DOT1L inhibition as a monotherapy was investigated in a clinical study of patients with advanced hematological malignancies, including relapsed/refractory MLL-rearranged AML [189]; complete remission was seen only for two patients, and the most common adverse events were fatigue (39%), nausea (39%), constipation (35%) and febrile neutropenia (35%). This evidence concerns the gene KMT2A and acute myeloid leukemia.