The use of radioimmunoconjugates in stem cell transplantation

Radiolabeled monoclonal antibodies have been used with encouraging results in conjunction with stem cell transplantation for patients with hematologic malignancies targeting a variety of surface antigens including CD33, CD45 and CD66 for leukemias, CD20 and CD22 for non-Hodgkin's lymphomas, and ferritin for Hodgkin's disease. The results obtained targeting epithelial antigens on solid tumors, however, have generally been less encouraging, primarily due to the relative insensitivity of these malignancies to ionizing radiation. In this report we review clinical studies that have incorporated myeloablative doses of targeted radiation using radiolabeled antibodies in conjunction with stem cell transplant regimens.