EO-3021 is internalized in claudin 18.2-expressing cells as well as demonstrates cell killing across a range of cancer cell lines with low (IC50 = 228 ng/ml), medium (IC50 = 7 ng/ml), and high levels of claudin 18.2 (IC50 = 28 ng/ml) expression...EO-3021 demonstrates tumor regressions with a single dose across low, medium, and high claudin 18.2-expressing in vivo models derived from pancreatic (9 mg/kg), gastric (2 mg/kg), and lung cancers (8 mg/kg), respectively.