Nivolumab (NIVO) + chemotherapy (chemo) vs chemo as first-line (1L) treatment for advanced gastric cancer/gastroesophageal junction cancer/esophageal adenocarcinoma (GC/GEJC/EAC): 5-year (y) follow-up results from CheckMate 649.
Authors: Yelena Y. Janjigian, Markus H. Moehler, Jaffer A. Ajani, Lin Shen, Marcelo Garrido, Carlos Gallardo, Lucjan Wyrwicz, Kensei Yamaguchi, James M. Cleary, Elena Elimova, Ricardo Elias Bruges, Michalis Karamouzis, Tomasz Skoczylas, Arinilda Bragagnoli, Tianshu Liu, Mustapha Tehfe, Stephen McCraith, Nan Hu, Jennifer Zhang, Kohei Shitara
Journal: Journal of Clinical Oncology (2025)

398 Background: At 4-y follow-up, 1L NIVO + chemo continued to demonstrate clinically meaningful overall survival (OS) and progression-free survival (PFS) benefit vs chemo with acceptable safety in patients (pts) with advanced non-HER2+ GC/GEJC/EAC from CheckMate 649. We report efficacy and safety results of NIVO + chemo vs chemo at 5-y follow-up. Methods: Adults with previously untreated, unresectable, advanced or metastatic, non-HER2+ GC/GEJC/EAC were enrolled, regardless of programmed death ligand 1 (PD-L1) expression. Pts were randomized to NIVO (360 mg Q3W or 240 mg Q2W) + chemo (XELOX Q3W or FOLFOX Q2W), NIVO + ipilimumab, or chemo. Primary endpoints for NIVO + chemo vs chemo were OS and PFS by blinded independent central review (BICR) in pts with PD-L1 combined positive score (CPS) ≥ 5. Results: Pts were randomized to NIVO + chemo (n = 789) or chemo (n = 792). NIVO + chemo continued to show OS and PFS benefit vs chemo in pts with PD-L1 CPS ≥ 5, pts with PD-L1 CPS ≥ 1, and all randomized pts at 60-month (mo) minimum follow-up (Table). OS rates at 60-mo were higher with NIVO + chemo vs chemo in pts with PD-L1 CPS ≥ 5, pts with PD-L1 CPS ≥ 1, and all randomized pts (Table), and OS benefit with NIVO + chemo continued to be observed in most prespecified subgroups. Objective response rates (ORRs) were higher and responses were more durable with NIVO + chemo vs chemo in pts with PD-L1 CPS ≥ 5, pts with PD-L1 CPS ≥ 1, and all randomized pts (Table). No new safety signals were identified. Conclusions: These results represent the first report of 5-y follow-up for anti–PD-1 + chemo combination therapy in GC/GEJC/EAC to our knowledge. NIVO + chemo continued to provide sustained long-term survival vs chemo with an acceptable safety profile after 5 y of follow-up. These data continue to support the use of NIVO + chemo as a standard 1L treatment for advanced GC/GEJC/EAC. Clinical trial information: NCT02872116 . Efficacy PD-L1 CPS ≥ 5 PD-L1 CPS ≥ 1 All randomized NIVO + chemo(n = 473) Chemo (n = 482) NIVO + chemo (n = 641) Chemo (n = 656) NIVO + chemo (n = 789) Chemo (n = 792) mOS (95% CI), mo 14.4 (13.1–16.2) 11.1 (10.1–12.1) 13.8 (12.4–14.8) 11.4 (10.7–12.3) 13.7 (12.4–14.5) 11.6 (10.9–12.5) HR (95% CI) 0.71 (0.61–0.81) 0.76 (0.67–0.85) 0.79 (0.71–0.88) 60-mo OS rate (95% CI), % 16 (12–19) 6 (4–9) 13 (11–16) 5 (4–7) 12 (10–14) 6 (4–8) mPFS a (95% CI), mo 8.3 (7.0–9.4) 6.1 (5.6–6.9) 7.5 (7.0–8.5) 6.9 (6.2–7.1) 7.8 (7.1–8.6) 6.9 (6.7–7.2) HR (95% CI) 0.71 (0.61–0.82) 0.77 (0.68–0.87) 0.79 (0.71–0.89) ORR a,b (95% CI), % 60 (55–65) 45 (40–50) 60 (55–64) 46 (42–51) 58 (54–62) 46 (42–50) mDOR a,c (95% CI), mo 9.6 (8.3–12.4) 7.0 (5.7–8.0) 8.6 (7.9–10.5) 6.9 (5.8–7.6) 8.5 (7.7–9.9) 6.9 (5.9–7.6) a Per BICR. b In pts with measurable target lesions at baseline. c In all measurable responders. DOR, duration of response; m, median.