Patients with large B-cell lymphoma (LBCL) progressing after anti-CD19 CAR T-cell (CAR19) therapy have poor outcomes. Subsequent CAR T-cell therapy shows promise, but the impact of residual CAR19 and early relapse remains unclear. We evaluated 37 CAR19-refractory LBCL patients who received anti-CD22 CAR T-cell (CAR22) in a phase 1b trial (NCT04088890). Residual CAR19 was unquantifiable in 17 of 33 evaluable patients post-CAR22 infusion. Single-cell RNA sequencing revealed minimal …