A Study to Evaluate Safety, Reactogenicity, and Immunogenicity of the GSK 4-component Strep A Vaccine With Aluminum Hydroxide (Alum) or AS37 in Healthy Young Adults

NCT07085702 | Recruiting Phase 1 DMC

• 4 other identifiers: 21793575A50122C00028224842/Z/21/Z2-28-23
• Study Type: interventional
• Target: 108
• Locations: 1 country
• Sites: 2

Brief Summary

The purpose of this study is to assess the safety of 3 doses of 2 new Strep A vaccine formulations, one with an Alum adjuvant, and the other with AS37 adjuvant. The Strep A vaccine will be tested for the first time in humans, in healthy young adults 18 to 25 years of age. The study will also assess if the vaccines have any immediate reactions and if they induce an immune response. A low, medium, and high dose of each formulation of the vaccine will be assessed in sequence.

Conditions

Streptococcal Infections

Keywords

Strep A; Streptococcus pyogenes; Safety; Reactogenicity; Immunogenicity; Healthy Adults; Australia

Outcome Measures

Primary Outcomes (7)

• Number of participants with solicited administration site events

  Solicited administration-site events include pain, redness, and swelling at the administration site.

  Up to 7 days after each study intervention administration occurring at Day 1, Day 31, and Day 121

• Number of participants with solicited systemic events

  Solicited systemic events include fever, headache, myalgia (muscle pain), arthralgia (joint pain), and fatigue (tiredness). Fever is defined as body temperature equal to or above 38.0°C. The preferred location for measuring temperature is the axilla.

  Up to 7 days after each study intervention administration occurring at Day 1, Day 31, and Day 121

• Number of participants with unsolicited adverse events (AEs)

  An unsolicited AE is an AE that was either not included in the list of solicited events or could be included in the list of solicited events but with an onset outside the specified period of follow-up for solicited events. Unsolicited AEs include both serious and nonserious AEs.

  Up to 30 days after each study intervention administration occurring at Day 1, Day 31, and Day 121

• Number of participants with laboratory abnormalities

  7 days after each study intervention administration at Day 8, Day 38, and Day 128

• Number of participants with adverse events of special interest (AESIs)

  AESIs include potential immune-mediated disorders (pIMDs) and rheumatic carditis.

  From Day 1 to Day 301

• Number of participants with serious adverse events (SAEs)

  An SAE is defined as any untoward medical occurrence that results in death, is life threatening, requires hospitalization or prolongs existing hospitalization, results in disability/incapacity, abnormal pregnancy outcomes, or other medically significant events.

  From Day 1 to Day 301

• Number of participants with AEs leading to withdrawal from the study or to discontinuation of study vaccine

  From Day 1 to Day 301

Secondary Outcomes (3)

• Geometric mean concentrations of immunoglobulin G (IgG) against Streptolysin O (SLO), S. pyogenes Cell Envelope Protease (SpyCEP), S. pyogenes Adhesion and Division protein (SpyAD), and Group A Carbohydrate (GAC), as measured by multiplex immunoassay

  Before each study intervention (Day 1, Day 31, and Day 121), 30 days after each study intervention (Day 31, Day 61, and Day 151), and 7 days and 6 months after the third study intervention administration (Days 128 and 301, respectively)

• Geometric mean fold increase of IgG against SLO, SpyCEP, SpyAD, and GAC, as measured by multiplex immunoassay

  30 days after each study intervention administration compared to before each study intervention administration (Day 31 versus Day 1, Day 61 versus Day 31, and Day 151 versus Day 121) and to before study intervention administration (Day 1)

• Number of participants with greater than or equal to (>=) 2-fold and >=4 fold increase in IgG antibody concentration against SLO, SpyCEP, SpyAD, and GAC, as measured by multiplex immunoassay

  30 days after each study intervention administration (Day 31, Day 61, and Day 151) compared to before study intervention administration (Day 1)

Study Arms (7)

Low dose Strep A Alum Group

EXPERIMENTAL

Participants randomized to receive 3 doses of Low dose Strep A Alum vaccine on Day 1, Day 31, and Day 121.

Biological: Low dose Strep A Alum

Medium dose Strep A Alum Group

EXPERIMENTAL

Participants randomized to receive 3 doses of Medium dose Strep A Alum vaccine on Day 1, Day 31, and Day 121.

Biological: Medium dose Strep A Alum

High dose Strep A Alum Group

EXPERIMENTAL

Participants randomized to receive 3 doses of High dose Strep A Alum vaccine on Day 1, Day 31, and Day 121.

Biological: High dose Strep A Alum

Low dose Strep A AS37 Group

EXPERIMENTAL

Participants randomized to receive 3 doses of Low dose Strep A AS37 vaccine on Day 1, Day 31, and Day 121.

Biological: Low dose Strep A AS37

Medium dose Strep A AS37 Group

EXPERIMENTAL

Participants randomized to receive 3 doses of Medium dose Strep A AS37 vaccine on Day 1, Day 31, and Day 121.

Biological: Medium dose Strep A AS37

High dose Strep A AS37 Group

EXPERIMENTAL

Participants randomized to receive 3 doses of High dose Strep A AS37 vaccine on Day 1, Day 31, and Day 121.

