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COVID-19 Booster Study in Healthy Adults in Australia

Phase 3
Active, not recruiting
Conditions
COVID-19
Interventions
Biological: Novavax
Biological: Bivalent Moderna
Registration Number
NCT05658523
Lead Sponsor
Murdoch Childrens Research Institute
Brief Summary

This is a double-blinded, randomised study to determine the safety, reactogenicity, and immunogenicity of a bivalent mRNA Moderna COVID-19 vaccine or a protein-based Novavax COVID-19 vaccine given as a fourth dose in healthy adults in Australia.

Detailed Description

This is a blinded, two-arm randomised study to determine the safety, reactogenicity and immunogenicity of a fourth dose of SARS-CoV-2 vaccines in Australia in adults 18 years or older who have received their third dose of COVID-19 vaccine at least six months previously. Participants will be randomised to receive either bivalent Moderna (mRNA-1273.214) or Novavax. A separate non-randomised control arm (no vaccine given), frequency matched by age to the vaccine groups will also be enrolled for comparison. A total of 200 participants per group will be recruited.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
497
Inclusion Criteria
  1. Have received three doses of COVID-19 vaccines at least 6 months earlier.
  2. No confirmed SARS-CoV-2 infection on PCR or RAT within the last 3 months.
  3. Willing and able to give written informed consent.
  4. Aged 18 years or above.
  5. Willing to complete the follow-up requirements of the study.
Exclusion Criteria
  1. Currently receiving immunosuppressive medication or anti-cancer chemotherapy.
  2. Known HIV infection.
  3. Congenital immune deficiency syndrome.
  4. Received immunoglobulin or other blood products in the three months prior to potential study booster vaccination.
  5. Study staff and their relatives.
  6. Have a history of a severe allergic reaction to any COVID-19 vaccines or have a medical exemption to receiving further COVID-19 vaccines.
  7. Cannot read or understand English.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
NovavaxNovavaxParticipants who have received three doses of COVID-19 vaccine, with the last dose at least 6 months prior to the study, will receive a booster dose of Novavax COVID-19 protein subunit vaccine. Novavax contains 5μg of SARS-CoV-2 spike protein and is adjuvanted with Matrix-M. Adjuvant Matrix-M contains, per 0.5 mL dose: Quillaja saponaria saponins fraction A (42.5 micrograms) and Quillaja saponaria saponins fraction C (7.5 micrograms).
Bivalent Moderna (mRNA-1273.214)Bivalent ModernaParticipants who have received three doses of COVID-19 vaccine, with the last dose at least 6 months prior to the study, will receive a booster dose of bivalent mRNA Moderna COVID-19 vaccine (mRNA-1273.214) The mRNA-1273.214 encodes the prefusion stabilized S protein of SARS-CoV-2 formulated in RNA-lipid nanoparticles composed of 4 lipids and 1-monomethoxypolyethyleneglycol-2, 3-dimyristylglycerol with polyethylene glycol. 25μg of each mRNA sequence that encode the prefusion stabilized spike glycoproteins of the ancestral SARS-CoV-2 (Wuhan-Hu-1) and the Omicron variant (B.1.1.529 \[BA.1\]).
Primary Outcome Measures
NameTimeMethod
SARS-CoV-2 specific Immunoglobulin (Ig)G antibodies at 28-days post booster vaccination28-days post booster vaccination

Serum samples collected at 28-days post booster vaccination from the two intervention groups will be evaluated for SARS-CoV-2 specific IgG antibodies using the commercial Euroimmun S1 IgG ELISA. Data will be reported as binding antibody units/mL and presented as geometric mean concentration and 95% confidence intervals

Total incidence of solicited reactions (systemic and local)Total incidence of solicited reactions will be measured for 7 days post booster vaccination

Questionnaire to document solicited reactions is developed specifically for this study. Data will be reported as the proportion of participants who report by each intervention arm. Solicited reactions such as pain, tenderness, erythema/redness, induration/swelling, fever, nausea/vomiting, headache, fatigue/malaise, myalgia, arthralgia will be collected from the participants 7 days post-vaccination.

