ClinicalTrials.gg
CompletedNCT00161967Updated May 21, 2015

TBE Antibody Persistence and Booster Vaccination Study in Children and Adolescents (Follow-up to Study 209)

A Phase 4 interventional study of Tick-Borne Encephalitis (TBE) Vaccine (Inactivated) in Encephalitis, Tick-Borne, sponsored by Pfizer. Completed at 3 sites in 3 countries. Open to participants aged 3 Years to 18 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2015-05-21.

Sponsored by Pfizer · Phase 4, Interventional, and Prevention

Phase
Phase 4
Study type
Interventional
Enrollment
375
Allocation
Non-randomized
Ages
3 Years to 18 Years
Sex
All
01

Study summary

The purpose of this study is to assess the seropersistence of TBE antibodies in children and adolescents aged 1 to 15 years at the time of their first vaccination, 24 months and 34 months after completion of primary immunization with FSME-IMMUN 0.25 ml (3 vaccinations during the predecessor study 209), as well as the immune response to a booster vaccination with FSME-IMMUN 0.25 ml or FSME-IMMUN 0.5 ml administered 36 months after the third vaccination (in Study 209).

Protocol amendment of October 2006: The study has been prolonged for children and adolescents who still showed highly positive TBE virus antibody concentrations at approximately 3 years after the third vaccination and therefore did not receive a booster vaccination at this time point. Further follow-up of TBE antibody persistence is now included for these subjects at 46 and 58 months after the third vaccination (in Study 209), as well as a booster vaccination offered at either 48 or 60 months after the third vaccination (in Study 209), depending on individual TBE antibody levels.

02

Conditions studied

  • Encephalitis, Tick-Borne

Keywords

  • tick-borne encephalitis
03

In context

Encephalitis, Tick-Borne

51 studies on the registry are indexed under Encephalitis, Tick-Borne; 9 are open to participants now.

This study's planned enrollment of 375 is above the median of 192 across 32 interventional studies indexed under Encephalitis, Tick-Borne.

Browse Encephalitis, Tick-Borne studies →

Lead sponsor

Pfizer is the lead sponsor of 3,334 studies on the registry; 149 are open to participants now.

Of its 601 completed or terminated interventional studies of FDA-regulated products, 391 (65%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
3 Years to 18 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Participated in Baxter study 209 and:
  • They and/or their parents / legal guardians understand the nature of the study and agree to its provisions
  • Written is available from the parents / legal guardians according to national law
  • Written informed assent is available from the child/adolescent according to age and capacity of understanding
  • They received the third vaccination with FSME-IMMUN 0.25 ml during the course of Baxter study 209
  • Blood was drawn after their third vaccination during the course of Baxter study 209
  • They showed an ELISA concentration > 126 VIE U/ml and / or a NT titer >=10 after the third vaccination in Baxter study 209
  • They or their parents / legal guardians agree to keep a Subject Diary

Exclusion criteria

Exclusion Criteria:

  • Received any TBE vaccination since their third vaccination with FSME-IMMUN 0.25 ml
  • Have a history of infection with or vaccination against other flaviviruses (Dengue fever, yellow fever and / or Japanese B-encephalitis virus) since their third vaccination with FSME-IMMUN 0.25 ml
  • Are known to be positive (a special HIV test is not required for the purpose of the study) since their third vaccination with FSME-IMMUN 0.25 ml
  • Received a blood transfusion or immunoglobulins within 30 days of the first and second blood draw (as applicable)
  • Have a known or suspected problem with drug or alcohol abuse (> 4 liters wine / week or equivalent level of other alcoholic beverages)
  • Have participated in another Baxter vaccine study within the last six months (with the exception of follow-up studies)

Subjects will not be eligible for booster vaccination if they:

  • Do not meet the inclusion / exclusion criteria
  • Are not clinically healthy, (i.e. the physician would have reservations vaccinating with a TBE vaccine outside the scope of a clinical trial)
  • Suffer from a disease (e.g. disease) or are undergoing a form of treatment (e.g. systemic ) that can be expected to influence immunological functions
  • Have shown an allergic reaction to one of the components of the vaccine since their third vaccination in Baxter study 209
  • Have donated blood or plasma within 30 days of the booster vaccination if female of - are pregnant or breastfeeding before the booster vaccination (positive pregnancy test result at the medical examination before the booster vaccination)
  • Are simultaneously participating in another clinical trial including administration of an product within six weeks prior to the booster vaccination until the end of the study

Subjects who meet the inclusion/exclusion criteria, but have a febrile illness (body temperature >=38.0°C, measured orally) at the scheduled time of vaccination will not be vaccinated until their body temperature returns to normal.

Subjects who received any vaccination within 4 weeks prior to the booster vaccination will not be vaccinated until an interval of four weeks has passed.

If subjects received antipyretics within 4 hours prior to the intended TBE vaccination, the vaccination should be performed at a later time.

Females of childbearing potential will only be vaccinated if they agree to employ adequate measures from 4 weeks before the booster vaccination until the end of the study.

Terms in these criteria, in plain language(7)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Autoimmune disease

A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.

Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

05

Study design

Phase
Phase 4
Primary purpose
Prevention
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
375 participants (estimated)

Interventions

06

What researchers measure

Primary outcomes

  1. Seropositivity rate measured by ELISA and/or NT according to Adner et al., 2001 at each available time point after the third vaccination in study 209 and separately at each available time point after the booster vaccination in this study

    Time frame: TBE virus antibody tests at pre-determined intervals with the last test at 21-35 days after the booster vaccination in this study

07

Study locations

3 sites
  • Grieskirchner Strasse 17
    Wels, Upper Austria 4600, Austria
  • Hauptstrasse 240
    Kehl, 77694, Germany
  • Niepubliczny ZOZ
    Zamosc, 22-400, Poland
08

Timeline

Tracking since Sep 25, 2026
Not marked actual or estimatedDates not marked actual or estimated

The record gives a start of May 2005, a primary completion of Jul 2008 and a completion of Nov 2008. It does not say whether these dates are actual or estimated.

How these figures are worked out, and which studies are left out of them.

Registered
Sep 8, 2005
First posted
Sep 13, 2005
Start
May 2005
Primary completionActual
Jul 2008
CompletionActual
Nov 2008
Last update
May 21, 2015
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on May 21, 2015, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT00161967
Lead sponsor
Pfizer
First posted
Sep 13, 2005
Start date
May 2005
Primary completion
Jul 2008
Completion
Nov 2008
Last update
May 21, 2015

Study contacts

Baxter BioScience Investigator
principal investigator · Baxter BioScience

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in May 2015. You cannot join it, but the record below documents what was studied.

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Studies of the drug tested here: Tick-borne encephalitis vaccine

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