Dimitrios Kotsos, Carin Hazenberg, Thomas Pabst, Patrycja Gradowska, Markus G Manz, Johan Maertens, Carlos Graux, Marie-Christiane Vekemans, Bjorn T Gjertsen, Sören Lehmann, Catharina H M J Van Elssen, Peter J M Valk, Edo Vellenga, Gert Ossenkoppele, Bob Löwenberg, Marc H G P Raaijmakers, Gerwin Huls, Jurjen Versluis
High-dose chemotherapy (CT), followed by autologous hematopoietic cell transplantation (auto-HCT) or consolidation CT, are postremission strategies for European LeukemiaNet 2022 (ELN2022) favorable- or intermediate-risk patients with acute myeloid leukemia (AML) in complete remission (CR) without measurable residual disease (MRD). We conducted a retrospective, nonrandomized analysis to compare the efficacy and safety of auto-HCT versus CT in newly diagnosed AML patients aged 18-65 years treated within two recent HOVON-SAKK-Nordic trials. From a total of 1005 patients with ELN2022 favorable- or intermediate-risk AML, 224 received busulfan/cyclophosphamide (Bu/Cy), followed by auto-HCT, and 199 received mitoxantrone/etoposide-based CT. The 5-year relapse-free survival (RFS) and overall survival (OS) were comparable between auto-HCT and CT (RFS: 60% vs. 56%, P = 0.70; OS: 72% vs. 71%, P = 0.76). In multivariable analysis, auto-HCT was not associated with a significant difference in RFS (HR 0.80, 95% CI 0.56-1.13, P = 0.20) or OS (HR 0.91, 95% CI 0.60-1.37, P = 0.64). Median time to platelet and neutrophil recovery was shorter with auto-HCT than CT (platelet: 42 vs. 57 days, neutrophil: 13 vs. 39 days). Subgroup analysis revealed that patients achieving CR after the second induction cycle or with baseline white blood cell counts >20 × 109/L had longer RFS with auto-HCT compared to CT (HR 0.17, P = 0.003 and HR 0.48, P = 0.02), which was not observed for OS. Focusing on ELN2022 favorable-risk patients (excluding NPM1mut MRD-positive) and MRD-negative intermediate-risk patients, RFS and OS were not different between consolidation strategies. Collectively, auto-HCT yielded similar RFS and OS to mitoxantrone/etoposide-based CT in favorable- and intermediate-risk AML, particularly in MRD-negative patients, with faster hematologic recovery.