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SWITCH ON: Analysing the Immunogenicity of Additional Booster Vaccinations in HCW

SWITCH ON: Analysing the Immunogenicity of Additional Booster Vaccinations in Healthcare Workers. A Multicenter, Randomised, Controlled Trial

Status
UNKNOWN
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05471440
Acronym
SWITCHON
Enrollment
431
Registered
2022-07-22
Start date
2022-08-20
Completion date
2023-08-30
Last updated
2023-02-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Covid-19 Vaccination

Keywords

Covid-19, Boost

Brief summary

Eighty percent of the Dutch population has completed a primary COVID-19 vaccination regimen, and 60% of the population received a booster vaccination. Waning immunity, combined with the emergence of antigenically distinct SARS-CoV-2 variants, has led to the consideration of additional booster vaccinations in the Dutch population by autumn 2022. However, despite efforts of the Dutch policymakers, the public's willingness to repeatedly receive COVID-19 booster vaccinations is declining. This is mainly due to a reduced burden of disease by COVID-19, fewer hospitalizations, and fewer deaths. However, population immunity might be one of the major factors responsible for this reduced burden of disease, possibly emphasizing the need for booster vaccinations. In this proposal we will address an important question asked by policymakers: Are booster vaccinations in autumn recommended for the healthy population?

Interventions

DRUGDirect boost mRNA

Participants will be boosted with a covid-19 vaccin after priming with mRNA

DRUGDirect boost adeno

Participants will be boosted with a covid-19 vaccin after priming with adeno

DRUGPost-poned boost mRNA

Participants will be boosted with a covid-19 vaccin after priming with mRNA

DRUGPost-poned boost adeno

Participants will be boosted with a covid-19 vaccin after priming with adeno

Sponsors

ZonMw: The Netherlands Organisation for Health Research and Development
CollaboratorOTHER
Leiden University Medical Center
CollaboratorOTHER
University Medical Center Groningen
CollaboratorOTHER
Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)
CollaboratorOTHER
Erasmus Medical Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Intervention model description

A multicenter, randomized, controlled trial comparing immune responses 7 and 28 days after an additional COVID-19 booster vaccination between Janssen and mRNA primed HCWs to describe the immune response in a cohort representative of the Dutch population, in order to eventually provide data for Dutch policy makers

Eligibility

Sex/Gender
ALL
Age
18 Years to 67 Years
Healthy volunteers
Yes

Inclusion criteria

1. Participant is willing and able to give written informed consent for participation in the trial. 2. Adult (male/female) between 18 and 65 years old 3. Sufficient level of the Dutch language to undertake all study requirements

Exclusion criteria

1. Adults younger than 18 or older than 65 years. 2. Adults primed with another vaccine than Janssen, Moderna or Pfizer. 3. History of allergic reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Janssen/Pfizer/Moderna vaccine). 4. Adults that are pregnant. 5. Currently being treated for cancer. 6. Severe kidney failure or dialyses dependent. 7. Status after organ-, stem cell- or bone marrow transplantation. 8. Use of immunosuppressant's. 9. Epilepsy. 10. HIV. 11. Bleeding disorder (e.g. factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding of bruising following IM injections of vene puncture. 12. Continuous use of anticoagulants, such as coumarins (e.g. acenocoumarol) or novel oral anticoagulants (i.e. apixaban, dabigatran etc). 13. Participants who are currently participating in another research trial. 14. All regular contra-indications of the vaccines will be applied.

Design outcomes

Primary

MeasureTime frameDescription
Does booster vaccination lead to a rapid secondary recall response, indicative of immunological memory?28 daysOutcome: Level and fold change of antibodies and T-cell responses determined by a quantitative IgG assay and whole blood IFNγ release assay, respectively, comparing day 7 and 28 post-boost.
Is there an increase in antibody levels between day of boost and 28 days after boosting HCW that were initially primed with either the Janssen or an mRNA-based vaccine?28 daysOutcome: Level and fold change of antibodies determined by a quantitative IgG assay comparing the Janssen primed and mRNA-based primed HCW.

Secondary

MeasureTime frameDescription
What is the breadth of the immune responses after booster vaccination?28 daysOutcome: PRNT against relevant variants in a random selection of study participants.
What is the difference in reactogenicity 7 days after boost comparing the Janssen and mRNA primed HCW?7 daysOutcome: Adverse events (AE) first 7 days after an additional boost between Janssen and mRNA primed HCW.
Initial examination of breakthrough infections before and during study period1 yearOutcome: Database of breakthrough infections in included participants based on positive PCR, self-reported positive lateral flow test, or detection of N-specific antibodies.
What is the predictive value of immune responses on day 7 post boost?28 daysOutcome: Correlation between antibodies and T-cell responses on day 7 and 28 post boost in % of the 28 day response for both level of antibodies and T-cell responses
What is the difference in booster immunogenicity comparing a direct boost with a postponed boost?28 daysOutcome: Level of antibodies and T-cell responses 7 and 28 days post boost in DB versus PPB group.

Other

MeasureTime frameDescription
Gene expression profiles associated with recall response (PAXgene tube)28 days
SARS-CoV-2-specific T-cell responses28 daysPBMC, assessed by activation-induced marker assay and / or TCRbeta sequencing

Countries

Netherlands

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 11, 2026