Clofarabine, Etoposide, and Mitoxantrone for Relapsed and Refractory Acute Leukemias

This will be a phase I study with a standard 3x3 design. Patients will proceed to treatment through a series of cohorts with the three drugs being delivered over five days beginning with a dose of Etoposide 100 mg/m2 on days 1-5,Mitoxantrone 8 mg/m2 days 1-3, and clofarabine at 20 mg/m2 IV on days 2-6. Presuming this and subsequent cohorts are tolerable and no more than 1 patient per cohort develops DLT, MTD patients will be treated in cohorts of 3-6 patients up to a final dose level of Etoposide 100 mg/m2 on days 1-5,Mitoxantrone 8 mg/m2 days 1-5, and Clofarabine at 30 mg/m2 IV on days 2-6. Patients failing to enter remission may receive 4 days of therapy with Etoposide 100 mg/m2 on days 1-4,Mitoxantrone 8 mg/m2 days 1-2 or 1-4,and Clofarabine at 20-30 mg/m2 IV on days 1-4. According to established definitions for dose limiting toxicity a recommended phase II dose will be established. After this is established the final cohort will be expanded to 15 patients.