The response after the first and second dose of the BNT162b2 Covid-19 vaccine: real-world evidence from Greece
| ISRCTN | ISRCTN61884303 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN61884303 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | Nil known |
| Sponsor | Georgios Gennimatas General Hospital |
| Funder | investigator initiated and funded |
- Submission date
- 08/02/2021
- Registration date
- 10/02/2021
- Last edited
- 06/03/2024
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Other
Plain English summary of protocol
Background and study aims
mRNA vaccines are a new type of vaccine to protect against infectious diseases. To trigger an immune response, many vaccines put a weakened or inactivated germ into our bodies. Not mRNA vaccines. Instead, they teach our cells how to make a protein—or even just a piece of a protein—that triggers an immune response inside our bodies. That immune response, which produces antibodies, is what protects us from getting infected if the real virus enters our bodies.
The aim of this study is to enhance insight into the immunity and antibody generation elicited by the first and second dose of the BNT162b2 mRNA Covid-19 vaccine.
Who can participate?
Adult healthcare workers aged 18 - 69 years. Our study population includes both uninfected vaccinated persons and persons with PCR-confirmed previous SARS-CoV-2 infection occurring one to 4.5 months prior to vaccination.
What does the study involve?
Healthcare workers vaccinated in the two vaccination centers of the “G. Gennimatas” General Hospital of Thessaloniki will be followed for one year post-injection of the second dose of the vaccine.
What are the possible benefits and risks of participating?
None
Where is the study run from?
“G. Gennimatas” General Hospital of Thessaloniki (Greece)
When is the study starting and how long is it expected to run for?
December 2020 to March 2022
Who is funding the study?
Investigator initiated and funded
Who is the main contact?
Georgios Papazisis, papazisg@auth.gr
Contact information
Public
University Campus
Thessaloniki
54624
Greece
 ORCID ID |
0000-0003-1641-9095 |
|---|---|
| Phone | +30 2310999323 |
| papazisg@auth.gr |
Study information
| Primary study design | Observational |
|---|---|
| Study design | Observational prospective single-center study |
| Secondary study design | Longitudinal study |
| Study type | Participant information sheet |
| Scientific title | Immunogenicity after the first and second dose of the BNT162b2 mRNA Covid-19 vaccine: real-world evidence from Greece |
| Study acronym | GREVACIM |
| Study objectives | Several prophylactic vaccines against SARS-CoV-2 were recently launched after solid proof of their efficacy and safety was provided by clinical trials. However, real world data on the immunogenicity of these vaccines remain scarce. Our study aims at enhancing current insight into the humoral immunity and neutralizing antibody generation elicited by the first and second dose of the BNT162b2 mRNA Covid-19 vaccine. For that matter, we measured the concentration of specific anti-SARS-CoV-2 IgGs acting against the receptor-binding domain (RBD) of the S1 subunit of the viral spike protein, performing a chemiluminescent microparticle immunoassay. |
| Ethics approval(s) | Approved 13/01/2021, Ethics committee of the scientific council of the G. Gennimatas General Hospital (Ethnikis Aminis 41, postal code 54631, Thessaloniki, Greece; +30 2310963179; Konstantinakontopoulou9@gmail.com), ref: 1/13.1.2021 |
| Health condition(s) or problem(s) studied | BNT162b2 mRNA COVID-19 vaccine immunogenicity among healthcare workers |
| Intervention | Based on the national prioritization scheme, healthcare providers were the first population group to receive the BNT162b2 mRNA Covid-19 vaccine in Greece. The first cohort of healthcare workers vaccinated in the two vaccination centers of the “G. Gennimatas” General Hospital of Thessaloniki will be followed for one year post-injection of the second dose of the vaccine. The titers of anti-SARS-CoV-2 antigen-specific IgGs will be monitored 14 days after the first dose and 14 days, 3, 6, 9 and 12 months after the second dose. The SARS-CoV-2 IgG II Quant assay on the ARCHITECT System will be conducted on participant-derived serum samples. Reactogenicity data regarding the BNT162b2 mRNA Covid-19 vaccine will also be collected. |
| Intervention type | Biological/Vaccine |
| Phase | Phase IV |
| Drug / device / biological / vaccine name(s) | BNT162b2 mRNA COVID-19 vaccine |
| Primary outcome measure(s) |
Immunogenicity of the BNT162b2 mRNA Covid-19 vaccine measured using the SARS-CoV-2 IgG II Quant assay to conduct a qualitative and quantitative determination of IgGs against the receptor-binding domain (RBD) of the S1 subunit of the SARS-CoV-2 spike protein on day 14 after the first dose, day 14 after the second dose and within 3, 6, 9 and 12 months after the second dose. |
| Key secondary outcome measure(s) |
1. PCR-confirmed cases of SARS-CoV-2 infection anytime after the first dose measured using hospital records |
| Completion date | 30/03/2022 |
Eligibility
| Participant type(s) | Health professional |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 69 Years |
| Sex | All |
| Target sample size at registration | 450 |
| Total final enrolment | 425 |
| Key inclusion criteria | 1. Age of 18 - 69 years 2. Without previously known SARS-CoV-2 infection, or 3. With previous PCR-confirmed SARS-CoV-2 infection one to 4.5 months prior to vaccination |
| Key exclusion criteria | 1. Occurence of any other vaccination 4 weeks prior to enrollment 2. Pregnancy or breastfeeding 3. Participation in any other clinical trial |
| Date of first enrolment | 25/01/2021 |
| Date of final enrolment | 28/02/2022 |
Locations
Countries of recruitment
- Greece
Study participating centre
Thessaloniki
54635
Greece
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request |
| IPD sharing plan | The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request. Completely anonymised, de-identified (stripped of all “direct identifiers”) numerical data in spreadsheets will be shared with researchers from the academia and relevant research institutions after the publication of corresponding results in peer-reviewed academic journals, for purposes of independent statistical analysis and verification of results. Participants provided consent for the use of anonymised data for research purposes. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | 01/08/2021 | 06/03/2024 | Yes | No | |
| Results article | 30/05/2022 | 06/03/2024 | Yes | No | |
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
06/03/2024: Publication references and total final enrolment added.
10/02/2021: Trial’s existence confirmed by G. Gennimatas General Hospital.
