IDA-FLAG (idarubicin, fludarabine, cytarabine, G-CSF), an effective remission-induction therapy for poor-prognosis AML of childhood prior to allogeneic or autologous bone marrow transplantation: experiences of a phase II trial

A phase II trial was designed to explore the potential feasibility and efficacy of a reinduction therapy consisting of fludarabine, cytarabine, idarubicin and granulocyte colony stimulating factor (G-CSF) for acute myelogenous leukaemia (AML) patients with poor prognosis.
Twenty-three patients aged 1.2–17.5 years with refractory ( n  = 3), relapsed ( n  = 19) or secondary ( n  = 1) AML were treated with the IDA-FLAG regimen, a combination therapy of idarubicin (days 2–4, 12 mg/m²/d), fludarabine (days 1–4, 30 mg/m²/d), cytarabine (days 1–4, 2000 mg/m²/d) and G-CSF (day 0 up to ANC > 1 × 10⁹/l, 400 μg/m²/d). They received a total of 37 courses of IDA-FLAG and/or FLAG (IDA-FLAG without idarubicin). 17/23 patients achieved a complete remission (CR) with a median duration of 13.5 months (1–39 months), one patient showed a partial remission, and five were nonresponders while in CR, 11 patients underwent bone marrow or PBSC (peripheral blood stem cells) transplantation. Overall, nine patients remain in continuous complete remission with a median duration of 17.5 months (9.5–39 months). The toxicity of the IDA-FLAG courses was more severe than for the FLAG courses with marked neutropenia and thrombocytopenia (for IDA-FLAG: median 22.5 and 25 d respectively; for FLAG: median 10.5 and 14 d respectively). Pulmonary infections were the main nonhaematological toxicity. One patient died in CR from invasive aspergillosis.
The IDA-FLAG regimen produced a CR of >12 months in more than half of the patients and can be recommended as a therapeutic option prior to allogeneic or autologous bone marrow transplantation.