This is a prospective, multicenter, open-label Phase Ib/II clinical study designed to evaluate the safety, tolerability, preliminary efficacy, and pharmacokinetics of lisatoclax in combination with R-CHOP or Pola-R-CHP in patients with previously untreated diffuse large B-cell lymphoma (DLBCL).

Inclusion Criteria:

• 1. Voluntarily participate in the clinical study; fully understand and be informed about the study and sign the Informed Consent Form (ICF); willing to comply with and capable of completing all trial procedures.
• 2. Diagnosed with DLBCL according to 2022 revised WHO lymphoma classification standards based on pathological diagnosis by the research center. For the dose-expansion phase, BCL-2 positivity (≥50% by IHC) is required.
• 3. Age 18-70 years.
• 4. No prior systemic anti-lymphoma therapy.
• 5. Adequate organ and bone marrow function.
• 6. At least one measurable or evaluable disease site according to the Lugano 2014 lymphoma efficacy evaluation criteria.
• 7. Eastern Cooperative Oncology Group (ECOG) performance status of 0-2.

Exclusion Criteria:

• 1. Lymphoma involvement in the central nervous system or meninges.
• 2. Active infections.
• 3. Uncontrolled clinical cardiac symptoms or diseases.
• 4. Currently using (or unable to stop at least one week prior to the first dose) a known CYP3A strong inducer or strong inhibitor.
• 5. Pregnant and lactating women, and subjects of childbearing age who do not want to use contraception.
• 6. History of Human Immunodeficiency Virus (HIV) infection and/or Acquired Immunodeficiency Syndrome (AIDS).
• 7. Patients with mental disorders or those unable to provide informed consent