Pretargeted radioimmunotherapy (PRIT) using an antibody-streptavidin fusion protein in non-Hodgkin's lymphoma.

Pretargeted radioimmunotherapy (PRIT) decreases the amount of time that radioactivity non-selectively circulates. Our PRIT approach is a multi-step method in which a monoclonal antibody is used to target streptavidin to a tumor-associated antigen and biotin is then used to target 90Y to the streptavidin. A genetically engineered antibody streptavidin fusion construct was used to target tumor in a patient with non-Hodgkin's lymphoma. Impressive localization of 90Y to known and previously unknown areas of adenopathy was observed, thus demonstrating that a genetically engineered fusion protein can selectively target lymphoma cells as part of a clinically meaningful PRIT strategy.