Immunogenicity and Safety of 2 Doses of Live Attenuated Varicella Vaccine

Study Overview
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Brief Summary
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The purpose of this study is to observe the occurrence of adverse events, seroconversion rate and geometric mean titres(GMTs) of 2 doses of live attenuated varicella vaccine.

Official Title
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A Study to Evaluate the Immunogenicity and Safety of 2 Doses of Live Attenuated Varicella Vaccine

Conditions
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Varicella

Intervention / Treatment
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* Biological: varicella-1
* Biological: varicella-3
* Biological: varicella-5


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Parent/legal acceptable representative is willing and able to understand the protocol requirements and provide informed consent Participant is aged ≥ 1 year to ≤ 7 years Participant without preventive inoculation of varicella vaccine and previous history of chickenpox and zoster Subject and parent/guardian able to attend all scheduled visits and comply with all trial procedures Body temperature ≤ 37.5℃ Exclusion Criteria: Known allergy to any constituent of the vaccine Known acute illness, severe chronic disease, acute exacerbation of chronic disease and fever Known or suspected impairment of immunologic function, or receipt of immunosuppressive therapy or immunoglobulin since birth Reported the history of allergies, convulsions, epilepsy, mental illness and brain disease and clear serious systemic reaction Failed to the Expanded Programme on Immunization(EPI) Receipt of any vaccine in the 4 weeks preceding the trial vaccination Plan to receive any vaccine in the 4 weeks following the trial vaccination Known bleeding disorder Receipt of whole blood, blood plasma or immunoglobulin in the 5 months preceding the trial vaccination Reported the history of acute illness had need systemic antibiotics or antiviral treatment of infections in the 7 days preceding the trial vaccination An acute illness with or without fever (temperature ≥ 38.0℃) in the 3 days preceding enrollment in the trial Participation in any other interventional clinical trial Any condition which, in the opinion of the investigator, would pose a health risk to the subject or interfere with the vaccine

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 7 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: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: varicella-1<br>The second varicella vaccine and 1 year of the interval time between 2 doses | Biological: varicella-1<br>* Give the second varicella vaccine (a single 0.5 ml) and get blood samples at 0, 35-42 day<br>|
| Experimental: varicella-3<br>The second varicella vaccine and 3 years of the interval time between 2 doses | Biological: varicella-3<br>* Give the second varicella vaccine (a single 0.5 ml) and get blood samples at 0, 35-42 day<br>|
| Experimental: varicella-5<br>The second varicella vaccine and 5 years of the interval time between 2 doses | Biological: varicella-5<br>* Give the second varicella vaccine (a single 0.5 ml) and get blood samples at 0, 35-42 day<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion rate and GMTs for live attenuated varicella vaccine |  | 35-42 days after the second dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of adverse events |  | within 30 days after the second dose |