Automated production of [68Ga]Ga-DO3A-VS-Cys40-Exendin-4 for the Glucagonlike Peptide 1 Receptor imaging

1056 Objectives Glucagon-like peptide 1 receptor (GLP-1R) has been demonstrated to be an important cell surface marker for imaging of pancreatic islets and insulinoma. [68Ga]Ga-DO3A-VS-Cys40-Exendin-4 displayed very high specific binding to GLP-1R expressed on pancreatic islets in rodent and nonhuman primates and in one clinical case of insulinoma. The ability to automate the synthesis process for this probe, although challenging, is a prerequisite for clinical application. To our knowledge, we are the first to report an automated synthesis process of this probe that is reproducible and can be used in future clinical studies. Methods [68Ga]Ga-DO3A-VS-Cys40-Exendin-4 was synthesized using an Eckert \u0026 Ziegler Modular-Lab PharmTracer system starting with DO3A-VS-Cys40-Exendin-4 precursor (50 ug, 10.5 nmol) and 68Ga eluted from Eckert \u0026 Ziegler 68Ge/68Ga generator systems. The final product was purified by C-8 cartridge after the reaction in ammonium acetate buffer (pH = 4.6 ± 0.4) at 75 °C for 15 min. Results nbsp;[68Ga]Ga-DO3A-VS-Cys40-Exendin-4 synthesized by automation achieved ~70% radiochemical yield (RCY), \u003e 99% radiochemical purity (RCP), and high specific activity (\u003e 51 GBq/µmol) with total synthesis time of 30 min. We have demonstrated the ability to synthesize[68Ga]Ga-DO3A-VS-Cys40-Exendin-4 reproducibly using an automated synthesis systems that resulted in good RCY, high RCP and high specific activity that can be utilized in future clinical studies.\nResearch Support: This work was supported by the grant from Larry L. Hillblom Foundation (2015-D-007-SUP)