PURPOSE To determine the optimal daunorubicin dose and number of 7 + 3 induction cycles in newly diagnosed AML, this randomized controlled trial compared a once daily dose of 60 mg/m2 with 90 mg/m2 daunorubicin in the first 7 + 3 induction and one versus two cycles of 7 + 3 induction. PATIENTS AND METHODS Patients age 18-65 years with newly diagnosed AML were randomly assigned to 60 versus 90 mg/m2 daunorubicin once daily plus cytarabine. Patients with marrow blasts below 5% on day 15 after first induction were randomly assigned to receive a second induction cycle or no second induction cycle. RESULTS Eight hundred and sixty-four patients with a median age of 52 years were randomly assigned. After a preplanned interim analysis showing no significant difference in response between 60 and 90 mg/m2, all consecutive patients received 60 mg/m2 daunorubicin once daily. The proportion of good early responders was 44% versus 48% (P = .983) with a composite complete remission (CRc) rate of 90%