Biological: High dose Strep A AS37

Strep A Alum Placebo Group

PLACEBO COMPARATOR

Participants randomized to receive 3 doses of Strep A Alum Placebo on Day 1, Day 31, and Day 121.

Drug: Strep A Alum Placebo

Interventions

Low dose Strep A Alum BIOLOGICAL

Low dose Strep A Alum vaccine will be administered intramuscularly (IM)

Low dose Strep A Alum Group

Medium dose Strep A Alum BIOLOGICAL

Medium dose Strep A Alum vaccine will be administered IM

Medium dose Strep A Alum Group

High dose Strep A Alum BIOLOGICAL

High dose Strep A Alum vaccine will be administered IM

High dose Strep A Alum Group

Low dose Strep A AS37 BIOLOGICAL

Low dose Strep A AS37 vaccine will be administered IM

Low dose Strep A AS37 Group

Medium dose Strep A AS37 BIOLOGICAL

Medium dose Strep A AS37 vaccine will be administered IM

Medium dose Strep A AS37 Group

High dose Strep A AS37 BIOLOGICAL

High dose Strep A AS37 vaccine will be administered IM

High dose Strep A AS37 Group

Strep A Alum Placebo DRUG

Strep A Alum Placebo will be administered IM

Strep A Alum Placebo Group

Eligibility Criteria

• Age: 18 Years - 25 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Participants, who, in the opinion of the Investigator, can and will comply with the requirements of the protocol (e.g., completion of electronic diaries \[eDiaries\], return for follow-up visits).
• Written or witnessed/thumb-printed informed consent obtained from the participant prior to performance of any study-specific procedure.
• Healthy participants as established by medical history, clinical examination, and laboratory assessments.
• Satisfies all screening requirements.
• Male and female participants between and including 18 and 25 years of age at the time of informed consent.
• Female participants of nonchildbearing potential may be enrolled in the study. Nonchildbearing potential is defined as premenarche, postmenopause, or had current bilateral tubal ligation or occlusion, hysterectomy, or bilateral ovariectomy.
• Female participants who are of childbearing potential may be enrolled in the study if the participant:
• has practiced adequate contraception for 1 month prior to study intervention administration, and
• has a negative pregnancy test on the day of study intervention administration, and
• has agreed to continue adequate contraception during the entire study intervention administration period and for 1 month after completion of the study intervention administration series.
• Male participants who are sexually active with a female partner of childbearing potential are eligible to participate if they agree to have their partner use a highly effective method of contraception for 1 month prior to the first study intervention administration until 1 month after completion of the study intervention administration series.
• Male participants must refrain from donating sperm for 1 month prior to the first study intervention administration until 1 month after completion of the study intervention administration series.
• Participants seronegative for human immunodeficiency virus (HIV), hepatitis B, and hepatitis C at Screening.

You may not qualify if:

• History of rheumatic fever or rheumatic heart disease during the lifetime of the participant as confirmed during interview with the participant or as documented in medical records.
• Recent history of pharyngitis in the last four (4) weeks will be excluded. These participants can be rescreened once the recent pharyngitis passes the 4-weeks period. Participants with symptoms of acute pharyngitis at Screening will be tested with a Strep A rapid antigen test. Those with positive results will be excluded.
• Progressive, unstable, or uncontrolled clinical conditions.
• History (known or suspected) of any reaction or hypersensitivity likely to be exacerbated by any component of the study interventions.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
• Hypersensitivity (e.g., allergy) to medicinal products or medical equipment anticipated to be used in this study.
• Clinical conditions that represents a contraindication for IM vaccination or blood draws.
• Any behavioral or cognitive impairment or psychiatric disease that, in the opinion of the Investigator, may interfere with the participant's ability to participate in the study.
• Acute disease and/or fever (defined as temperature \>=38.0°C) at the time of enrollment.
• Any Grade \>=2 and/or clinically significant hematological and/or biochemical laboratory abnormality.
• Any echocardiographic/Doppler Echo findings consistent with carditis at Screening.
• Recurrent history or uncontrolled neurological disorders or seizures.
• Medical history or family history of autoimmune disease and other pIMDs.
• Family history of acute rheumatic fever.
• Acute or chronic illness, or clinically significant pulmonary, cardiovascular, hepatic, or renal functional abnormality.

Sponsors & Collaborators

• GlaxoSmithKline: lead
• HHS/BARDA: collaborator
• Wellcome Trust: collaborator
• DHSC/GAMRIF: collaborator
• Germany/BMBF: collaborator

Study Sites (2)

GSK Investigational Site

Botany, New South Wales, 2019, Australia

RECRUITING

GSK Investigational Site

Camberwell, Victoria, 3124, Australia

RECRUITING

MeSH Terms

Conditions

Streptococcal Infections

Condition Hierarchy (Ancestors)

Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Infections

Study Officials

• King C Cheung

  Emeritus Research

  PRINCIPAL INVESTIGATOR

• Juliet Freeborn

  Emeritus Research

  PRINCIPAL INVESTIGATOR

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: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Observer-blinded
• Purpose: PREVENTION
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 11, 2025
• First Posted: July 25, 2025
• Study Start: July 31, 2025
• Primary Completion (Estimated): November 30, 2026
• Study Completion (Estimated): November 30, 2026
• Last Updated: August 11, 2025

Record last verified: 2025-08

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 terminated asset(s) 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

AU (2)