Study of Japanese Encephalitis Chimeric Virus Vaccine (JE-CV) in Children Previously Immunized With JE-CV
Condition: Japanese Encephalitis; Varicella
MeSH terms: Chickenpox; Herpes Zoster; Encephalitis, Japanese; Encephalitis
Intervention: JE-CV Vaccine; Varicella Vaccine
Intervention description: 0.5 mL (single dose), Subcutaneous; 0.5 mL (single dose), Subcutaneous
Intervention MeSH terms: Vaccines
Phase: Phase 3
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: This was an open, controlled, multicenter, Phase III trial. Participants in Group 1 were previously vaccinated at 12 to 18 months of age with a single dose of JE-CV vaccine and were to receive a booster dose of JE-CV vaccine on Day 0. This group was not randomized. JE vaccine naïve control children were randomized to receive one single dose of JE-CV on Day 0 (Group 2) or a varicella vaccination on Day 0 (Group 3).
Masking: None (Open Label)
Enrollment: 454.0
Sex: All
Minimum age: 36 Months
Maximum age: 42 Months
Healthy volunteers: Accepts Healthy Volunteers
Keywords: Japanese Encephalitis; Japanese encephalitis chimeric virus vaccine; Varicella; Varicella vaccine

Summary:

      The aim of the study is to investigate the memory immune response and the yearly persistence
      of the immunity against Japanese Encephalitis (JE) after vaccination with Japanese
      Encephalitis Chimeric Virus Vaccine (JE-CV) in participants previously vaccinated with JE-CV
      vaccine.

      Objectives:

        -  To describe JE immune status before and after JE-CV vaccination in subjects previously
           vaccinated with JE-CV vaccine

        -  To describe the immune status before and after JE-CV vaccination in JE-naïve control
           subjects.

        -  To describe the safety (in terms of solicited and unsolicited adverse events) of a
           single dose of JE-CV vaccine up to 6 months after the last vaccination.

        -  To describe all related serious adverse events (SAEs) and related deaths from 6 months
           to 5 years after vaccination in JE-CV-primed subjects.
    

Eligibility criteria:

        An individual had to fulfill all of the following criteria in order to be eligible for
        trial enrollment:

        All Participants

          -  Aged 36 to 42 months on the day of inclusion

          -  Provision of Informed Consent Form signed by at least one parent or other legally
             acceptable representative

          -  Participant and parent/legally acceptable representative or guardian able to attend
             all scheduled visits and to comply with all trial procedures

          -  In good general health, based on medical history and physical examination

        For JE-CV vaccine primed group only

          -  Participant who was vaccinated with JE-CV in JEC02 trial (NCT00735644)

        An individual fulfilling any of the following criteria was excluded from trial enrollment:

        All Participants

          -  Participation in another clinical trial investigating a vaccine, drug, medical device,
             or medical procedure in the 4 weeks preceding the trial vaccination

          -  Planned participation in another clinical trial during the Day 0 - Month 6 period and
             for Group 1 up to 5 years for any flavivirus vaccine trial

          -  Receipt of any vaccine* in the 4 weeks preceding the trial vaccination, except for
             pandemic influenza vaccination, which may be received at least 2 weeks before study
             vaccines

          -  Planned receipt of any vaccine* in the 4 weeks following the trial vaccination, except
             for pandemic influenza vaccine. In the event of local or national immunization program
             with a pandemic influenza vaccine, participants who receive a pandemic influenza
             vaccine at any time during the trial will not be withdrawn from the trial.

          -  Planned receipt of any JE vaccine during the course of the trial

          -  Administration of any anti-viral within 2 months preceding the trial vaccination and
             up to 4 weeks following the trial vaccination

          -  Receipt of blood or blood-derived products in the past 3 months, which might interfere
             with assessment of the immune response

          -  Known or suspected congenital or acquired immunodeficiency; or receipt of
             immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy within
             the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or
             equivalent for more than 2 consecutive weeks within the past 3 months)

          -  Seropositivity for human immunodeficiency virus (HIV), hepatitis B, or hepatitis C, as
             reported by the parent/legally acceptable representative

          -  History of central nervous system disorder or disease, including seizures and febrile
             seizures

          -  Known systemic hypersensitivity to any of the vaccine components, or history of a
             life-threatening reaction to the vaccine used in the trial or to a vaccine containing
             any of the same substances

          -  Chronic illness or any underlying illness (such as cardiovascular, kidney, liver or
             hematological disease or development abnormalities) that, in the opinion of the
             investigator, is at a stage where it might interfere with trial conduct or completion

               -  Except in case of national immunization days with oral polio vaccine

        For JE-CV primed participants only

          -  Receipt of any JE vaccine other than JE-CV during JEC02 trial(NCT00735644) and since
             the end of JEC02 trial

        For JE-CV naïve participants only

          -  Previous vaccination against flavivirus disease including JE

          -  History of flavivirus infection either based on clinical suspicion or laboratory
             proven

          -  Previous vaccination against varicella

          -  Previous vaccination with JE-CV in JEC02 study

          -  History of varicella, confirmed either clinically, serologically, or microbiologically

          -  Known systemic hypersensitivity or anaphylactic/anaphylactoid reaction to neomycin.

          -  Known history of thrombocytopenia or idiopathic thrombocytopenic purpura

        Temporary Contraindications:

        A prospective participant was not to be included in the study until the following
        conditions and/or symptoms had resolved:

          1. Receipt of oral or injected antibiotic therapy within 72 hours prior to the first
             blood draw (for Groups 1 and 2)

          2. Febrile illness (temperature ≥38.0°C [≥100.4°F]) or moderate or severe acute
             illness/infection (according to investigator judgment) on the day of vaccination (for
             all participants)

        The Investigator was to postpone vaccination until the situation/condition resolved.
        Vaccination could be postponed within the timeframe for vaccination indicated in the
        protocol trial flowchart.