| Abstract: |
Unlabeled monoclonal antibodies have become essential components of the therapeutic arsenal for cancer. Many unlabeled monoclonal antibodies, however, lack sufficient antitumor activity to provide meaningful responses. To increase their efficacy, antibodies can be used to deliver radioisotopes to target cells. To date, most studies in leukemia have used the β-emitters 131I, 90Y, and 188Re labeled to anti-CD33, anti-CD45, anti-CD66, and anti-CD25 antibodies. These radioimmunoconjugates can eliminate large burdens of leukemia and can be given safely in conjunction with standard preparative regimens prior to marrow or stem cell transplantation. Whether they can improve outcomes compared with conventional preparative regimens remains to be determined by randomized trials. α Emitters have promise in the treatment of small-volume disease. 213Bi-labeled anti-CD33 has antileukemic activity and can produce complete remissions following treatment with single-agent cytarabine in some patients with advanced AML. Further advances in radioimmunotherapy will require investigation of more potent isotopes such as 225Ac, new methods of isotope delivery such as pretargeting, treatment of patients with less advanced disease, and eventually randomized trials comparing radioimmunotherapy to more standard approaches. © 2004 Elsevier Inc. All rights reserved. |
