Labelling of anti-epidermal growth factor monoclonal antibody with ~(177)Lu:radiochemical and biological evaluation

摘要

This study aims to evaluate the synthesis parameters of ~(177)Lu-anti-EGF-Mab using a macrocyclic ligand, DOTAM (2,2′,2″,2″-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl) tetraacetamide) and its in vivo biodistribution in animal models. DOTAM-EGF was synthesized in high yield at room temperature in 0.1M NaHCO_3 pH 8.2 using a mixture of DOTAM/anti-EGF-Mab in nonstoichiometric ratio. The complex was then labeled with ~(177)Lu (15mCi ~(177)LuCl_3, pH 4) with more than 95% labeling efficiency. Biodistribution evaluation revealed a major accumulation in periferal tumor tissues (up to 12.49% ID/g) at 24 h after i.v. injection while the tumor mass uptaked 7 times less activity. The liver, kidneys, and small intestine showed a moderate took up, the mean value was 3.4 ID/g in the first two hours post injection following a decreasing curve up to 0.5% ID/g at 72 h post injection. Based of the preliminary results of this study ~(177)Lu-(DOTAM)anti-EGF-Mab will be tested as a new radiopharmaceutical for epidermal malignancies.