📊 The Erlangen Results: CAR-T Resets the Immune System
A team at the Friedrich-Alexander University of Erlangen-Nürnberg in Germany, led by rheumatologist Dr. Georg Schett and hematologist Dr. Andreas Mackensen, has published the most extensive data to date on CAR-T therapy for autoimmune diseases.
In results published in the New England Journal of Medicine in May 2026, 15 patients with severe treatment-refractory systemic lupus erythematosus treated with a single infusion of CD19-targeted CAR-T cells all achieved drug-free remission, defined as a SLEDAI (Systemic Lupus Erythematosus Disease Activity Index) score of zero, with median follow-up of 2.5 years. All patients were able to discontinue immunosuppressive medications including glucocorticoids, mycophenolate mofetil, and belimumab within three months of treatment.
The scientific rationale is compelling. In autoimmune diseases, B cells produce antibodies that mistakenly attack the body's own tissues. CD19 is a protein expressed on the surface of nearly all B cells, from early precursors through mature plasma cells.
CAR-T cells engineered to recognize CD19 seek out and destroy virtually all B cells in the body, achieving a deep immunological reset. Critically, after the CAR-T cells contract and the B-cell compartment repopulates over the following months, the new B cells in responding patients are predominantly naïve cells that do not produce autoantibodies, suggesting that the root autoimmune defect has been eliminated rather than just temporarily suppressed.
The same Erlangen team has now treated 8 patients with severe diffuse cutaneous systemic sclerosis and 5 with anti-synthetase syndrome, an aggressive form of inflammatory myositis. In systemic sclerosis, 7 of 8 patients showed clinically meaningful reductions in the modified Rodnan skin score, and 5 achieved normalization of lung function decline. Cytokine release syndrome, the main acute toxicity of CAR-T therapy, occurred in approximately 40% of patients but was exclusively Grade 1-2 (fever, mild hypotension) and easily managed with tocilizumab and supportive care.
No patient experienced neurotoxicity, which is the most feared complication of CAR-T therapy in cancer patients and occurs at higher rates due to higher disease burden and tumor lysis.
📋 The Commercial Race
The Erlangen academic results have ignited a commercial race. Kyverna Therapeutics, which raised over $700 million in venture capital, has an ongoing Phase 2 trial of its CD19 CAR-T therapy KYV-101 in lupus nephritis with initial data showing 75% of patients achieving complete renal response at 6 months. Cabaletta Bio's DSG3-CAART for mucosal pemphigus vulgaris entered Phase 2 in 2025.
Bristol Myers Squibb, which acquired Breyanzi and now owns the approved CD19 CAR-T therapies, has launched a dedicated autoimmune cell therapy division and initiated trials in lupus and dermatomyositis.
The addressable patient population is enormous. An estimated 5 million people have lupus worldwide, approximately 1.5 million in the US alone. Systemic sclerosis affects approximately 300,000 people globally, idiopathic inflammatory myopathies another 200,000, and myasthenia gravis approximately 700,000.
If even a fraction of patients with severe, treatment-refractory disease are candidates, the commercial opportunity rivals oncology. However, significant challenges remain: current autologous CAR-T manufacturing costs approximately $150,000-200,000 per patient, and scaling manufacturing infrastructure to serve autoimmune patients (who are generally healthier and outnumber the 30,000 annual CAR-T-eligible oncology patients) would require substantial investment in manufacturing capacity.
Multiple companies are pursuing allogeneic "off-the-shelf" CAR-T therapies using donor cells that could be manufactured in large batches, potentially reducing cost and improving access.