Gallium Ga 68-PNT6555

**Semantic type:** Pharmacologic Substance

**Definition:** A radioconjugate composed of PNT6555, a fibroblast activation protein (FAP)-targeting moiety linked to the macrocyclic chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), radiolabeled with gallium Ga 68 (68Ga), with potential use as a tracer for FAP-expressing cancer-associated fibroblasts (CAFs) and FAP-expressing tumor cells during positron emission tomography/computed tomography (PET/CT). Upon administration of gallium Ga 68-PNT6555, the FAP-targeting moiety targets and binds to FAP-expressing CAFs and tumor cells. Upon binding, FAP-expressing CAFs and tumor cells can be detected during PET/CT imaging. FAP, a cell surface protein, is overexpressed on CAFs in the tumor microenvironment (TME) and certain tumor cells.

**Synonyms:** - 68Ga-PNT6555 - [Ga-68]-PNT6555