[177Lu]DOTA-anti-CD20: labeling and pre-clinical studies.

Anti-CD20 (Rituximab®), a specific chimeric monoclonal antibody used in CD20-positive Non-Hodgkin's Lymphoma, was conjugated to a bifunctional quelate (DOTA) and radiolabeled with (177)Lu through a simple method. [(177)Lu]-DOTA-anti-CD20 was obtained with a radiochemical purity higher than 97%, and showed good chemical and biological stability, maintaining its biospecificity to CD20 antigens. Monte Carlo simulation showed high doses deposited on a spheroid tumor mass model. This method seems to be an appropriate alternative for the production of [(177)Lu]-DOTA-anti-CD20 as therapeutic radiopharmaceutical.