Institution: | 1.Department of Hematology,The Second Affiliated Hospital of Xi’an Jiaotong University,Xi’an,China;2.National-Local Joint Engineering Research Center of Biodiagnostics & Biotherapy,The Second Affiliated Hospital of Xi’an Jiaotong University,Xi’an,China;3.Department of Clinical Laboratory,The Second Affiliated Hospital of Xi’an Jiaotong University,Xi’an,China;4.Nanjing Legend Biotech Inc.,Nanjing,China |
Abstract: | BackgroundChimeric antigen receptor (CAR) T cell therapy has demonstrated proven efficacy in some hematologic cancers. We evaluated the safety and efficacy of LCAR-B38M, a dual epitope-binding CAR T cell therapy directed against 2 distinct B cell maturation antigen epitopes, in patients with relapsed/refractory (R/R) multiple myeloma (MM).MethodsThis ongoing phase 1, single-arm, open-label, multicenter study enrolled patients (18 to 80?years) with R/R MM. Lymphodepletion was performed using cyclophosphamide 300?mg/m2. LCAR-B38M CAR T cells (median CAR+ T cells, 0.5?×?106 cells/kg range, 0.07 to 2.1?×?106]) were infused in 3 separate infusions. The primary objective is to evaluate the safety of LCAR-B38M CAR T cells; the secondary objective is to evaluate the antimyeloma response of the treatment based on the general guidelines of the International Myeloma Working Group.ResultsAt data cutoff, 57 patients had received LCAR-B38M CAR T cells. All patients experienced ≥?1 adverse events (AEs). Grade ≥?3 AEs were reported in 37/57 patients (65%); most common were leukopenia (17/57; 30%), thrombocytopenia (13/57; 23%), and aspartate aminotransferase increased (12/57; 21%). Cytokine release syndrome occurred in 51/57 patients (90%); 4/57 (7%) had grade ≥?3 cases. One patient reported neurotoxicity of grade 1 aphasia, agitation, and seizure-like activity. The overall response rate was 88% (95% confidence interval CI], 76 to 95); 39/57 patients (68%) achieved a complete response, 3/57 (5%) achieved a very good partial response, and 8/57 (14%) achieved a partial response. Minimal residual disease was negative for 36/57 (63%) patients. The median time to response was 1?month (range, 0.4 to 3.5). At a median follow-up of 8?months, median progression-free survival was 15?months (95% CI, 11 to not estimable). Median overall survival for all patients was not reached.ConclusionsLCAR-B38M CAR T cell therapy displayed a manageable safety profile and demonstrated deep and durable responses in patients with R/R MM. |