Secondary Infusion of Relma-cel Injection for Relapsed or Refractory B-cell Lymphoma

Inclusion Criteria: * Patients have signed an Informed Consent Form (ICF). * Adults diagnosed with relapsed or refractory B-cell lymphoma who have completed initial treatment with Relma-cel. * Patients must have undergone at least one disease assessment post-initial Relma-cel treatment, and the investigator decides to administer a second treatment (including PR/PD/SD) based on clinical practice. * Before the second infusion, confirm that the prepared dose of relma-cel is sufficient (recommended 80-150 x 10\^6 CAR-T cells), with specific dosage determined by the investigator based on patient condition and dose availability. * Confirm the presence of CD19+ residual tumor tissue, if clinically permissible. * Measure plasma for the absence of anti-drug antibodies (ADA) to relma-cel before the second treatment. * Toxicity related to lymphodepleting chemotherapy (fludarabine and cyclophosphamide), except for hair loss, must have resolved to ≤ Grade 1 or returned to baseline levels before retreatment. * Patients must not have experienced severe adverse reactions during the first treatment, or any adverse reactions must have resolved to baseline levels from the first treatment. Exclusion Criteria: * Patients with hypersensitivity to active ingredients or any excipients (e.g., dimethyl sulfoxide, compound electrolyte injection, human albumin). * Patients with uncontrolled systemic fungal, bacterial, viral, or other infections