In an open-label, Phase 1b/2 clinical trial at 43 sites in 12 countries (AG221-AML-005), 50 (74%) patients in the combination group of enasidenib plus azacitidine achieved an OR rate higher than that in 12 (36%) patients of the azacitidine monotherapy group, suggesting the improved outcome by this combination for the newly diagnosed AML patients with mutant IDH2 (64). The gene discussed is IDH2; the disease is acute myeloid leukemia.