Enhanced CAR T-Cell Therapy for Relapsed Lymphoma

To the Editor: Svoboda et al. (May 8 issue) 1 report on a study of an enhanced chimeric antigen receptor (CAR) T-cell product (huCART19-IL18) in patients with relapsed or refractory lymphoma after previous anti-CD19 CAR T-cell therapy. The durable responses observed after the failure of previous CAR T-cell therapy are remarkable. We noted that patients with previous exposure to CD28-based CAR T cells showed higher peak expansion and a greater likelihood of response to huCART19-IL18 than those with exposure to 4-1BB–based products. The incidence of complete or partial response was 100% (80% complete) in the CD28 subgroup, as compared with 60% . . .