Clinical response in patients with R/R MM to BCMA CAR T-cell therapy and immune signatures of patients with APBs. (A) Duration of response to CAR T cells and postinfusion survival in 12 patients with R/R MM. Cyan dots indicate that patients developed APBs after CAR T-cell infusion. (B-C) Progression-free survival (PFS) and overall survival of patients with MM with or without APBs after CAR T-cell therapy (mean ± standard error of the mean [SEM]). (D) Response of patients with MM with or without APBs after CAR T-cell therapy. (E-G) Count of blood B cells, T cells, and natural killer (NK) cells (mean ± SEM). (H) Ratio of CD4⁺ and CD8⁺ cells. (I-J) Percentage of CD4⁺ and CD8⁺ cells in blood lymphocytes. *P < .05. #Patients without APBs vs patients with APBs. MRD, minimal residual disease; PD, progressive disease; PR, partial response; SD, stable disease; VGPR, very good partial response.