A Follow-up Study for a Phase III, Efficacy Trial in Inactivated Enterovirus Type 71 (EV71) Vaccine

Study Overview
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Brief Summary
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The purpose of this follow-up study is to evaluate the two-year efficacy, immunogenicity and safety of EV71 Vaccines in preventing Hand, Foot and Mouth disease caused by EV71 in a total 10,000 healthy infants volunteers aged from 6 to 35months old.

Detailed Description
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The phase III, efficacy trial of inactivated vaccine (vero cell) against EV71 has completed on March 2013 in China. The data from the phase III study suggested that the inactivated EV71 vaccine had protection effects on healthy Chinese infants against Hand, Foot and Mouth disease caused by EV71 within one-year surveillance period, and had clinically acceptable safety and good one-year immune persistence. This study is the phase III, open-labelled, follow-up research, in order to evaluate the two-year efficacy, safety and immune persistence.

Official Title
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An Open-labelled, Multicentered, Follow-up Study for a Phase III, Efficacy Trial to Evaluate the Two-year Efficacy, Safety, and Immune Persisitence of Inactivated Enterovirus Type 71 (EV71) Vaccine

Conditions
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Hand, Foot and Mouth Disease

Intervention / Treatment
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* Biological: EV71 vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All subjects vaccinated at least one injection of EV71 vaccine or the placebo in the phase III efficacy trial. Exclusion Criteria: subjects who refuse to continue in the study.

Ages Eligible for Study
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Minimum Age: 6 Months
Maximum Age: 35 Months

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| EV71 Vaccine<br>Inactivated vaccine (vero cell) against EV71 of 400U /0.5ml in 5000 infants aged 6-35 months old on day0,28 | Biological: EV71 vaccine<br>* inactivated vaccine (vero cell) against EV71 of 400U /0.5ml, two doses, 28 days interval<br>|
| Placebo<br>placebo in 5000 infants aged 6-35 months old on day0,28 | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence rate of Hand, Foot and Mouth disease caused by EV71 within the second year observation period after the second vaccination | to evaluate the efficacy of EV71 vacccine against HFMD caused by EV71 | Within the second year after the second vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The GMT of anti-EV71 antibodies in serum two years after second vaccination | to evaluate the immune persistence of anti-EV71 antibodies in serum | 26 months after second vaccination | 
| Frequency of serious adverse events (SAEs) with the second year after the second vaccination | Frequency of serious adverse events in healthy infants during the oney-year follow-up period | within the second year after the second vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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EV71 vaccine, EV71-associated HFMD, efficacy, safety, immune persistence