Evaluation of Full Versus Fractional Doses of COVID-19 Vaccines Given as a Booster in Adults in Australia - Mongolia, Indonesia, Australia Coronavirus (MIACoV). (MIACoV)

A Randomised Controlled Trial to Assess the Immunogenicity, Safety, and Reactogenicity of Standard-dose Versus Fractional Doses of COVID-19 Vaccines (Pfizer-BioNTech or Moderna) Given as an Additional Dose After Priming With Pfizer-BioNTech or AstraZeneca in Healthy Adults in Australia-MIACoV

This is a single-blind, randomised controlled clinical trial to determine the reactogenicity and immunogenicity of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) vaccines (Pfizer-BioNTech or Moderna) as booster dose in adults, who have previously received either Pfizer-BioNTech or AstraZeneca as their primary doses.

Both fractional and standard doses of Pfizer-BioNTech or Moderna will be tested.

The trial intervention will be given in line with Australian Technical Advisory Group on Immunisation (ATAGI) recommendations for booster vaccine doses which allows booster doses from 5 months onwards . There will be a total of 8 groups, with 100 individuals of even spread of participants above and below 50 years in each group. The trial will be single site, based at Royal Children's Hospital, Melbourne, Australia

Study Overview

• Status: Terminated
• Conditions: COVID-19
• Intervention / Treatment: Biological: Tozinameran - Standard dose; Biological: Tozinameran - fractional dose; Biological: Elasomeran - standard dose; Biological: Elasomeran - fractional dose

Detailed Description

As per brief summary

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Phase 3

Contacts and Locations

Study Locations

• Australia
  • Victoria
    • Melbourne, Victoria, Australia, 3010
      • Royal Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Have completed two doses of Pfizer-BioNTech or AstraZeneca vaccines with the recommended schedule 6 months prior to the date of enrolment
2. Willing and able to give written informed consent
3. Aged 18 years or above
4. Willing to complete the follow-up requirements of the study

Exclusion Criteria:

1. Received 3 doses of COVID-19 vaccine
2. Received 2 doses of COVID-19 less than 6 months prior to the start of the trial
3. Received a different Covid-19 vaccine not available in Australia
4. Currently on immunosuppressive medication or anti-cancer chemotherapy
5. HIV infection
6. Congenital immune deficiency syndrome
7. Has received immunoglobulin or other blood products in the 3 months prior to vaccination
8. Study staff and their relatives
9. Have a history of a severe allergic reaction to any COVID-19 vaccines or have a medical exception to receiving further COVID-19 vaccines
10. Cannot read or understand English

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Standard Pfizer-BioNTech booster group; Received two doses of AstraZeneca or Pfizer-BioNTech as primary COVID-19 vaccine	Biological: Tozinameran - Standard dose; Tozinamrean is a single-stranded, 5'-capped messenger RNA (mRNA) produced using a cell-free in vitro transcription from the corresponding DNA templates, encoding the viral spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS_CoV-2). A standard dose will be administered on day 0 of the study.; Other Names: BNT162b2; Comirnaty; Pfizer-BioNTech
Experimental: Fractional Pfizer-BioNTech booster group; Received two doses of AstraZeneca or Pfizer-BioNTech as primary COVID-19 vaccine	Biological: Tozinameran - fractional dose; Tozinamrean is a single-stranded, 5'-capped messenger RNA (mRNA) produced using a cell-free in vitro transcription from the corresponding DNA templates, encoding the viral spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS_CoV-2). A fractional dose (15mcg) of the intervention will be administered on day 0 of the study.; Other Names: BNT162b2; Comirnaty; Pfizer-BioNTech
Active Comparator: Standard Elasomeran booster group; Received two doses of AstraZeneca or Pfizer-BioNTech as primary COVID-19 vaccine	Biological: Elasomeran - standard dose; Elasomeran is a single-stranded, 5'-capped messenger RNA (mRNA) produced using a cell-free in vitro transcription from the corresponding DNA templates, encoding the viral spike (S) protein of SARS-CoV-2). A single standard dose (50mcg) of the intervention will be administered on day 0 of the study.; Other Names: mRNA-1273; Moderna; Spikevax
Experimental: Fractional Elasomeran booster group; Received two doses of AstraZeneca or Pfizer-BioNTech as primary COVID-19 vaccine	Biological: Elasomeran - fractional dose; Elasomeran is a single-stranded, 5'-capped messenger RNA (mRNA) produced using a cell-free in vitro transcription from the corresponding DNA templates, encoding the viral spike (S) protein of SARS-CoV-2). A fractional dose (20mcg) of the intervention will be administered on day 0 of the study.; Other Names: mRNA-1273; Moderna; Spikevax

