From PharmGKB, the efficacy of the chemotherapy drug cyclophosphamide (often used for DLBCL treatment) and the clearance of cyclophosphamide and fludarabine was shown to be affected by the presence of a missense variant at chr19:41515263 (A>G) in the CYP2B6 gene in a study carried out in chronic lymphocytic leukemia (CLL) patients. This evidence concerns the gene CYP2B6 and B-cell chronic lymphocytic leukemia.