Safety and Immunogenicity of heterologous or homologous booster after complete vaccination against COVID-19.

Status

Recruiting

Phases

Phase 4

Study type

Interventional

Source

REBEC

Registry ID

RBR-5y9y7p7

Enrollment

Unknown

Registered

2021-12-13

Start date

2021-10-20

Completion date

Unknown

Last updated

2025-10-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Covid19

Interventions

Investigational Product Recombinant covid-19 vaccine (ChAdOx1 nCoV-19) Fiocruz/AstraZeneca Dose: 0.5 mL, containing 5 × 1010 viral particles Via: Intramuscular (deltoid) Covid-19 Pfizer/Wyeth Vaccine

D014614

D022223

D015164

Eligibility

Age

18 Years to No maximum

Inclusion criteria

Inclusion criteria: Age 18 years or older; Have completed the primary vaccination course against COVID-19 with the Coronavac/Butantan, AstraZeneca/Fiocruz or Pfizer vaccines for at least three months; Accepting to participate in the study by signing the Informed Consent Form (ICF);

Exclusion criteria

Exclusion criteria: Uncontrolled chronic illness (defined as illness that required a significant change in therapy or hospitalization for worsening illness during the 3 months prior to inclusion); Individuals with any severe or progressive neurological disorder, difficult to control seizure disorder or a history of Guillian-Barré syndrome or demyelinating diseases of the central nervous system; Individuals with congenital or acquired immunodeficiency*; or individuals who have received treatment with immunosuppressive therapy, including cytotoxic agents or systemic corticosteroids, e.g. eg, for cancer or an autoimmune disease, within the last 12 months or planned receipt during the study period. If a short-term course ( 350 cells/mm3 at the last exam. Criteria for postponing vaccination, with subsequent reassessment, should be considered: Individuals with acute, mild febrile illnesses until they are 72 hours without fever; Individuals diagnosed with COVID-19 within 4 weeks of symptom onset;

Design outcomes

Primary

Measure	Time frame
Expected outcome 1: Increased geometric mean (GMT) of anti-SARS-Cov-2 antibody titers 28 days after a booster dose of COVID-19 vaccine for each study group, measured by assay binding antibody detection of electrochemiluminescence and detection of neutralizing antibodies to SARS-CoV-2.;Expected Outcome 2: Frequency (%) of local and systemic adverse events requested within 7 days after each vaccine dose, for each group of participants.;Expected outcome 4: frequency (%) of serious adverse events throughout the study period for each group of participants.;Expected Outcome 3: Frequency (%) of unsolicited adverse events within 28 days after each vaccine dose, for each group of participants.	—

Measure

Time frame

Expected outcome 1: Increased geometric mean (GMT) of anti-SARS-Cov-2 antibody titers 28 days after a booster dose of COVID-19 vaccine for each study group, measured by assay binding antibody detection of electrochemiluminescence and detection of neutralizing antibodies to SARS-CoV-2.;Expected Outcome 2: Frequency (%) of local and systemic adverse events requested within 7 days after each vaccine dose, for each group of participants.;Expected outcome 4: frequency (%) of serious adverse events throughout the study period for each group of participants.;Expected Outcome 3: Frequency (%) of unsolicited adverse events within 28 days after each vaccine dose, for each group of participants.

—

Secondary

Measure	Time frame
"No secondary outcomes are expected."	—

Countries

Brazil

Contacts

Public ContactJosé Neto

cerbino@fiocruz.br+55(21) 3865-9695

Outcome results

None listed

Source: REBEC (via WHO ICTRP)