A Prospective Single-Arm Study of VABu Conditioning Regimen in Allo-HSCT for Low-Performance or High-Comorbidity AML Patients in CR1

This study evaluates the effectiveness and safety of a new conditioning regimen called VABu before stem cell transplantation in patients with acute myeloid leukemia (AML) who are in their first complete remission (CR1), classified as non-high-risk per ELN 2022 guidelines, but have poor physical condition (ECOG performance status ≥ 2) or high comorbidity burden (HCT-CI ≥ 2). VABu combines venetoclax, azacitidine (or decitabine as an alternative), and busulfan. This is a single-arm, prospective study with 42 participants. All participants will receive the VABu regimen followed by stem cell transplantation. The primary outcome measure is 2-year overall survival (OS). Secondary outcomes include 2-year relapse-free survival (RFS), transplant-related mortality (TRM), engraftment failure rate, bloodstream infection (BSI), and 2-year all-cause mortality and non-relapse mortality (NRM). The study is conducted at the First Affiliated Hospital of Soochow University.

Inclusion Criteria: 1. Age 18 to 70 years. 2. Diagnosis of acute myeloid leukemia (AML) other than acute promyelocytic leukemia (APL), with first complete remission (CR1) achieved after induction chemotherapy. 3. Classified as non-high-risk per ELN 2022 risk stratification guidelines. 4. ECOG performance status ≥ 2 (not due to leukemia) OR Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) ≥ 2. 5. Willing to undergo allogeneic hematopoietic stem cell transplantation and has a suitable donor. 6. Voluntarily signs informed consent form after full understanding of the study. Exclusion Criteria: 1. Allergy to any component of the study drugs. 2. Psychiatric or psychological disorders that prevent cooperation with treatment. 3. Uncontrolled systemic or local severe infection. 4. Severe dysfunction of major organs (heart, lung, liver, kidney) that, in the investigator's opinion, makes the patient unsuitable for enrollment. 5. Currently participating in or planning to participate in any other clinical study. 6. Any other conditions that, in the investigator's opinion, make the patient unsuitable for enrollment.