ERBB2 and gastroesophageal junction adenocarcinoma: The superiority of combined chemotherapy plus zolbetuximab (an anti-claudin 18.2 monoclonal antibody) over chemotherapy plus placebo as first-line treatment was evaluated in patients with claudin 18.2-positive and HER2-negative patients with advanced or recurrent gastric or esophagogastric junction adenocarcinoma (SPOTLIGHT trial and GLOW trial; claudin 18.2 positivity was defined as ≥ 75% tumor cells showing strong-to-moderate staining intensity on IHC) [131, 161].