Immunogenicity, Safety and Interchangeability of Two Tbe Vaccines Administered According to a Conventional Schedule in Children

Study Overview
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Brief Summary
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The objective of this study is to assess the immunogenicity, safety and interchangeability of two different TBE vaccines in children aged 1-11 years, the first and second vaccination with either FSME-IMMUN 0.25ml Junior or Encepur 0.25ml Children and the third vaccination with FSME-IMMUN 0.25 ml Junior only, administered according to the conventional schedule (0, 28 and 360 days).

Official Title
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Single-blind, Randomized, Phase 3B Study in Children Aged 1 - 11 Years to Investigate the Immunogenicity, Safety and Interchangeability of Two Tick-borne Encephalitis (Tbe) Vaccines Administered According to a Conventional Schedule

Conditions
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Encephalitis, Tick-Borne

Intervention / Treatment
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* Biological: Tick-Borne Encephalitis (TBE) Vaccine (Inactivated)
* Biological: Tick-Borne Encephalitis (TBE) Vaccine (Inactivated)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and female children will be eligible for participation in this study if: they are aged >= 1 years (from the 1st birthday) to 11 years (to the last day before the 12th birthday) at screening; their parents / legal guardians provide written informed consent; children provide written assent to the study according to age and capacity of understanding; their parents/guardians understand the nature of the clinical study and will comply with the requirements of the protocol (e.g., completion of the Subject Diary, return for follow-up visits); they are generally healthy, (i.e. the physician would have no reservations vaccinating with a TBE vaccine outside the scope of a clinical study); provide a negative pregnancy test result at the first medical examination (if the subject is a female and capable of bearing children). Exclusion Criteria: Subjects will be excluded from participation if: they have a history of any previous TBE vaccination; they have a history of TBE infection; they have a history of infection with other flaviviruses; they have a history of vaccination against yellow fever and/or Japanese B encephalitis; they have a history of severe allergic reactions, in particular a known sensitivity or allergy to any components of the vaccines; they are suffering from a disease (e.g. autoimmune disease) or are undergoing a form of treatment (e.g. systemic corticosteroids) that can be expected to influence immunological functions; they have received any blood product or immunoglobulins within 90 days prior to study entry; they are known to be Human Immunodeficiency Virus (HIV) positive (an HIV test is not required specifically for the purpose of this study); they have a functional or surgical asplenia; they have a rash or other dermatological condition at the injection site which could interfere with injection site reaction evaluation; they were administered an investigational product within six weeks prior to study start or are concurrently participating in another clinical study that includes the administration of an investigational product; they are pregnant or breastfeeding (if a female subject); they or their parents/legal guardian(s) are in a dependent relationship with the study investigator or with a study team member. Dependent relationship includes close relatives (i.e., children or grandchildren, partner/spouse, siblings) as well as employees of the investigator or site conducting the study. Subjects who have an acute illness with or without elevated body temperature (>=37.5°C) within 3 days prior to the scheduled first vaccination will not be vaccinated. Subjects may be included at a repeat visit provided that (1) the illness has resolved (body temperature < 37.5 °C), (2) the repeat visit is no more than 14 calendar days after the Screening Visit, and (3) the center is still open for recruitment. If subjects have received antipyretics within 4 hours prior to the scheduled time of vaccination, the vaccination should be performed at a later date, as long as the center is still open for recruitment. Subjects who received any live vaccine within 4 weeks or any inactivated vaccine within 2 weeks prior to the scheduled first study vaccination will not be vaccinated until an interval of 4 or 2 weeks, respectively, has passed, provided the center is still open for recruitment. If a subject was bitten by a tick within 4 weeks prior to the scheduled first or second vaccination, the vaccination must be postponed until an interval of 4 weeks has passed.

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 11 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>Subjects receive three vaccinations with a paediatric TBE vaccine according to the conventional vaccination schedule. | Biological: Tick-Borne Encephalitis (TBE) Vaccine (Inactivated)<br>* Subjects receive three vaccinations with FSME-IMMUN 0.25ml Junior on days 0, 28 and 360<br>|
| Experimental: 2<br>Subjects receive three vaccinations with a paediatric TBE vaccine according to the conventional vaccination schedule. | Biological: Tick-Borne Encephalitis (TBE) Vaccine (Inactivated)<br>* Subjects receive two vaccinations with Encepur 0.25ml Children on days 0 and 28 and a third vaccination with FSME-IMMUN 0.25ml Junior on day 360.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seropositivity rate as determined by neutralization test (NT) 28 days after the second vaccination |  | 28 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seropositivity rate determined by NT 180 days after the first vaccination and 28 days after the third vaccination |  | 28, 180 days | 
| Seropositivity rate determined by ELISA 28 days after the second vaccination, 180 days after the first vaccination and 28 days after the third vaccination |  | 28, 180 days | 
| Antibody response measured by NT/ELISA 28 days after the second vaccination, 180 days after the first vaccination and 28 days after the third vaccination |  | 28, 180 days | 
| Fold increase of antibody response measured by NT/ELISA 28 days after the second vaccination, 180 days after the first vaccination and 28 days after the third vaccination as compared to baseline |  | 28, 180 days | 
| Frequency and severity of injection site reactions/systemic reactions occurring after each vaccination |  | 28 days | 
| Frequency and severity of adverse experiences (AEs) observed during the entire follow-up period |  | 388 days |