NAMPT inhibition was also found to increase the efficacy of Tumor Necrosis Factor-Related Apoptosis Inducing Ligand (TRAIL), HDAC inhibitors, P-glycoprotein-1 (Pgp) inhibitors and of Rituximab, an anti-CD20 antibody, in leukemia cells [20–23]. The gene discussed is NAMPT; the disease is leukemia.