Clinical Study of Venetoclax Combined With Azacitidine as Bridging Therapy Prior to Hematopoietic Stem Cell Transplantation in Patients With Higher-Risk Myelodysplastic Syndromes

Inclusion Criteria:

1. Newly diagnosed MDS confirmed by morphological and immunophenotypic analysis of bone marrow；
2. Age ≥18 years, any gender；
3. Bone marrow blasts ≥10%；
4. IPSS-R score \>4.5；
5. ECOG performance status 0-2；
6. Scheduled for allogeneic hematopoietic stem cell transplantation (allo-HSCT)；
7. Adequate major organ function：

   * Cardiac: LVEF ≥50%
   * Hepatic: Bilirubin ≤1.5×ULN
   * AST/ALT ≤2.5×ULN
   * Renal: Creatinine clearance ≥60 mL/min；
8. Written informed consent provided by the patient or legally authorized representative.

Exclusion Criteria:

1. Extramedullary disease involvement；
2. Hypersensitivity to any study drugs；
3. Clinically significant hepatic/renal dysfunction exceeding inclusion thresholds；
4. Severe cardiac disease, including congestive heart failure, myocardial infarction, and cardiac insufficiency;
5. Concurrent malignant tumors of other organs, which can be enrolled if previously cured;
6. Active tuberculosis or HIV infection;
7. Concomitant hematologic disorders;
8. Pregnancy or lactation;
9. Inability to comply with protocol requirements;
10. Concurrently participating in other clinical studies.