FAP6-19 is a fibroblast activation protein (FAP) targeting radioligand with a Kd of 18.2 nM. FAP6-19 selectively delivers therapeutic radioactive nuclides (such as 177Lu) to the tumor site by targeting the overexpressed FAP protein in the tumor microenvironment, achieving precise killing of cancer cells while minimizing radiation damage to healthy tissues. FAP6-19 exhibits extremely high total cellular uptake and good intracellular retention ability in HT1080 cells. After being labeled with 111In, FAP6-19 produced extremely high tumor/kidney and tumor/liver dose ratios in the mouse model with 4T1 tumors. FAP6-19 can be used in the research of solid tumors expressing FAP.
