We report on a randomized trial aimed to determine the impact of a second consolidative high-dose cytarabine-based chemotherapy (HiDAC) in patients with acute myeloid leukaemia prior to an autologous stem cell transplantation (ASCT). Patients aged 18-60 years, in complete remission (CR) received a first consolidation with daunorubicin and cytarabine at reduced dose. Patients not allocated to allogeneic transplantation received one course of HiDAC and then were randomized to receive an ASCT immediately (HiDAC 1 group) or after one more course of HiDAC (HiDAC 2 group). Out of the 437 initial patients, 351 achieved CR (80%), of those 277 (79%) were eligible for first HiDAC, and 128 (36%) were randomized (HiDAC 1:65, HiDAC 2:63). Overall survival, leukaemia-free survival and cumulative incidence of relapse and non-relapse deaths were 41% and 53% (P = 0.14), 39% and 48% (P = 0.12), 57% and 47% (P = 0.11), 8% and 8% (P = 0.95) for HiDAC 1 and HiDAC 2 groups, respectively. Further studies are warranted with a larger number of patients to test the place of a second course of HiDAC in this setting.