Thirteen patients (7 male, 9 female) aged 22 bis 71 years (x = 55 years) with acute non-lymphocytic leukemia and contraindications for anthracyclin therapy were treated with combined chemotherapy using m-amsacrine primarily or in relapse. The main reasons for avoiding cardiotoxic substances were overt cardiac insufficiency and former administration of daunorubicin with more than 540 mg/m2 body surface area. Amsacrine was combined with 6-thioguanine, VP 16–213 and cytosine arabinoside in conventional or high dosage. Eight out of 13 patients (62%) achieved complete remission after one or two courses of chemotherapy. One patient showed partial remission and could be brought into complete remission with another chemotherapy using high-dose ara-C and mitoxantrone. Three patients died in aplasia after chemotherapy and 1 other patient had to be regarded as a complete non-responder. Remission duration and survival time for the 8 successfully-treated patients so far is 1–12 months; however, medians have not yet been reached, since only one of the eight patients relapsed after 6 months of complete remission. These data indicate a high efficacy of m-amsacrine in combined chemotherapy for acute non-lymphocytic leukemia in high-risk patients with contraindications for anthracycl