The preliminary results from a phase II/III MAHOGANY trial (NCT04082364) evaluating margetuximab (an Fc-optimized mAb that binds HER2) plus tebotelimab (an IgG4κ bispecific molecule that binds PD-1 and LAG-3 concomitantly) with chemotherapy in first-line unresectable metastatic/locally advanced gastroesophageal junction adenocarcinoma (GEA) revealed potential synergic antitumor activity with good tolerability50. This evidence concerns the gene ERBB2 and gastroesophageal junction adenocarcinoma.