111In-BD-PEG-anti-GRP

111In-BD-PEG-anti-GRP is a novel theragnostic radioligand targeting the gastrin-releasing peptide receptor (GRPR). Developed by researchers at Stanford University, the agent consists of an anti-GRPR antagonist ligand conjugated to a dual DOTA chelate via a "clickable" polyethylene glycol (PEG) linker, radiolabeled with the indium-111 (111In) isotope. In preclinical models of prostate cancer, 111In-BD-PEG-anti-GRP demonstrated high stability in mouse and human serum, strong binding to GRPR-expressing PC-3 cells, and high, receptor-specific tumor uptake with rapid renal clearance, enabling clear visualization of prostate tumors via SPECT/CT imaging.