IDO1 and acute myeloid leukemia: For instance, in preclinical studies in AML patients, with the aim of achieving combinatory eradication of MDSCs and redirection of T-cells against AML-blasts by using a CD33/CD3-bispecific BiTE® antibody construct (AMG 330), a reduction in IDO+ CD33+ MDSCs has been observed with boosted AML-blast lysis, thus suggesting that AMG 330 exhibits anti-leukemic efficacy by improving T-cell-mediated cytotoxicity and simultaneous MDSC depletion [231].