5-azactidine and zorubicin for patients with previously treated acute nonlymphocytic leukemia: a Cancer and Leukemia Group B pilot study.

Twenty-nine adults with advanced acute nonlymphocytic leukemia were treated with an intensive chemotherapy program consisting of 5-azacitidine and zorubicin. Overall, eight patients (28%) achieved a complete remission. Although only one of 19 patients with refractory leukemia responded, seven of ten patients who were treated immediately following relapse from a prior remission achieved another complete remission. The duration of remission ranged from 5 to 33 weeks (median, 14). Treatment resulted in severe toxic reactions including myelosuppression, renal tubular dysfunction, and elevations in liver enzymes. In addition, each of the 15 patients who died of treatment-associated complications had a severe infection. This combination of 5-azacitidine and zorubicin is relatively ineffective for truly refractory leukemia, but it may be a useful alternative following relapse.