Study on Effectiveness of 2-dose Live Attenuated Varicella Vaccine

Study Overview
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Brief Summary
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The objective of the study is as follows: To know the antibody level during different interval after received 1 dose varicella vaccine. To know safety and effectiveness of received 2 doses varicella vaccine with different interval. To know safety and effectiveness of received varicella vaccine and MMR at the same time. To achieve that, this study selects children with specific varicella vaccine history, gives 1 or 2 doses varicella vaccine, collects blood specimens and makes a follow-up visit after vaccination. All blood specimens will be tested by a third-party detection institution.

Official Title
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Study on Effectiveness of 2-dose Live Attenuated Varicella Vaccine

Conditions
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Varicella

Intervention / Treatment
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* Biological: 2 doses with an 3 months interval
* Biological: A second dose with an 1 year interval
* Biological: A second dose with an 3 year interval
* Biological: A second dose with an 5 year interval
* Biological: 1 dose Varicella vaccine and 1 dose MMR given at the same time
* Biological: 1 dose MMR


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 1 to 7 Without a previous history of varicella With an axillary temperature ≤37.5℃ at the time of vaccination Appropriate varicella vaccination history With guardian signing the informed consent and available for clinical observation Exclusion Criteria: Hypersensitive to any active substance of the vaccine including excipients and antibiotics With acute illness, severe or acute attack of chronic illness or fever With immunodeficiency or weakened immune system or being treated with immunosuppressant drugs Suffering a brain disease, uncontrolled epilepsy or progressive nerve system disease With a family or personal history of seizure, chronic illness, epilepsy or allergy With unknown immunization history or unable to follow the immunization schedule of EPI Received any vaccine within 4 weeks or willing to receive any vaccine in 1 month With hemorrhagic tendency or prolonged period of bleeding Received whole blood, plasma or immunoglobulin within 5 months Received systemic antibiotics or antiviral treatment for acute illness within 7 days With an axillary temperature ≥38℃ within 3 days Participating in another clinical trial Any situation that might influence the consequence of the clinical trial

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: None varicella vaccine history<br>2 doses with an 3 months interval | Biological: 2 doses with an 3 months interval<br>* varicella vaccination<br>|
| Experimental: 1 year after first dose<br>A second dose with an 1 year interval | Biological: A second dose with an 1 year interval<br>* varicella vaccine<br>|
| Experimental: 3 years after first dose<br>A second dose with an 3 year interval | Biological: A second dose with an 3 year interval<br>* varicella vaccine<br>|
| Experimental: 5 years after first dose<br>A second dose with an 5 year interval | Biological: A second dose with an 5 year interval<br>* varicella vaccine<br>|
| Experimental: Testing group for conbined immunization<br>1 dose Varicella vaccine and 1 dose MMR given at the same time | Biological: 1 dose Varicella vaccine and 1 dose MMR given at the same time<br>* varicella vaccine and MMR<br>|
| Placebo Comparator: Control group for conbined immunization<br>1 dose MMR | Biological: 1 dose MMR<br>* MMR<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion rate and GMCs after varicella vaccination |  | 35-42 days after each dose vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of Adverse Events Following Immunization |  | 30 days after each dose vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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varicella vaccination