Combination immune checkpoint blockade in advanced untreated gastroesophageal adenocarcinoma: Seeking biomarkers for durable benefit

The CheckMate 649 trial, recently published in Nature, established chemotherapy plus nivolumab as a standard in advanced, treatment-naive gastroesophageal adenocarcinoma, with best results seen in patients with high PD-L1 expression and microsatellite unstable tumors. In contrast, nivolumab plus ipilimumab, compared with chemotherapy, showed early progression and no overall survival benefit.