Clinical trial NCT01296360: Open-label, Randomized Study in a Pediatric Population in a JEV (Japanese Encephalitis Virus)-Endemic Country
Official title: Long-Term Immunity and Safety With or Without a Booster Dose Following Primary Vaccination With the Japanese Encephalitis Vaccine IC51 (IXIARO®) in a Pediatric Population in a JEV-Endemic Country. Open-Label, Randomized, Phase 3 Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: Japanese Encephalitis
Keywords: immune response
IC51-325
Japanese Encephalitis
Intercell AG
Lead sponsor: Valneva Austria GmbH
Sponsor class: INDUSTRY
First posted: 2011-02-15
Enrollment: 300
Sex: ALL
Minimum age (years): 9
Maximum age (years): 18
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: This is a randomized, open-label Phase 3 study including children aged \>9 months to \<17 years and 7 months who have been vaccinated with IXIARO in study IC51-323.

Detailed description: This is a randomized, open-label Phase 3 study including children aged \>9 months to \<17 years and 7 months who have been vaccinated with IXIARO in the previous study IC51-323.

Eligibility criteria: Inclusion Criteria:

* Children and adolescents who have completed study IC51-323 and received both IXIARO vaccinations according to protocol.
* Children who have received the dose confirmed for their age group.
* Male or female healthy children and adolescents aged ≥9 months to \<17 years and 7 months at the time of enrolment into this study.
* Written informed consent by the subject's legal representative(s), according to local requirements, and written informed assent of the subject, if applicable.
* Female subjects: either no childbearing potential or negative pregnancy test (pregnancy test to be performed in female subjects after onset of menarche) at Visits 1, 2 and 2a as stipulated by the protocol. For females after menarche willingness to practice a reliable method of contraception

Exclusion Criteria:

* Vaccination against JE virus (JEV) (except within study IC51-323 and IC51 325), Yellow fever, West Nile virus and Dengue fever at any time prior to or planned during the study.
* History of or clinical manifestation of any Flavivirus disease during IC51-323 or IC51 325.
* Participation in another study with an investigational drug during IC51 323 or IC51 325.
* Planned active or passive immunization within 2 weeks before and 1 week after the IXIARO booster.
* History of or development of any immunodeficiency including post-organ-transplantation after inclusion into IC51-323 or IC51 325.
* History of or development of an autoimmune disease during study IC51-323 or IC51 325.

  * Administration of chronic (defined as more than 14 days) immunosuppressants or other immune-modifying medications started during IC51-323 or IC51 325. (For corticosteroids, this would mean prednisone or equivalent at \>0.05 mg/kg/day; topical and inhaled steroids are allowed).
* Acute febrile infection at Visit 2 (only for the Booster Group).
* Pregnancy (positive pregnancy test at Visit 1 and Visit 2), lactation or unreliable contraception in female subjects after onset of menarche.
* Hypersensitivity reactions to IXIARO or adverse events in study IC51-323 requiring withdrawal from further vaccination or anaphylaxis or severe cases of atopy requiring emergency treatment or hospital admission during IC51-323 or IC51 325.
* History of urticaria after hymenoptera envenomation, drugs, physical or other provocations or of idiopathic cause during IC51-323 or IC51 325.
* Known infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV) (measurement of Hepatitis B surface antigen \[HBsAg\] titers) or hepatitis C virus (HCV).
* Illicit drug use and/or current drug or alcohol addiction.
* Inability or unwillingness by the legal representative(s) and/or the subject (where applicable) to provide informed consent/assent and to abide by the requirements of the study.
* Persons who have been committed to an institution (by a court or by an authority).

Primary outcomes:
measure: SCRs (Seroconversion Rate) as Defined by Percentage of Subjects With Plaque Reduction Neutralization Test Titers of>1:10 at 1 Month After the Booster Dose
timeFrame: 1 month post booster
Secondary outcomes:
measure: Rate of Subjects Achieving a >4-fold Increase in JEV (Japanese Encephalitis Virus) Neutralizing Antibody Titers at 1 Month After the Booster Dose
timeFrame: 1 month
measure: GMTs (Geometric Mean Titre) for JEV Neutralizing Antibodies Measured Using a Validated PRNT (Plaque Reduction Neutralization Test) at 1 Month After the Booster Dose
timeFrame: 1 month
measure: GMTs and Rate of Subjects With a PRNT Titer of >1:10 at Months 12, 24 and 36 After First IXIARO Vaccination in IC51-323 With and Without Booster Vaccination
timeFrame: 36 months
measure: Rate of Subjects With SAEs (Serious Adverse Events) Following Immunization and Medically Attended AEs (Adverse Events) up to Months 12, 24 and 36 After the First IXIARO Vaccination in IC51 323 With and Without Booster Vaccination. Severity, Duration and
timeFrame: 36 months
measure: Rate of Subjects With Unsolicited AEs (Adverse Events) up to Months 12, 24 and 36 After the First IXIARO Vaccination in IC51 323 With and Without Booster Vaccination. Severity, Duration and Relationship to Vaccinations.
timeFrame: 36 months
measure: Rate of Subjects With SAEs and Medically Attended AEs Within 1 Month Following the Booster Dose. Severity, Duration and Relationship to Vaccinations.
timeFrame: 1 month
measure: Rate of Subjects With Unsolicited AEs Within 1 Month Following the Booster Dose. Severity, Duration and Relationship to Vaccinations.
timeFrame: 1 month
measure: Rate of Subjects With Solicited AEs for up to 7 Days Following the Booster Dose. Severity and Duration.
timeFrame: 7 days
Other outcomes:
Locations:
city: Muntinlupa City
country: Philippines
facility: Research Institute for Tropical Medicine - Clinical Research Division
state: Alabang
city: Muntinlupa City
country: Philippines
facility: Research Institute for Tropical Medicine
state: Alabang
city: Manila
country: Philippines
facility: UP-Philippine General Hospital
Study officials:
affiliation: Valneva Austria GmbH
name: Vera Kadlecek, Mag.
role: STUDY_CHAIR
References: