Definition

A radioconjugate composed of FAPI-74, a quinoline-based fibroblast activation protein (FAP)-targeted tracer belonging to the group of FAP inhibitors (FAPi) conjugated to the bifunctional, macrocyclic chelating agent 1,4,7-triazacyclononane-N,N’,N”-triacetic acid (NOTA) and labeled with the positron-emitting radioisotope fluorine F 18, with potential use as a tracer for FAP-expressing tumors and cancer-associated fibroblasts (CAFs) during positron emission tomography (PET). Upon administration of fluorine F 18 FAPI-74, the FAPI-74 moiety targets and binds to FAP-expressing tumor cells and FAP-expressing CAFs. Upon binding and internalization, FAP-expressing tumor cells and CAFs can be detected during PET imaging. FAP, a cell surface protein, is overexpressed in a variety of human cancer cell types and on CAFs in the tumor microenvironment (TME).