Immune Response to Vaccination Against Covid-19, a Follow up Study

Study Overview
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Brief Summary
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The study investigates the immune response after vaccination in individuals with and without pre-existing immunity to Coronavirus disease (COVID) -19. The participants are followed and sampled up to 4 years after vaccination. Blood samples are collected at different timepoints to analyze immune response. The aim is to investigate the level of specific antibodies to Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) yearly, up to 4 years after vaccination.

Detailed Description
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The main objective is to investigate if the antibody development to SARS-CoV-2 S protein differ after vaccination in those who have had a previous SARS-CoV-2 infection compared to Covid-19 naive individuals. The secondary objective is to improve the understanding of the cellular and serological immune response after vaccination against COVID-19 in these groups. Individuals with and without pre-existing immunity to COVID-19 are included in the study. They are included after informed consent at sites where they receive vaccines against COVID-19 within the national and regional vaccine campaign. The study includes all approved COVID-19 vaccines with marketing authorization in Sweden. Persons are enrolled after the first or second dose of vaccination and followed 4 years after vaccination. Blood is collected at inclusion and 3 months, 6 months, 1 year, 2 years, 3 years and 4 years after vaccination to assess the immune response. Data on sex, age, body mass index, medical history and concomitant medication is collected. The study is a follow-up study after vaccination and approved by the Swedish Medical Products Agency (EudraCT 2021-000683-30). Regular monitoring of the study is performed by the Clinical Trial unit at Umeå University Hospital.

Official Title
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CoVacc - Immune Response to Vaccination Against Covid-19, an Open Multicenter Phase IV Study

Conditions
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Vaccination; Infection, Covid19

Intervention / Treatment
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* Drug: Vaccination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Consents to participate in the study Age ≥ 18 years Exclusion Criteria: Age <18 years Incapable of giving informed consent Contraindication to vaccination Severe disease Ongoing treatment that is judged to affect the vaccine response (Does not include Rituximab which is allowed after individual consideration). Steroids > 15 mg orally per day.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Post-COVID-19<br>Persons with a verified previous COVID-19 infection | Drug: Vaccination<br>* Persons that are vaccinated within the national and regional vaccine program are invited to participate in the follow-up study.<br>|
| COVID-19 naive<br>Persons that have no history of COVID-19 | Drug: Vaccination<br>* Persons that are vaccinated within the national and regional vaccine program are invited to participate in the follow-up study.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in levels of specific IgG antibody against SARS-CoV-2 after vaccination over time. | Levels of specific IgG antibody against SARS-CoV-2 will be measured as optical density, OD in a specific Spike-protein IgG ELISA at each time-point. | 1 and 6 months, 1, 2, 3, and 4 years after vaccination. | 
| Change in proportion of participants with detectable specific IgG antibodies after vaccination over time. | Immune response will be measured as the proportion of participants (in % of all vaccinated individuals) with detectable specific IgG antibodies after vaccination at each time-point (in months after vaccination). | 1 and 6 months, 1, 2, 3, and 4 years after vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Levels of markers for immune response after infection and vaccination against COVID-19 in COVID-naive versus COVID experienced individuals. | Levels of markers for cellular and serological immune response after COVID-19 vaccination e.g. specific antibodies, T- and B-cell memory. | Change of markers for cellular and serological immune response over time measured at 1 and 6 months, 1, 2, 3, and 4 years after vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Immune response, Immunoglobulin G