We have previously demonstrated preclinical efficacy for several TTCs binding to a variety of tumor antigens, including PSMA-TTC in prostate cancer [24,25]; CD33-TTC in acute myeloid leukemia [2]; CD70-TTC in kidney cancer [23]; FGFR2-TTC in colorectal, gastric and triple-negative breast cancer [11]; MSLN-TTC in breast, colorectal, lung, ovarian and pancreatic cancer [22,27,28]; and HER2-TTC in colorectal, breast, ovarian, gastric and lung cancer [26,29]. Here, FOLH1 is linked to triple-negative breast carcinoma.