Immune Response of an Interchangeable Booster Vaccine Against COVID-19 Among Individuals With Risk Factors for Severity

Study Overview
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Brief Summary
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Experimental, single-arm study in participants with comorbidities, previously immunized with 2 doses of CoronaVac, who will receive a booster vaccine with 1 dose of the Oxford/AstraZeneca vaccine.

Detailed Description
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Intervention: Oxford/AstraZeneca - 0.5 mL single dose, intramuscular in deltoid, with an interval of 180 days (+/- 30 days) from the 2nd dose of the initial vaccination schedule with CoronaVac Inclusion criteria: Have voluntarily participated and be in regular follow-up monitoring by the COVACMANAUS study; Have completed the vaccination schedule with 2 doses of CoronaVac, as per the COVACMANAUS study protocol for at least 180 days (+/- 30 days); Demonstrate availability to be followed during the follow-up period defined in the study, through visits, telephone contacts or other digital means of communication; Accept to participate in this new study for 6 (six) months. Exclusion criteria Confirmed diagnosis of COVID-19 within the last 28 days (antigen test or RT-PCR). In this situation, vaccination can be postponed until the participant completes 30 days; Report of fever within 72 hours prior to vaccination (inclusion can be postponed until the participant completes 72 hours without fever and COVID-19 is discarded); Having received live attenuated virus vaccine in the last 28 days or inactivated vaccine in the last 14 days prior to inclusion in the study; Any other condition that, in the opinion of the Principal Investigator or its medical representative, could jeopardize the safety or rights of a potential participant or prevent them from complying with this protocol; Pregnancy or lactation. Type of study/study design: Experimental, single-arm study in participants with comorbidities, previously immunized with 2 doses of CoronaVac, who will receive a booster vaccine with 1 dose of the Oxford/AstraZeneca vaccine. Sample size: all active participants from the COVACManaus study (up to 5071) Primary outcome: Detection and titration of antibodies against SARS-CoV-2 before (D0), at D90 and D180 after booster vaccination Secondary outcomes: Profile of the cell-mediated immune response in a subgroup of participants, before (D0), at D90 and D180 after booster vaccination; Ability to neutralize antibodies in a subgroup of participants before (D0), in D90 and D180 after the vaccine booster; Memory cell populations in a subgroup of participants before (D0), in D90 and D180 after booster vaccination. Detection and titration of antibodies against SARS-CoV-2 and its association with the history of physical activity or sedentary lifestyle.

Official Title
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The Effects of the Interchangeability of the Booster Vaccine Against COVID-19 on the Immune Response Among Education and Public Safety Workers With Risk Factors for Severity, in Manaus (Amazonas)

Conditions
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Comorbidities and Coexisting Conditions, Healthy

Intervention / Treatment
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* Other: Vaccine - ChAdOx1-S/nCoV-19 [recombinant]


