Abstract Background Oral azacitidine improves survival in patients with AML in first complete remission who are not candidates for allogeneic transplantation. Most favorable-risk AML patients harbor molecular markers enabling sensitive measurable residual disease (MRD) monitoring. While MRD is a well-established prognostic factor in AML, the clinical significance of MRD dynamics during maintenance therapy remains incompletely defined. Methods We conducted a multicenter, real-world retrospective study of 30 patients with AML, predominantly ELN favorable-risk, treated with oral azacitidine maintenance following intensive induction-consolidation. MRD was assessed longitudinally using standardized molecular and flow-based assays. Outcomes were analyzed according to MRD status at maintenance initiation and subsequent MRD conversion. Results At initiation of oral azacitidine, 47% of patients were MRD-positive. MRD conversion to negativity occurred in 64% of these patients during maintenance. Relapse-free survival (RFS) was comparable between patients who were MRD-negative at baseline and those who converted to MRD negativity (24-months restricted median RFS 577 vs. 638 days), whereas patients with persistent MRD positivity experienced early relapse (24-months restricted median RFS 63 days). Despite inferior RFS, overall survival did not significantly differ between MRD-defined groups. Patients relapsing after oral azacitidine retained sensitivity to subsequent therapies, including venetoclax–azacitidine–based regimens, with high rates of molecular response. Conclusions Oral azacitidine was associated with high rates of MRD conversion, conferring RFS comparable to patients who were MRD-negative at treatment initiation. Persistent MRD identified patients at high-risk for early relapse, while effective salvage therapies mitigated overall survival differences. These findings support prospective evaluation of MRD-guided maintenance strategies in favorable-risk AML but should be considered hypothesis-generating given the retrospective design and limited cohort size. The trial is on behalf of the Israel Acute Leukemia Group.
Hurvitz et al. (Fri,) studied this question.