Definition

A radiotracer composed of SNA002, a targeting agent for programmed cell death-1 ligand 1 (PD-L1; cluster of differentiation 274; CD274), conjugated to the bifunctional, macrocyclic chelating agent 1,4,7-triazacyclononane-N,N’,N”-triacetic acid (NOTA), and radiolabeled with the radionuclide gallium Ga 68, with potential PD-L1 imaging activity using positron emission tomography (PET). Upon administration of gallium Ga 68-NOTA- SNA002, the SNA002 moiety targets and binds to PD-L1 expressed on certain tumor cells. Upon uptake and PET imaging, the radioisotope moiety can be visualized and the extent of PD-L1 expression can be assessed. SNA002 binds PD-L1 on a different epitope than most PD-L1 inhibitors.