Sars-COV-2 (COVID-19) Immunity in immunoCOmpromised Populations

Study Overview
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Brief Summary
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The immune response of COVID-19 vaccination was monitored and studied in the context of the previously PICOV study (P2020/424), Nephro- VAC studies (P2020/284 and P2020/312) and Lung-VAC study (P2021/182). The constant emergence of new variants of concern (VOCs), which become increasingly better at escaping infection and vaccine induced immune responses, together with waning immunity over time, warrant additional vaccination rounds. This is especially true in immunocompromised populations. In the current study, we want to continue monitoring SARS-CoV-2 specific immunity over the next two years, encompassing several future vaccination campaigns.

Detailed Description
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Background: In collaboration with several Belgian universities, hospitals and institutes, Sciensano, the Belgian Scientific Institute of Public Health, set up a consortium to facilitate and streamline the organization of COVID-19 vaccination studies primarily in immunocompromised populations. The immune response of COVID-19 vaccination was monitored and studied in the context of the previously PICOV study (P2020/424), Nephro- VAC studies (P2020/284 and P2020/312) and Lung-VAC study (P2021/182). The constant emergence of new variants of concern (VOCs), which become increasingly better at escaping infection and vaccine induced immune responses, together with waning immunity over time, warrant additional vaccination rounds. This is especially true in immunocompromised populations. In the current study, we want to continue monitoring SARS-CoV-2 specific immunity over the next two years, encompassing several future vaccination campaigns. Method: A non-commercial multicenter academic prospective cohort study will be conducted in immunocompromised populations and healthy adults for two years. These healthy people will be recruited from the previously organized PICOV-VAC study (members of nursing home staff) (EudraCT 2021-000401-24) and REDU-VAC study (EudraCT 2021-002088-23) while the immunocompromised participants will be recruited from the previously established PICOV-VAC, REDU-VAC, Lung-VAC and Nephro-VAC cohorts from which historic clinic and immunologic data is available. Participants will be sampled three times a year independently of the vaccinations which will be administered through regular channels not linked to the study itself. Objectives: The main goal of this study is to measure levels of immunity in healthy adults and immunocompromised participants three times a year. The primary objective is to determine binding and neutralizing antibody levels against the epidemiologically predominant SARS- CoV-2 variants of concern (VOC) and the wild type SARS-CoV-2 (Wuhan strain). This will allow us to determine to which extent extra booster doses can or cannot induce more (binding) and/or better (neutralizing) antibodies to different variants as compared to peak responses achieved after previous vaccination doses and to study waning of these responses after winter periods. Secondary objectives include studying the vaccine induced immunity in more detail. This includes the further characterization of the quality of the antibody response and the measurement of the cellular immune response, amongst others.

Official Title
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Longitudinal Follow-up of SARS-CoV-2 (COVID-19) Immunity in Immunocompromised Populations in Belgium (COVICO) in Nursing Home Residents and Staff During the Winter Season 2022-2023

Conditions
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SARS CoV 2 Infection, COVID-19

Intervention / Treatment
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* Diagnostic Test: Humoral immunity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Being a resident or member of staff in a nursing home and having participated in the previously organized PICOV-VAC study. Being cognitively capable to give consent to participate in the study. Being a healthy adults and having participated in the previous REDU-VAC study Being a kidney transplant or dialysis patient and having participated in the previous NEPHRO-VAC study Being a lung transplant patient and having participated in the previous LUNG-VAC study Exclusion Criteria: Having insufficient knowledge of the Dutch or French language.. Having a previous diagnosis of dementia and/or having a mini-mental state examination (MMSE) score < 18/30. Having veins which are not accessible for simple peripheral blood puncture.

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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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: the intervention is the blood sampling
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Residents and staff from nursing homes from the previous PICOV-VAC study<br> | Diagnostic Test: Humoral immunity<br>* determine binding and neutralizing antibody levels against the epidemiologically predominant SARS- CoV-2 variants of concern (VOC) and the wild type SARS-CoV-2 (Wuhan strain).<br>|
| Experimental: Healthy adults from the previous REDU-VAC study<br> | Diagnostic Test: Humoral immunity<br>* determine binding and neutralizing antibody levels against the epidemiologically predominant SARS- CoV-2 variants of concern (VOC) and the wild type SARS-CoV-2 (Wuhan strain).<br>|
| Experimental: Kidney transplant and dialysis patients from the previous NEPHRO-VAC study<br> | Diagnostic Test: Humoral immunity<br>* determine binding and neutralizing antibody levels against the epidemiologically predominant SARS- CoV-2 variants of concern (VOC) and the wild type SARS-CoV-2 (Wuhan strain).<br>|
| Experimental: Lung transplant patients from the previous LUNG-VAC study<br> | Diagnostic Test: Humoral immunity<br>* determine binding and neutralizing antibody levels against the epidemiologically predominant SARS- CoV-2 variants of concern (VOC) and the wild type SARS-CoV-2 (Wuhan strain).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentration of SARS-CoV-2 binding and neutralizing antibodies | change in the concentration of binding and neutralizing antibodies against the epidemiologically predominant SARS-CoV-2 variant of concern (VOC) and the wild type SARS-CoV-2 (Wuhan strain) | Three times a year, during two years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maturation of specific antibody affinity to SARS-CoV-2 | change in SARS-CoV-2 specific antibody affinity maturation | Three times a year, during two years | 
| Levels of mucosal antibodies to SARS-CoV-2 | change of the mucosal antibodies to SARS-CoV-2 | Three times a year, during two years | 
| Frequencies of T and B cell to SARS-CoV-2 | change of SARS-CoV-2 specific cellular immunity | Three times a year, during two years | 
| Levels of non-neutralizing functions of antibodies to SARS-CoV-2 | change of levels the non-neutralizing functions of antibodies | Three times a year, during two years |