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SARS-CoV-2Phase 2/3NCT05059106

EFFECTIVENESS, SAFETY AND IMMUNOGENICITY OF THE HALF DOSE OF THE VACCINE ChadOx1 nCoV-19 (AZD1222) for COVID-19

A Phase 2/3 study testing Half dose of ChAdOx1 nCoV-19 (AZD1222) and Standard dose of ChAdOx1 nCoV-19 (AZD1222) in people with SARS-CoV-2, run by Federal University of Espirito Santo 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 The sponsor has not verified this record for over two years, so it may be out of date.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 study is clinical trial (intervention study with external comparison group) to test vaccination with reduced dose (half dose) of ChAdOx1 nCoV-19 (AZD1222), in a 2-dose schedule with an interval of 8 weeks, including all adults aged 18 to 49 years from Viana city - Espírito Santo (ES)/Brazil, on the incidence of… Read more about this study

Who is it for?
Ages 18 to 49 yearsHealthy volunteers can take part
Conditions the study is for
SARS-CoV-2
What is being tested?
Half dose of ChAdOx1 nCoV-19 (AZD1222) and Standard dose of ChAdOx1 nCoV-19 (AZD1222)
Type of treatment
Vaccines
Could I receive a placebo?
No, everyone receives an active treatment
How many people
29,637 participants
Where
1 siteBrazil
Study dates
1 Jun 2021to 30 Oct 2022
Phase
Phase 2/3
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

  • residents of Viana, Espírito Santo, aged between 18 and 49 years

Who cannot join

  • Pregnant women;
  • History of severe allergic reaction (anaphylaxis) to any previously administered vaccine;
  • Having received another vaccine in the last 14 days;
  • Belonging to a priority risk group for vaccination, as per the PNI recommendations;
  • Have fever or flu-like symptoms;
  • Have previously received any vaccine for covid-19 at any time;
  • Recent diagnosis of covid-19 with onset of symptoms 28 days before vaccination;
  • Disorders of coagulation and use of anticoagulants.

Trial locations and contacts

1 site in 1 country.

Valéria Valim, PhD contact

+5527999874665

val.valim@gmail.com

Brazil1 site, 1 recruiting

  • Federal University of Espirito Santo

    Vitória, Espírito Santo, 29041-295

    Valéria Valim, PhD, +55 27 99987-4665, val.valim@gmail.com

    José G Mill, PhD

    Recruiting

Other trials in Brazil

About this study

This study is clinical trial (intervention study with external comparison group) to test vaccination with reduced dose (half dose) of ChAdOx1 nCoV-19 (AZD1222), in a 2-dose schedule with an interval of 8 weeks, including all adults aged 18 to 49 years from Viana city - Espírito Santo (ES)/Brazil, on the incidence of new cases over 12 months following treatment, compared to an external group from same state and adjusted for socio-demographic and epidemiological variables.

Read the detailed description

This study is clinical trial (intervention study with external comparison group) to test vaccination with reduced dose (half dose) of ChAdOx1 nCoV-19 (AZD1222), in a 2-dose schedule with an interval of 8 weeks, including all adults aged 18 to 49 years from Viana city - Espírito Santo (ES)/Brazil, on the incidence of new cases over 12 months following treatment, compared to an external group from same state and adjusted for socio-demographic and epidemiological variables. Cellular and humoral immunity will be studied in a representative sub-sample compared to an external reference group (cohort of health workers) vaccinated with standard dose. The outcomes will be evaluated at 28 days after the second dose and follow-up after 6 months and 12 months. The main outcome will be to decrease in 60% the incidence of new cases over 6 months after receiving the vaccine. The clinical epidemiological variables will be obtained from e-SUS VS, e-SUS notifica and datasus: number of cases, number of deaths with specific ICD for covid-19, number of hospital admissions for covid-19; number of ICU admissions for the treatment of SARS, total number of tests (RT-PCR) performed and positive. The cellular and humoral immune response will be assessed by viral neutralization assay (neutralizing antibody test), serological assay by chemiluminescence, determination of specific IgM and IgG profiles, measurement of systemic soluble factors (chemokines, cytokines and growth factors), stimulation antigen-specific peripheral blood mononuclear cells in vitro and investigation of memory T and B lymphocytes and intracytoplasmic cytokines. It is estimated to include 29,637 people in the study, to reach 85% vaccination cover of individuals aged 18-49 years. The subsample size immunogenicity test is 600 individuals from the eligible population, estimating losses of 15% and study power of 90%, alpha error of 1%. The hypothesis of the study is that the reduction in the incidence of covid-19 and the cellular and humoral immune response achieved with a half dose will be similar to the reduction expected with the standard dose.

Conditions
SARS-CoV-2
Being tested
Half dose of ChAdOx1 nCoV-19 (AZD1222), Standard dose of ChAdOx1 nCoV-19 (AZD1222)
Keywords
vaccines, immunity, covid-19
Medical subject headings
COVID-19

What participants receive

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

  • Half dose of ChAdOx1 nCoV-19 (AZD1222)Biological

    Vaccination with reduced dose (half dose) of ChAdOx1 nCoV-19 (AZD1222), in a 2-dose schedule with an interval of 8 weeks, including all adults aged 18 to 49 years, from non-priority groups, from Viana city - Espírito Santo (ES)/Brazil.

