NCT05812586

Brief Summary

SARS-CoV-2 is a highly transmissible and pathogenic coronavirus that emerged in late 2019 and has caused a pandemic of acute respiratory disease, collectively known as COVID-19. Given the relatively short duration of protection after vaccination or SARS-CoV-2 infection and the evolution of immune-evading strains, it is likely that the population will have to be repeatedly boosted until a "universal" Pan-Sarbecovirus vaccine is available. SARS-CoV-2 protein subunit vaccine candidates have shown that, despite adjuvantation, their safety/reactogenicity profile seems to be preferable over mRNA or vectored vaccines, whilst inducing non-inferior immune responses (1,2). In this regard, serious adverse events of special interest from mRNA vaccines seem to be have been substantially underestimated/underreported. In a preliminary analysis by an International consortium, the true incidence seems to be 1,250/million excess risk in vaccinees instead of the 1-2/million reported by the Department of Health and Human Services (3,4). Additionally, in a recent study, the Clover SCB-2019 protein subunit vaccine candidate has shown higher neutralizing antibodies titers against the omicron variant, when compared to an inactivated vaccine (data not published yet). Although Brazil has various vaccine platforms authorized for emergency use or licensed, such as mRNA vaccines, vector-based vaccines, inactivated vaccines, so far Brazil has no access to adjuvanted or non-adjuvanted protein-based vaccines. This study will involve two vaccines registered in Brazil and a protein-based adjuvanted vaccine candidate, SCB-2019/Clover. Protein-based adjuvanted vaccines have the advantage of being from a known and licensed technology that can produce high quantities of vaccine at reasonable Costs of Goods. Protein-based adjuvanted vaccines have also been shown to be highly immunogenic, both in the context of COVID-19 (2,5) and other licensed vaccines (6), with long persistence of immunity and protection. Over 80% of the Brazilian population above the age of 18 years have received a full primary vaccination and another 7% at least one dose of vaccine. The overall booster coverage is about 48% (64% of the adults) (7). Anvisa has authorized 1st and 2nd booster doses of various vaccines in line with the MoH policy which was last updated in March 2022. It can be speculated that, like in other geographies, a third booster will be recommended soon, especially to at risk populations and in the scenario of high circulation of the Omicron BA.5 strain. This study will explore the immunogenicity, safety and reactogenicity of a booster dose of various platforms in fully primed individuals regardless of the number of booster doses they have received prior to the enrollment in the study. This mimics the "real world scenario" at vaccination centers where individuals with different background vaccination schemes show up for "a booster". It would facilitate logistics of immunization substantially if vaccines for boosting, independent of the immunization status, could be interchangeable with respect to safety/reactogenicity and immunogenicity. This study will enroll fully-primed individuals (2 doses of either Pfizer mRNA or Oxford/AZ/Fiocruz or Sinovac/Butantan or 1 dose of Janssen vaccine) who have received their last vaccine dose at least 4 months prior to study entry and who have received either no booster, or 1 or 2 boosters. Individuals will be stratified in cohorts by number of boosters and then randomized to receive one of 3 booster vaccines (AstraZeneca/Fiocruz, Pfizer/Wyeth, SCB-2019/Clover).

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
760

participants targeted

Target at P50-P75 for phase_3 covid19

Timeline
Completed

Started Mar 2023

Shorter than P25 for phase_3 covid19

Geographic Reach
1 country

2 active sites

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

March 14, 2023

Completed
23 days until next milestone

First Submitted

Initial submission to the registry

April 6, 2023

Completed
7 days until next milestone

First Posted

Study publicly available on registry

April 13, 2023

Completed
2 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 1, 2023

Completed
3 months until next milestone

Study Completion

Last participant's last visit for all outcomes

September 1, 2023

Completed
Last Updated

April 13, 2023

Status Verified

April 1, 2023

Enrollment Period

3 months

First QC Date

April 6, 2023

Last Update Submit

April 10, 2023

Conditions

Outcome Measures

Primary Outcomes (3)

  • Immunogenicity

    Anti-Spike IgG antibody positivity and titers (ELISA) for SARS-CoV-2 strains (Wuhan and BA.5)

    At baseline (day 0)

  • Immunogenicity

    Anti-Spike IgG antibody positivity and titers (ELISA) for SARS-CoV-2 strains (Wuhan and BA.5)

