In Vivo CD19/CD20 CAR T-Cell Therapy for Relapsed/Refractory B-Cell Lymphoma

This Phase 1, open-label, single-arm, dose-escalation study is designed to evaluate the safety and tolerability of SL1617 Injection in patients with relapsed or refractory B-cell lymphoma. SL1617 is an investigational in vivo CAR T-cell immunotherapy targeting CD19 and CD20, utilizing an engineered lentiviral vector to generate functional CAR-T cells in vivo without the need for ex vivo cell processing or lymphodepletion. Participants will receive a single intravenous infusion of SL1617 using a traditional 3+3 dose-escalation design. The planned starting dose is 1.0 × 10\^9 transducing units (TU), followed by dose levels of 3.0 × 10\^9 TU and 6.0 × 10\^9 TU. Dose escalation will be guided by the occurrence of dose-limiting toxicities (DLTs).