The aim of this dose-finding study is to find the optimal dose for the combination of idarubicin, cytarabine and G-CSF that could improve the response rate, reduce relapse and improve survival of patients with primary acute myeloid leukemia. This could be a significant advance in a field where treatment outcomes have stabilized in the last 15 years. This study will be the basis for further prospective, randomized, multicenter trial comparing idarubicin maximum tolerated dose, compared to standard treatment with idarubicin and cytarabine, including raising both arms in G-CSF. The dose of 12 mg/m2 will be administered as control arm in this future randomized study, which will investigate the benefit of enhanced dose identified as optimal in this phase II pilot study.