Recently, Kim and colleagues demonstrated that the combination of enasidenib with all-trans retinoic acid (ATRA)–used to induce differentiation in promyelocytic leukemia (APL) cells [104]–has a synergistic effect on differentiation of a IDH2-mutated cell line and primary IDH2-mutated AML cells ex vivo [105]. The gene discussed is IDH2; the disease is acute promyelocytic leukemia.