Multinational phase 1 study of zanidatamab for advanced solid tumors with expression or amplification of HER2

HER2-targeted therapies have substantially improved outcomes for patients with HER2-positive breast and gastric or gastro-esophageal junction cancers. Several other cancers exhibit HER2 expression or amplification, suggesting that HER2-targeted agents can have broader therapeutic impact. Zanidatamab is a novel bispecific antibody directed against two non-overlapping domains of HER2. A multicenter phase 1 study evaluated zanidatamab for locally advanced or metastatic HER2-positive biliary tract cancer, colorectal cancer, or other types of solid cancer in patients who had received all available approved therapies. Zanidatamab was well tolerated. Confirmed objective response was seen in 37% of patients in the expansion phase.