Fate Therapeutics Initiates Potentially Registrational Trial of Off-the-Shelf CAR T-Cell Therapy FT819 for Lupus Nephritis

Fate Therapeutics has initiated RECLAIM-LN (NCT07570862) and treated the first patient in its phase 2 potentially registrational clinical trial of FT819 in patients with refractory moderate-to-severe systemic lupus erythematosus (SLE) with Class III or IV lupus nephritis.¹ The first patient was dosed in an outpatient setting and discharged the same day, with multiple additional patients currently in screening at several activated trial sites.¹ The study was developed through interactions with the FDA under FT819's Regenerative Medicine Advanced Therapy (RMAT) designation and is expected to enroll approximately 53 patients, with enrollment completion anticipated in 15-18 months, by the first half of 2028.¹

How is FT819 administered, and what does the trial measure?

Patients in the RECLAIM-LN trial will receive a single 900 million-cell dose of off-the-shelf FT819 following less-intensive conditioning with bendamustine, with complete renal response at Week 26 serving as the primary endpoint.¹ FT819 is an off-the-shelf, iPSC-derived CD19-targeting chimeric antigen receptor (CAR) T-cell product candidate comprised of CD8αβ+ T cells engineered with a memory phenotype and high CXCR4 expression intended to promote tissue trafficking to affected organs.² Because the therapy is manufactured in advance from a clonal master iPSC line rather than from each patient's own cells, it is designed to be immediately available without the apheresis and patient-specific manufacturing timeline required for autologous CAR T-cell products.³

What did earlier-phase data show?

Preliminary data from the ongoing phase 1 study demonstrated favorable safety and tolerability along with clinically meaningful, sustained improvement across several disease activity measures, including the clinical Systemic Lupus Erythematosus Disease Activity Index and urine protein-to-creatinine ratio.¹ Both measures showed further reductions when patients received less-intensive bendamustine conditioning rather than more intensive regimens.¹ Earlier phase 1 cohorts reported no dose-limiting toxicities and no events of cytokine release syndrome, immune effector-cell associated neurotoxicity syndrome, or graft-versus-host disease, alongside rapid and sustained elimination of CD19-positive B cells in the periphery.²

What did company leadership say?

Bob Valamehr, PhD, MBA, president and chief executive officer of Fate Therapeutics, said, "The initiation of RECLAIM-LN and treatment of the first patient marks an important step in our effort to establish FT819 as a broadly accessible, off-the-shelf CAR T-cell therapy for patients with serious autoimmune disease. The study design reflects our interactions with the FDA under FT819 RMAT designation and builds on the clinical activity, favorable safety profile and patient accessibility observed to date in our Phase 1 program. Early interest from investigators in the lupus nephritis community has been encouraging as we ramp up enrollment."¹

What else supports FT819's regulatory pathway?

FT819 has also been selected for the FDA's Chemistry, Manufacturing, and Controls Development and Readiness Pilot program, which is designed to provide opportunities for early and enhanced communication with the FDA regarding CMC readiness for therapies with accelerated clinical development timelines.¹ The research was additionally supported by a grant from the California Institute for Regenerative Medicine, a state agency funding regenerative medicine, stem cell, and gene therapy research.¹ FT819 is one of two off-the-shelf CAR T-cell candidates Fate is advancing specifically for autoimmune disease; the company's related program, FT839, co-targets CD19 and CD38 and recently received FDA IND clearance for a phase 1/2 basket trial spanning multiple autoimmune conditions without lymphodepleting conditioning chemotherapy.⁴

References

1. Fate Therapeutics initiates potentially registrational RECLAIM-LN clinical trial of FT819 for the treatment of lupus nephritis. News release. Fate Therapeutics, Inc; August 14, 2026. Accessed August 14, 2026.
2. Fate Therapeutics presents new Phase 1 clinical data of FT819 off-the-shelf, CAR T-cell product candidate for systemic lupus erythematosus. News release. Fate Therapeutics, Inc; 2025. Accessed August 14, 2026.
3. Mougiakakos D. Allogeneic CAR T cells for autoimmune diseases: a glimpse into the future. Signal Transduct Target Ther. 2024;9:274. doi:10.1038/s41392-024-01998-8
4. Schoenthaler E. Fate Therapeutics wins FDA IND clearance for FT839, a dual-CAR T-cell therapy for autoimmune disease. BioPharm International. July 2026. Accessed August 14, 2026.