The venetoclax combined with metronomic low-dose decitabine and interferon for preventing post-transplant relapse in high-risk MDS and AML patients

Abstract

Abstract Background Post-transplant relapse remains a primary factor limiting long-term survival in high-risk myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study evaluated the efficacy and safety of venetoclax combined with metronomic low-dose decitabine and interferon for preventing post-transplant relapse. Methods A single-center, single-arm retrospective cohort study included 33 high-risk MDS/AML patients who underwent allo-HSCT between January 2022 and January 2024. All patients maintained complete remission with minimal residual disease (MRD)-negative status before maintenance therapy.Phase 1 (6 months): Metronomic decitabine 0.2 mg/kg subcutaneously on days 1, 2, 8, 9, 15, and 16; Venetoclax 200 mg orally on day 1, 400 mg on days 2–21 per 28-day treatment cycle.Phase 2 (6 months, disease progression-free patients): Venetoclax 200 mg (day 1), 400 mg (days 2–21); α-interferon: 30 μg subcutaneously three times weekly per 28-day cycle. Endpoints: Primary: Overall survival (OS), event-free survival (EFS). Secondary: Adverse events (AEs), cumulative incidence of relapse (CIR), non-relapse mortality (NRM), acute/chronic GVHD, and post-transplant viral infections. Results1. OS and EFS: Median follow-up: 22.0 months (95% CI 12.4–27.6). 3 patients deaths and 4 patients relapses (including molecular: 1 case; flow MRD: 1 case; hematological: 2 cases). Median relapse time: 8 months(95% CI 4.2–18.5). 12-month OS: 92.4% (95% CI 72.8–98.0); 24-month OS: 92.4% (95% CI 72.8–98.0). 12-month EFS: 88.2% (95% CI 67.6–96.0); 24-month EFS: 83.0% (95% CI 60.3–93.3). 2. Relapse and NRM: 12-month CIR: 8.5% (95% CI 0–54.0); 24-month CIR: 13.9% (95% CI 0.2–53.3). 12-month NRM: 3.6% (95% CI 0–62.6); 24-month NRM: 3.6% (95% CI 0–62.6). 3. Adverse Events: Neutropenia 69% (grade ≥3: 45%); Thrombocytopenia 41% (grade ≥3: 27%); Infections 21%; GVHD 7%. Conclusion The venetoclax-based metronomic regimen significantly reduces relapse rates in high-risk MDS/AML patients post-allo-HSCT, with a manageable safety profile, supporting its utility as an optimized maintenance strategy for relapse prevention.