This excerpt taken from the ALXN 8-K filed Apr 30, 2008.
Anti-CD200 Monoclonal Antibody for Cancer
Alexion is developing its novel and proprietary anti-CD200 monoclonal antibody, which is designed to enhance the immune response to several types of malignant tumors. The FDA has authorized the Companys IND for the use of this antibody as a therapy for patients with chronic lymphocytic leukemia (CLL). Alexion expects to begin a clinical trial in patients with CLL during 2008.