A Study of GSK5926371 in Participants With B-cell Driven Autoimmune Rheumatic Diseases (ARD)

NCT07371468 | Recruiting Phase 1 FDA Drug

• 2 other identifiers: 3001342025-522932-15-00
• Study Type: interventional
• Target: 54
• Locations: 1 country
• Sites: 3

Brief Summary

This is a 2-part study of GSK5926371 in participants with autoimmune rheumatic diseases (ARD). In part 1, participants will receive different doses of GSK5926371 to find a suitable priming dose. In part 2, participants will receive GSK5926371 at doses based on data from part 1. The study is aimed at testing if GSK5926371 is safe, well-tolerated, how the body processes the study drug, how it works in the body, and whether it triggers any immune responses.

Conditions

Systemic Lupus Erythematosus

Keywords

GSK5926371; Autoimmune rheumatic disease; Dose escalation; Systemic lupus erythematosus; Rheumatoid arthritis; Idiopathic inflammatory myopathies; Sjogren's disease

Outcome Measures

Primary Outcomes (1)

• Part 1 and Part 2: Number of Participants with Adverse Events (AEs) and Serious AEs (SAEs)

  Up to 196 days

Secondary Outcomes (12)

• Part 1: Maximum Observed Plasma Concentration (Cmax) After GSK5926371 Dosing

  Up to 43 days

• Part 2: Cmax After GSK5926371 Dosing

  Up to 113 days

• Part 1 and Part 2: Number of Participants with Anti-drug Antibodies (ADAs) Against GSK5926371

  Up to 196 days

• Part 1 and Part 2: Titers of ADAs Against GSK5926371

  Up to 196 days

• Part 1: Absolute B-cell and T-cell Counts in Blood

  Up to 57 days

Study Arms (2)

Part 1: Dose Escalation of GSK5926371

EXPERIMENTAL

Biological: GSK5926371

Part 2: Dose Division of GSK5926371

EXPERIMENTAL

Biological: GSK5926371

Interventions

GSK5926371 BIOLOGICAL

GSK5926371 will be administered.

Part 1: Dose Escalation of GSK5926371; Part 2: Dose Division of GSK5926371

Eligibility Criteria

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

You may qualify if:

• Part 1 will enroll adult participants with systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA).
• Part 2 will enroll adult participants with SLE, RA, idiopathic inflammatory myopathies (IIM) or Sjogren's disease (SjD).
• Participants must be 18 to 70 years of age inclusive at the time of signing the informed consent form.
• Body mass index (BMI) between 18-35 kilograms per square meter (kg/m\^2) inclusive with a body weight of greater than or equal to (\>=) 45 kilograms (kg).
• A female participant is eligible to participate if she is not pregnant or breastfeeding, and one of the following conditions applies:
• Is a participant of non-childbearing potential (PONCBP), OR
• Is a participant of childbearing potential (POCBP) and using a contraceptive method that is highly effective, with a failure rate of less than (\<) 1 percent (%), 28 days prior to and during the study intervention period and for at least 28 weeks after the first dose of GSK5926371. The investigator should evaluate potential for contraceptive method failure (e.g. noncompliance, recently initiated) in relationship to the first dose of study intervention.
• A POCBP must have a negative highly sensitive pregnancy test (urine or serum, as required by local regulations) within 24 hours before the first dose of study intervention.
• If a urine test cannot be confirmed as negative (e.g. an ambiguous result), a serum pregnancy test is required. In such cases, the participant must be excluded from participation if the serum pregnancy result is positive.
• \- Signed and dated informed consent form indicating that the participant is willing and able to comply with hospitalization, clinic visits and scheduled study assessments as detailed in the protocol.

