Covid19
Conditions
Brief summary
Objectives To assess the reactogenicity, measure the adaptive immune responses and track the long-term immune memory in healthy children and adults as well as pediatric patients receiving the COVID-19 vaccines-BNT162b2, CoronaVac-chosen by the Hong Kong Government; to compare the reactogenicity and immunogenicity across the vaccines used for these children and adults. Hypothesis to be tested The safety profile and the magnitude and durability of immune responses to the COVID-19 vaccines in children are non-inferior to those in adults. Design and subjects A single-site, comparative nonrandomised clinical trial for 450 healthy individuals or patients under 18 years old and one or both healthy parents and unrelated adults to receive one of COVID-19 vaccines by intramuscular injection (and intradermal injection) Instruments Mobile app for subjects to record adverse effects, enzyme-linked immunosorbent assay, plaque reduction neutralization assay, luciferase immunoprecipitation system assay and flow cytometry. Interventions BNT162b2 and CoronaVac, by intramuscular or intradermal route Main outcome measures Types and frequencies of adverse effects within 7 days, and changes and peaks of antibody levels and antigen-specific memory T cell responses for 3 years.
Interventions
BIOLOGICALTozinameran
mRNA vaccine developed by BioNTech against COVID-19
BIOLOGICALCoronaVac
Inactivated virus vaccine developed by SinoVac against COVID-19, intramuscular
BIOLOGICALCoronaVac, intradermal
Inactivated virus vaccine developed by SinoVac against COVID-19, intradermal
Sponsors
The University of Hong Kong
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
0 Years to 100 Years
Healthy volunteers
Yes
Inclusion criteria
1. informed consent from the parents or a legally acceptable representative for an underage participant 2. biological parents of students enrolled in the trial or unrelated healthy adults 3. ability to adhere to the follow-up schedules 4. willingness to report reactogenicity daily for 7 days post dose 1, 2 and 3 (and 4) proactively 5. willingness to receive that vaccine available for that particular recruitment period (as student-parent pair, if applicable) 6. good past health, including pre-existing clinically stable disease, such as paediatric or immune disorders 7. prior COVID-19 (for COVID-19 survivor subgroup)
Exclusion criteria
1\. reported pregnancy or breastfeeding
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Adverse reactions | 7 days post-doses 1, 2 and 3 (and 4) | Percentage of occurrence, types, duration and severity of adverse reactions occurring within 7 days |
| Binding antibody response | 1 month post-dose 1, and 1, 6, 18, and 36 months post-dose 3 (and 2 weeks after dose 4) | Geometric mean levels of SARS-CoV2 S and S-RBD-specific binding antibody and related markers as determined by Enzyme-linked Immunosorbent Assay |
| Neutralizing antibody response | 1 month post-dose 1, and 1, 6, 18, and 36 months post-dose 3 (and 2 weeks after dose 4) | Geometric mean levels and geometric mean fold rise of SARS-CoV2 neutralizing antibodies as determined by plaque reduction neutralization assay and surrogate assays |
| T cell response | 1 month post-dose 1, and 1, 6, 18, and 36 months post-dose 3 (and 2 weeks after dose 4) | Geometric mean percentage of CD4 and CD8 T cells specific to SARS-CoV2 S (and N and M) protein |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Adverse events | Throughout the study period, until 36 months post-dose 3/4 | Percentage of occurrence, types, duration and severity of adverse events and severe adverse events throughout study period |
| Binding anti-N antibody response | 1 month post-dose 1, and 1, 6, 18, and 36 months post-dose 3 (and 2 weeks after dose 4) | Geometric mean levels and geometric mean fold rise of SARS-CoV2 N-specific binding antibody as determined by Enzyme-linked Immunosorbent Assay in Arm C participants receiving CoronaVac |
| Vaccine breakthrough | Throughout the study period, until 36 months post-dose 3/4 | Incidence of COVID-19 in participants throughout study period as self-reported or as determined by Luciferase Immunoprecipitation Systems assay/ELISA |
Countries
China
Outcome results
None listed