A Comparative Study to Investigate the Difference in Blood Levels of Two Different Formulations of GSK5784283

Open-Label, Randomized, Single Dose, Parallel Group, Phase 1 Study in Healthy Volunteers to Evaluate the Relative Bioavailability of Two Formulations of GSK5784283 Administered by Subcutaneous Injection

The purpose of this study is to compare how two different formulations of the study medicine (GSK5784283) move through the body over time (pharmacokinetic [PK] study) in healthy adults. The aim of the study is to see how the body processes GSK5784283 and determine if the study medicine is safe, how well it is tolerated by the body and if the study medicines being tested work in the body in the same way.

Study Overview

• Status: Not yet recruiting
• Conditions: Asthma
• Intervention / Treatment: Drug: GSK5784283

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: US GSK Clinical Trials Call Center; Phone Number: 877-379-3718; Email: GSKClinicalSupportHD@gsk.com
• Study Contact Backup: Name: EU GSK Clinical Trials Call Center; Phone Number: +44 (0) 20 89904466; Email: GSKClinicalSupportHD@gsk.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Participants who are healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and ECG.
• Body weight greater than or equal (>=) 50 kilogram (kg) (110 pounds [lbs]) and body mass index within the range 19 to 30 kilogram per meter square (kg/m^2) (inclusive).
• A female participant is eligible to participate if she is a participant of non-childbearing potential (PONCBP) as specified in the protocol.
• Capable of giving signed informed consent which includes compliance with the requirements and restrictions listed in the ICF and in this protocol.

Exclusion Criteria:

• Hypersensitivity- Participants with allergy/intolerance to any biologic therapy or any of the known excipients used in products administered subcutaneously
• History or presence of any clinically significant medical condition capable of significantly altering the absorption, metabolism, or elimination of drugs; constituting a risk when taking the study intervention or interfering with the interpretation of data.
• Any clinically relevant abnormal findings in physical examination, hematology, clinical chemistry, urinalysis, vital signs during screening period which in the opinion of the investigator, may put the subject at risk because of his/her participation in the study, or may influence the results of the study, or the subject's ability to participate in the study.
• Live vaccine(s) within 1 month prior to screening or plans to receive such vaccines during the clinical study.
• Treatment with biologic agents (such as monoclonal antibodies including marketed drugs) within 3 months or 5 half-lives (whichever is longer) prior to study intervention administration.
• Current smokers (tobacco and/or marijuana) or former smokers with a smoking history >10 pack-years and participants using vaping products, including electronic cigarettes.
• Regular alcohol consumption that exceeds the limits specified in the protocol
• Sensitivity to any of the study interventions, or components thereof, or drug or other allergy that, in the opinion of the investigator or medical monitor, contraindicates participation in the clinical study.
• The QTc is the QT interval corrected for heart rate according to Fridericia's formula (QTcF), machine-read or manually over-read >450 millisecond (msec).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: GSK5784283 Test Formulation	Drug: GSK5784283; GSK5784283 will be administered.
Experimental: GSK5784283 Reference Formulation	Drug: GSK5784283; GSK5784283 will be administered.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Maximum Observed Concentration (Cmax) of GSK5784283 Serum Samples	Pre-dose and up to 253 days post dose
Area Under the Curve from Zero up to 253 Days [AUC(0-253 d)] of GSK5784283 Serum Samples	Pre-dose and up to 253 days post dose

Secondary Outcome Measures

Outcome Measure	Time Frame
Number of Participants Experiencing Treatment Emergent Adverse Events (TEAEs), Serious AEs and Adverse Event of Special Interest (AESI)	Up to 253 days
Number of Participants with Clinically Significant Change from Baseline in Laboratory Assessments, Vital Signs and Electrocardiogram (ECG) Values	Baseline and up to 253 days
Proportion of Participants with Anti-drug Antibody (ADA) Incidence, ADA Titre Assessment and Neutralizing Antibody (NAb) Incidence Against GSK5784283	Up to 253 days

Collaborators and Investigators

• Sponsor: GlaxoSmithKline
• Investigators: Study Director: GSK Clinical Trials, GlaxoSmithKline

Study record dates

Study Major Dates

• Study Start (Estimated): July 17, 2026
• Primary Completion (Estimated): April 30, 2027
• Study Completion (Estimated): May 3, 2027

Study Registration Dates

• First Submitted: July 14, 2026
• First Submitted That Met QC Criteria: July 14, 2026
• First Posted (Actual): July 17, 2026

Study Record Updates

• Last Update Posted (Actual): July 17, 2026
• Last Update Submitted That Met QC Criteria: July 14, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Healthy volunteers; Safety; Asthma; Pharmacokinetics; Tolerability; GSK5784283
• Additional Relevant MeSH Terms: Immune System Diseases; Respiratory Tract Diseases; Lung Diseases; Bronchial Diseases; Lung Diseases, Obstructive; Respiratory Hypersensitivity; Hypersensitivity, Immediate; Hypersensitivity; Asthma
• Other Study ID Numbers: 307918

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.gsk-studyregister.com/gsk-patient-level-data-sharing-july2025.pdf
• IPD Sharing 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.
• IPD Sharing 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.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No