A Phase III Clinical Trial of High-dose Rituximab (500mg/m²) Combined With CHOP Regimen in the Treatment of Male Patient With Newly Diagnosed Advanced DLBCL

Key Inclusion Criteria: 1. age \<75y, male patients 2. According to the 2017 Revised WHO Classification criteria for lymphoma, the subject was diagnosed with DLBCL 3. According to Ann Arbor staging, patients were classified as stage III-IV patients 4. No previous anti-tumor systemic therapy or local radiation therapy for DLBCL 5. Expected survival ≥6 months 6. Have sufficient coagulation function and liver and kidney function 7. Haver sufficient bone marrow function 8. All patients should take medically approved contraceptive measures within 12 months after rituximab administration (specific circumstances should follow the listed drug label) 9. Subjects were enrolled voluntarily, signed informed consent, and followed the experimental treatment protocol and visit plan Key Exclusion Criteria: 1. Subjects assessed by the investigator to be intolerant to the R-CHOP regimen and/or any drug therapy; 2. Any previous anti-lymphoma systemic therapy or local radiation therapy 3. Consider patients with lymphoma involving the central nervous system (CNS) or diagnosed with primary CNS lymphoma (PCNSL); The diagnosis was primary mediastinal large B-cell lymphoma (PMBL) 4. Previously received organ transplantation or hematopoietic stem cell transplantation 5. Had received major surgery or major trauma within 4 weeks before the first medication (or before randomization), and had participated in clinical trials of non-anti-tumor drugs or medical devices within 4 weeks 6. Have had malignant tumors other than the indications targeted in this study in the past three years 7. Participants with any serious and/or uncontrolled systemic disease who are determined by the investigator to be unsuitable for participation in the study 8. Major cardiovascular disease occurred within 6 months before the first medication (or before randomization) 9. Any conditions that affect the patient's ingestion of the drug, as well as conditions that seriously affect the absorption or pharmacokinetic parameters of the drug in the trial, including difficult to control nausea and vomiting, short bowel syndrome, etc. 10. Subjects who received live or attenuated vaccine within 4 weeks prior to initial administration (or prior to randomization) or planned to receive live vaccine during the study period or 4 weeks after the end of study treatment 11. A hemorrhagic disease (such as von Willebrand disease or hemophilia A, hemophilia B, etc.) or according to the judgment of the investigator has a clear bleeding tendency 12. have a serious peripheral nervous system or central nervous system disease. 13. Warfarin or other vitamin K antagonists are required during the study 14. There is an autoimmune disease that cannot be controlled or requires treatment within 4 weeks prior to the first dose (or prior to randomization) 15. Doxorubicin has been used in the past ≥150 mg/m2 16. The investigator believes that the subjects have other conditions that are not suitable for participation in this experiment.