Ninety-seven patients less than or equal to 70 years of age with previously untreated primary acute myeloblastic leukemia were randomly treated with either the DAT or TAD regimen: daunorubicin (70 mg/m2/day) administered on Days 1-3 (DAT) or 5-7 (TAD) of a 7-day sequence consisting of cytarabine (200 mg/m2/day) and 6-thioguanine (200 mg/m2/day). Complete responders received consolidation, maintenance, and final intensification over 14 months using mostly the same drugs as during induction and administered in the same sequence. The regimens did not significantly differ from each other with regard to toxicity or efficacy. Complete remission rate was 80% in the two groups, and median duration of complete remission was 549 days with DAT and 518 days with TAD.