Multiple myeloma(MM) is one of the most common hematological malignancies with substantial morbidity and mortality.~In recent years, several new therapies have prolonged survival of patients with MM, but it is still an incurable malignancy of plasma cells.~B-cell maturation antigen (BCMA) is expressed by normal and malignant plasma cells and a small subset of B cells. This specific expression pattern makes BCMA an ideal target antigen for immunotherapies in MM.~BCMA-targeted chimeric antigen receptor (CAR) T cells have exhibited significant efficacy in MM, but relapse due to single-target escape or poor in vivo persistence has been reported.~Dual-targets or sequential infusion have been proposed to reduce relapse and improve outcomes post BCMA-specific CAR T therapies.~CS1 is expressed on pro-B cells and plasma cells especially malignant ones and some evidence suggests it plays a role in stromal cell interaction in the BM tumour microenvironment.~We have constructed a bispecific CAR containing anti-CS1 single chain variable region (scFv) and an anti-BCMA scFv in 4-1BB-containing second-generation formats.~The bispecific CAR T cells have exhibited potent cytotoxicity in various BCMA+ or/and CS1+ MM cells and can effectively eradicate MM cells in xenograft mice models.~This study aims to evaluate prelimary safety and efficacy of the CS1&BCMA CAR T cells in patients with relapsed or refractory MM.
This is a single-center, open-label, single-arm study to evaluate the safety and efficacy of the bispecific CAR T cells targeting CS1 and BCMA in patients with relapsed or refractory multiple myeloma.