The study will compare the efficacy of the 2 treatments in intermediate and high-risk APL patients in achieving first hematological complete remission and molecular remission.

Inclusion criteria:

1. Patients with untreated newly diagnosed and genetically proven APL (leukemic cells at diagnosis with the t(15;17) and/or the PML/RARα rearrangement by RT-PCR; the presence of additional cytogenetic lesions is not considered an exclusion criterion) with intermediate and high risk disease.
2. Male and female patients age > 18 years and < 61 years.

Exclusion criteria:

1. Low risk patients (WBC < 10 x 109/L and platelets > 40 x 109/L).
2. Absence of PML-RAR α rearrangement in leukemic cells after successful RNA extraction and amplification of control gene.
3. Pretreated APL.