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Have voluntarily participated and be in regular follow-up monitoring by the COVACMANAUS study; Have completed the vaccination schedule with 2 doses of CoronaVac, as per the COVACMANAUS study protocol for at least 180 days (+/- 30 days); Demonstrate availability to be followed during the follow-up period defined in the study, through visits, telephone contacts or other digital means of communication; Accept to participate in this new study for 6 (six) months. Exclusion criteria Confirmed diagnosis of COVID-19 within the last 28 days (antigen test or RT-PCR). In this situation, vaccination can be postponed until the participant completes 30 days; Report of fever within 72 hours prior to vaccination (inclusion can be postponed until the participant completes 72 hours without fever and COVID-19 is discarded); Having received live attenuated virus vaccine in the last 28 days or inactivated vaccine in the last 14 days prior to inclusion in the study; Any other condition that, in the opinion of the Principal Investigator or its medical representative, could jeopardize the safety or rights of a potential participant or prevent them from complying with this protocol; Pregnancy or lactation.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 49 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: Prevention
Intervention Model: Single Group Assignment
Interventional Model Description: Experimental, single-arm study in participants with comorbidities, previously immunized with 2 doses of CoronaVac, who will receive a booster vaccine with 1 dose of the Oxford/AstraZeneca vaccine (ChAdOx1-S/nCoV-19 [recombinant]).
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention - single arm<br>Oxford/AstraZeneca (ChAdOx1-S/nCoV-19 [recombinant]) - 0.5 mL single dose, intramuscular in deltoid, with an interval of 180 days (+/- 30 days) from the 2nd dose of the initial vaccination schedule with CoronaVac | Other: Vaccine - ChAdOx1-S/nCoV-19 [recombinant]<br>* ChAdOx1-S/nCoV-19 [recombinant] - 0.5 mL single dose, intramuscular in deltoid, with an interval of 180 days (+/- 30 days) from the 2nd dose of the initial vaccination schedule with CoronaVac<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Antibodies (detection and titration) against SARS-CoV-2 through quantitative test for total antibodies against viral nucleocapsid and IgG antibodies against Spike protein | Detection and titration of antibodies against SARS-CoV-2 at baseline (Day 0) and at Day 90 and Day 180 after booster vaccination | change from baseline (Day 0) antibodies against SARS-CoV-2 at Day 90 (D90) and Day 180 (D180) after booster vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Profile of the cell-mediated immune response in a subgroup of participants through cell immunophenotyping, using the Flow Cytometry (FC) technique. | • Profile of the cell-mediated immune response in a subgroup of participants, before (D0), at D90 and D180 after booster vaccination through cell immunophenotyping, using the Flow Cytometry (FC) technique. Memory T and B cell subpopulations will be labeled with monoclonal antibodies conjugated to pre-especified fluorochromes that bind to specific surface markers (clusters of differentiation) present in the populations of interest. | change from baseline profile (Day 0) of the cell-mediated immune response compared to Day 90 (D90) and Day 180 (D180) after booster vaccination | 
| Ability of the serum from a subgroup of participants to neutralize antibodies though viral neutralization assay at baseline (Day 0) and at Day 90 and D180 after vaccine booster dose | • Ability to neutralize antibodies in a subgroup of participants, through the Viral Neutralization Test (VNT) consisting of cultured Vero CCL-81 cells, inactivated serial diluted serum and fixation. | change from baseline (Day 0) profile of the ability to neutralize antibodies in a subgroup of participants at Day 90 (D90) and Day 180 (D180) after booster vaccination | 
| Quantification of memory cell populations in a subgroup of participants | • Profile of memory populations by cellular immunophenotyping in a subgroup of participants at baseline (Day 0) and in Day 90 and Day 180 after booster vaccination. | change from baseline (Day 0) memory cell populations in a subgroup of participants at Day 90 (D90) and Day 180 (D180) after booster vaccination | 
| Physical activity and its relationship with the acquisition of antibodies against SARS-CoV-2 after booster vaccination against SARS-CoV-2. | • Detection and titration of antibodies against SARS-CoV-2 and relationship with the history of physical activity during the follow-up period. To access physical activity the International Physical Activity Questionnaire (IPAQ) will be used and combined with the Duke Activity Status Index (DASI) questionnaire for sedentary lifestyle. | change from baseline (Day 0) antibodies against SARS-CoV-2 at Day 90 (D90) and Day 180 (D180) after booster vaccination and it relationship with the history of physical activity | 
| Sedentary lifestyle and its relationship with the acquisition of antibodies against SARS-CoV-2 after booster vaccination against SARS-CoV-2. | • Detection and titration of antibodies against SARS-CoV-2 and relationship with the history of sedentary lifestyle during the follow-up period. To access the sedentary lifestyle the Duke Activity Status Index (DASI) questionnaire will be used and combined with International Physical Activity Questionnaire (IPAQ) for physical activity. | change from baseline (Day 0) antibodies against SARS-CoV-2 at Day 90 (D90) and Day 180 (D180) after booster vaccination and it relationship with the history of sedentary lifestyle | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Covid19, vaccine, ChAdOx1-S/nCoV-19 [recombinant]