Chimeric antigen receptor (CAR) T-cell therapy may help patients with treatment-resistant lupus achieve sustained remission and robust vaccine response, according to a press release from the American College of Rheumatology (ACR). A small trial from 2022 demonstrated that CAR T cells engineered to target the CD19 protein helped five patients achieve drug-free remission for up to 8 months following infusion. In a follow-up study, presented by Schett et al at ACR Convergence 2023, researchers examined the outcomes of eight patients who received a single dose of 1 million CD19-targeted CAR T cells/kg of body weight from March 2021 to June 2023—with the goal of determining whether remission could be sustained past 8 months and whether depleting B cells would reduce vaccine response. The researchers further measured disease activity; autoantibody levels; and responses to measles, mumps, rubella, varicella zoster, Epstein-Barr, tetanus, and pneumococcal vaccines. After 2 years of follow-up, all treated patients experienced lupus remission, had disease activity scores of 0, were not taking immunosuppressants, and had robust vaccine responses. Further, despite the reemergence of naive B cells, the patients’ autoantibodies disappeared following CAR T-cell therapy and remained negative until follow-up—with the exception of one autoantibody in one of the patients. Despite the positive results of the study, CAR T-cell therapy can be costly and result in potentially severe toxicities. However, the researchers noted that patients with lupus who receive CAR T-cell therapy may experience fewer complications and can offset the costs by several years by not requiring expensive lupus drugs. “We are intrigued by the possibility that a deep B-cell depletion exerted by CAR T cells could lead to permanent eradication of the autoimmune disease,” concluded lead study author George Schett, MD, a rheumatologist at the University Hospital Erlangen.