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Covid19Phase 4COVACMANAUSNCT04789356

Effectiveness of the Adsorbed Vaccine COVID-19 (Coronavac) Among Education and Public Safety Workers With Risk Factors for Severity

A Phase 4 study testing Adsorbed SARS-CoV-2 (inactivated) vaccine in people with Covid19, run by Fundação de Medicina Tropical Dr. Heitor Vieira Dourado at 1 site in Brazil.

Unknown status

Status not confirmed. The sponsor has not verified this record for over two years, so it may be out of date.

Official record
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Trial summary

This is a quasi-experimental study with risk-based allocation. Public security and education professionals from the state government will be included. In the initial evaluation, the presence of comorbidities associated with an increased risk of serious disease due to COVID-19 will be evaluated, according to the… Read more about this study

Who is it for?
Ages 18 to 49 yearsHealthy volunteers can take part
Conditions the study is for
Covid19
What is being tested?
Adsorbed SARS-CoV-2 (inactivated) vaccine
Could I receive a placebo?
No, everyone receives an active treatment
How many people
6,233 participants
Where
1 siteBrazil
Study dates
18 Mar 2021to Mar 2022
Phase
Phase 4
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 49 years
  • All sexes
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Age between 18 and 49 years
  • Demonstrate availability to be accompanied during the follow-up time defined in the study, through visits, telephone contacts, or other means of digital communication.

Who cannot join

  • Prior vaccination for COVID-19;
  • Diagnosis of COVID-19 in the last 28 days (nasal and oropharyngeal swab);
  • History of severe allergic reaction or anaphylaxis to study vaccine components;
  • Report of fever in the 72 hours prior to vaccination (the inclusion may be postponed until the participant completes 72 hours without fever);
  • Possible or confirmed of COVID-19 on the day of vaccination (in this situation, vaccination can be postponed until the participant completes 72 hours without symptoms or the diagnosis is ruled out);
  • Have received live attenuated virus vaccine in the last 28 days or inactivated vaccine in the last 14 days prior to inclusion in the study, or have immunization scheduled for the first 28 days after their inclusion in the study;
  • Any other condition that, in the opinion of the principal investigator or his medical representative, could endanger the safety or rights of a potential participant or that would prevent him or her from complying with this protocol;
  • Pregnancy or breastfeeding.

Trial locations and contacts

1 site in 1 country.

Brazil1 site

  • Escola Normal Superior - Universidade do Estado do Amazonas

    Manaus, Amazonas, 69050-010

Other trials in Brazil

About this study

Official title: Phase IV Study to Evaluate the Effectiveness of the Inactivated Adsorbed Vaccine Against COVID-19 CoronaVac, Among Public Safety and Education Workers With Risk Factors for Severity, in Manaus (Amazonas)

This is a quasi-experimental study with risk-based allocation. Public security and education professionals from the state government will be included. In the initial evaluation, the presence of comorbidities associated with an increased risk of serious disease due to COVID-19 will be evaluated, according to the national plan for the implementation of vaccination against COVID-19. Those with at least one of these comorbidities will be invited to receive the study vaccine in two doses, with an interval of 28 days (±7 days). Participants with low risk (without comorbidities as a risk factor for severe COVID-19 according to the national plan for the implementation of vaccination against COVID-19) will not receive the vaccine within the scope of the research project. If, after 12 months, the participant in the low-risk group (no vaccine) has not received CoronaVac, or any other vaccine available, he/she will receive the vaccine, exactly as offered in the other group (two doses of CoronaVac with an interval of 28 days - with a tolerance of 7 days before or after). All participants will be followed up for 12 months from inclusion in the study. Immunization is expected to reduce the risk of moderate to severe disease of those with comorbidities to the level of those of the same age group who do not have these comorbidities but face similar occupational risks.

Conditions
Covid19
Being tested
Adsorbed SARS-CoV-2 (inactivated) vaccine
Keywords
SARS-CoV-2, Brazil, Covid-19, Vaccine, Sinovac, CoronaVac, Vaccine efficacy
Medical subject headings
COVID-19

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Adsorbed SARS-CoV-2 (inactivated) vaccineBiological

    Also called CoronaVac

    600 SU/dose; Two doses separated by 28 days (± 7 days). Intramuscular (deltoid) administration.

Study groups in NCT04789356
Study groupRoleWhat they receive
High-risk individuals (with comorbidities)Active comparatorPublic safety and security (police officers and law enforcement, fire department), and high school and college/university professionals of the state government public education network who present at least one of the comorbidities included in the National Plan for the Operationalization of Vaccination Against COVID-19 will be invited to receive the CoronaVac vaccine
Receives: Biological: Adsorbed SARS-CoV-2 (inactivated) vaccine
Low-risk individuals (without comorbidities)No interventionParticipants with low risk (without comorbidities as a risk factor for severe COVID-19 according to the national plan for the implementation of vaccination against COVID-19) will not receive the vaccine within the scope of the research project.

