CLDN18 and gastric cancer: Furthermore, in the FAST study, a randomized phase II study of zolbetuximab (IMAB362) plus EOX versus EOX alone for first-line treatment of advanced CLDN18.2-positive GC and gastro-esophageal adenocarcinoma, CLDN18.2 positivity was defined as moderate (2+) or strong CLDN18 staining (3+) in at least 40% of the tumor cells.