A Study to Evaluate Safety and Immunogenicity of Inactivated SARS-CoV-2 Vaccine (Vero Cells) in Healthy Population Aged 18 Years and Above(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 adults ⩾18 years.

Official Title
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Evaluation of the Safety and Immunogenicity of Inactivated SARS-CoV-2 Vaccine (Vero Cells) in Healthy Population Aged 18 Years and Above: a Randomized, Double-blind, Placebo Parallel-controlled Phase II Clinical Trial

Conditions
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COVID-19

Intervention / Treatment
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* Biological: medium dosage inactivated SARS-CoV-2 vaccine
* Biological: high dosage inactivated SARS-CoV-2 vaccine
* Biological: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy permanent residents aged 18 years and above; Subjects agree to sign the informed consent forms voluntarily; Subjects are able to comply with the requirements of the clinical trial protocol; Armpit temperature <= 37.0 degrees C; Female subjects of childbearing age were not pregnant at the time of enrollment, were not breastfeeding, and had no birth plan within the first 3 months after enrollment; effective contraceptive measures had been taken within 2 weeks before enrollment. 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; Positive in SARS-CoV-2 antibody test; Subjects with 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; Subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; 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, uncontrollable hypertension (systolic pressure >=140 mmHg, diastolic pressure >= 90 mmHg; subjects aged >= 60 years with systolic pressure >=150 mmHg, diastolic pressure >=100 mmHg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; Subjects diagnosed with congenital or acquired immune deficiency, HIV infection, lymphoma, leukemia or other autoimmune diseases; Subjects with 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: 18 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: medium dosage on day 0, 14(18 59 years)<br>Two doses of medium dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,14 | Biological: medium dosage inactivated SARS-CoV-2 vaccine<br>* medium dosage<br>|
| Experimental: high dosage on day 0, 14(18 59 years)<br>Two doses of high dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,14 | Biological: high dosage inactivated SARS-CoV-2 vaccine<br>* high dosage<br>|
| Placebo Comparator: placebo on day 0, 14(18 59years)<br>Two doses of placebo on the schedule of day 0,14 | Biological: Placebo<br>* placebo<br>|
| Experimental: medium dosage on day 0, 28(18 59 years)<br>Two doses of medium dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,28 | Biological: medium dosage inactivated SARS-CoV-2 vaccine<br>* medium dosage<br>|
| Experimental: high dosage on day 0, 28(18 59 years)<br>Two doses of high dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,28 | Biological: high dosage inactivated SARS-CoV-2 vaccine<br>* high dosage<br>|
| Placebo Comparator: placebo on day 0, 28(18 59years)<br>Two doses of placebo on the schedule of day 0,28 | Biological: Placebo<br>* placebo<br>|
| Experimental: medium dosage on day 0, 28, 56(18 59 years)<br>Three doses of medium dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,28,56 | Biological: medium dosage inactivated SARS-CoV-2 vaccine<br>* medium dosage<br>|
| Experimental: high dosage on day 0, 28, 56(18 59 years)<br>Three doses of high dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,28,56 | Biological: high dosage inactivated SARS-CoV-2 vaccine<br>* high dosage<br>|
| Placebo Comparator: placebo on day 0, 28, 56(18 59 years)<br>Three doses of placebo on the schedule of day 0,28,56 | Biological: Placebo<br>* placebo<br>|
| Experimental: medium dosage on day 0, 28, 56(>59 years)<br>Three doses of medium dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,28,56 | Biological: medium dosage inactivated SARS-CoV-2 vaccine<br>* medium dosage<br>|
| Experimental: high dosage on day 0, 28, 56(>59 years)<br>Three doses of high dosage inactivated SARS-CoV-2 vaccine on the schedule of day 0,28,56 | Biological: high dosage inactivated SARS-CoV-2 vaccine<br>* high dosage<br>|
| Placebo Comparator: placebo on day 0, 28, 56(>59 years)<br>Three doses of placebo on the schedule of day 0,28,56 | Biological: Placebo<br>* placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The seropositive rates of SARS-CoV-2 neutralizing antibody |  | Day 28 post full vaccination | 
| The seropositive level of SARS-CoV-2 neutralizing antibody |  | Day 28 post full vaccination | 
| The seropositive rates of SARS-CoV-2 IgG antibody (tested by ELISA) |  | Day 28 post full vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of adverse reactions/events |  | 0-28 days after each dose of vaccination | 
| Serious Adverse Events (SAE) |  | within 12 months post full vaccination | 
| Level of SARS-CoV-2 IgG antibody (tested by ELISA) |  | Day 28 post full vaccination | 
| The seropositive rates of SARS-CoV-2 neutralizing antibody |  | Day 28 after the second dose of the 3 doses group, day 14 after the full immunization of the 2 doses group, and 3, 6 and 12 months post full vaccination of all groups | 
| The seropositive rates of SARS-CoV-2 IgG antibody (tested by ELISA) |  | Day 28 after the second dose of the 3 doses group, day 14 after the full immunization of the 2 doses group, and 3, 6 and 12 months post full vaccination of all groups | 
| The seropositive level of SARS-CoV-2 neutralizing antibody |  | Day 28 after the second dose of the 3 doses group, day 14 after the full immunization of the 2 doses group, and 3, 6 and 12 months post full vaccination of all groups | 
| The seropositive level of SARS-CoV-2 IgG antibody (tested by ELISA) |  | Day 28 after the second dose of the 3 doses group, day 14 after the full immunization of the 2 doses group, and 3, 6 and 12 months post full vaccination of all groups |