Safety of an Inactivated SARS-CoV-2 Vaccine (CoronaVac) in Children and Adolescents

Study Overview
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Brief Summary
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This study is a randomized, double-blinded, placebo-controlled, phase Ⅱb clinical trial of an inactivated SARS-CoV-2 vaccine (CoronaVac) manufactured by Sinovac Life Sciences Co. , Ltd.The purpose of this study is to evaluate the safety of the SARS-CoV-2 Inactivated vaccine in healthy children and adolescents aged 3-17 years.

Detailed Description
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This study is a randomized, double-blinded, placebo-controlled,phase Ⅱb clinical trial in children and adolescents aged 3-17 years. The experimental vaccine and placebo were both manufactured by Sinovac Life Sciences Co. , Ltd. A total of 500 subjects will be enrolled, including 100 children aged 3-5 years, 200 children aged 6-11 years and 200 adolescents aged 12-17 years. Each age group will be randomly divided into two groups in a 3:1 ratio and received two doses of experimental vaccine or placebo on on day 0 and day 28.

Official Title
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A Randomized, Double-Blinded, Placebo-Controlled, Phase Ⅱb Clinical Trial, to Evaluate the Safety of the Inactivated SARS-CoV-2 Vaccine (Vero Cell) in Healthy Population Aged From 3 to 17 Years.

Conditions
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COVID-19

Intervention / Treatment
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* Biological: SARS-CoV-2 Inactivated Vaccine
* Biological: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy children and adolescents aged 3-17 years; The subjects and/or guardians can understand and voluntarily sign the informed consent form (For subjects aged 8-17 years, both subjects and guardians need to sign the informed consent form); Proven legal identity. Exclusion Criteria: Travel history / residence history of communities with case reports within 14 days; History of contact with a SARS-CoV-2 infection (positive in nucleic acid test) within 14 days; Have contacted patients with fever or respiratory symptoms from communities with case reports within 14 days; Two or more cases of fever and / or respiratory symptoms in a small contact area of volunteers, such as home, office etc. within 14 days; History of SARS-CoV-2 infection; History of asthma, history of allergy to the vaccine or vaccine components, or serious adverse reactions to the vaccine, such as urticaria, dyspnea, and angioedema; Congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; Autoimmune disease or immunodeficiency / immunosuppression; Severe chronic diseases, severe cardiovascular diseases, hypertension and diabetes that cannot be controlled by drugs, liver or kidney diseases, malignant tumors, etc.; Severe neurological disease (epilepsy, convulsions or convulsions) or mental illness; Thyroid disease or history of thyroidectomy, spleenlessness, functional spleenlessness, spleenlessness or splenectomy resulting from any condition; Diagnosed abnormal blood coagulation function (eg, lack of blood coagulation factors, blood coagulopathy, abnormal platelets) or obvious bruising or blood coagulation; Immunosuppressive therapy, cytotoxic therapy, inhaled corticosteroids (excluding allergic rhinitis corticosteroid spray therapy, acute noncomplicated dermatitis superficial corticosteroid therapy) in the past 6 months; History of alcohol or drug abuse; Acute diseases or acute exacerbation of chronic diseases in the past 7 days; Receipt of blood products within in the past 3 months; Receipt of other investigational drugs in the past 30 days; Receipt of attenuated live vaccines in the past 14 days; Receipt of inactivated or subunit vaccines in the past 7 days; Axillary temperature >37.0°C; Already pregnant (including a positive urine pregnancy test) or are breastfeeding, planning to get pregnant within 3 months; According to the investigator's judgment, the subject has any other factors that are not suitable for participating in the 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: Experimental Group<br>Participant will receive two doses of medium dosage inactivated SARS-CoV-2 vaccine . Vaccine will given by intramuscular injection on day 0 and day 28. | Biological: SARS-CoV-2 Inactivated Vaccine<br>* 600SU inactivated virus in 0·5 mL of aluminium hydroxide solution per injection<br>* Other names: CoronaVac;|
| Placebo Comparator: Control Group<br>Placebo will receive two doses of placebo. The placebo will given by intramuscular injection on day 0 and day 28. | Biological: Placebo<br>* aluminium hydroxide solution only<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety index-incidence of adverse reactions | Incidence rate of adverse reactions occured from the beginning of the vaccination to 28 days after the second dose. | Day 0-28 after each dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety index-incidence of adverse reactions | Incidence rate of adverse reactions within 7 days after each dose | Day 0-7 after each dose vaccination | 
| Safety index-incidence of serious adverse events | Incidence rate of serious adverse events from the beginning of the vaccination to 6 months after the second dose vaccination. | From the beginning of the vaccination to 6 months after the second dose vaccination |