Venetoclax, ATRA, and ATO for Acute Promyelocytic Leukemia with Hyperleukocytosis

Study start date: July 1, 2025

Inclusion Criteria: 1. Patients diagnosed with acute promyelocytic leukemia (APL) according to bone marrow morphology and immunophenotyping, consistent with the WHO 2016 diagnostic criteria. 2. Age ≥14 years, both male and female patients are eligible. 3. Adequate organ function, defined as: 3.1 Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) ≤3 × upper limit of normal (ULN); 3.2 Total serum bilirubin ≤1.5 × ULN; 3.3 Creatinine clearance ≥30 mL/min; 3.4 Serum cardiac enzymes \<2.0 × ULN. 4. Signed informed consent obtained from the patient or a legally authorized representative. 5. White blood cell (WBC) count \>10 × 10⁹/L at initial diagnosis, or WBC \>10 × 10⁹/L during treatment. Exclusion Criteria: 1. Diagnosis of acute non-promyelocytic leukemia, myeloid sarcoma, or chronic myeloid leukemia in accelerated or blast phase. 2. Known hypersensitivity to any drug included in the study regimen. 3. Pregnant or breastfeeding women, and women of childbearing potential who are unwilling to use effective contraception during the study treatment period. 4. Presence of organic heart disease, such as uncontrolled or symptomatic arrhythmia, congestive heart failure, or myocardial infarction within 6 months prior to screening that resulted in clinical symptoms or impaired cardiac function (NYHA class ≥III). 5. Concurrent malignancies, except for: 5.1 Malignancies treated with curative intent (e.g., hematopoietic stem cell transplantation) and with no known active disease for ≥5 years before enrollment; 5.2 Adequately treated non-melanoma skin cancer or malignant lentigo without evidence of disease, even if diagnosed \<3 years before enrollment; 5.3 Adequately treated carcinoma in situ without evidence of disease, even if diagnosed \<3 years before enrollment. 6. Patients with acquired immunodeficiency syndrome (AIDS) or syphilis, or those with active hepatitis B (detectable HBV DNA) or active hepatitis C infection. 7. Any concurrent medical condition or disease that may interfere with study procedures or outcomes, or that may pose an unacceptable risk to the participant as determined by the investigator (e.g., active systemic infection). 8. Inability to understand or comply with the study protocol. 9. Participation in another clinical study within 1 month prior to enrollment.