  • Standard dose of ChAdOx1 nCoV-19 (AZD1222)Biological

    Vaccination with standad dose of ChAdOx1 nCoV-19 (AZD1222), in a 2-dose schedule with an interval of 8 weeks, in external cohort of health workers aged 18 to 49 years.

Study groups in NCT05059106
Study groupRoleWhat they receive
Group 1ExperimentalHalf dose of ChAdOx1 nCoV-19 (AZD1222) ) in a 2-dose schedule with an interval of 8 weeks.
Receives: Biological: Half dose of ChAdOx1 nCoV-19 (AZD1222)
Group 2Active comparatorStandad dose of ChAdOx1 nCoV-19 (AZD1222) in a 2-dose schedule with an interval of 8 weeks.
Receives: Biological: Standard dose of ChAdOx1 nCoV-19 (AZD1222)

What is being measured

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

  1. Incidence of new cases

    Incidence of new cases over 12 months following treatment

    Measured: 12 months

Secondary outcomes (12)

  1. Number of deaths

    Number of deaths with specific ICD for covid-19

    Measured: 12 months

  2. number of hospital admissions

    number of hospital admissions for covid-19

    Measured: 12 months

  3. number of intensive care unit (ICU) admissions

    number of intensive care unit (ICU) admissions for the treatment of SARS

    Measured: 12 months

  4. number of tests (RT-PCR)

    number of tests (RT-PCR) performed and positive

    Measured: 12 months

  5. Viral Neutralization Assay

    Neutralizing antibody titers will be expressed by the ability of antibodies to neutralize up to 50% the number of plaques (PRNT50). Title > 1:50 will be considered positive.

    Measured: 4 and 8 months

  6. serological assay

    Serological test by chemiluminescence. Results are expressed in U/mL and data interpretation will be done as follows: <0.8 U/mL = non-reactive sample; ≥0.8 U/mL = reactive sample.

    Measured: 8 and 10 months

  7. IgM

    Determination of specific IgM profile. Results will be expressed in fluorescence intensity or pg/ml.

    Measured: 8 and 10 months

  8. IgG

    Determination of specific IgG profile. Results will be expressed in fluorescence intensity or pg/ml.

    Measured: 8 and 10 months

  9. systemic soluble factors

    Dosage of soluble systemic factors (chemokines, cytokines and growth factors). Results will be expressed in pg/ml.

    Measured: 8 and 10 months

  10. Antigen-specific stimulation of peripheral blood mononuclear cells

    Antigen-specific stimulation of peripheral blood mononuclear cells in vitro. The results will be expressed in percentage positive frequency for a specific cell phenotype.

    Measured: 10 and 12 months

  11. Lymphocyte investigation

    Investigation of memory T and B lymphocytes. The results will be expressed in percentage positive frequency for a specific cell phenotype.

    Measured: 10 and 12 months

  12. Cytokine investigation

    Investigation of intracytoplasmic cytokines. The results will be expressed in percentage positive frequency for a specific cell phenotype.

    Measured: 10 and 12 months

Timeline

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

  1. First posted28 Sep 2021
  2. Study start1 Jun 2021
  3. Primary completion1 Jun 2022 (estimated)
  4. Study completion30 Oct 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 2/3
Primary purpose
Prevention
Allocation
Non-randomised
Intervention model
Sequential
Masking
None (open label)
Enrolment
29,637 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05059106
Sponsor's protocol ID
FUES02
Status last verified
Sep 2021
First submitted
24 Sep 2021
Last updated
28 Sep 2021
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Medeiros-Junior NF, Gouvea MDPG, Camacho LAB, Villela DAM, Lima SMB, Schwarcz WD, Azevedo AS, Neto LFP, Domingues CMAS, Fantoni RNDS, Forechi L, Ruchdeschel T, Albertino LF, Rosi MP, Rizzi RB, Muniz SM, Santos HCD, de Oliveira Roza TL, Oliveira YGP, Dias LH, Miyamoto ST, Tapia KRL, Lyra DGP, Jubini JD, Burian APN, Moulaz IR, Araujo MF, Tort LFL, Oliveira ACA, Oliveira Prado R, Pereira AAS, Miranda VHS, Speziali E, Costa-Pereira C, Alves CC, Carvalho KRA, Dos Santos LM, Oliveira-Carvalho N, Oliveira G, Santos TMAFD, Figueiredo ACC, Costa-Rocha IA, Campi-Azevedo AC, Peruhype-Magalhaes V, Garcia CC, Siqueira MM, Antonelli LRDV, Coelho-Dos-Reis JGA, Teixeira-Carvalho A, Mill JG, Martins-Filho OA, Valim V. Third Booster Half Dose of ChAdOx1-nCov-19 Is Effective, Safe, and Induces Long-Duration Humoral and Cellular Immune Response to Omicron: 1-Year Follow-Up of Viana Study. Vaccines (Basel). 2025 Oct 30;13(11):1113. doi: 10.3390/vaccines13111113.

    PubMed 41295486

Questions about this trial

What is this clinical trial studying?

A Phase 2/3 study testing Half dose of ChAdOx1 nCoV-19 (AZD1222) and Standard dose of ChAdOx1 nCoV-19 (AZD1222) in people with SARS-CoV-2, run by Federal University of Espirito Santo 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 1 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 28 Sep 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 combined phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

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?

Contact Valéria Valim, PhD (+5527999874665, val.valim@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Incidence of new cases (time frame: 12 months). 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 NCT05059106, 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 28 Sep 2021.

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