ATG indicates antithymocyte globulin; autoPBSCT, autologous peripheral blood stem cell transplantation; con, consolidation chemotherapy; CsA, cyclosporin A; CR, complete remission; cytokine response, intracellular cytokine response as detected by flow cytometry after stimulation with WT1 peptide in percent (%) of CD3⁺CD8⁺ T cells, a cytokine response was considered positive if the percentage of WT1 peptide–specific cytokine producing CD3⁺CD8⁺ T cells was at least 2-fold the percentage of an HIV control peptide; Ind, induction chemotherapy; low araC, low-dose cytarabin; mPFS, modified progression-free survival (in case progression occurred prior to 6th vaccination, subsequent time was estimated from first vaccination until subsequent progression); na, not available; Patient no., order of inclusion into study; PD, progressive disease; PFS, progression-free survival; PR, partial remission; reind, reinduction chemotherapy; SD, stable disease; Tetramer⁺ T cells, WT1-specific tetramer-positive T cells in percent (%) of CD3⁺CD8⁺ T cells, which were considered positive, if the frequency of tetramer-positive CD3⁺CD8⁺ T cells at baseline exceeded 0.3%, which was the mean + 2 SDs (0.16% + 0.14%) observed in 12 healthy control subjects; tetramer response, an increase of at least 2-fold in frequency as compared to baseline was considered as vaccine-induced response; type, AMLs were classified according to the WHO classification (patients belonging to the category ″AMLs not otherwise categorized″ are subclassified according to the old FAB classification): all other patients belonged to the second group of the WHO classification (WHOII = ″AML with multilineage dysplasia- with prior MDS″); and vacc, vaccination.