CD22-directed CAR T-cell therapy for large B-cell lymphomas progressing after CD19-directed CAR T-cell therapy: a...

Area of Science:

• Immunotherapy
• Hematologic Oncology
• Cellular Therapy

Background:

• Outcomes for large B-cell lymphoma (LBCL) patients relapsing after CD19-directed chimeric antigen receptor (CAR) T-cell therapy (CAR19) are poor.
• CD22 is a B-cell surface antigen with potential as a therapeutic target.
• The efficacy of CD22-directed CAR T-cell therapy (CAR22) in LBCL remains to be determined.

Purpose of the Study:

• To evaluate the efficacy and safety of CD22-directed CAR T-cell therapy (CAR22) in patients with LBCL.
• To identify the maximum tolerated dose (MTD) for CAR22 therapy.
• To explore CAR22 as a potential treatment for patients with LBCL who have relapsed after CAR19 therapy.

Main Methods:

• A single-center, open-label, dose-escalation phase 1 trial.
• Intravenous administration of CAR22 at two dose levels (1 million and 3 million CAR T cells/kg).
• Primary endpoints included manufacturing feasibility, safety (adverse events, dose-limiting toxicities), and MTD identification.

Main Results:

• CAR22 product manufacturing was feasible in 95% of patients.
• The maximum tolerated dose was identified as 1 million CAR T cells per kg.
• No dose-limiting toxicities or severe (grade ≥3) cytokine release syndrome, neurotoxicity, or hemophagocytic lymphohistiocytosis-like syndrome were observed at the MTD.

Conclusions:

• CD22 is a viable immunotherapeutic target in LBCL.
• CAR22 demonstrates durable clinical activity in patients with LBCL progressing after CAR19 therapy.
• Further investigation is warranted to confirm long-term efficacy and identify optimal patient subgroups.