Patients included in the study with high risk acute myeloid leukemia or myelodysplastic syndrome as defined will receive an allogeneic transplantation conditioned by either myeloablative or reduced regimen. Following allogeneic transplantation, patients will receive a maintenance regimen combining chemotherapy with azacitidine (aza) and immunotherapy with donor lymphocyte infusion.

Inclusion Criteria:

• Patients with high risk acute myeloid leukemia undergoing allogeneic transplantation with either a familial or an unrelated donor.

High risk AML is defined as :

• AML in CR1 with unfavorable cytogenetics defined by complex caryotype, autosomal monosomy combined or not with other cytogenetics abnormalities inv(3)/t(3,3), t(6;9), t(6;11), t(11;19), del(5q), del(7q).
• AML in CR2 or greater remission prior allogeneic transplantation
• AML in PR or relapse prior allogeneic transplantation
• Or Patients with high risk myelodysplastic syndrome undergoing allogeneic transplantation with either a familial or an unrelated donor.

High risk MDS is defined as :

• MDS with intermediate-2 group and higher risk group according to IPSS criteria
• Age 18 - 70 years.
• Availability of an HLA identical family donor or unrelated donor with matching in 10/10 alleles (HLA-A, B, C, DRB1, DQB1) or maximum of 1 allele or antigen mismatch OR family donor with maximum 1 allele mismatch.
• Conditioning regimen to allogeneic transplantation may be either myeloablative or reduced.
• Be able to understand and sign informed consent.
• Affiliation number to National Health Care System
• Men and women of childbearing potential must use effective contraception during and up to 3 months after treatment.

Exclusion Criteria:

• The presence of any one exclusion criteria renders the patient ineligible:
• Patient in full relapse post-transplant (>20% blasts in the bone marrow) following allogeneic transplant
• Documented leukemic infiltration of CNS/cerebrospinal fluid.
• Karnofsky performance score below 60%.
• Acute and chronic heart failure (NYHA Class III or IV) or symptomatic ischemic heart disease.

following allogeneic transplant

• Severe liver failure (bilirubin >30 μmoles/L, SGPT > 4 X upper limit of normal).
• Hepatic malignancy in advanced stage.
• Severe neurological or psychiatric disorders
• Acute GVHD grade II-III. Patient with grade I GVHD may be included (see annex 1 for GHVD grade definition).
• Active uncontrolled infection.
• Denied informed consent.
• Treatment with other investigational drugs following allogeneic transplantation.
• No effective contraception
• Lactating females
• Pregnant woman