Immunogenicity and Safety of Fractional Booster Dose of COVID-19 Vaccines Available for Use in Pakistan/Brazil: A Phase 4 Dose-optimizing Trial
COVID-19
About this trial
This is an interventional prevention trial for COVID-19 focused on measuring Fractional dose, COVID-19
Eligibility Criteria
Inclusion Criteria:
- Healthy male or female individuals aged 18 years to 60 years
- Participant is willing and able to give written informed consent for participation in the trial
- Individuals who can comply with trial procedures and are available for the duration of follow-up.
Brazil:
● Previous vaccination with a complete primary series of Sinovac (Priming Group 1), AZD1222 (Priming Group 2), or BNT162b2 (Priming Group 3-B) at least 6 months prior to screening
Pakistan:
● Previous vaccination with a complete primary series of Sinovac (Priming Group 1) or AZD1222 (Priming Group 2) at least 6 months prior to screening, or PCR-confirmed natural infection (Priming Group 3-P) between February 2021 - 6 months prior to screening
Exclusion Criteria:
- Has a contraindication to BNT162b2, AZD1222 or Sinovac
- Has received an incomplete primary COVID-19 vaccination series
- Has received 3 doses of COVID-19 vaccine
- Has received heterologous primary COVID-19 vaccination series
- History of a solid organ or bone marrow transplant
- History of malignancy (other than non-melanoma skin cancer) within the past five years
- Currently on hemodialysis
- Any confirmed or suspected immunosuppressive or immunodeficiency condition or diagnosis
- On chronic (>30 days) use of immunosuppressive medications at the time of enrollment (except topical steroids or short-term oral steroids, i.e., ≤14 days)
- Known diagnosis of HIV with CD4 count <200 cells/mm3 (in the past 6 months)
- Active or history of previous auto-immune neurological disorders (e.g., multiple sclerosis, Guillain-Barre syndrome, transverse myelitis) (excluding Bell's palsy)
- Has received anti-CD20 monoclonal antibodies for any reason in the past 12 months
- Has received monoclonal antibodies to treat a previous COVID-19 event
- Pregnant at screening
- Positive SARS-CoV-2 Antigen test in respiratory specimen at screening
- Planning to migrate out of the study area within 6 months of the enrollment
- Participants currently enrolled in any other COVID-19 vaccine research trial in which they are getting a COVID-19 vaccine during the study period
- Illiterate individuals (Brazil only)
- Has a severe and/or uncontrolled comorbidity
Pakistan (natural infection Priming Group (Priming Group 3-P)):
● Prior vaccination with ANY vaccine against COVID-19
Sites / Locations
- FIOCRUZ
- Aga Khan University Clinical Trials UnitRecruiting
Arms of the Study
Arm 1
Arm 2
Arm 3
Arm 4
Arm 5
Arm 6
Arm 7
Arm 8
Arm 9
Arm 10
Arm 11
Arm 12
Arm 13
Arm 14
Arm 15
Arm 16
Arm 17
Arm 18
Arm 19
Experimental
Active Comparator
Experimental
Experimental
Active Comparator
Active Comparator
Experimental
Active Comparator
Experimental
Experimental
Active Comparator
Experimental
Active Comparator
Experimental
Experimental
Active Comparator
Experimental
Experimental
Active Comparator
Priming Group 1: Sinovac Prime, AZD1222 ½ dose (Brazil only)
Priming Group 1: Sinovac Prime, AZD1222 full dose (Brazil only)
Priming Group 1: Sinovac Prime, BNT162b2 1/3 dose
Priming Group 1: Sinovac Prime, BNT162b2 1/2 dose
Priming Group 1: Sinovac Prime, BNT162b2 full dose
Priming Group 1: Sinovac Prime, Sinovac full dose
Priming Group 2: AZD1222 Prime, AZD1222 ½ dose (Brazil only)
Priming Group 2: AZD1222 Prime, AZD1222 full dose (Brazil only)
Priming Group 2: AZD1222 Prime, BNT162b2 1/3 dose
Priming Group 2: AZD1222 Prime, BNT162b2 1/2 dose
Priming Group 2: AZD1222 Prime, BNT162b2 full dose
Priming Group 3-B: BNT162b2 Prime, AZD1222 ½ dose (Brazil only)
Priming Group 3-B: BNT162b2 Prime, AZD1222 full dose (Brazil only)
Priming Group 3-B: BNT162b2 Prime, BNT162b2 1/3 dose (Brazil only)
Priming Group 3-B: BNT162b2 Prime, BNT162b2 1/2 dose (Brazil only)
Priming Group 3-B: BNT162b2 Prime, BNT162b2 full dose (Brazil only)
Priming Group 3-P: Natural Infection Prime, BNT162b2 1/3 dose (Pakistan only)
Priming Group 3-P: Natural Infection Prime, BNT162b2 1/2 dose (Pakistan only)
Priming Group 3-P: Natural Infection Prime, BNT162b2 full dose (Pakistan only)