The previous Italian national trial (AIEOP-AML-2002/01) on children with acute myeloid leukemia (AML) achieved a 3-year overall (OS) and event-free survival (EFS) of 72.3% and 59.1%, respectively. In this study (AIEOP-AML-2013), we evaluated if refined patient’s stratification in 3 groups and a second induction with randomization could improve outcomes.

In the new AIEOP-AML-2013, patients were stratified into 3 groups [standard-(SR), intermediate-(IR) and high-risk (HR)] mainly according to genetic criteria and centralized assessment of multiparametric flow-cytometry measurable residual disease (MFC-MRD). The 1st induction course was common for all patients [idarubicin-cytarabine-etoposide (ICE)]. IR and HR patients were then randomized to receive either a 2nd ICE or the fludarabine-cytarabine- liposomal-doxorubicin (FLA-My) scheme as second induction. IR patients with HLA-compatible sibling, and all HR patients were consolidated with allogeneic hematopoietic stem cell transplantation (allo-HSCT), while the remaining IR and SR patients were consolidated with chemotherapy only. Data cut-off was February 1, 2024.

From June/2015 to June/2022, 371 patients were enrolled in the trial. Twenty-six children (7%) experienced primary induction failure, while only 3 patients died during the 2 induction courses. The cumulative incidence of 3-year non-relapse mortality in continuous complete remission was 6.8%. The proportion of patients allocated to the SR, IR, and HR groups were 19.5%, 22%, and 58.5%, respectively. Three-year cumulative incidence of relapse was 18.9%. The 3-year probabilities of OS and EFS were 83.9% and 68.5%, respectively, both values being significantly better (p = 0.001) than those of the AIEOP-AML-2002/01 study. The 3-year OS of SR, IR, and HR patients were 97.0%, 84.2%, and 79.4%, respectively, (p = 0.01). The probability of EFS did not differ in IR and HR randomized to receive either a 2nd ICE or the FLA-My scheme course. Levels of MRD after the 1st and 2nd induction course strongly influenced the EFS probability.

A significant improvement in the outcomes of children with de novo AML was obtained with refined risk-stratification and risk-adapted therapy. FLA-My did not offer any advantage over repeating a 2nd ICE as 2nd induction course.

This study was registered in the European Clinical Trials Database (EudraCT 2014-000652-28).