preparation, evaluation and preliminary clinical utilization of 68 Ga-labeled NODAGA-coupled RGD peptide derivative

article i nfo Ge/ 68 Ga generator Introduction:The presentarticledemonstratesa 'mix-and-use'approachforradiolabelingRGD peptidederivative with 68 Ga,whichiseasilyadaptableinhospitalradiopharmacypractice.Theradiotracerthusformulatedwassuc- cessfully used for positron emission tomography (PET) imaging of breast cancer in human patients. Methods: The conditions for radiolabeling NODAGA-coupled dimeric cyclic RGD peptide derivative (NODAGA- (RGD)2) with 68 Ga were optimized using 68 Ga obtained from a 68 Ge/ 68 Ga generator developed in-house with CeO2-PAN composite sorbent as well as from a commercial 68 Ge/ 68 Ga generator obtained from ITG, Germany. Preclinical studies were carried out in C57BL/6 mice bearing melanoma tumors. The radiotracer was prepared in a hospital radiopharmacy using 68 Ga obtained from ITG generator and used for monitoring breast cancer pa- tients by positron emission tomography (PET) imaging. Results: 68 Ga-NODAGA-(RGD)2 could be prepared with high radiolabeling yield (N98%) and specific activity (~50 GBq/μmol) within 10 min at room temperature by mixing 68 Ga with the solution of the peptide conjugate.