A Safety and Efficacy Study of Two Japanese Encephalitis Vaccines ChimeriVaxTM-JE and JE-VAX

Study Overview
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Brief Summary
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The purpose of this study is to determine non-inferiority in seroconversion and to compare the safety and tolerability between ChimeriVax™-JE and JE-VAX® to the respective homologous virus strain and several wild types strains after completion of vaccination course.

Official Title
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Randomized, Double-blind, Phase II Study of the Safety, Tolerability and Immunogenicity Following Administration of Live Attenuated JE Vaccine (ChimeriVax™ JE) Compared With Mouse Brain-derived Inactivated JE Vaccine (JE VAX®).

Conditions
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Japanese Encephalitis

Intervention / Treatment
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* Biological: ChimeriVax™-JE vaccine
* Biological: JE-VAX® vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Written informed consent obtained. Aged ≥18 to <49 years. In good general health. Available for the study duration, including all planned follow-up visits. Females must have negative pregnancy test and be using adequate form of contraception Exclusion Criteria: Clinically significant abnormalities on laboratory and vital sign assessments. Anaphylaxis or other serious adverse reactions Administration of another vaccine within 30 days of study treatment period. Physical examination indicating any significant medical condition. Intention to travel out of the area prior to the study visit on Day 56. Seropositive to Hepatitis C Virus (HCV) or Human Immunodeficiency Virus (HIV) or positive for Hepatitis B Surface Antigen. Pregnancy. Excessive alcohol consumption, drug abuse. Involvement in another clinical study within 60 days preceding the screening visit and during study treatment period.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 48 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: ChimeriVax™-JE<br>Subjects received 2 injections of placebo (normal saline), 1 each on Days 0 and 7, and 1 injection of ChimeriVax™-JE on Day 28. | Biological: ChimeriVax™-JE vaccine<br>* 0.5 mL, subcutaneously<br>* Other names: ChimeriVax™-JE;|
| Active Comparator: JE-VAX®<br>Subjects received 1 injection of JE-VAX® each on Days 0, 7, and 28. | Biological: JE-VAX® vaccine<br>* 1.0 mL, subcutaneously<br>* Other names: JE-VAX®;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants Who Seroconverted to the Respective Homologous JE Vaccine Strain Up to 28 Days After the First Active Vaccination With Either ChimeriVax™-JE or JE-VAX® Vaccine | Immunogenicity was determined by analyzing antibody response of subjects to the respective homologous JE vaccine strain using a serum dilution 50% plaque reduction neutralization test (PRNT50). Seroconversion was defined as a 4 fold increase in antibody titer of ≥ 1:10 at baseline, or an antibody titer of ≥ 1:10 for participants with a baseline antibody titer of < 1:10. | Day 0 (pre-vaccination) and up to Day 56 post-vaccination | 
| Mean Antibody Titers of the Respective Homologous JE Vaccine Strain After the First Active Vaccination With Either JE-Vax ® or ChimeriVax™-JE | Immunogenicity was determined by analyzing antibody response of subjects to the respective homologous JE vaccine strain using a serum dilution 50% plaque reduction neutralization test (PRNT50). | Day 0 up to Day 56 post-vaccination | 
| Number Participants That Were Seropositive to the Respective Homologous JE Vaccine Strain Before and Post-Vaccination With Either ChimeriVax™-JE or JE-VAX® Vaccine. | Immunogenicity was determined by analyzing antibody response of subjects to the respective homologous JE vaccine strain using a serum dilution 50% plaque reduction neutralization test (PRNT50). Seropositive status for the ChimeriVax™-JE group was based on the ChimeriVax™-JE virus strain and positive status for the JE-VAX® group was based on the Nakayama virus strain. Participants were defined as seropositive if they had an antibody titer of ≥ 1:10. [Seropositive status can be 'Yes' or 'No'] | Day 0 (Pre-vaccination) and up to Month 12 After First Dose | 
| Mean Antibody Titers to the Respective Homologous JE Vaccine Strain Post Vaccination With Either ChimeriVax™-JE or JE-VAX® | Immunogenicity was determined by analyzing antibody response of subjects to the respective homologous JE vaccine strain using a serum dilution 50% plaque reduction neutralization test (PRNT50). | Day 0 (pre-vaccination) up to month 12 post-vaccination | 
| Number of Participants Reporting at Least One Treatment Emergent Adverse Event Following Vaccination With Either ChimeriVax™ JE or JE-VAX® | Grade 3 (severe) adverse events were defined as incapacitating with inability to work or perform usual activity. | Day 0 up to Day 6 post-vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Japanese encephalitis, ChimeriVax™-JE, JE-VAX®