    At day 28 after booster dose

  • Safety

    Occurrence of SAEs, AESIs and severe unsolicited AEs

    Throughout the study period, an average of 3 months

Secondary Outcomes (3)

  • Immunogenicity

    At days 0, 28 and 84

  • Immunogenicity

    At day 84

  • Safety

    Over days 0-7

Other Outcomes (2)

  • Documentation of confirmed SARS-CoV-2 infection

    At days 28 and 84

  • Additional exploratory immunogenicity

    At days 0, 28 and 84 after booster dose

Study Arms (9)

Group 1: SCB-2019/Clover

EXPERIMENTAL

Cohort A: complete primary immunization, no previous booster dose: SCB-2019/Clover

Biological: SCB-2019/Clover

Group 2: AstraZeneca/Fiocruz

EXPERIMENTAL

Cohort A: complete primary immunization, no previous booster dose: AstraZeneca/Fiocruz

Biological: AstraZeneca/Fiocruz

Group 3: Pfizer/Wyeth

EXPERIMENTAL

Cohort A: complete primary immunization, no previous booster dose: Pfizer/Wyeth

Biological: Pfizer/Wyeth

Group 4: SCB-2019/Clover

EXPERIMENTAL

Cohort B: primary immunization plus one previous booster dose:SCB-2019/Clover

Biological: SCB-2019/Clover

Group 5: AstraZeneca/Fiocruz

EXPERIMENTAL

Cohort B: primary immunization plus one previous booster dose: AstraZeneca/Fiocruz

Biological: AstraZeneca/Fiocruz

Group 6: Pfizer/Wyeth

EXPERIMENTAL

Cohort B: primary immunization plus one previous booster dose: Pfizer/Wyeth

Biological: Pfizer/Wyeth

Group 7: SCB-2019/Clover

EXPERIMENTAL

Cohort C: primary immunization plus two previous booster doses: SCB-2019/Clover

Biological: SCB-2019/Clover

Group 8: AstraZeneca/Fiocruz

EXPERIMENTAL

Cohort C: primary immunization plus two previous booster doses: AstraZeneca/Fiocruz

Biological: AstraZeneca/Fiocruz

Group 9: Pfizer/Wyeth

EXPERIMENTAL

Cohort C: primary immunization plus two previous booster doses: Pfizer/Wyeth

Biological: Pfizer/Wyeth

Interventions

SCB-2019/CloverBIOLOGICAL

SCB-2019/Clover Vaccine

Group 1: SCB-2019/CloverGroup 4: SCB-2019/CloverGroup 7: SCB-2019/Clover

AstraZeneca/Fiocruz Vaccine

Group 2: AstraZeneca/FiocruzGroup 5: AstraZeneca/FiocruzGroup 8: AstraZeneca/Fiocruz
Pfizer/WyethBIOLOGICAL

Pfizer/Wyeth Vaccine

Group 3: Pfizer/WyethGroup 6: Pfizer/WyethGroup 9: Pfizer/Wyeth

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Male or female ≥18 years of age.
  • Individuals are willing and able to comply with study requirements, including all scheduled visits, vaccination, laboratory tests, and other study procedures.
  • Individuals are willing and able to give an informed consent, prior to screening.
  • Individuals must have completed vaccine priming, regardless of vaccine regimen. Primary vaccination and previous booster scheme data will be annotated as patient history.
  • Interval between last dose and current study dose of a minimum of 4 months and a maximum of 24 months (to optimize candidate participation).
  • Healthy participants or participants with pre-existing medical conditions who are in a stable medical condition. A stable medical condition is defined as disease not requiring significant change in therapy or hospitalization for worsening disease during the 3 months before enrollment.
  • Female participants are eligible to participate in the study if not pregnant, not breastfeeding, and at least 1 of the following criteria apply:
  • Women of non-childbearing potential;
  • Women of childbearing potential (WOCBP) must have a negative urine pregnancy test prior to study vaccination. A confirmatory serum pregnancy test may be conducted at the investigator's discretion. They must be using a highly effective licensed method of birth control during the study, until 90 days after the study vaccination.

