A Phase III Study Comparing Mesutoclax + Azacitidine Versus Venetoclax + Azacitidine in Untreated Acute Myeloid Leukemia (AML) Patients

Inclusion Criteria:

1. Study participants with newly diagnosed AML (excluding acute promyelocytic leukemia [APL]) confirmed per the 2022 World Health Organization (WHO) classification criteria.
2. Age ≥65 years; or age ≥18 years and <65 years and ineligible for intensive chemotherapy.
3. The participant is expected to have a survival time of at least 12 weeks.
4. For participants aged ≥65 years: ECOG Performance Status (PS) 0-2; for participants aged ≥18 years and <65 years: ECOG PS 0-3.
5. Participants must have adequate hepatic and renal function.
6. Male participants must agree to refrain from unprotected sexual intercourse and sperm donation from the first dose of investigational product through 90 days after the last dose.
7. Female participants must meet one of the following: postmenopausal; permanently sterilized; or, for females of reproductive potential, have a negative serum pregnancy test within 7 days prior to the first study dose. Females of reproductive potential must agree to use one highly effective contraceptive method plus a supplementary barrier contraceptive method with their partner from the date of ICF signature until 180 days after the last dose.
8. The participant is able to communicate adequately with the investigator and comply with study procedures as specified in the protocol.
9. The participant or their legally authorized representative voluntarily provides written informed consent.

Exclusion Criteria:

1. Prior antitumor treatment for myeloid hematologic malignancies.
2. Prior history of chronic myeloid leukemia (CML), myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN).
3. Known central nervous system (CNS) involvement of leukemia.
4. Peripheral blood white blood cell count >25×10^9/L prior to randomization.
5. Active hepatitis B virus or hepatitis C virus infection.
6. History of immunodeficiency, including positive human immunodeficiency virus (HIV) antibody.
7. Use of strong or moderate CYP3A/P-gp inhibitors or inducers (medications, dietary supplements, etc.) within 5 half-lives before the first dose of investigational product.
8. Diagnosis of another active malignant neoplasm within the past 2 years.
9. Severe active infection requiring intravenous antimicrobial therapy.
10. History of severe cardiovascular disease.
11. Prior history of central nervous system disorders.
12. History of severe bleeding diathesis.
13. Known alcohol or substance dependence.
14. Participants whom the investigator judges cannot adhere to the protocol due to uncontrolled medical, psychological, familial, social or geographic conditions; or participants who are unwilling or unable to follow protocol-required procedures.
15. Pregnant or breastfeeding female participants.
16. Malabsorption syndrome or other conditions that preclude oral administration or may interfere with drug absorption.
17. Known hypersensitivity to the active ingredients/excipients of mesutoclax tablets, venetoclax, azacitidine, or mannitol.