Trastuzumab is a humanized IgG1 monoclonal antibody that binds to subdomain IV of HER2 receptor with high affinity and specifcity, inhibiting ligand-independent HER2 signalling and proteolytic cleavage of its extracellular domain. It was the frst HER2-targeted therapy approved for the treatment of HER2-positive breast cancer.

Herceptin

[1] Heo YA, Syed YY. Subcutaneous Trastuzumab: A Review in HER2-Positive Breast Cancer. Target Oncol. 2019;14(6):749-758. doi:10.1007/s11523-019-00684-y