After completion of induction therapy, patients are stratified according to risk group (low-risk [LR] vs medium-risk [MR] vs high-risk [HR]). Patients with low-risk disease are assigned to treatment arm I. Patients with MR or HR disease that is in complete remission (CR) on day 33 are randomized to 1 of 2 treatment arms. These patients are stratified according to status (MR with rearranged MLL vs MR with unknown MLL vs HR).