Mechanisms of Alemtuzumab-Mediated Cytotoxicity in Hematologic Malignancies

Monoclonal antibodies offer a focused therapeutic approach for solid and hematologic malignancies. Alemtuzumab is a chimeric monoclonal antibody that targets the CD52 antigen on normal and malignant lymphoid cells and is approved for the treatment of patients with relapsed chronic lymphocytic leukemia. Its main mechanistic cell-killing effects include complement-dependent cytoxicity, antibody-dependent cell-mediated cytotoxicity, and apoptosis. Ongoing investigation into the relative importance of these cytotoxic pathways is necessary for improved understanding of the mechanisms of action by which alemtuzumab and other monoclonal antibodies exert their beneficial antitumor activity in vivo.