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Incidence density of moderate and severe clinical cases of COVID-19

    Incidence density of moderate and severe clinical cases of COVID-19 (Grade 4 or higher according to the WHO clinical progression scale), after the second week after the second dose of the vaccine.

    Measured: 2 weeks after the second vaccine dose

Secondary outcomes (11)

  1. Incidence density of moderate and severe clinical cases of COVID-19 after first dose

    Incidence density of moderate and severe clinical cases of COVID-19 (grade 4 or higher according to the WHO clinical progression scale) from the first dose

    Measured: After first dose, up to 12 months.

  2. Incidence density of moderate and severe clinical cases of COVID-19 after second dose

    Incidence density of moderate and severe clinical cases of COVID-19 (grade 4 or higher according to the WHO clinical progression scale) from the second dose

    Measured: After second dose, up to 12 months.

  3. Incidence density of severe clinical cases of COVID-19 after second dose

    Incidence density of severe clinical cases of COVID-19 (grade 6 or higher according to the WHO clinical progression scale) from the second dose

    Measured: After second dose, up to 12 months.

  4. Median of clinical progression scores between moderate and severe cases

    Comparison of the median clinical progression scores according to the WHO clinical progression scale between groups

    Measured: After first dose, up to 12 months.

  5. Incidence density of clinical cases virologically confirmed as COVID-19

    Measured: After first dose, up to 12 months.

  6. Mortality confirmed as COVID-19

    Incidence density of deaths confirmed as COVID-19

    Measured: After first dose, up to 12 months.

  7. Incidence density of hospitalizations for any cause

    Measured: After first dose, up to 12 months.

  8. Mortality from any cause

    Density of mortality from any cause

    Measured: After first dose, up to 12 months.

  9. Adverse events

    Frequency of adverse events associated with the need for medical care

    Measured: Up to 7 days after each dose of the vaccine (Day 7 and Day 35)

  10. Humoral and cell-mediated immune response

    Quantification of humoral and cell-mediated immune response to vaccination in samples of a subgroup of participants

    Measured: Before each vaccine dose and every 3 months, up to 12 months of follow-up.

  11. Detection of antibodies against SARS-CoV-2 in samples

    Measured: Before each vaccine dose and every 3 months, up to 12 months of follow-up

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted9 Mar 2021
  2. Study start18 Mar 2021
  3. Primary completion5 Jul 2021
  4. Study completionMar 2022 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 4
Primary purpose
Treatment
Allocation
Non-randomised
Intervention model
Parallel groups
Model description
Quasi-experimental study
Masking
None (open label)
Enrolment
6,233 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04789356
Sponsor's protocol ID
CAAE: 44076721.5.0000.0005
Acronym
COVACMANAUS
Status last verified
Jul 2021
First submitted
5 Mar 2021
Last updated
26 Jul 2021
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Undecided

Publications

  • Martins A, Bosco Santos MF, Nascimento J, da Silva Chui FM, Almeida Rodrigues MG, Bastos T, Lemos S, Honorato E, Cortez M, Xavier MS, Gomes EO, Abreu-Netto RL, Fernandes S, Silva-Neto AV, Sachett A, Silva BM, Mouta GS, Cordeiro JSM, Baia-da-Silva DC, Brito-Sousa JD, Pessoa KP, Nogueira ML, Palacios R, Monteiro W, Naveca F, Sampaio V, Almeida-Val F, Melo G, Ranzani O, Mourao MP, Lacerda M. Effectiveness of CoronaVac in a pioneer risk-based allocation clinical trial during the COVID-19 pandemic. PLoS One. 2026 Jun 22;21(6):e0351566. doi: 10.1371/journal.pone.0351566. eCollection 2026.

    PubMed 42329996

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing Adsorbed SARS-CoV-2 (inactivated) vaccine in people with Covid19, run by Fundação de Medicina Tropical Dr. Heitor Vieira Dourado at 1 site in Brazil.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: status not confirmed, as of the sponsor's last update on 26 Jul 2021. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Brazil. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Results are not available in the source record.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Incidence density of moderate and severe clinical cases of COVID-19 (time frame: 2 weeks after the second vaccine dose). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04789356, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Jul 2021.

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