Felicitas Thol, MD, from Hannover Medical School, Hannover, Germany, discusses how targeted treatments for IDH1 and IDH2 mutations work in acute myeloid leukemia (AML) at the International Symposium on Acute Leukemias (ISAL) 2017 in Munich, Germany. She explains that IDH1 and IDH2 are both enzymes in the citric acid cycle, which, when mutated, produce the oncometabolite 2-hydroxy-glutarate, which inhibits cellular differentiation. Because IDH1 and IDH2 mutations always occur in certain positions, it has been easy to develop inhibitors, which are currently in Phase II and Phase III trials. Dr Thol describes that Phase II results show that inhibition can reverse the differentiation block in AML patients with IDH1 and IDH2 mutations, including relapsed and refractory patients. She argues that IDH1 and IDH2 inhibition may be a promising approach in patients where no alternative treatments are available.