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Objectives CTA313 is a B-cell–directed cell therapy incorporating proprietary edits designed to improve in vivo kinetics and therapeutic durability.Methods Pts with SLE/LN received a single administration of CTA313 treatment at 3 dose levels (DLs): DL1 3×106 CAR+ T cells/kg, DL2 6×106 CAR+ T cells/kg, DL3 10×106 CAR+ T cells/kg following standard dose lymphodepletion. CTA313 cellular kinetics were assessed by qPCR. Peripheral B-cell counts were monitored through ~Day 182. Clinical activity assessments include disease activity scores (SLEDAI-2K), Physician’s Global Assessment (PGA) and renal outcome measurements.Results As of December 25, 2025, 18 patients received CTA313 at three doses, DL1 (n=4), DL2 (n=8), DL3 (n=6). 16 (89%) pts were female, median age 36 (21-50) years, and median disease duration 7 (1-17) years.Regarding immune related toxicities only Grade 1 CRS was observed in 8 patients (44%); no neurotoxicity or GvHD have been reported.CTA313 demonstrated robust early expansion, with median Cmax of 253,940 copies/ug DNA, and sustained detectability with median persistence of 42 days. Importantly, in most (67%) CAR-T persistence was measured at >= 28 days. CTA313 treatment led to profound peripheral B-cell depletion with a prolonged nadir, followed by gradual repopulation beginning ~Day 42 and continuing to at least ~6 months. Reconstituting B cells were initially dominated by a naïve phenotype at Day 42, with limited representation of memory/activated subsets across subsequent monthly assessments. Serologically, B-cell elimination was associated with marked, sequential reduction in circulating immunoglobulins with earlier recovery of IgM relative to IgA and IgG during reconstitution consistent with half-live. Anti-dsDNA antibody declined rapidly to undetectable levels and remained suppressed through follow-up; anti-Rubella titers from prior vaccination also remained undetectable.Eighteen pts have reached initial assessment; with a mean follow up of 6 months 100% of pts achieved SRI-4 response, 78% (14/18) achieved LLDAS, 50% (9/18) achieved DORIS remission. Among pts with a follow up >= 6 months, 60% (6/10) achieved DORIS remission.Conclusions CTA313 produces deep, durable B-cell depletion followed by predominantly naïve B-cell and immunoglobin repopulation, sustained suppression of pathogenic autoantibodies, and antiviral vaccine titers—an immunologic profile consistent with an immune-reset mechanism that may enable prolonged remission in autoantibody-mediated autoimmune disease.