CD20, the protein which is expressed on the surface of all mature B cells, is active in many B-cell lymphomas that express this molecule such as Diffuse Large B Cell Lymphoma (DLBCL), the most frequently occurring subtype of non-Hodgkin lymphomas. In clinical practice, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone combination chemotherapy (CHOP) is still considered one of the standard treatment to DLBCL. CMAB304(Retuxira), the chimeric monoclonal antibody is designed to targeted against CD20 for treatment of lymphoma diseases. This trial aimed to observe the safety and efficacy of CMAB304, by added CMAB304 to CHOP chemotherapy regimen compared with CHOP chemotherapy alone.

Rituximab, a chimeric anti-CD20 monoclonal antibody, has been proved valuable treatment for CD20-positive DLBCL. The combination of rituximab with CHOP has been shown to increase both survival and response rate, in comparison to CHOP alone. CMAB304(Retuxira), a biosimilar of rituximab, was developed by Shanghai CP Guojian Pharmaceutical Co.,Ltd. Previous Phase I study showed that CMAB304 was well tolerated as monotherapy and the pharmacokinetic data exhibited a non-linear profile over the dose range of 250 to 500 mg/m2. In this study, efficacy and safety of CMAB304 were evaluated in DLBCL patients.

Inclusion Criteria:

1. Age from 18 to 70 year, male or female
2. Previously untreated
3. DLBCL patients with CD20-positive
4. Lymphoma lesions can be Measured and evaluated; Spiral CT or MR evaluation of the lesion must be ≥ 1cm; Measured by clinical examination or others must be ≥ 2cm
5. Normal blood test, adequate liver and renal function;
6. ECOG score 0~2
7. Life expectancy of greater than 3 months
8. No other malignancy treatment history, except cured carcinoma in situ of the cervix or squamous cell or basal cell skin cancer
9. Signed ICF

Exclusion Criteria:

1. DLBCL transformed from other low-grade NHL types
2. Primary central nervous system lymphoma, or primary gastrointestinal DLBCL
3. History of foreign protein allergies
4. Abnormal liver and/or renal function
5. Suspected or diagnosed central nervous system violation
6. Serious infection or organic diseases
7. Heart disease, heart failure, heart block above second degree, myocardial infarction occurred within six months
8. Breastfeeding or pregnant
9. Leukemia crisis or bone marrow metastases