[A late phase II comparative study of idarubicin + cytarabine and daunorubicin + cytarabine in adult patients with acute non-lymphocytic leukemia. Idarubicin Study Group].

In adult patients with acute non-lymphocytic leukemia (ANLL), idarubicin (IDA) and daunorubicin (DNR) were compared for efficacy and safety in combination with cytarabine (Ara-C). IDA 12 mg/m2/day and DNR 40 mg/m2/day were administered iv bolus for 3 consecutive days (day 1-3), respectively, in combination with Ara-C 80 mg/m2 given by 2-hour intravenous infusion, every 12 hours for 7 consecutive days. The number of evaluable patients was 32 for each group previously untreated. The rates of complete remission (CR) were 59.4% (19/32) in the IDA group and 40.6% (13/32) in the DNR group. The clinical equivalence test with delta = 10% demonstrated that the IDA group is equal or superior in remission rates (p = 0.010) compared to the DNR group. In addition, the Cochran-Mantel-Haenszel test for response means with scores of 3 (CR), 2 (PR) and 1 (NR) showed the significant superiority (p = 0.044) of the IDA group to the DNR group. The duration needed to attain less than 5% leukemic cells in bone marrow tended to be shorter in the IDA group (p = 0.072), and in the CR patients the number of days needed to reach the nadir value in leukemic cells were significantly fewer in the IDA group (p = 0.037). The nadir value of WBC was significantly lower in the IDA group (p = 0.022). As for adverse reactions, high incidences of diarrhea and stomatitis were observed in the IDA group, while the incidences of other adverse reactions were similar between the two groups. When effects of the drug on the ECG were examined, significant changes in ECG parameters were observed in the DNR group after treatment but not in the IDA group. From the above, remission induction in adult AN LL, IDA + Ara-C therapy showed better efficacy than DNR + Ara-C therapy, and IDA was considered to be a drug of first choice in the treatment of ANLL patients.