Impact of BCG vaccination, originally made to prevent tuberculosis, on the immune response to the COVID-19 vaccine in health care workers

Effect of Bacillus Calmette-Guérin vaccination on the immunogenicity of the mRNA BNT162b2 COVID-19 vaccine in health care workers - COMBI study

Status

Not yet recruiting

Phases

Phase 4

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2021-000182-33-NL

Enrollment

Registered

2021-01-21

Start date

2021-03-25

Completion date

Unknown

Last updated

2021-03-30

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

Conditions

Immunogenicity of the mRNA BNT162b2 COVID-19 vaccine.

Interventions

Trade Name: Comirnaty Product Name: Comirnaty Pharmaceutical Form: Concentrate and solvent for solution for injection

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: - Age equal to or above 18 years; - Written informed consent provided by the participant; - Receiving BioNTech/Pfizer COVID-19 vaccine per routine care; - Having received BCG-vaccination in the past 12 months OR never having received BCG-vaccination. Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 40 F.1.3 Elderly (>=65 years) no F.1.3.1 Number of subjects for this age range

Exclusion criteria

Exclusion criteria: - Legally incapacitated or unwilling to provide informed consent; - History of COVID-19 infection, confirmed by a microbiological test.

Design outcomes

Primary

Measure	Time frame
Main Objective: The main objective is to analyze whether BCG-vaccination prior to COVID-19 vaccination can enhance the immunogenicity of the COVID-19 mRNA vaccine developed by BioNTech and Pfizer.;Secondary Objective: Secondary objectives are to determine if antibody concentrations against SARS-CoV-2 antigens in nasal mucosal lining fluid at the various sampling time points can be detected and if prior BCG vaccination leads to more severe local or systemic reactions after COVID-19 vaccination. ;Primary end point(s): Seroconversion of IgG to the SARS-CoV-2 spike protein at day 21 after the first dose of Pfizer/BioNTech BNT162B2. Seroconversion of antibodies is defined as a change from seronegative at baseline (pre-1st dose of Pfizer/BioNTech BNT162B2) to seropositive or a =four-fold titer increase if the participant is seropositive at baseline;Timepoint(s) of evaluation of this end point: The primary endpoint will be analyzed when all blood samples of timepoint Day 21 have been collected.	—

Measure

Time frame

Main Objective: The main objective is to analyze whether BCG-vaccination prior to COVID-19 vaccination can enhance the immunogenicity of the COVID-19 mRNA vaccine developed by BioNTech and Pfizer.;Secondary Objective: Secondary objectives are to determine if antibody concentrations against SARS-CoV-2 antigens in nasal mucosal lining fluid at the various sampling time points can be detected and if prior BCG vaccination leads to more severe local or systemic reactions after COVID-19 vaccination. ;Primary end point(s): Seroconversion of IgG to the SARS-CoV-2 spike protein at day 21 after the first dose of Pfizer/BioNTech BNT162B2. Seroconversion of antibodies is defined as a change from seronegative at baseline (pre-1st dose of Pfizer/BioNTech BNT162B2) to seropositive or a =four-fold titer increase if the participant is seropositive at baseline;Timepoint(s) of evaluation of this end point: The primary endpoint will be analyzed when all blood samples of timepoint Day 21 have been collected.

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Secondary

Measure	Time frame
Secondary end point(s): - Geometric mean concentrations (GMCs) of RBD- and S-specific IgG, IgA and IgM in serum at day 21, 35, month 6 and 12; - IgG, IgA and IgM concentrations against SARS-CoV-2 antigens in nasal mucosal lining fluid at the various sampling time points; - Local reactions at injection site or systemic reactions after COVID-19 vaccination; - T-cell responses and monocyte cytokine response to ex vivo stimulation at the various time points. ;Timepoint(s) of evaluation of this end point: Secondary analyses will need data from follow-up of the study and will be performed at the end of the study.	—

Measure

Time frame

Secondary end point(s): - Geometric mean concentrations (GMCs) of RBD- and S-specific IgG, IgA and IgM in serum at day 21, 35, month 6 and 12; - IgG, IgA and IgM concentrations against SARS-CoV-2 antigens in nasal mucosal lining fluid at the various sampling time points; - Local reactions at injection site or systemic reactions after COVID-19 vaccination; - T-cell responses and monocyte cytokine response to ex vivo stimulation at the various time points. ;Timepoint(s) of evaluation of this end point: Secondary analyses will need data from follow-up of the study and will be performed at the end of the study.

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Countries

Netherlands

Contacts

Public ContactKonstantin Föhse

Radboudumc

konstantin.fohse@radboudumc.nl

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026