...efficacy in separate expansion cohorts, including HER2-high (IHC 3+ or 2+/FISH+) breast (BC), gastric/esophageal (GE)...33 pts have been treated in P1 and P2: 17 BC, 11 GE and 5 other cancers. HER2-high BC pts...ZW25 has been well tolerated with promising single agent anti-tumor activity in pts with heavily pretreated HER2-expressing cancers that have progressed after standard of care, including multiple HER2-targeted regimens.