Algorithm of MRD assessment and time points at which MRD is considered a clinically relevant biomarker. Blue squares indicate timepoints of assessment and source of material; pink squares indicate timepoints for treatment modification based on a clinical relevant biomarker: for example, if the level of molecular MRD as assessed by qPCR is ≥2% or if there is failure to reduce mutant transcript levels by 3 to 4 log after completion of consolidation chemotherapy, treatment modifications (eg, allogeneic hematopoietic cell transplantation) may be considered; similarly, if patients are still MRD positive by MFC after 2 cycles of intensive chemotherapy or at end of treatment. For patients receiving less intensive therapy, timepoints for assessment and clinical decision making are not yet established. Modified from 2021 ELN MRD recommendations⁶⁷ BM, bone marrow; CBF, core-binding factor. ^aMFC as assessed by LAIP or the DfN method.