NCT05677490 2026-05-08mFOLFIRINOX Versus mFOLFOX With or Without Nivolumab for the Treatment of Advanced, Unresectable, or Metastatic HER2 Negative Esophageal, Gastroesophageal Junction, and Gastric AdenocarcinomaAlliance for Clinical Trials in OncologyPhase 3 Recruiting382 enrolled