Rapid preparation of short-lived alpha particle emitting radioimmunopharmaceuticals

Alpha emitting radionuclides are of considerable interest for targeted radioimmunotherapy. Generator supplied Bi-213 emitting 8.5 Mev alpha particles with a 45.6 min half-life has been conjugated to a monoclonal antibody (HuM 195-CHX-A-DTPA) for targeted therapy of leukemia in a clinical trial. The clinical dose preparation of pharmaceutical formulation by a pair of skilled radiochemists Look 25 min, which corresponds, to an overall decay loss of 30% of the initial Bi-213 activity eluted from the generator. In order to allow more widespread and practical clinical use of targeted Bi-213 alpha particle therapy, we developed a new procedure that is simpler, more rapid and adaptable to a hospital pharmacy. The new 10 min process includes a tandem elution and labeling, and an anion exchange column purification method that can be reproducibly used. (C) 2001 Elsevier Science Ltd. All rights reserved.