Currently, four ADCs have been approved by the FDA in 2013, including three ADCs, ado‐trastuzumab emtansine (T‐DM1, human epidermal growth factor receptor 2 [HER2]‐targeting),47 trastuzumab deruxtecan (T‐DXd, HER2‐targeting),48, 49 and sacituzumab govitecan (SG, trophoblast cell surface antigen 2 [Trop‐2]‐targeting) for breast cancer patients50 and enfortumab vedotin (EV, Nectin‐4‐targeting) for urothelial cancer patients.51 Here, TACSTD2 is linked to breast cancer.