Inclusion Criteria:

          -  Diagnosis of acute myeloid leukemia (AML) according to the 2008 criteria of the World
             Health Organization (WHO).

               -  all French-American-British (FAB) subtypes, except:

                  - M3 (acute promyelocytic leukemia)

               -  all cases of de novo AML or secondary AML with ≥ 20 % blasts in peripheral blood
                  and/or bone marrow, except:

                    -  AML secondary to myeloproliferative neoplasms (MPN)

                    -  AML secondary to exposure of leukemogenic agents (t-AML) unless treated with
                       CPX-351 chemotherapy or hypomethylating agents combined with venetoclax.

          -  Completion of one of the following treatment options:

               -  I) Intensive chemotherapy:

                    -  (1) at least one cycle of induction chemotherapy and one cycle of
                       consolidation chemotherapy (low-dose cytarabine as consolidation therapy is
                       allowed) OR

                    -  (2) one to two cycles of CPX-351 induction treatment and up to two cycles of
                       CPX-351 consolidation treatment OR

               -  II) Low-intensity chemotherapy:

                    -  (3) at least two cycles to maximum six cycles of hypomethylating agents
                       whether or not combined with venetoclax OR

                    -  (4) at least two cycles to maximum six cycles of low-dose cytarabine
                       combined with venetoclax;

               -  resulting in:

                    -  morphological complete remission (CR), i.e. bone marrow blast count <5% with
                       neutrophil count >1000 cells/µL and platelet count >100,000 cells/µL OR

                    -  morphological complete remission with incomplete blood recovery (CRi), i.e.
                       bone marrow blast count <5% with neutrophil count <1000 cells/µL or platelet
                       count <100,000 cells/µL.

        For the purpose of this study protocol, platelet count must be >50,000 cells/µL.

          -  Interval between the completion of the last intensive chemotherapy administration (in
             case of low-intensity chemotherapy: last cycle (min. 2 to max. 6 cycles) before
             achieving CR or CRi) and the start of vaccination (or the start of follow-up in case
             of the control arm): 6 weeks (minimum) and 16 weeks (maximum) (in case of
             low-intensity chemotherapy: maximum 10 weeks).

          -  Adult (≥ 18 years) at very high risk of relapse according to:

               -  Age ≥ 60 years, and/or

               -  Adverse biological features (e.g. adverse cytogenetics, adverse morphological
                  features, adverse molecular features, hyperleukocytosis (> 100000 cells/µL)), and

               -  Ineligible for or unwilling to receive hematopoietic stem cell transplantation.

          -  WHO performance status: grade 0, 1 or 2 at the time of enrollment. For definition of
             performance status, see: http://www.ecog.org/general/perf_stat.html

          -  Absence of any psychological, familial, sociological, geographical or physical
             condition potentially hampering compliance with the study protocol and follow-up
             schedule; those conditions should be discussed with the patient before study entry.

        Exclusion Criteria:

          -  Participation in any other interventional clinical trial during the study period.

          -  History or concomitant presence of any other malignancy, except for:

               -  non-melanoma skin cancer

               -  carcinoma in situ of the cervix

               -  any other effectively treated malignancy that has been in remission for >5 years
                  or that is highly likely to be cured at the time of enrollment.

          -  Concomitant presence of any immunosuppressive disease (e.g. HIV) or any active
             autoimmune condition, except for vitiligo.

          -  Concomitant use of systemic corticosteroids in immunosuppressive doses (>1 mg/kg/day
             of prednisone, or equivalent dose for other corticosteroid preparations) or any other
             immunosuppressive agent. A minimum of 4 weeks must have elapsed between the last dose
             of immunosuppressive therapy and the first vaccination. Topical corticosteroids are
             permitted, except if applied at the sites of DC injection.

          -  Pregnant or breast-feeding