Salvage Chemotherapy With Sonrotoclax, Cladribine, and Standard-dose Cytarabine, Sequentially Followed by HSCT for R/R AML.

Inclusion criteria

• 1.Patients with a confirmed diagnosis of relapsed or refractory acute myeloid leukemia (AML) based on bone marrow morphology, immunophenotyping, and cytogenetics.
• 2. Patients who are planned to undergo allogeneic hematopoietic stem cell transplantation, including HLA-matched or HLA-mismatched related allogeneic transplantation, as well as unrelated donor transplantation.
• 3. Age between 18 and 65 years, inclusive, regardless of gender.
• 4. Eastern Cooperative Oncology Group performance status (ECOG) of 0-2.
• 5. Written informed consent must be obtained prior to the initiation of any study-related procedures. For patients aged 18 years or older, the consent form may be signed by the patient or by a direct relative. Should the patient's own signature be judged to be potentially harmful to their clinical care, consent may instead be given by a legal guardian or a direct relative.

Exclusion criteria

• 1. Uncontrolled active infection (bacterial, fungal, or viral).
• 2. Known positive serology for human immunodeficiency virus (HIV) or active hepatitis C virus (HCV).
• 3. Psychiatric disorders or other medical conditions that preclude compliance with the study treatment and monitoring requirements.
• 4. Pregnant patients, or patients who are unwilling or unable to use adequate contraceptive measures during the treatment period.
• 5. Prior hematopoietic stem cell transplantation.
• 6. Active cardiac disease, defined as one or more of the following: History of uncontrolled or symptomatic angina pectoris; Myocardial infarction within 6 months prior to study enrollment; History of arrhythmia requiring medication or clinically significant symptomatic arrhythmia; Uncontrolled or symptomatic congestive heart failure (> New York Heart Association [NYHA] class 2); Ejection fraction below the lower limit of normal; Previous coronary angioplasty or stent implantation.
• 7. Severe hepatic impairment, defined as liver function parameters (ALT, TBIL) > 3 × upper limit of normal (ULN); or severe renal impairment, defined as serum creatinine (Cr) > 2 × ULN, or 24-hour urine creatinine clearance < 50 mL/min; or any other condition that, in the investigator's opinion, renders the patient unsuitable for treatment with the study drug.
• 8. Any other condition that, in the investigator's opinion, makes the patient ineligible for study participation.