CD200 and B-cell chronic lymphocytic leukemia: In a Phase I clinical trial (NCT00648739) sponsored by Alexion Pharmaceuticals, a group of investigators tested the efficacy, safety, pharmacodynamics, and pharmacokinetics of samalizumab, a recombinant humanized anti-CD200 monoclonal antibody, in treating tumors associated with CLL and multiple myeloma (MM) (79).