Gallium Ga 68-NOTA-exendin-4

**Semantic type:** Pharmacologic Substance

**Definition:** A radiopharmaceutical composed of the glucagon-like peptide 1 receptor (GLP-1R) agonist exendin-4 linked by the macrocyclic chelating agent 1,4,7-triazacyclononane-N,N',N''-triacetic acid (NOTA) to the positron-emitting radionuclide gallium Ga 68, with potential imaging activity upon positron emission tomography (PET)/computed tomography (CT). Upon administration of gallium Ga 68-NOTA-exendin-4, the exendin-4 moiety binds to GLP-1R. The radionuclide moiety can be detected using PET/CT and GLP-1R-expressing tumors can be localized. GLP-1R, located on beta cells, is overexpressed on insulinomas, which are insulin-secreting neuroendocrine tumors.

**Synonyms:** - 68Ga-NOTA-exendin-4 - [68Ga]-NOTA-exendin-4