You may not qualify if:

• Any acute, severe autoimmune disease-related flare before, or during the Screening Period (up to and including Day 1) that needs immediate treatment or is expected to require escalation of treatment to prohibited medications for the duration of the study.
• Significant allergies to humanized monoclonal antibodies or significant sensitivity to any constituents of the study drug (including excipients).
• Clinically significant multiple or severe drug allergies, intolerance to topical corticosteroids, or severe post-treatment hypersensitivity reactions (including, but not limited to, erythema multiforme major, linear immunoglobulin A (IgA) dermatosis, toxic epidermal necrolysis, and exfoliative dermatitis).
• Have clinical evidence of significant unstable or uncontrolled acute or chronic diseases not due to the autoimmune condition under study (i.e., cardiovascular, pulmonary, hematologic, gastrointestinal, hepatic, renal, or infectious diseases) and/or a planned surgical procedure, which, in the opinion of the investigator, could confound the results of the clinical study or put the participant at undue risk.
• Have any other clinically significant abnormal laboratory value, that in the opinion of the investigator, is capable of significantly altering the absorption, metabolism, or elimination of the clinical study intervention; or constitutes a risk when taking the clinical study intervention or interferes with the interpretation of the clinical study data.
• Participant has a diagnosis of primary or acquired immunodeficiency, except for selective IgA deficiency.
• Have an acute or chronic infection including requiring management as follows:
• An acute infection within 2 weeks of dosing on Day 1.
• An active infection requiring current systemic antibiotic, antiviral or anti-fungal treatment with the exception of topical treatments for fungal nail infections. Prophylactic medications are permitted.
• History of, or currently being treated for, a clinically significant recurrent or chronic infection (except for minor localized infections, for example tinea pedis).
• Any opportunistic infections within past 3 years. Uncomplicated herpes zoster, localized herpes simplex virus, and oral candidiasis are not considered as opportunistic infections for this purpose.
• Herpes zoster within 3 months before screening.
• A serious infection requiring treatment with intravenous (IV)/intramuscular (IM) antibiotics and/or hospitalization if the last dose of antibiotics or the hospital discharge date was within 30 days of the first day of dosing (Day 1).
• History of a serious infection associated with low serum immunoglobulin levels.
• Evidence of active or latent tuberculosis (TB) as documented by medical history and examination (including chest X-rays \[CXR\], if available), and a positive (not indeterminate) TB test such as QuantiFERON-TB Gold Plus test. In cases where the QuantiFERON test is indeterminate, the participant may have the test repeated once, but if the test remains indeterminate further investigation may be required including CXR (posteroanterior \[PA\] and lateral) in order to exclude TB. Note: The QuantiFERON-TB Gold Plus test can only be used in countries where it is licensed, and the use of this test is dependent on previous treatment(s). This test may not be suitable if previous treatment(s) produced significant immunosuppression.

Sponsors & Collaborators

• GlaxoSmithKline: lead

Study Sites (3)

GSK Investigational Site

Fukuoka, 812-8582, Japan

RECRUITING

GSK Investigational Site

Hiroshima, 734-8551, Japan

RECRUITING

GSK Investigational Site

Hokkaido, 060-8648, Japan

RECRUITING

MeSH Terms

Conditions

Lupus Erythematosus, Systemic; Arthritis, Rheumatoid; Myositis; Sjogren's Syndrome

Condition Hierarchy (Ancestors)

Connective Tissue Diseases; Skin and Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Muscular Diseases; Neuromuscular Diseases; Nervous System Diseases; Xerostomia; Salivary Gland Diseases; Mouth Diseases; Stomatognathic Diseases; Dry Eye Syndromes; Lacrimal Apparatus Diseases; Eye Diseases

Study Officials

• GSK Clinical Trials

  GlaxoSmithKline

  STUDY DIRECTOR

Central Study Contacts

US GSK Clinical Trials Call Center

CONTACT

877-379-3718; GSKClinicalSupportHD@gsk.com

EU GSK Clinical Trials Call Center

CONTACT

+44 (0) 20 89904466; GSKClinicalSupportHD@gsk.com

Study Design

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

Study Record Dates

• First Submitted: January 19, 2026
• First Posted: January 28, 2026
• Study Start: February 10, 2026
• Primary Completion (Estimated): March 15, 2028
• Study Completion (Estimated): March 15, 2028
• Last Updated: March 17, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or asset(s) with development terminated across all indications.
• Access Criteria: Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months, but an extension may be granted, when justified, for up to 6 months.

Locations

JP (3)