You may not qualify if:

  • Participants are excluded from the study if any of the following criteria apply:
  • Individuals with fever \>37.5°C (axillary), or any acute illness at baseline (Day 0) or within 3 days prior to randomization. Participants meeting this criterion may be rescheduled within the relevant window. Febrile participants with minor illnesses can be enrolled at the discretion of the investigator.
  • Self-reported confirmed COVID-19 infection, through RT-PCR or lateral flow test, in the last 4 weeks.
  • Individuals who did not complete the primary vaccination scheme for any licensed COVID vaccine or plan to receive another COVID-19 vaccine (other than the study vaccines) during the study period, a drug for COVID-19 prevention or treatment (e.g., drugs, monoclonal antibodies, such as Rituximab or any other anti-CD20 monoclonal antibodies during the study period.).
  • Individuals who have a history of severe adverse reaction associated with a vaccine or severe allergic reaction (e.g., anaphylaxis, venal or arterial thrombosis, thrombocytopenia) to any component of the study vaccines (Pfizer/Wyeth, AstraZeneca/Fiocruz, CpG 1018, aluminum, or SCB-2019 components, as outlined in the latest summary of product characteristics for Pfizer/Wyeth, AstraZeneca/Fiocruz, and the IB for SCB-2019/Clover).
  • Individuals with capillary leakage syndrome or thrombosis with thrombocytopenia syndrome
  • \- TTS (possibly associated with vaccination with the AstraZeneca/Fiocruz vaccine).
  • Individuals who had pericarditis or myocarditis (these pathologies may be associated with the Pfizer/Wyeth vaccine, especially in young men).
  • Individuals with known bleeding disorder that, in the opinion of the investigator, contraindicate intramuscular injection.
  • Individuals who have a history of malignancy within 1 year before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix which have been cured, or other malignancies with minimal risk of recurrence).
  • Individuals with any progressive or severe neurologic disorder, seizure disorder, or history of Guillain-Barré syndrome.
  • Individuals who received treatment with immunosuppressive therapy in the last 90 days, including cytotoxic agents or systemic corticosteroids, or planned receipt during the study period. If a short-term course of systemic corticosteroid immunosuppressive dose has been used for the treatment of acute illness, the participant should not be included in the study until corticosteroid therapy has been discontinued for at least 15 days prior to first study vaccination.
  • Individuals with autoimmune diseases, except: Hashimoto's thyroiditis, vitiligo, psoriasis, lupus discord and alike; HIV-positive individuals and/or on HIV treatment.
  • Individuals who have received any other investigational product within 30 days prior to Day 0 or intend to participate in another clinical study at any time during the conduct of this study.
  • Individuals who have received any other licensed vaccines within 14 days prior to enrollment in this study or who are planning to receive any vaccine up to 28 days after the last vaccination.
  • +5 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

Centro de Estudos e Pesquisas em Moléstias Infecciosas - CEPCLIN

Natal, Rio Grande do Norte, 59025-050, Brazil

Location

Centro de Referência para Imunobiológicos Especiais - CRIE - UNIFESP

São Paulo, 04038-001, Brazil

Location

Related Publications (1)

  • Ann Costa Clemens S, Weckx L, Milan EP, Smolenov I, Clemens R. Interchangeability of different COVID-19 vaccine platforms as booster doses: A phase 3 study mimicking real-world practice. Vaccine. 2024 Jul 25;42(19):3989-3998. doi: 10.1016/j.vaccine.2024.05.009. Epub 2024 May 17.

MeSH Terms

Conditions

COVID-19

Condition Hierarchy (Ancestors)

Pneumonia, ViralPneumoniaRespiratory Tract InfectionsInfectionsVirus DiseasesCoronavirus InfectionsCoronaviridae InfectionsNidovirales InfectionsRNA Virus InfectionsLung DiseasesRespiratory Tract Diseases

Study Officials

  • Sue Ann C Clemens, MD, phD

    University of Oxford

    STUDY CHAIR

Study Design

Study Type
interventional
Phase
phase 3
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Masking Details
The participants of this study will be blinded as to the vaccine booster they receive.
Purpose
PREVENTION
Intervention Model
PARALLEL
Model Details: Exploratory phase 3, cohort randomized, single-blind, multi-center study
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

April 6, 2023

First Posted

April 13, 2023

Study Start

March 14, 2023

Primary Completion

June 1, 2023

Study Completion

September 1, 2023

Last Updated

April 13, 2023

Record last verified: 2023-04

Locations