Fate Therapeutics Shares 6-Month Data on First Patient in Phase 1 Autoimmunity Study with FT819 at ACR Convergence

Fate Therapeutics, Inc., a clinical-stage biopharmaceutical company, recently showcased promising results from their FT819 Phase 1 Autoimmunity study for systemic lupus erythematosus (SLE) at the American College of Rheumatology (ACR) Convergence in Washington, D.C. The first patient in this study, a 27-year-old African American-Asian woman with active lupus nephritis (LN), achieved notable clinical remission. Diagnosed over ten years ago, she was treated with fludarabine-free conditioning and a single dose of FT819, an off-the-shelf, CD19-targeted CAR T-cell product.

By Month 6, the patient reached DORIS clinical remission and low lupus disease activity state (LLDAS). She continues to be in clinical remission and free of all immunosuppressive therapies as of November 11, 2024. FT819 is distinguished by its CD8αβ+ T cells with a memory phenotype and high CXCR4 expression, enhancing tissue trafficking capabilities. Jennifer Medlin, M.D., University of Nebraska Medical Center, praised the study’s initial outcomes, stating that the patient not only achieved drug-free clinical remission but also experienced significant improvement in fatigue, a challenging symptom to manage in lupus treatments. If these results persist in other patients, this off-the-shelf CAR T-cell therapy could significantly impact lupus treatment.

The first patient had severe LN, marked by high disease activity scores and debilitating fatigue. After receiving fludarabine-free conditioning and FT819 at 360 million cells, she was discharged from the hospital without notable adverse events. By the data cutoff, she had no severe adverse events (AEs) and no incidents of cytokine release syndrome (CRS), immune effector-cell associated neurotoxicity syndrome (ICANS), or graft-versus-host disease (GvHD). Her fatigue resolved entirely without further treatment, and she discontinued methylprednisolone by Month 3. By Month 6, she had achieved clinical remission, with resolved arthritis, active urinary sediment, and significantly reduced proteinuria. She continues in clinical remission without immunosuppressive therapy.

Following treatment, there was a rapid elimination of CD19+ B cells. By Month 3, B-cell recovery was predominantly naïve, non-class switched B cells, indicating an immune reset. Notably, the unique double-negative (DN) B-cell subset associated with severe SLE was nearly eliminated.

Scott Wolchko, President and CEO of Fate Therapeutics, expressed optimism about the initial success with FT819, emphasizing its potential to transform outcomes for autoimmune disease patients. The FT819 Phase 1 Autoimmunity study is ongoing, evaluating the safety, pharmacokinetics, and anti-B cell activity of FT819. Three initial patients with active LN received fludarabine-free conditioning and FT819. All remain on-study without dose-limiting toxicities (DLTs) or adverse events like CRS, ICANS, or GvHD. Fate Therapeutics plans to present additional data at the American Society of Hematology (ASH) Annual Meeting in December.

A second treatment arm has been introduced to assess the safety and activity of FT819 as an add-on to maintenance therapy without conditioning chemotherapy in SLE patients. This new arm runs parallel to the conditioning arm in the study.

Fate Therapeutics leverages human induced pluripotent stem cells (iPSCs) for their unique dual properties of unlimited self-renewal and differentiation potential, creating engineered cell products for off-the-shelf availability. Their iPSC product platform, supported by over 500 patents and applications, aims to overcome the limitations of patient- or donor-sourced cell therapies. Fate Therapeutics, headquartered in San Diego, is committed to advancing its iPSC-derived cellular immunotherapies for cancer and autoimmune diseases.