FT839 in Autoimmune Diseases

NCT07800871 | Recruiting Phase 1 DMC FDA Drug

• 1 other identifier: FT839-101
• Study Type: interventional
• Target: 446
• Locations: 1 country
• Sites: 1

Brief Summary

The primary objectives of this trial are to evaluate the safety and tolerability and to determine the maximum tolerated dose (MTD) or recommended Phase 2 dose of FT839 with or without rituximab and/or background therapy and/or conditioning therapy.

Conditions

ANCA-Associated Vasculitis (AAV); Idiopathic Inflammatory Myositis (IIM); Rheumatoid Arthritis (RA); Systemic Lupus Erythematosus (SLE); Systemic Sclerosis (SSc)

Keywords

FT839; Fate Therapeutics; Allogenic CAR T; CD19 - targeted therapy; CD38 - targeted therapy; ANCA-associated vasculitis; Rheumatoid arthritis; Systemic sclerosis; Idiopathic inflammatory myositis; Dermatomyositis; Polymyositis

Outcome Measures

Primary Outcomes (6)

• Phase 1: Incidence of Dose-limiting Toxicity, Adverse Events, and Serious Adverse Events

  Incidence and severity of dose-limiting Toxicity (DLT)s, adverse event (AE)s, and serious adverse event (SAE)s

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Change from baseline in Birmingham Vasculitis Activity Score

  Birmingham Vasculitis Activity Score (BVAS) will be measured to evaluate the efficacy of FT839 in AAV. The BVAS score ranges from 0 to 63, with lower scores indicating better outcomes.

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Change from baseline in Manual muscle testing-8

  Manual muscle testing-8 (MMT-8) will be measured to evaluate the efficacy of FT839 in IIM. The MMT-8 score ranges from 0 to 150, with higher scores indicating better outcomes.

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Change from baseline in Disease Activity Score using 28 joint counts and C-reactive protein (a composite measure)

  Disease Activity Score using 28 joint counts and C-reactive protein (DAS28-CRP) will be measured to evaluate the efficacy of FT839 in RA. The validated composite measure DAS28-CRP score ranges from 0.0 to 9.4, with lower scores indicating better outcomes.

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Change from baseline in SLE Disease Activity Index 2000

  SLE Disease Activity Index 2000 (SLEDAI-2K) score will be measured to evaluate the efficacy of FT839 in SLE. The SLEDAI-2K score ranges from 0 to 105, with lower scores indicating better outcomes.

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Change from baseline in Modified Rodnan skin score

  Modified Rodnan skin (mRSS) score will be measured to evaluate the efficacy of FT839 in SSc. The mRSS score ranges from 0 to 51, with lower scores indicating better outcomes.

  From enrollment to the end of the post-treatment follow-up at 2 years

Secondary Outcomes (4)

• Phase 1: Maximum concentration and area under the curve of FT839 in peripheral blood

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Incidence of AEs and SAEs

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: Cmax of FT839 in peripheral blood

  From enrollment to the end of the post-treatment follow-up at 2 years

• Phase 2: AUC of FT839 in peripheral blood

  From enrollment to the end of the post-treatment follow-up at 2 years

Study Arms (8)

FT839 + Rituximab (Regimen A)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

FT839 + Rituximab with stable background therapy (Regimen B)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

FT839 monotherapy (Regimen C)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

FT839 with stable background therapy (Regimen D)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

Conditioning + FT839 + Rituximab (Regimen E)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

Conditioning + FT839 + Rituximab with stable background therapy (Regimen F)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

Conditioning + FT839 (Regimen G)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

Conditioning + FT839 with stable background therapy (Regimen H)

EXPERIMENTAL

FT839, allogeneic T cells targeting CD19 and CD38

Biological: FT839

Interventions

FT839 BIOLOGICAL

Single Intravenous (IV) infusion of FT839 administered on Day 1 and Day 4

Conditioning + FT839 (Regimen G); Conditioning + FT839 + Rituximab (Regimen E); Conditioning + FT839 + Rituximab with stable background therapy (Regimen F); Conditioning + FT839 with stable background therapy (Regimen H); FT839 + Rituximab (Regimen A); FT839 + Rituximab with stable background therapy (Regimen B); FT839 monotherapy (Regimen C); FT839 with stable background therapy (Regimen D)

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 to ≤70 years
• Must have active B-cell mediated autoimmune disease (AAV, IIM, RA, SLE, or SSc) confirmed by standard criteria
• Moderate to severe disease, requiring at least two prior treatments that were ineffective
• Adequate organ function to tolerate treatment
• Able to provide informed consent and comply with study procedures

You may not qualify if:

• Diagnosis of more than 1 disease under study (AAV, IIM, RA, SSc, or SLE) or overlap syndrome
• Women must not be pregnant or nursing
• Severe Organ Dysfunction: Significant heart, lung, liver, or kidney impairment.
• Active or chronic infections
• Active or recent malignancies
• Prior CAR T-cell therapy or organ transplantation
• Known allergies to study treatments
• Body weight \<45 kg
• Active central nervous system (CNS) symptoms attributable to autoimmune disease or nonmalignant CNS disease within 12 months prior to trial intervention
• Receipt of any anti-CD19- or anti-CD20-directed therapy within 6 months prior to trial intervention

Sponsors & Collaborators

• Fate Therapeutics: lead

Study Sites (1)

Providence Medical Foundation

Fullerton, California, 92835, United States

RECRUITING

MeSH Terms

Conditions

Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis; Myositis; Arthritis, Rheumatoid; Lupus Erythematosus, Systemic; Scleroderma, Systemic; Dermatomyositis; Polymyositis

Condition Hierarchy (Ancestors)

Systemic Vasculitis; Vasculitis; Vascular Diseases; Cardiovascular Diseases; Skin Diseases, Vascular; Skin Diseases; Skin and Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases; Muscular Diseases; Musculoskeletal Diseases; Neuromuscular Diseases; Nervous System Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Connective Tissue Diseases

Central Study Contacts

Fate Clinical Trials

CONTACT

858-875-1800; clinicaltrials@fatetherapeutics.com

Natalie Shiff, MD

CONTACT

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 24, 2026
• First Posted: September 2, 2026
• Study Start: October 1, 2026
• Primary Completion (Estimated): October 1, 2028
• Study Completion (Estimated): October 1, 2040
• Last Updated: September 2, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)