Safety and Efficacy of CAR-T Cell Therapy for Relapsed/refractory Neuroblastoma and Desmoplastic Small Round Cell Tumors: a Single-arm, Open-label Trial.

Title: Safety and efficacy of CAR-T cell therapy for relapsed/refractory neuroblastoma and desmoplastic small round cell tumors: a single-arm, open-label trial. The CART used in this study will be provided by Shanghai YaKe Biotechnology Ltd. Aims: 1. To evaluate the safety and efficacy of GD2/B7H3 CAR-T therapy for relapsed/refractory neuroblastoma, and observe its pharmacokinetic/pharmacodynamic characteristics and the survival of CAR-T cells in relapsed/refractory neuroblastoma patients. 2. To evaluate the safety and efficacy of GD2/B7H3 CAR-T therapy for relapsed/refractory desmoplastic small round cell tumor, and observe its pharmacokinetic/pharmacodynamic characteristics and the survival of CAR-T cells in desmoplastic small round cell tumor patients. Patients: Relapsed/refractory neuroblastoma; Relapsed/refractory desmoplastic small round cell tumor. CAR-T therapy: Lymphodepletion treatment will be performed within 14 days prior to CAR-T cell infusion: intravenous chemotherapy based on fludarabine 25mg/m² and cyclophosphamide 500mg/m² for 1 to 3 days. CAR-T cells will then be infused intravenously, with a dosage of 1.00 to 10.00 × 10⁶/kg of CAR-positive T cells. Research period: CAR-T cell infusion will be followed up for one year, or until adverse events resolve, progression occurs, or the patient transitions to other treatments. Outcome measures: Incidence of adverse events related to CAR-T therapy, as well as their intensity and duration; Pharmacokinetic/pharmacodynamic characteristics of CAR-T in patients and the survival of CAR-T cells. Overall response rate (ORR) after CAR-T cell infusion, including complete response (CR) and partial response (PR); Overall survival (OS), progression-free survival (PFS), event-free survival (EFS), time to progression (TTP), and duration of response (DOR) after CAR-T cell infusion;