Trastuzumab is a humanized IgG1 monoclonal antibody that selectively binds to HER2 with high affinity. Trastuzumab can be used for the research of HER2-positive metastatic breast cancer and gastric cancer[1][2][3]. (Note: The product specifications below only indicate the effective content of Trastuzumab. The component ratio of this product is Trastuzumab : excipients = 1:0.6-1:0.9.)