NCT00595270

Brief Summary

The study investigates the long term persistence the Japanese encephalitis vaccine IC51 and the need of a booster dose

Trial Health

100
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
349

participants targeted

Target at P50-P75 for phase_3

Timeline
Completed

Started Oct 2005

Typical duration for phase_3

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

October 1, 2005

Completed
1.9 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 1, 2007

Completed
4 months until next milestone

First Submitted

Initial submission to the registry

January 4, 2008

Completed
12 days until next milestone

First Posted

Study publicly available on registry

January 16, 2008

Completed
1.2 years until next milestone

Study Completion

Last participant's last visit for all outcomes

April 1, 2009

Completed
4.9 years until next milestone

Results Posted

Study results publicly available

March 7, 2014

Completed
Last Updated

March 7, 2014

Status Verified

February 1, 2014

Enrollment Period

1.9 years

First QC Date

January 4, 2008

Results QC Date

December 5, 2013

Last Update Submit

February 5, 2014

Conditions

Japanese Encephalitis

Outcome Measures

Primary Outcomes (1)

  • Long Term Immunogenicity of IC51 Vaccine 24 Months After the Primary Vaccination

    Seroprotection rate (SPR) (anti-JEV neutralizing antibody titer ≥ 1:10) 24 months (M24) after the primary vaccination - imputed; Persistence of immunogenicity (SPR) at M24 defined as: * pos. (positive) (persistent): Subjects * with a non-missing, pos. seroconversion at D56 (Study IC51-304) and * without booster at M11 or M23 and * with non-missing, seroprotection (SP) pos. PRNT50 at M6 or M12 and * with non-missing, SP pos. PRNT50 at M24 * neg. (negative) (non-persistent): Subjects with * missing or neg. seroconversion at D56 (Study IC51-304) or * booster at M11 or at M23, or * non-missing, SP neg. PRNT50 at M6 or M12 or * missing PRNT50 at both M6 and M12 or * missing or SP neg. PRNT50 (serum dilution giving 50% reduction in plaques in a Plaque Reduction Neutralization Test) at M24

    - 24 months

Secondary Outcomes (6)

  • SPR 24 Months After the Primary Vaccination (Observed)

    24 months

  • Persistent and Actual SPR 6, 12 and 24 Months After Primary Vaccination

    - 24 months

  • Persistent and Actual GMT 6, 12 and 24 Months After Primary Vaccination

    24 months

  • SCR 1 Month After the Booster Doses

    1 month

  • GMT 1month After Booster Doses

    1 month

  • +1 more secondary outcomes

Study Arms (1)

IC51

OTHER

In study IC51-305, subjects who had received IC51 in study IC51-304 were tested for seroconversion 6 months after the first vaccination. Subjects who had protective titers were again tested for persistence of immunity at 12 months after the first immunization,whereas subjects who had titers below the seroconversion threshold by Month 6 received a booster dose of 1x6 mcg IC51 at Month 11. Their immune response was also assessed at Month 12. Thereafter, subjects who had no protective titer by Month 12 received a booster dose of 1x6 mcg IC51 at Month 23, regardless of prior treatment; and neutralizing antibody titers were reassessed at Month 24. Subjects who had protective titers at month 12 did not receive a booster at Month 23, and their neutralizing antibody titer was also assessed at Month 24.

Biological: IC51

Interventions

IC51BIOLOGICAL
Also known as: Japanese Encephalitis purified inactivated vaccine
IC51

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • At least 18 years of age
  • Written informed consent obtained prior to study entry
  • Subjects correctly included in and having completed study IC51-304 according to the protocol.

You may not qualify if:

  • Use of any other investigational or non-registered drug or vaccine in addition to the study vaccine during the study period
  • Immunodeficiency including post-organ-transplantation or immunosuppressive therapy
  • Pregnancy, lactation or unreliable contraception in female subjects

Contact the study team to confirm eligibility.

Sponsors & Collaborators

MeSH Terms

Conditions

Encephalitis, Japanese

Condition Hierarchy (Ancestors)

Encephalitis, ArbovirusEncephalitis, ViralCentral Nervous System Viral DiseasesCentral Nervous System InfectionsInfectionsInfectious EncephalitisArbovirus InfectionsVector Borne DiseasesMosquito-Borne DiseasesVirus DiseasesRNA Virus InfectionsFlavivirus InfectionsFlaviviridae InfectionsEncephalitisBrain DiseasesCentral Nervous System DiseasesNervous System DiseasesNeuroinflammatory Diseases

Results Point of Contact

Title
Senior Manager Clinical Research
Organization
Intercell AG
kdubischar.kastner@intercell.com
+43 1 206 20

Study Officials

  • Susanne Eder

    Valneva Austria GmbH

    STUDY DIRECTOR

Publication Agreements

PI is Sponsor Employee
No
Restriction Type
OTHER
Restrictive Agreement
Yes

Study Design

Study Type
interventional
Phase
phase 3
Allocation
NA
Masking
NONE
Purpose
PREVENTION
Intervention Model
SINGLE GROUP
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

January 4, 2008

First Posted

January 16, 2008

Study Start

October 1, 2005

Primary Completion

September 1, 2007

Study Completion

April 1, 2009

Last Updated

March 7, 2014

Results First Posted

March 7, 2014

Record last verified: 2014-02