Bugitinib Combined With Venetoclax and Cytarabine in Relapsed/Refractory Acute Myeloid Leukemia

Inclusion Criteria:

Participants must meet all of the following criteria:

* Age 18-70 years (inclusive), regardless of sex;
* Diagnosis of non-M3 acute myeloid leukemia (AML), and meeting at least one of the following conditions:

  * Failure to achieve complete remission (CR) after standard induction chemotherapy;
  * First CR duration ≤12 months;
  * First CR duration \>12 months, followed by relapse and failure of at least one line of standard chemotherapy;
  * Relapsed disease after ≥2 prior lines of therapy;
* Eastern Cooperative Oncology Group (ECOG) performance status of 0-2;
* Estimated life expectancy ≥3 months;
* Adequate organ function, defined as:

  * Cardiac: left ventricular ejection fraction (LVEF) ≥50% by echocardiography, with no clinically significant ECG abnormalities;
  * Renal: serum creatinine ≤2.0 × upper limit of normal (ULN) and creatinine clearance ≥60 mL/min (Cockcroft-Gault);
  * Hepatic: ALT and AST ≤3.0 × ULN;
  * Total bilirubin ≤2.0 × ULN (≤3.0 × ULN for patients with Gilbert syndrome);
  * Oxygen saturation ≥92% on room air;
* Ability to take oral medications and comply with study procedures;
* Willingness to participate and provide written informed consent.

Exclusion Criteria:

Participants meeting any of the following criteria will be excluded:

* Known hypersensitivity to any study drug or its excipients;
* Active central nervous system (CNS) leukemia (patients with prior CNS involvement who achieved complete remission and are clinically stable may be eligible);
* Active, uncontrolled bacterial, viral, or systemic fungal infection;
* Known hereditary bleeding or coagulation disorders, history of non-traumatic bleeding or thromboembolism, or other conditions that may increase bleeding risk;
* Evidence of active infection, including:

  * Hepatitis B virus (HBV) infection with positive HBsAg or HBcAb and HBV DNA \>100 copies/mL;
  * Hepatitis C virus (HCV) antibody positive with detectable HCV RNA;
  * Human immunodeficiency virus (HIV) infection;
  * Positive test for syphilis;
* Active bleeding or clinically significant bleeding tendency, including but not limited to:

  * Active gastrointestinal bleeding, intracranial hemorrhage, or bleeding in other vital organs;
  * Grade ≥3 bleeding event within 4 weeks prior to enrollment (per CTCAE);
  * Known hereditary bleeding disorders (e.g., hemophilia);
  * Severe platelet dysfunction not correctable;
* Significant cardiovascular disease, including but not limited to:

  * New York Heart Association (NYHA) class III-IV heart failure;
  * Myocardial infarction or coronary artery bypass grafting (CABG) within 6 months prior to enrollment;
  * Clinically significant ventricular arrhythmias or unexplained syncope (excluding vasovagal or dehydration-related causes);
  * Severe cardiomyopathy;
* History of or concurrent other malignancies (except for adequately treated basal cell carcinoma of the skin or carcinoma in situ of the cervix);
* Clinically significant central nervous system disorders (e.g., epilepsy, stroke, psychiatric disorders) that may affect compliance or safety;
* Participation in another interventional clinical trial within 30 days prior to enrollment;
* Pregnant or breastfeeding women, or subjects planning pregnancy during the study period or within 6 months after the last dose and unwilling to use effective contraception;
* Known or suspected drug abuse or alcohol dependence;
* Requirement for concomitant use of strong CYP3A inhibitors or inducers that cannot be discontinued or dose-adjusted per protocol;
* Any other condition that, in the investigator's opinion, would make the subject unsuitable for participation.