As a result, the National Comprehensive Cancer Network (NCCN) guidelines recommend trastuzumab and pertuzumab for the treatment of advanced biliary tract tumors with HER2 amplification [151].The bispecific antibody ZW25 has been granted breakthrough therapy status by the FDA for patients with biliary tract cancer who have previously received other treatments and exhibit HER2 gene amplification. This evidence concerns the gene ERBB2 and biliary tract cancer.