Janjigian YY, Shitara K, Moehler M, et al. - Via this multicentre, randomised, open-label, phase 3 trial (CheckMate 649), researchers assessed first-line programmed cell death (PD)-1 inhibitor-based therapies in gastric, gastro-oesophageal junction, and oesophageal adenocarcinoma. They present the first results for nivolumab plus chemotherapy vs chemotherapy alone. Adults (≥18 years) with previously untreated, unresectable, non-human epidermal growth factor receptor 2-positive gastric, gastro-oesophageal junction, or oesophageal adenocarcinoma, were included irrespective of PD-ligand 1 (PD-L1) expression. Participants were randomized (1:1:1 while all three groups were open) to nivolumab plus chemotherapy, nivolumab plus ipilimumab, or chemotherapy alone. Findings revealed that a superior overall survival, as well as progression-free survival advantage and an acceptable safety profile, was conferred for the first time by a PD-1 inhibitor i.e nivolumab in combination with chemotherapy, when compared with chemotherapy alone, in previously untreated patients with advanced gastric, gastro-oesophageal junction, or oesophageal adenocarcinoma. Nivolumab combined with chemotherapy affords a new standard first-line treatment for these cases.