Researchers at Charité – Universitätsmedizin Berlin conducted the first clinical trial of CAR T-cell therapy for severe, treatment-refractory rheumatoid arthritis, enrolling six patients who had not responded to up to eight prior therapies. The trial, reported in Nature Medicine, demonstrated a substantial decrease in disease activity across all participants, with three achieving sustained remission without medication after up to one year of follow-up. The therapy targets CD19, a surface molecule on B cells, using genetically modified T cells to eliminate disease-driving B cells, including those residing in bone marrow, lymph nodes, and joint tissue.
The treatment led to a temporary depletion of CD19-positive B cells, resulting in a sharp decline in autoantibody levels and the emergence of naïve B cells, suggesting a potential reset of pathological immune memory while largely preserving protective antibody memory from prior vaccinations. Safety observations were encouraging, with only mild-to-moderate, manageable cytokine release syndrome reported. However, responses varied, and one patient experienced disease recurrence after an initial remission. The second phase of the trial will enroll ten additional patients and compare CAR T-cell therapy with an existing B-cell-targeting rheumatoid arthritis drug to further assess efficacy and immune reset effects.
[Source: Charité - Universitätsmedizin Berlin. “A cancer therapy put severe rheumatoid arthritis into remission.” ScienceDaily. 26 August 2026. https://www.sciencedaily.com/releases/2026/08/26082808233.htm]