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.