Acute myeloid leukemia (AML) and high-risk myelodysplastic syndromes are genetically heterogeneous diseases associated with poor long-term survival.(1, 2) Despite most patients achieving a morphologic remission with frontline AML therapies, approximately 50% of patients still relapse.(3) For those without targetable IDH or FLT3 mutations, effective treatment options for R/R AML are limited, and long-term survival rates are dismal. The gene discussed is IDH2; the disease is acute myeloid leukemia.