Homoharringtonine, BCL-2 Inhibitor, Rituximab, and Prednisone in Relapsed/Refractory Diffuse Large B-Cell Lymphoma

Phase II Inclusion Criteria

1. Histopathologically confirmed CD20-positive diffuse large B-cell lymphoma;
2. Age ≥18 years at enrollment, regardless of gender, with an Eastern Cooperative Oncology Group (ECOG) performance status of 0-3;
3. Disease is refractory to or progresses within one year after first-line standard therapy containing anti-CD20 monoclonal antibodies and anthracycline-based chemotherapy, or has failed or relapsed after second-line or later standard treatment regimens, or has relapsed after autologous hematopoietic stem cell transplantation (more than 6 months post-transplant);
4. At least one measurable lesion present (as defined by the Lugano 2014 response criteria: measurable lesion is defined as a lymph node lesion with a longest diameter \>1.5 cm on CT axial imaging, or an extranodal lesion with a longest diameter \>1.0 cm, and 18F-FDG PET/CT positive lesion);
5. Able to provide written informed consent and capable of understanding and complying with all study requirements.

Phase II Exclusion Criteria

1. Patients with poor compliance or inability to attend regular follow-up visits;
2. Presence of severe organ dysfunction, as judged by the investigator, that renders the patient unsuitable for participation in this trial;
3. Absolute neutrophil count \< 1.0 × 10⁹/L, platelet count \< 50 × 10⁹/L, or hemoglobin \< 80 g/L (excluding cases due to lymphoma bone marrow infiltration);
4. Other factors, as determined by the investigator, that may lead to forced early withdrawal from the study, such as other serious medical conditions (including psychiatric disorders) requiring concomitant treatment, alcoholism, drug abuse, or family/social factors that may affect patient safety or compliance;
5. History of immunodeficiency, including HIV-positive status, or other acquired or congenital immunodeficiency diseases;
6. Pregnant or breastfeeding women, and fertile patients unwilling to use contraception.
7. Acute or chronic active hepatitis B or C infection, with HBV DNA \> 2000 IU/mL or 10⁴ copies/mL, or HCV RNA \> 10³ copies/mL;
8. Central nervous system (CNS) metastases; however, patients with asymptomatic CNS metastases or those with symptoms that have been treated and stabilized for ≥4 weeks may be eligible;
9. Prior history of allogeneic hematopoietic stem cell transplantation;
10. Cardiac dysfunction: baseline Corrected QT interval (QTc) ≥ 500 ms; Left Ventricular Ejection Fraction (LVEF) \< 45%, or New York Heart Association (NYHA) classification Class III/IV heart failure;
11. Known severe hypersensitivity to benzyl alcohol or any other components of the study drugs;
12. Requirement for concomitant use of strong CYP3A4 inducers due to medical necessity.