: In EMPOWER-Lung 3 Part 2 (NCT03409614), a randomised, double-blind, placebo-controlled phase 3 study, cemiplimab+chemotherapy (chemo) showed significant improvements in overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) vs chemo and an acceptable safety profile in patients with squamous/non-squamous advanced non-small cell lung cancer (aNSCLC) irrespective of PD-L1 expression and without EGFR , ALK or ROS1 aberrations. Here we present the 5-year follow-up data for patients with PD-L1 expression≥1%. Methods: In EMPOWER-Lung 3, 466 patients were randomised 2:1 to receive 4 cycles of platinum-doublet chemo in combination with cemiplimab 350 mg (n=312) or with placebo (n=154) every 3 weeks up to 108 weeks. The primary endpoint was OS; secondary endpoints included PFS and ORR. This post hoc analysis focuses on patients with PD-L1≥1% with ~5-year follow-up (last patient last visit: 27 Feb 2025). P -values are nominal. Results: In 327 patients (70.2% of total study population) with PD-L1≥1%, median OS was significantly longer with cemiplimab+chemo than placebo+chemo (24.0 vs 12.1 months; HR: 0.54, P