Idarubicin (4-demethoxydaunorubicin) as single agent for remission induction of previously untreated acute promyelocytic leukemia: a pilot study of the Italian cooperative group GIMEMA.

Because of the reported high sensitivity of acute promyelocytic leukemia to daunorubicin, we treated 27 consecutive, newly diagnosed, acute promyelocytic leukemia (APL) patients with the new anthracycline idarubicin (IDA) as induction therapy. IDA dosage ranged from 0.25 to 0.30 mg/kg/day and the drug was administered as single agent during a single induction course of 6 days. A total of 22/27 patients (81%) achieved complete remission, 4 (15%) died during induction and 1 patient was resistant to IDA. Extrahematological toxicity was acceptable. A total of 13/22 patients having achieved CR are still alive and in first CR after a median follow-up of 12 months. As for the treatment of the coagulopathy present in APL: 17/27 (63%) received tranexamic acid (6 g/daily) in continuous infusion for total of 7 d. None of the patients treated with tranexamic acid experienced thromboembolic complications. In conclusion, this multicentric pilot study confirms the antileukemic potency of IDA and the high sensitivity of APL to anthracycline derivatives.