Study of Inactivated SARS-CoV-2 Vaccine (Vero Cells) in Healthy Population Aged 3 to 17 Years(COVID-19)

Study Overview
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Brief Summary
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This study is a randomized, double-blinded, and placebo controlled phase Ⅱ clinical trial of the SARS-CoV-2 inactivated vaccine to evaluate the safety and immunogenicity of the experimental vaccine in healthy population aged 3 to 17 years.

Official Title
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A Randomized, Double-blind, Placebo-controlled Phase Ⅱ Clinical Study to Evaluate the Safety and Immunogenicity of Inactivated SARS-CoV-2 Vaccine (Vero Cells) in Healthy Population Aged 3 to 17 Years

Conditions
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COVID-19

Intervention / Treatment
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* Biological: SARS-CoV-2 Vaccine (Vero Cells), Inactivated
* Biological: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy residents aged 3 to 17 years at the time of consent Subjects and/or their guardian agree to sign the informed consent forms voluntarily. Be able to comply with study requirements/procedures. Axillary temperature ≤ 37.0℃ Exclusion Criteria: Within 14 days before vaccination, subjects have been abroad and to villages/communities experienced COVID-19 epidemics, and in contact with COVID-19 cases or suspected cases. Subjects are under isolation observation, or living in the villages/communities with COVID-19 cases or suspected cases; Confirmed cases, suspected cases or asymptomatic cases with COVID-19 (refer to Information System of China Disease Prevention and Control); Subjects with history of SARS virus infection by self-reported; Positive in throat swab through RT-PCR; History of vaccination of various COVID-19 vaccines or positive in SARS-CoV-2 antibody test; Positive urine pregnancy test for females with menarche History of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated SARS-CoV-2 vaccine; History or family history of convulsion, epilepsy, encephalopathy or mental illness; Subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; Subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, drug-uncontrollable hypertension, diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; Diagnosed with congenital or acquired immunodeficiency, HIV infection, lymphoma, leukemia or other autoimmune diseases; History of coagulation dysfunction (e.g. Coagulation factor deficiency, coagulation disease); Subjects receiving anti-TB treatment; Subjects receiving other research drugs within 6 months before vaccination; Subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); Subjects receiving blood products within 3 months before administration; Subjects vaccinated with live attenuated vaccine within 14 days before vaccination; Subjects vaccinated with other vaccine within 7 days before vaccination; The researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.

Ages Eligible for Study
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Minimum Age: 3 Years
Maximum Age: 17 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: candidate vaccine<br> | Biological: SARS-CoV-2 Vaccine (Vero Cells), Inactivated<br>* 2 doses of SARS-CoV-2 Vaccine (Vero Cells), Inactivated with a 28-day interval constitute a primary immunization course. The third dose on 6 months after primary course is the booster dose. Administer as an intramuscular injection into the lateral deltoid of the upper arm.<br>|
| Placebo Comparator: Placebo<br> | Biological: Placebo<br>* 2 doses of Placebo should be administered as an intramuscular injection into the lateral deltoid of the upper arm with a 28-day interval.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion rate of SARS-CoV-2 neutralizing antibody |  | 28 days post full primary immunization course | 
| Geometric mean titer of SARS-CoV-2 neutralizing antibody |  | 28 days post full primary immunization course | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of adverse reactions/events |  | 0-28 days after each vaccination | 
| Serious Adverse Events (SAE) |  | within 12 months post full primary immunization course and the booster dose respectively | 
| Seroconversion rate of SARS-CoV-2 IgG binding antibody |  | 28 days post full primary immunization course | 
| Geometric mean titer of SARS-CoV-2 IgG binding antibody |  | 28 days, 3 months, 6 months and 12 months post full primary immunization course | 
| Geometric mean titer of SARS-CoV-2 IgG binding antibody |  | 28 days, 3 months, 6 months and 12 months after the booster dose | 
| Geometric mean titer of SARS-CoV-2 neutralizing antibody |  | 3 months, 6 months and 12 months post full primary immunization course | 
| Geometric mean titer of SARS-CoV-2 neutralizing antibody |  | 28 days, 3 months, 6 months and 12 months after the booster dose | 
| Seropositive rate of SARS-CoV-2 neutralizing antibody |  | 3 months, 6 months and 12 months post full primary immunization course | 
| Seropositive rate of SARS-CoV-2 neutralizing antibody |  | 28 days, 3 months, 6 months and 12 months after the booster dose | 
| Seropositive rate of SARS-CoV-2 IgG binding antibody |  | 3 months, 6 months and 12 months post full primary immunization course | 
| Seropositive rate of SARS-CoV-2 IgG binding antibody |  | 28 days, 3 months, 6 months and 12 months after the booster dose |