ERBB2 and gastric cancer: There remains an unmet medical need in HER2-positive GC/GEJC, and a wide array of novel therapies and treatment regimens are currently under investigation in these patients; these include anti-HER2 monoclonal antibodies (margetuximab), checkpoint inhibitors (nivolumab and ipilimumab), tyrosine kinase inhibitors (tucatinib), and bispecific antibodies that target HER2 (zanidatamab) [18–22].