Practical Clinical Study of Dual-targeting BCMA-GPRC5D CAR-T Cell Therapy for Extramedullary Infiltration in Refractory/Relapsed Multiple Myeloma
This is a multicenter, open-label, non-randomized, single-arm clinical trial. Patients with relapsed/refractory multiple myeloma accompanied by extramedullary infiltration will receive BCMA - GPRC5D CAR-T cell therapy. The primary objective is to prospectively evaluate the safety of dual-targeting BCMA and GPRC5D CAR - T cell therapy for extramedullary infiltration in relapsed/refractory multiple myeloma. The primary endpoints are to assess the type and incidence of dose-limiting toxicity (DLT) within one month after the reinfusion of BCMA-GPRC5D CAR-T cells in patients, as well as the incidence and severity of adverse events within one month after the reinfusion. It is expected that no more than 18 participants will be recruited.
• Voluntarily participate in the trial and have good compliance.
• Aged between 18 and 75 years old, regardless of gender.
• Diagnosed with relapsed or refractory multiple myeloma according to the criteria of the International Myeloma Working Group (IMWG)2, and have measurable extramedullary lesions due to multiple myeloma.
• Positive for BCMA and GPRC5D in flow cytometry of bone marrow or cerebrospinal fluid tumor cells or immunohistochemistry of tumor tissue.
• Organ functions: ① Cardiac function: Left ventricular ejection fraction \> 50% (by echocardiogram) in the past 2 weeks. ② Liver function: Alanine aminotransferase and aspartate aminotransferase \< 3 times the upper limit of normal (ULN). ③ Renal function: Creatinine clearance rate ≥ 40 mL/min (by Cockcroft and Gault formula). ④ Coagulation function: PT and APPT \< 1.5 times the ULN. ⑤ Arterial oxygen saturation (SpO₂) \> 95%. ⑥ Pulmonary function: FEV₁% predicted value ≥ 50%.
• Female patients of childbearing age must have a negative serum pregnancy test at screening and before receiving cyclophosphamide and fludarabine or melphalan treatment; male patients should be willing to use effective contraceptive methods for 1 year after receiving the study treatment.
• ECOG score ≤ 2.
• Expected survival time \> 3 months.