A Study of 2 Doses of VAQTA™ in Healthy Children 12 to 23 Months of Age (V251-069)

Study Overview
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Brief Summary
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This study will demonstrate the immunogenicity and evaluate the safety/tolerability of the vaccine in Chinese children between 12 and 23 months of age.

Official Title
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A Phase III Open-Label Study of Immunogenicity, Safety, and Tolerability of 2 Doses of VAQTA™ (Formalin, Inactivated, Alum-Adjuvanted Hepatitis A Vaccine) in Healthy Children 12 to 23 Months of Age

Conditions
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Hepatitis A Virus Infection

Intervention / Treatment
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* Biological: Hepatitis A Vaccine, Purified Inactivated (VAQTA™)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy Chinese children 12 to 17 months old at receipt of the first study vaccination Exclusion Criteria: Subject is Hepatitis A virus antibody positive at screening or has a history of Hepatitis A infection Subject has a fever 72 hours prior to first injection Subject has already been vaccinated for Hepatitis A Subject is allergic to aluminum, formaldehyde, sodium borate, latex, or any component of the vaccine Subject has received inactivated vaccines within 14 days of screening or live vaccines within 30 days of screening

Ages Eligible for Study
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Minimum Age: 12 Months
Maximum Age: 23 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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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>VAQTA™ | Biological: Hepatitis A Vaccine, Purified Inactivated (VAQTA™)<br>* Subjects will be given a 25-U/0.5 mL intramuscular injections of VAQTA™ at Day 1 and Month 6.<br>* Other names: VAQTA™;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hepatitis A Virus (HAV) Seroconversion Rate, i.e. the Percentage of Subjects Who Were Seronegative at Baseline and Developed Seropositive at Month 7 After Administration of a 2-dose Regime of Vaccines. | Seroconversion rate = (number of subjects with seronegative at baseline and developed seropositive at Month 7)/(number of subjects with seronegative at baseline regardless HAV serum status at Month 7). Measure serum HAV (hepatitis A virus) antibody at Day 0 prior to vaccination and at Month 7 after administration of a 2-dose regimen of vaccines. HAV antibody titers were determined by Wantai ELISA kit for serum antibody response to HAV. Seropositive was defined as HAV antibody titer ≥ 50 mIU/mL. Seronegative was defined as HAV antibody titer < 50 mIU/mL. | Collect blood sample for HAV antibody testing at Day 0 prior to vaccination, and Month 7 (4 weeks after administration of a 2-dose regimen of vaccines at Month 6) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serious Adverse Experiences and Systemic Adverse Experiences Occurring Within 14 Days After Each Vaccination, and Injection-site Complaints Occurring Day 1 Through Day 5 After Each Vaccination | All adverse experiences were collected from the time the consent form was signed through 14 days following the first vaccination(s) and from the time of the second vaccination through 14 days thereafter. The parent/legal guardian of each participant were requested to record injection-site adverse experiences and monitor the subject's temperature daily on the Vaccination Report Card for Day 1 thereafter for 4 additional calendar days, and record all systemic adverse experiences that occur during the 14-day period after each injection. | For serious adverse experiences and systemic adverse experiences: 14 days follow-up after each dose of vaccination; For injection-site adverse experiences: 5 days follow-up after each dose of vaccination |