Mitoxantrone for refractory and relapsed acute leukemia.

Seventy-seven patients with relapsed or refractory acute leukemia and three with acute blastic chronic myeloid leukemia (CML) were treated in an open Phase II study using mitoxantrone 12 mg/m2 intravenously daily X 5 days. Complete remission (CR) was achieved in 32 of 80 (40%), including 23/45 (52%) with relapsed acute nonlymmphocytic leukemia (ANLL), four of 12 (33%) with relapsed acute lymphocytic leukemia ALL, four of 17 (24%) with ANLL refractory to daunorubicin + cytosine arabinoside, and one of three (33%) with refractory ALL. None of the patients with acute blastic CML achieved CR. Median survival time for all patients was 121 days. Median duration of complete response was 303 days with ten of 32 patients in continuing CR for periods varying from 44+ to 1210+ days. Apart from moderately prolonged hematologic suppression toxicity was mild and subjective side effects were tolerable. Mitoxantrone is an active agent in the treatment of acute leukemia and demonstrates incomplete cross resistance with duanorubicin. Mitoxantrone should be considered for first-line therapy in ANLL.