CAR-T cell therapy targeting CD19 has been shown to be effective in heavily-pretreated B-cell ALL or NHL, but relapses post-CAR-T are common, and CD19 antigen loss is one of the reasons. Thus, the investigators supposed that CD19/CD22 bispecific CAR-T cell therapy would be more effective and less relapses would occur in B- NHL. In this prospective phase 2 clinical trial, the investigators aim to explore the efficacy and safety of CD19/CD22 bispecific CAR-T cell therapy in relapsed/refractory Large B cell lymphoma.

Large B cell lymphoma (LBCL) is the most common aggressive subtype of non-Hodgkin lymphoma (NHL) in adults. While approximately 60% of patients can be cured with first-line therapy, a subset of patients experiences relapse or refractory disease (R/R). The prognosis for R/R LBCL patients is poor, with limited efficacy from traditional treatments such as autologous stem cell transplantation (ASCT) and novel targeted agents. Chimeric antigen receptor-T (CAR-T) cell therapy involves genetically engineering T cells to express chimeric antigen receptors (CARs) that target tumor-specific antigens, enabling precise elimination of tumor cells. CD19 is the most commonly targeted antigen in B-cell malignancies, however, antigen escape following CD19 CAR-T therapy can lead to disease relapse in some patients. Studies indicate that CD22 is widely expressed in B-cell malignancies and exhibits incomplete overlap with CD19 expression, suggesting that dual-target CAR-T therapy may more comprehensively eradicate tumor cells. Therefore, dual-target CAR-T therapy, particularly strategies targeting both CD19 and CD22, has emerged as a promising approach to overcome antigen escape and enhance therapeutic outcomes. In this prospective study, the investigators aimed to evaluate the efficacy and safety of CD19/CD22 bispecific CAR-T cell (CAR2219) therapy in patients with R/R LBCL.

Inclusion Criteria:

• 14 years to 85 years, expected survival > 3 months;
• CD19 positive with or without CD22 positive Large B-cell lymphoma;
• relapsed or refractory disease;
• ECOG-PS score=0-2;
• Having at least one measurable lesion;
• Cardiac function: 1-2 levels;
• Liver: TBIL≤3ULN，AST ≤2.5ULN，ALT ≤2.5ULN;
• kidney: Cr≤1.25ULN;
• bone marrow: WBC ≥ 3.0×10e9/L, Hb ≥80 g/L, PLT ≥ 50×10e9/L;
• No serious allergic constitution;
• No other serious diseases that conflicts with the clinical program;
• No other cancer history;
• No serious mental disorder;
• Informed consent is signed by a subject or his lineal relation.

Exclusion Criteria:

• Pregnant or lactating women (female participants of reproductive potential must have a negative serum or urine pregnancy test);
• Uncontrolled active infection, HIV infection, syphilis serology reaction positive;
• Active hepatitis B or hepatitis C infection;
• With severe cardiac, liver, renal insufficiency, diabetes and other diseases;
• Participate in other clinical research in the past 4 weeks;
• Researchers think of that does not fit to participate in the study, or other cases that affect the clinical trial results.