Alemtuzumab (Campath-1H)

Monoclonal antibodies (MoAb) augment the host anti-tumor response by selectively targeting the malignant cells. MoAb can mediate anti-tumor effects through three major mechanisms including intrinsic cytotoxic activity, antibody-dependent cellular cytotoxicity (ADCC), and activation of complement-dependent cytolysis. Alemtuzumab is a humanized IgG1 MoAb that targets the glycosylated peptide cell surface antigen CD52 that is abundantly expressed (approximately 500,000 molecules/cell) on normal and malignant B- and T-cells, but not on hemat o poietic stem cells. It was approved by the US Food and Drug Administration (FDA) in 2001 for the treatment of refractory B-cell chronic lymphocytic leukemia (B-CLL).