Fludarabine and cytarabine as continuous sequential infusion for elderly patients with acute myeloid leukemia

A phase II study was conducted to investigate the effects of a therapeutic program based on the combination of fludarabine and cytarabine (ARA-C) administered as a sequential continuous infusion in untreated elderly patients with acute myeloid leukemia (AML).

Sixty-three patients with non-M3 AML, median age 69 years (range 61-81), were accrued. Twenty-four patients (38%) had AML secondary to myelodysplastic syndrome. Fludarabine and ARA-C were administered as a continuous sequential infusion for 72 and 96 hours, respectively, after a loading dose. Patients achieving complete remission (CR) were intended to receive an additional course, followed by autologous stem cell transplantation (ASCT).

Overall, 42 patients (67%) achieved CR. There were 10 induction deaths (16%), while 11 patients were refractory (17%). Among those achieving a remission, 35 patients (83%) received the planned consolidation course and 29 underwent mobilization of CD34+ cells into the peripheral blood for collection, which was successful in 23 (79%). Overall, 17 patients (27% of the whole population) received ASCT. The median overall and disease-free survival were both 10 months.

Patients with an intermediate karyotype and those receiving ASCT had a significantly better clinical outcome. Results in terms of CR achievement, CD34+ cell collection and ASCT feasibility. A longer follow up is needed in order to evaluate the actual benefit on long-term survival.