Fate Therapeutics, a clinical-stage biopharmaceutical company, announced promising preliminary clinical trial results for FT819, an investigational CAR T-cell therapy for people living with systemic lupus erythematosus (SLE) with lupus nephritis (LN), a serious complication of lupus that affects the kidneys. FT819 is an off-the-shelf, iPSC-derived CD19  CAR-T cell therapy aiming to treat lupus through the depletion of B-cells, including B-cells found in secondary lymphoid tissue.  

The updated Phase 1 findings, presented at the American Society of Nephrology's Kidney Week 2026, evaluated the safety of FT819 across 29 patients with autoimmune diseases, and its effectiveness in lupus nephritis. Among two participants with active LN who stopped standard-of-care immunosuppressants (per the study protocol), received FT819 plus bendamustine conditioning, and had follow-up to six months, both achieved a 100% renal response at six months, with an approximately 50% average reduction in proteinuria, a key indicator of kidney damage. Researchers also observed improvements in lupus disease activity and reported fatigue. Across 29 participants with autoimmune diseases who received a single dose of FT819 with less-intensive conditioning, no dose-limiting toxicities or severe cytokine release syndrome were reported, although some experienced infections and low blood cell counts. 

While these findings are preliminary and the Phase 1 study is ongoing, they represent an encouraging step toward CAR T-cell therapy in lupus treatment. The results support Fate Therapeutics' ongoing Phase 2 RECLAIM-LN trial, which will further evaluate FT819 in patients with refractory moderate-to-severe SLE with LN who have not responded adequately to existing treatments. Continue to follow the Lupus Foundation of America for updates on lupus treatments. Learn more about the significance of CAR T-Cell Therapy in lupus care. 

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