FLAG-IDA in the treatment of refractory/relapsed adult acute lymphoblastic leukemia

Relapsed or refractory adult acute lymphoblastic leukemias (ALL) have poor prognosis. The strategy for treating these patients is through reinduction chemotherapy followed by allogeneic stem cell transplantation, provided that the toxicity of the salvage regimen is acceptable. Twenty three patients with relapsed/refractory adult ALL were treated with fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin (FLAG-IDA). Five patients had primary refractory disease, and 18 were in first relapse. Nine (39.1%) patients achieved complete remission (CR) following salvage therapy, whereas 13 (56.5%) patients were refractory, and one patient died in aplasia due to infection. In patients achieving remission, the median time to reach absolute neutrophil count (ANC) more than 0.5×10⁹/l and 1×10⁹/l was 20 (range 16–25) and 24 (range 20–28) days from the start of chemotherapy, respectively. Platelet levels of more than 20×10⁹/l and 100×10⁹/l were achieved in a median time of 23 (range 19–25) and 33 (range 28–39) days, respectively. Fever more than 38.5°C was observed in 18 of 23 patients (78.2%), 13 had fever of unknown origin, and 5 had documented infections. Nonhematological side effects, consisting mainly of mucositis (18/23 or 78.2%) and transient liver toxicity increase (10/23 or 43.4%), were generally tolerated. All nine patients who achieved CR received a second course with FLAG-IDA, and seven patients underwent allogeneic stem cell transplantation (four from a matched donor, one from a mismatched donor, and two from an unrelated donor), while two did not reach that stage due to early relapse from CR. The median overall survival (OS) for all 23 patients was 4.5 (range 1–38) months; for the nine responders, the disease-free survival (DFS) and the OS were 6 (range 3–38) and 9 (7–38) months, respectively; the seven patients who received allogeneic stem cell transplantation had a DFS of 10 (range 7–38) months. In our experience, FLAG-IDA is a well-tolerated regimen in relapsed/refractory ALL patients; the toxicity is acceptable, enabling patients who have achieved CR to receive allogeneic transplantation.