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CompletedNCT01361776Updated Nov 18, 2015

Humoral Response to Tick-borne Encephalitis Vaccine in Elderly

A Phase 2/3 interventional study of FSME-immune in Tick-borne Encephalitis, sponsored by Sormland County Council, Sweden. Completed at 6 sites in 2 countries. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2015-11-18.

Sponsored by Sormland County Council, Sweden · Phase 2/3, Interventional, and Prevention

Phase
Phase 2/3
Study type
Interventional
Enrollment
200
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

Antibody titers after tick-borne encephalitis (TBE) vaccination are less in elderly and vaccination breakthroughs are more common in this age group. This has prompted Swedish authorities to recommend an additional dose in the initial vaccination schedule (= 0+30+90 days instead of the usually recommended 0+30 days. The investigators intend to evaluate this regime.

Read the detailed description

The risk for TBE increases in Sweden. Together with an increased awareness of the possibility to acquire protection by vaccination, this has led to an increase in the number of doses of the vaccine distributed in Sweden each year -now being approximately 400.000. The first year, two doses with an interval of 1 month is recommended for the general population, followed by a third dose approximately one year later and an additional booster dose three years after the third.

Recent studies show that the antibody titers against TBE are substantially less in an older population. This is in line with the present recommendation from Austria that booster intervals should be shortened to 3 years in the age group 60+. It is also in line with a report of vaccination failures where 13/27 patients were older than 60 years According to a study by Jilkowa et al, 18 % (38/185) in the age group 60+ did not achieve putative levels of antibody titers after the first two doses. Therefore, the manufacturer of Encepur recommends a total of three doses to this age group using the same regimen as with "accelerated vaccination schedule (0+7+21 days). Unfortunately, GMT (geometrical mean of titers) after 3 doses with the accelerated schedule are not superior to 2 doses given at 0+30 days.

The manufacturer of FSME-immun instead recommends that serology should be checked one month after the second dose and that a third dose should be given if titers are not sufficient (0+30+60 days). Unfortunately, determinations of titers in a large number of samples put severe strain on logistics and is not feasible in Sweden.

In order to try to improve immunity in the age group 60+ , the Department of Communicable Disease Control and Prevention in Stockholm therefore recommends a third dose two months after the first two doses to the age group 60+ (0+30+60 days).

Study design. The investigators intend to give FSME-immune to 3 groups with varying vaccination schedules ( 0+7+21, 0+30 or 0+30+90. 50 participants will be randomized to each group. Half of them will be between 50-59 years and half will be at least 60 years old. A younger age group (50 participants between 18-49 years) will serve as controls and will be given FSME-immune according to standard recommendations (0+30 days).

Serum samples (10 ml of blood) will be obtained at five times: 0,60,120,360 and 400 days after first dose Samples will be analysed for neutralising antibodies at the Swedish institute for Infectious disease control - other options possible.

02

Conditions studied

  • Tick-borne Encephalitis

Keywords

  • immune response
  • TBE-vaccine
  • elderly
  • additional doses
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 enrollment of 200 is close to the median of 192 across 32 interventional studies indexed under Encephalitis, Tick-Borne.

Browse Encephalitis, Tick-Borne studies →

Lead sponsor

Sormland County Council, Sweden is the lead sponsor of 11 studies on the registry; 2 are open to participants now.

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

04

Who can participate

Ages eligible
18 Years and older
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

  • Age 50 years or more
  • generally healthy
  • no condition
  • fertile women must use

Exclusion criteria

Exclusion Criteria:

  • Previous TBE infection
  • Previously immunized with TBE vaccine
  • Anaphylactic reaction to egg protein
  • Any disease or therapy which might suppress the immune response
  • Vaccination should be delayed if a participant has fever
Terms in these criteria, in plain language(2)

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.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

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 2 / Phase 3
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
200 participants (actual)

Study arms

  • Active comparator
    TBE vaccine at 0+30 days

    This group of 50 participants will follow the standard recommendation and will be given TBE vaccine 0.5 ml FSME immune at 0 + 30 days during the first year and an additional dose one year later

    Biological: FSME-immune

  • Active comparator
    TBE vaccine at 0+7+21 days

    This group of 50 participants will will be given TBE vaccine 0.5 ml FSME immune at 0 + 7 +21 days during the first year and an additional dose one year later

    Biological: FSME-immune

  • Active comparator
    TBE vaccinte at 0+30+90 days

    This group of 50 participants will will be given TBE vaccine 0.5 ml FSME immune at 0 + 30 + 90 days during the first year and an additional dose one year later

    Biological: FSME-immune

  • Active comparator
    younger participants

    This group of 50 participants in the age group 18-49 years will be given TBE vaccine 0.5 ml FSME immune at 0 +30 days during the first year and an additional dose one year later

    Biological: FSME-immune

Interventions

  • BiologicalFSME-immune

    0.5 ml im as scheduled in the 4 arms

06

What researchers measure

Primary outcomes

  1. Serum concentration of neutralising antibodies against TBE one month after two or three doses.

    Determination of neutralising antibodies one month after completion of the first years vaccination series

    Time frame: 18 months after the first dose

Secondary outcomes

  1. Serum concentration of neutralising antibodies against TBE one month after the dose which will be given a year later

    Determination of neutralising antibodies one month after the dose which will be given a year later

    Time frame: 18 months after the first dose has been given

07

Study locations

6 sites
  • Dept infectious diseases
    Helsingfors, 00029, Finland
  • Dept infectious diseases
    Eskilstuna, 631 88, Sweden
  • Dept infectious diseases
    Karlstad, 651 85, Sweden
  • Department of infectious diseases
    Stockholm, 17176, Sweden
  • Dept infectious diseases
    Uppsala, 751 85, Sweden
  • Department of infectious diseases
    Örebro, Sweden
08

References and documents

Publications

  • Kantele A, Rombo L, Vene S, Kundi M, Lindquist L, Erra EO. Three-dose versus four-dose primary schedules for tick-borne encephalitis (TBE) vaccine FSME-immun for those aged 50 years or older: A single-centre, open-label, randomized controlled trial. Vaccine. 2022 Feb 23;40(9):1299-1305. doi: 10.1016/j.vaccine.2022.01.022. Epub 2022 Jan 31. PubMed 35101266 ↗
09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Nov 18, 2015, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT01361776
Lead sponsor
Sormland County Council, Sweden
Responsible party
Lars Rombo (professor, Sormland County Council, Sweden) — Principal investigator
First posted
May 27, 2011
Start date
Sep 2011
Primary completion
Dec 2013
Completion
Jun 2014
Last update
Nov 18, 2015

Study contacts

lars rombo, MD
principal investigator · Karolinska Institutet

Oversight

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

Not currently enrolling

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

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