long-term B-cell immunity against tick-borne encephalitis (TBE) in healthy volunteers who have received 3-dose primary vaccination at an age between 18 and 31 years or older than 60 years.
Conditions
Interventions
Trade Name: FSME-IMMUN 0.5 ml
Product Name: FSME-IMMUN, 0.5 ml
Pharmaceutical Form: Suspension for injection
INN or Proposed INN: Inaktivierter Frühsommer-Meningoenzephalitis (FSME) Impfstoff
Other de
Sponsors
Department für Virologie, Medizinische Universität Wien
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: Volunteers that have received 3-dose primary TBE vaccination in the primary study 3 years ago. TBE-vaccination criteria fulfilled. Participants of the primary study who have received 3-dose primary TBE vaccination but did not participate in the follow-up analysis will also be included. All participants have to understand and sign informed consent form (based on the judgement of the study physician) Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 20 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 21
Exclusion criteria
Exclusion criteria: Contraindication to TBE vaccination (according to SmPC 2007) Immunodeficiency, history of autoimmune disease or current intake of immunomodulating drugs (corticosteroids) Pregnancy
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Main Objective: To determine the effect of age on long-term immunity after primary vaccination, a prospective study in volunteer participants who have received primary vaccination against tick-borne encephalitis (TBE), will be performed. The study includes 2 age groups: 1) healthy young adults who have received primary vaccination against TBE at 18-31 years of age, and 2) healthy old adults who have received primary vaccination against TBE at an age older than 60 years. Long-term B-cell-immunity will be assessed by determining TBEV-specifc antibody and memory B cells 3 years after primary vaccination. All study participants will receive the first booster vaccination with the licensed inactivated TBE vaccine (FSME-IMMUN, Baxter). Efficacy of booster vaccination will be compared among the 2 age groups by quantitative measurements of serum TBEV-specific antibody and memory B cell responses 1 and 4 weeks and 9 months after booster vaccination.;Secondary Objective: "not applicable";Primary end point(s): Frequency of TBEV-specific memory B cells measured by limiting dilution analysis;Timepoint(s) of evaluation of this end point: 3 years after primary TBE vaccination and 1 and 4 weeks and 9 months after first booster vacination | — |
Secondary
| Measure | Time frame |
|---|---|
| Secondary end point(s): Serum TBEV-specific IgG concentration and neutralizing antibody titer;Timepoint(s) of evaluation of this end point: 3 years after primary TBE vaccination and 1 and 4 weeks and 9 months after first booster vacination | — |
Countries
Austria
Contacts
Public ContactClinical Trials information
Department of Virology, Medical University of Vienna
Outcome results
None listed