When too late is too late: timing of CAR T-cell therapy in SLE & lupus nephritis.

CAR T-cell therapy has demonstrated the capacity to induce deep, drug-free remissions in patients with severe, refractory systemic lupus erythematosus (SLE), including those with lupus nephritis (LN). These observations challenge long-standing assumptions about the reversibility of autoimmune disease and raise a critical question: whether CAR T-cell therapy should remain a therapy of last resort or if trials could investigate use earlier in the disease course, when its disease-modifying potential may be greatest. When CAR T-cell therapy is administered late in the disease course, its true biologic effect may therefore be underestimated, and clinical nonresponse may be misattributed to lack of therapeutic activity rather than to persistent damage and fibrosis. CAR T-cell therapy is still experimental and undergoing investigation as a treatment option in autoimmune diseases. Given the potential for a durable disease-free, drug free remission, we propose investigating use of CAR T-cell therapy in early severe SLE. We highlight CAR T-cell therapy in SLE and LN with a brief discussion of risks and benefits from the evidence to date. The current positioning as a refractory/salvage therapy late in the treatment algorithm may limit its impact for patients with SLE at high risk of irreversible organ damage.