Trastuzumab rezetecan (SHR-A1811) is a HER2-targeting antibody-drug conjugate (ADC). Trastuzumab rezetecan is composed of a humanized anti-HER2 antibody , a cleavable linker MC-Gly-Gly-Phe-Gly (HY-44246), and a topoisomerase I inhibitor payload Rezetecán (HY-147408). Trastuzumab rezetecan can be used for research in HER2-positive breast cancer[1].