A Trial Among HealthCare Workers (HCW) Vaccinated With Janssen Vaccine: the SWITCH Trial

ABSTRACT

ConditionCovid19

InterventionBiological Vaccination once with Janssen vaccine (only priming);Biological Vaccination with Janssen vaccine followed with Janssen vaccine (homologous boosting).;Biological Vaccination with Janssen vaccine followed with Moderna vaccine (heterologous boosting).;Biological Vaccination with Janssen vaccine followed with Pfizer vaccine (heterologous boosting).

Primary outcome:Determination of antibodies by a quantitative IgG assay (LIAISON SARS-CoV-2 TrimericS IgG essay) 28 days after booster

Criteria
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 already vaccinated with other vaccine then Janssen

3. Previously had a COVID-19 infection

4. History of allergic reaction likely to be exacerbated by any component of study
vaccines (e.g. hypersensitivity to the active substance or any of the ingredients of
the Janssen/Pfizer/Moderna vaccine).

5. Adults that are pregnant or have a wish to become pregnant within 6 months

6. Currently being treated for cancer

7. Severe kidney failure or dialyses dependent

8. Status after organ-, stem cell- or bone marrow transplantation

9. Use of immunosuppressant's

10. Epilepsy

11. HIV

12. Bleeding disorder (e.g. factor deficiency, coagulopathy or platelet disorder), or
prior history of significant bleeding of bruising following injections of vene
puncture

13. Continuous use of anticoagulants, such as coumarins (e.g. acenocoumarol) or novel oral
anticoagulants (i.e. apixaban, dabigatran etc).

14. Participants who are currently participating in another research trial.

15. All regular contra-indications of the vaccines will be applied.