Mitoxantrone (M) is a synthetic aminoanthraquinone with anti-leukemic activity in patients with daunorubicin (D) resistant acute leukemia. The Cancer and Leukemia Group B (CALGB) has undertaken a limited access pilot study in which M, 12 mg/m2, over 30 min, daily for 3 days, and cytosine arabinoside (Ara-C), 100 mg/m2/day by constant infusion for 7 days were used for the induction of newly diagnosed patients with AML. Responding patients were consolidated with daunorubicin, 45 mg/m2/day for 3 days, and 7 days of Ara-C. After a second consolidation identical to induction, no further therapy was given. Twenty-nine patients with a median age of 50 years (range 18-72) were entered in the study; 18 were males and 11 females. Twenty-four (83%) patients achieved CR, 1 patient achieved a PR, and 4 died in induction from leukemia-related causes. Two patients died in CR from consolidation-related neutropenic sepsis and two additional patients died in CR. Of 24 patients, 7 remain disease-free at a median follow-up interval of 8 years. The regimen is active and well tolerated. The duration of disease-free survival in responding patients is consistent with that seen in similar regimens using intensification chemotherapy without prolonged maintenance.