Secondary Outcome Measures
NameTimeMethod
Frequency of cytokine-expressing T cellsBaseline (pre booster), 6-months and 12-months post booster vaccination

Frequency of cytokine-expressing T cells will be assessed on a subset (50%) of participants using Flow cytometry (intracellular staining) on PBMCs samples stimulated with SARS-CoV-2 specific peptides. Data will be reported as frequency (%) of cytokine-expressing T cells presented as means and 95% CI.

Cytokine concentrations following PBMCs stimulationBaseline (pre booster), 6-months and 12-months post booster vaccination

Cytokine concentrations following PBMCs stimulation will be assessed on a subset (50%) of participants using multiplex cytokine assays. Data will be reported as cytokine concentrations in pg/ml and presented as GMC and 95% CI.

SARS-CoV-2 specific IgG antibodies at baseline (pre booster), and 6- and 12-months post booster vaccinationBaseline (pre booster), 6-months and 12-months post booster vaccination

Serum samples collected at baseline (pre booster), 6- and 12-months post booster vaccination from the two intervention groups and the control group will be evaluated for SARS-CoV-2 specific IgG antibodies using the commercial Euroimmun S1 IgG ELISA . Data will be reported as binding antibody units/mL and presented as geometric mean concentration and 95% confidence intervals

Number of IFNγ producing cells/million PBMCsBaseline (pre booster), 6-months and 12-months post booster vaccination

IFNγ producing cells as a measurement of cellular immunity will be assessed on a subset (50%) of the participants from each group. IFN-γ Enzyme-Linked ImmunoSpot (Elispot) assay will be performed on isolated peripheral blood mononuclear cells (PBMCs) stimulated with SARS-CoV-2 specific peptides. Data will be reported as number of IFNγ producing cells/million and presented using means and 95% confidence intervals.

Incidence of serious adverse events (SAE)12 months post booster vaccination

SAE will be collected throughout the follow-up period of 12 months post booster vaccination. Data will be presented as a proportion of participants who report unsolicited SAE.

SARS-CoV-2 specific neutralising antibodies at baseline (pre booster), 28 days and 6- months post booster vaccination measured by SARS-CoV-2 microneutralisation assayBaseline (pre booster), 6-months and 12-months post booster vaccination

A subset of samples (20%) from all timepoints will be assessed using a SARS-CoV-2 microneutralisation assay to both the wild type (vaccine) strain and for two SARS-CoV-2 Variants of concern. Neutralizing antibody will be reported as endpoint titre.

SARS-CoV-2 specific neutralising antibodies at baseline (pre booster), 28 days, 6- and 12-months post booster vaccination measured by surrogate virus neutralization test (sVNT)Baseline (pre booster), 6-months and 12-months post booster vaccination

Serum samples collected at baseline (pre booster), 28 days, 6- and 12-months post booster vaccination from all groups will be evaluated for SARS-CoV-2 specific neutralising antibodies using the GenScript® cPass surrogate virus neutralization test (sVNT) for both wild-type and Omicron variant. Neutralising antibody response will be reported as percentage (%) inhibition of receptor binding domain-angiotensin-converting enzyme 2 (RBD-ACE2) binding relative to a positive control.

Interferon gamma (IFNγ) concentrations in International Units (IU)/mLBaseline (pre booster), 6-months and 12-months post booster vaccination

Interferon gamma (IFNγ) concentrations as a measurement of cellular immunity will be assessed on a subset (50%) of the participants from each group. QuantiFERON Human IFN-γ SARS-CoV-2 (Qiagen) will be used to stimulate IFN-γ production in whole blood and then IFN-γ production will be measured using Enzyme-Linked ImmunoSorbent Assay (ELISA). Data will be presented as geometric mean concentration (GMC) and 95% confidence intervals (CI).

Incidence of unsolicited adverse events (AE)28 days-post booster vaccination

All unsolicited AE will be collected for 28 days post booster vaccination. Data will be presented as proportion of participants who report unsolicited AE.

Incidence of medically attended adverse events (AE)3 months post booster vaccination

Participants with medically attended AE will be collected for 3 months post booster vaccination. Data will be presented as proportion of participants who report unsolicited AE.

Trial Locations

Locations (1)

Royal Children's Hospital, Murdoch Children's Research Institute

🇦🇺

Melbourne, Victoria, Australia

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