4-Demethoxydaunorubicin (Idarubicin) in refractory or relapsed acute leukemias. A pilot study.

Twenty-five adults with previously treated acute leukemia were treated with 4-demethoxydaunorubicin (Idarubicin) with a daily dose of 8 mg/m2 for 3 days intravenously. Complete remission was achieved in 3 of 18 patients with acute nonlymphoblastic leukemia (ANLL) and 2 of 6 with lymphoblastic leukemia. Complete remissions were observed in two of eight ANLL patients refractory to cytarabine, anthracycline, and m-Amsa (amsacrine), indicating a lack of cross-resistance between these drugs and Idarubicin. The median duration of remission was 8 weeks. The main major toxicity of Idarubicin therapy, severe myelosuppression, cannot be considered a toxic effect because it was desired in this case list. Our preliminary results indicate that Idarubicin has significant activity against refractory adult acute leukemia.