The purpose of this study is to estimate the efficacy of immunotherapy with ex vivo expanded haploidentical NK cells as consolidation therapy for children/young adults with intermediate risk AML.

Immunotherapy with NK cells may improve the treatment results in AML. For better efficiency high cell doses or several infusions of NK cells are required. For this purpose, donor NK cells are expanded in the presence of feeder K562-mbIL21-41BBL cell line. The cycle of immunotherapy includes chemotherapy (cyclophosphamide, fludarabine) followed by two doses of NK cells infusion.

Inclusion Criteria:

Patients:

• primary intermediate risk AML in molecular complete remission;
• primary high risk AML in molecular complete remission awaiting unrelated HSCT;
• Karnofsky or Lansky performance scale greater or equal to 70;
• written informed consent.

Donors:

• haploidentical family donor;
• donor suitable for cell donation and apheresis according to standard criteria;
• written informed consent.

Exclusion Criteria:

Patients:

• uncontrolled infection;
• severe hepatic dysfunction: SGOT or SCPT >=5x upper limit of normal for age;
• positive serology for human immunodeficiency virus (HIV).

Donors:

• pregnancy;
• positive serology for HIV, hepatitis B or C.