- Subject has a diagnosis of acute myeloid leukemia (AML) according to WHO classification (2008) and has received a high dose or a reduced intensity conditioning allogeneic Hematopoietic Stem Cell Transplant (HSCT) during first or second remission and within 30 to 60 days prior to first dose of AC220. Donors may be human leukocyte antigen (HLA)-matched for HLA-A, B, C, DRB1, and DQB1 by high resolution typing, related or unrelated (only a single allele disparity will be allowed for HLA-A, B, or C as defined by high resolution typing) Note: more than one HSCT is allowed