Back to resultsLong Term Persistence and Effect of a Booster Dose of the Japanese Encephalitis Vaccine IC51
Primary Purpose
Japanese Encephalitis
Status
Completed
Phase
Phase 3
Locations
Study Type
Interventional
Intervention
IC51
Sponsored by
About this trial
This is an interventional prevention trial for Japanese Encephalitis
Eligibility Criteria
Inclusion Criteria:
- 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.
Exclusion Criteria:
- 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
Sites / Locations
Arms of the Study
Arm 1
Arm Type
Other
Arm Label
IC51
Arm Description
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.
Outcomes
Primary Outcome Measures
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
Secondary Outcome Measures
SPR 24 Months After the Primary Vaccination (Observed)
Persistence of immunogenicity (SPR) at M24 (observed) defined as :
positive (persistent): Subjects
with a non-missing, positive seroconversion at D56 (Study IC51-304), and
who did not receive a booster dose at Visit 2 (M11) or Visit 4 (M23), and
with a non-missing, SP positive PRNT50 result at Visit 1 (M6) or Visit 3 (M12), and
with a non-missing, SP positive PRNT50 result at Visit 5 (M24)
negative (non-persistent): Subjects
with missing or negative seroconversion at D56 (Study IC51-304), or
who did receive a booster dose at Visit 2 (M11) or at Visit 4 (M23), or
with a non-missing, SP negative PRNT50 result at Visit 1 (M6) or Visit 3 (M12), or
with a missing PRNT50 result at both Visit 1 (M6) and Visit 3 (M12), or
with a non-missing, SP negative PRNT50 result at Visit 5 (M24)
Persistent and Actual SPR 6, 12 and 24 Months After Primary Vaccination
Persistent and Actual GMT 6, 12 and 24 Months After Primary Vaccination
SCR 1 Month After the Booster Doses
GMT 1month After Booster Doses
Safety Profile of IC51
Full Information
1. Study Identification
Unique Protocol Identification Number
NCT00595270
Brief Title
Long Term Persistence and Effect of a Booster Dose of the Japanese Encephalitis Vaccine IC51
Official Title
Long Term Persistence and Effect of a Booster Dose of the Japanese Encephalitis Vaccine IC51
Study Type
Interventional
2. Study Status
Record Verification Date
February 2014
Overall Recruitment Status
Completed
Study Start Date
October 2005 (undefined)
Primary Completion Date
September 2007 (Actual)
Study Completion Date
April 2009 (Actual)
3. Sponsor/Collaborators
Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Valneva Austria GmbH
4. Oversight
Data Monitoring Committee
No
5. Study Description
Brief Summary
The study investigates the long term persistence the Japanese encephalitis vaccine IC51 and the need of a booster dose
Detailed Description
This is an open label, non-randomized multi-center phase 3 follow-up study. All volunteers having completed trial IC51-304 (NCT00595790) will be enrolled into this trial at 2 sites
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Japanese Encephalitis
7. Study Design
Primary Purpose
Prevention
Study Phase
Phase 3
Interventional Study Model
Single Group Assignment
Masking
None (Open Label)
Allocation
N/A
Enrollment
349 (Actual)
8. Arms, Groups, and Interventions
Arm Title
IC51
Arm Type
Other
Arm Description
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.
Intervention Type
Biological
Intervention Name(s)
IC51
Other Intervention Name(s)
Japanese Encephalitis purified inactivated vaccine
Primary Outcome Measure Information:
Title
Long Term Immunogenicity of IC51 Vaccine 24 Months After the Primary Vaccination
Description
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
Time Frame
- 24 months
Secondary Outcome Measure Information:
Title
SPR 24 Months After the Primary Vaccination (Observed)
Description
Persistence of immunogenicity (SPR) at M24 (observed) defined as :
positive (persistent): Subjects
with a non-missing, positive seroconversion at D56 (Study IC51-304), and
who did not receive a booster dose at Visit 2 (M11) or Visit 4 (M23), and
with a non-missing, SP positive PRNT50 result at Visit 1 (M6) or Visit 3 (M12), and
with a non-missing, SP positive PRNT50 result at Visit 5 (M24)
negative (non-persistent): Subjects
with missing or negative seroconversion at D56 (Study IC51-304), or
who did receive a booster dose at Visit 2 (M11) or at Visit 4 (M23), or
with a non-missing, SP negative PRNT50 result at Visit 1 (M6) or Visit 3 (M12), or
with a missing PRNT50 result at both Visit 1 (M6) and Visit 3 (M12), or
with a non-missing, SP negative PRNT50 result at Visit 5 (M24)
Time Frame
24 months
Title
Persistent and Actual SPR 6, 12 and 24 Months After Primary Vaccination
Time Frame
- 24 months
Title
Persistent and Actual GMT 6, 12 and 24 Months After Primary Vaccination
Time Frame
24 months
Title
SCR 1 Month After the Booster Doses
Time Frame
1 month
Title
GMT 1month After Booster Doses
Time Frame
1 month
Title
Safety Profile of IC51
Time Frame
study duration
10. Eligibility
Sex
All
Minimum Age & Unit of Time
18 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria:
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.
Exclusion Criteria:
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
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Susanne Eder
Organizational Affiliation
Valneva Austria GmbH
Official's Role
Study Director
12. IPD Sharing Statement
Learn more about this trial
Long Term Persistence and Effect of a Booster Dose of the Japanese Encephalitis Vaccine IC51
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