Recruiting
Phase 1
Phase 2

FT839 & Rituximab

Sponsor:

Fate Therapeutics

Code:

NCT07800871

Conditions

ANCA-Associated Vasculitis (AAV)

Idiopathic Inflammatory Myositis (IIM)

Rheumatoid Arthritis (RA)

Systemic Lupus Erythematosus (SLE)

Systemic Sclerosis (SSc)

Eligibility Criteria

Sex: All

Age: 18 - 70

Healthy Volunteers: Not accepted

Interventions

FT839

Study Details

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)

Study ID

NCT07800871

Start date

Oct, 2026

Status verified date

Sep, 2026

Completion date

Oct, 2040

Anticipated

Primary completion date

Oct, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 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

Exclusion Criteria:

  • 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

Study Design

Enrollment

446 participants

Anticipated

Allocation

Non randomized

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: FT839 + Rituximab (Regimen A)

FT839, allogeneic T cells targeting CD19 and CD38

experimental: FT839 + Rituximab with stable background therapy (Regimen B)

FT839, allogeneic T cells targeting CD19 and CD38

experimental: FT839 monotherapy (Regimen C)

FT839, allogeneic T cells targeting CD19 and CD38

experimental: FT839 with stable background therapy (Regimen D)

FT839, allogeneic T cells targeting CD19 and CD38

experimental: Conditioning + FT839 + Rituximab (Regimen E)

FT839, allogeneic T cells targeting CD19 and CD38

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

FT839, allogeneic T cells targeting CD19 and CD38

experimental: Conditioning + FT839 (Regimen G)

FT839, allogeneic T cells targeting CD19 and CD38

experimental: Conditioning + FT839 with stable background therapy (Regimen H)

FT839, allogeneic T cells targeting CD19 and CD38

Interventions

FT839

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

Primary outcome measure

  • Phase 1: Incidence of Dose-limiting Toxicity, Adverse Events, and Serious Adverse Events [ Time Frame: From enrollment to the end of the post-treatment follow-up at 2 years ]
  • Phase 2: Change from baseline in Birmingham Vasculitis Activity Score [ Time Frame: From enrollment to the end of the post-treatment follow-up at 2 years ]
  • Phase 2: Change from baseline in Manual muscle testing-8 [ Time Frame: 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) [ Time Frame: 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 [ Time Frame: From enrollment to the end of the post-treatment follow-up at 2 years ]
  • Phase 2: Change from baseline in Modified Rodnan skin score [ Time Frame: From enrollment to the end of the post-treatment follow-up at 2 years ]

Central Contacts and Locations

Central contacts

Fate Clinical Trials

858-875-1800clinicaltrials@fatetherapeutics.com

Locations

Providence Medical Foundation

Recruiting

Fullerton, California, United States, 92835

More Information

Sponsor

Fate Therapeutics

Last update posted

Sep 2, 2026

Last verified

Sep, 2026

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

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Fate Therapeutics on 2026-09-02.