TBE Seropersistence up to 10 Years After First Booster in Adults

Phase 4

Completed

• Conditions: Tick-borne Encephalitis (TBE)
• Interventions: Biological: FSME-IMMUN 0.5 ml

• Registration Number: NCT01582698
• Lead Sponsor: Pfizer

Brief Summary

The purpose of this study is to evaluate TBE antibody persistence from 7 to 10 years after the first booster TBE vaccination with FSME-IMMUN 0.5ml.

Detailed Description

Not available

Study Timeline

• Study Start: 2012-04
• Study First Submitted: 2012-04-20
• Study First Submitted QC: 2012-04-20
• Study First Posted: 2012-04-23
• Primary Completion: 2015-06
• Study Completion: 2015-06
• Status Verified: 2021-01
• Last Update Submitted: 2021-01-20
• Last Update Posted: 2021-01-22

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 243

Inclusion Criteria

Subjects who participated in the first and second precursor studies will be eligible for participation in this study if:

• they understand the nature of the study, agree to its provisions and provide written informed consent
• they received the first booster vaccination with FSME-IMMUN 0.5ml during the first precursor study and did not receive a second booster vaccination in the second precursor study
• blood was drawn after their first booster vaccination in the first precursor study

Exclusion Criteria

Subjects will be excluded from participation in this study if they:

• received any TBE vaccination since their first booster vaccination with FSME-IMMUN 0.5ml
• have a history of infection with or vaccination against other flaviviruses (e.g. dengue fever, yellow fever, Japanese B-encephalitis) since their first booster vaccination with FSME-IMMUN 0.5ml
• are known to be HIV positive since their first booster vaccination with FSME-IMMUN 0.5ml
• have a known or suspected problem with drug or alcohol abuse

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Seropersistence evaluation + 2nd booster vaccination	FSME-IMMUN 0.5 ml	Blood will be drawn to assess the seropersistence of TBE virus antibodies at 82, 94, 106 and 118 months after the first booster vaccination with FSME-IMMUN 0.5ml administered during the first precursor study. Timing of the second booster vaccination will depend on the level of serum TBE antibodies observed during the study. Blood will be drawn 21 - 35 days after vaccination to assess the booster response.

Primary Outcome Measures

Name	Time	Method
Seropositivity rate measured by neutralization test (NT) 82, 94, 106 and 118 months after the first booster TBE vaccination administered in the first precursor study and after the booster vaccination in this study	118 months

Secondary Outcome Measures

Name	Time	Method
Seropositivity rate measured by ELISA test 82, 94, 106 and 118 months after the first booster TBE vaccination administered in the first precursor study and after the booster vaccination in this study	118 months
Fold increase in antibody concentration after the booster vaccination administered as compared to before the booster vaccination in this study measured by ELISA and by NT	118 months
Antibody titers 82, 94, 106 and 118 months after the first booster TBE vaccination administered in the first precursor study and after the booster vaccination in this study measured by ELISA and by NT	118 months

Trial Locations

Locations (2)

Prywatny Gabinet Lekarski; 🇵🇱 Dębica, Poland

"John Paul II" Cracow Specialist Hospital, Department of Pediatric Neuroinfections and Neurology; 🇵🇱 Krakow, Poland