Clinical study of Mito-FLAG regimen in treatment of relapsed acute myeloid leukemia

Patients with relapsed acute myeloid leukemia (AML) have unfavorable prognosis and require innovative therapeutic approaches. In this study we used fludarabine combined with a middle dose of cytosine arabinoside (Ara-C), mitoxantrone and granulocyte-colony stimulating factor (G-CSF) as a salvage therapy for patients with relapsed AML in China. Forty-five patients with relapsed AML were treated with the Mito-FLAG regimen consisting of mitoxantrone (7 mg/m(2), day 1, 3 and 5), fludarabine (30 mg/m(2), days 1-5), Ara-C (1 g/m(2), over 3 h every 12 h, days 1-5) and G-CSF [5 μg/kg/day subcutaneously from day 0 until the white blood count (WBC) was >20×10(9)/l]. Patients with a partial response (PR) received another course of the same regimen. Patients with a suitable donor and aged <50 years received allogeneic stem cell transplantation (allo-SCT). Twenty-three patients (51%) and 3 patients (7%) achieved complete remission (CR) and PR, respectively, following one or two courses of Mito-FLAG, and the overall response (OR) rate was 58%. Nine patients (20%) received allo-SCT and 4 patients (9%) succumbed early. Hematological toxicity and infections were the most prominent toxicities of this regimen. Other toxicities included nausea, vomiting, bleeding, hyperbilirubinemia, renal toxicity and arrhythmia. The probability of overall survival (OS) at 4 years was 19% (95% CI, 11-26%) and the probability of 4-year disease-free survival (DFS) was 29% for all 23 patients in CR (95% CI, 18-41%). Our data suggest that Mito-FLAG is a highly effective and well-tolerated salvage regimen for relapsed AML.