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
SARS-CoV-2 Specific Immunoglobulin (Ig)G Antibodies at 28-days Post Booster Vaccination	Serum samples collected at 28-days post booster vaccination from all 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	28-days post booster vaccination.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Interferon gamma (IFNγ) concentrations in International Units (IU)/mL	Interferon gamma (IFNγ) concentrations as a measurement of cellular immunity will be assessed on a subset (40%) of the participants from each group. QuantiFERON Human IFN-γ SARS-CoV-2 (Qiagen) will be used to stimulate IFN-γ production in peripheral blood mononuclear cells (PBMCs) and then IFN-γ production will be measured using ELISA. Data will be presented as geometric mean concentration (GMC) and 95% confidence intervals (CI).	Baseline (pre booster), 28 days-, and 6-months post booster vaccination
Number of IFNγ producing cells/million PBMCs	IFNγ producing cells as a measurement of cellular immunity will be assessed on a subset (40%) of the participants from each group. IFN-γ Enzyme-Linked ImmunoSpot (Elispot) assay will be performed on isolated peripheral blood mononuclear cells (PBMCs). Data will be reported as number of IFNγ producing cells/million and presented using means and 95% confidence intervals.	Baseline (pre booster), 28 days-, and 6-months post booster vaccination
Frequency of cytokine-expressing T cells	Frequency of cytokine-expressing T cells will be assessed on a subset (40%) of participants using Flow cytometry (intracellular staining) on PBMCs samples. Data will be reported as frequency (%) of cytokine-expressing T cells presented as means and 95% CI.	Baseline (pre booster), 28 days-, and 6-months post booster vaccination
Incidence of unsolicited adverse events (AE)	All unsolicited AE will be collected for 28 days post booster vaccination. Data will be presented as proportion of participants who report unsolicited AE.	28 days-post booster vaccination
Incidence of medically attended adverse events (AE)	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.	3 months post booster vaccination
Incidence of serious adverse events (SAE)	SAE will be collected throughout the follow-up period of 6 months post booster vaccination. Data will be presented as a proportion of participants who report unsolicited SAE.	6 months post booster vaccination
SARS-CoV-2 specific IgG antibodies at baseline (pre booster), and 6-months post booster vaccination.	Serum samples collected at baseline (pre booster), and 6-months post booster vaccination from all 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	Baseline (pre booster), and 6-months post booster vaccination
SARS-CoV-2 specific neutralising antibodies at baseline (pre booster), 28 days and 6-months post booster vaccination measured by surrogate virus neutralization test (sVNT)	Serum samples collected at baseline (pre booster), 28 days- and 6-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 Delta 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.	Baseline (pre booster), 28 days and 6 months post booster vaccination
SARS-CoV-2 specific neutralising antibodies at baseline (pre booster), 28 days and 6- months post booster vaccination measured by SARS-CoV-2 microneutralisation assay	A subset of samples from all four 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.	Baseline (pre booster), 28 days-, and 6-months post booster vaccination
Cytokine concentrations following PBMCs stimulation	Cytokine concentrations following PBMCs stimulation will be assessed on a subset (40%) of participants using multiplex cytokine assays.Data will be reported as cytokine concentrations in pg/ml and presented as GMC and 95% CI.	Baseline (pre booster), 28 days-, and 16-months post booster vaccination

Collaborators and Investigators

• Sponsor: Murdoch Childrens Research Institute
• Collaborators: Coalition for Epidemic Preparedness Innovations; The Peter Doherty Institute for Infection and Immunity
• Investigators: Principal Investigator: Kim Mulholland, MD, Murdoch Childrens Research Institute

Publications and helpful links

General Publications

• Munro APS, Janani L, Cornelius V, Aley PK, Babbage G, Baxter D, Bula M, Cathie K, Chatterjee K, Dodd K, Enever Y, Gokani K, Goodman AL, Green CA, Harndahl L, Haughney J, Hicks A, van der Klaauw AA, Kwok J, Lambe T, Libri V, Llewelyn MJ, McGregor AC, Minassian AM, Moore P, Mughal M, Mujadidi YF, Murira J, Osanlou O, Osanlou R, Owens DR, Pacurar M, Palfreeman A, Pan D, Rampling T, Regan K, Saich S, Salkeld J, Saralaya D, Sharma S, Sheridan R, Sturdy A, Thomson EC, Todd S, Twelves C, Read RC, Charlton S, Hallis B, Ramsay M, Andrews N, Nguyen-Van-Tam JS, Snape MD, Liu X, Faust SN; COV-BOOST study group. Safety and immunogenicity of seven COVID-19 vaccines as a third dose (booster) following two doses of ChAdOx1 nCov-19 or BNT162b2 in the UK (COV-BOOST): a blinded, multicentre, randomised, controlled, phase 2 trial. Lancet. 2021 Dec 18;398(10318):2258-2276. doi: 10.1016/S0140-6736(21)02717-3. Epub 2021 Dec 2. Erratum In: Lancet. 2021 Dec 18;398(10318):2246. doi: 10.1016/S0140-6736(21)02785-9.

Helpful Links

• US Food and Drug Administration (FDA). Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials 2007
• Quarter-dose of Moderna COVID vaccine still rouses a big immune response

Study record dates

Study Major Dates

• Study Start (Actual): May 2, 2022
• Primary Completion (Actual): July 25, 2022
• Study Completion (Actual): November 30, 2022

Study Registration Dates

• First Submitted: February 5, 2022
• First Submitted That Met QC Criteria: February 5, 2022
• First Posted (Actual): February 8, 2022

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 12, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Moderna; mRNA vaccine; COVID-19 vaccination; fractional and standard doses; Pfizer; Booster dose
• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19
• Other Study ID Numbers: 81764

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: We will share de-identified data to ethically approved studies in cases where participants have indicated on the consent form that they consent to the use of their data and where consistent with terms of collaboration agreements.
• IPD Sharing Time Frame: Individual participant data (IPD) sharing plans in development
• IPD Sharing Access Criteria: IPD sharing plans in development
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes