Japanese Encephalitis
Conditions
Brief summary
The study investigates long-term immunity and safety of IC51 (IXIARO®, JESPECT®) in a pediatric population vaccinated in the parent study IC51-322.
Interventions
PROCEDUREBlood draw
blood draw at Month 12, Month 24 and Month 36.
BIOLOGICALIC51 has given in the parent study IC51-322
No more vaccinations in IC51-324 since this a study for long-term follow-up on safety and immunogenicity after vaccinations in parent study IC51-322.
Sponsors
Valneva Austria GmbH
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
9 Months to 20 Years
Healthy volunteers
Yes
Inclusion criteria
* Subjects who have received two vaccinations in study IC51 322. (2) Subjects who were enrolled as part of the immunogenicity subgroup of study IC51-322. * Male or female healthy subjects aged ≥ 9 months to \< 21 years at the time of enrolment into this study. * Written informed consent by the subject, the subject's legal representative(s), according to local requirements, and written informed assent of the subject, if applicable.
Exclusion criteria
* History of or clinical manifestation of any Flavivirus disease during study IC51-322. * Vaccination against JE virus (JEV) (except with IC51) at any time prior or planned during this study. * Participation in another study with an investigational product during study IC51-322 or IC51-324. * History of or development of any immunodeficiency including post-organtransplantation after inclusion into study IC51-322. * History of or development of an autoimmune disease during study IC51-322. * Administration of chronic (defined as more than 14 days) immunosuppressants or other immune-modifying medications started during study IC51-322 up to first visit of study IC51-324. (For corticosteroids this means prednisone or equivalent at \>= 0.05 mg/kg/day. Topical or inhaled steroids are allowed). * Known infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV). * Illicit drug use and/or a history of drug or alcohol addiction and/or current drug or alcohol addiction. * Inability or unwillingness by the legal representative(s) and/or the subject (where applicable) to provide informed consent/assent and to abide by the requirements of the study. * Persons who are committed to an institution (by virtue of an order issued either by the judicial or the administrative authorities).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Month 12 After the First IC51 Vaccination (in Study IC51-322) | Month 12 | Rate of subjects with PRNT50 titers of ≥ 1:10 at Month 12 after the first IC51 vaccination (in study IC51-322) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| GMT for JEV Neutralizing Antibodies Measured Using the PRNT at Month 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 12, 24 and 36 | GMT for JEV neutralizing antibodies measured using the PRNT at Month 12, 24 and 36 after the first IC51 vaccination (in study IC51-322) |
| Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Months 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 24, 36 | Rate of subjects with PRNT50 titers of ≥ 1:10 at Months 24 and 36 after the first IC51 vaccination (in study IC51-322) |
| Rate of Subjects With SAEs Following Immunization up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Months 12, 24 and 36 | Rate of subjects with SAEs following immunization up to Months 12, 24 and 36 after the first IC51 vaccination (in study IC51-322) |
| Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Months 12, 24 and 36 | Rate of subjects with AEs and medically attended AEs up to Months 12, 24 and 36 after the first IC51 vaccination (in study IC51-322). |
Countries
Australia, Germany, United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| No Treatment subjects will be followed up on immunity (analysis of blood samples) and safety
Blood draw: blood draw at Month 12, Month 24 and Month 36.
IC51 was given in the parent study IC51-322: No more vaccinations in IC51-324 since this a study for long-term follow-up on safety and immunogenicity after vaccinations in parent study IC51-322. | 23 |
| Total | 23 |
Baseline characteristics
| Characteristic | No Treatment |
|---|---|
| Age, Continuous | 14.3 years STANDARD_DEVIATION 4.3 |
| Sex: Female, Male Female | 11 Participants |
| Sex: Female, Male Male | 12 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 8 / 23 |
| serious Total, serious adverse events | 2 / 23 |
Outcome results
Primary
Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Month 12 After the First IC51 Vaccination (in Study IC51-322)
Rate of subjects with PRNT50 titers of ≥ 1:10 at Month 12 after the first IC51 vaccination (in study IC51-322)
Time frame: Month 12
Population: intention to treat population; assessment of seroprotection \~1 year post primary vaccination series in parent study IC51-322
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| No Treatment | Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Month 12 After the First IC51 Vaccination (in Study IC51-322) | 89.5 percentage of participants |
Secondary
GMT for JEV Neutralizing Antibodies Measured Using the PRNT at Month 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322)
GMT for JEV neutralizing antibodies measured using the PRNT at Month 12, 24 and 36 after the first IC51 vaccination (in study IC51-322)
Time frame: Month 12, 24 and 36
Population: Intent to Treat Population
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| No Treatment | GMT for JEV Neutralizing Antibodies Measured Using the PRNT at Month 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 12 - Visit 2 | 47.8 Titer |
| No Treatment | GMT for JEV Neutralizing Antibodies Measured Using the PRNT at Month 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 24 - Visit 3 | 75.4 Titer |
| No Treatment | GMT for JEV Neutralizing Antibodies Measured Using the PRNT at Month 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 36 - Visit 4 | 60.8 Titer |
Secondary
Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322).
Rate of subjects with AEs and medically attended AEs up to Months 12, 24 and 36 after the first IC51 vaccination (in study IC51-322).
Time frame: Months 12, 24 and 36
Population: Safety Population
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| No Treatment | Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Medically attended - Month 12 - Visit 2 | 7 Participants |
| No Treatment | Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Medically attended - Month 24 - Visit 3 | 7 Participants |
| No Treatment | Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Medically attended - Month 36 - Visit 4 | 7 Participants |
| No Treatment | Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Any AE up to Month 12 | 8 Participants |
| No Treatment | Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Any AE up to Month 24 | 8 Participants |
| No Treatment | Rate of Subjects With AEs and Medically Attended AEs up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322). | Any AE up to Month 36 | 8 Participants |
Secondary
Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Months 24 and 36 After the First IC51 Vaccination (in Study IC51-322)
Rate of subjects with PRNT50 titers of ≥ 1:10 at Months 24 and 36 after the first IC51 vaccination (in study IC51-322)
Time frame: Month 24, 36
Population: Intent to Treat Population
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| No Treatment | Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Months 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Seroprotection Rate - Month 24 - Visit 3 | 91.3 percentage of participants |
| No Treatment | Rate of Subjects With PRNT50 Titers of ≥ 1:10 at Months 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Seroprotection Rate - Month 36 - Visit 4 | 89.5 percentage of participants |
Secondary
Rate of Subjects With SAEs Following Immunization up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322)
Rate of subjects with SAEs following immunization up to Months 12, 24 and 36 after the first IC51 vaccination (in study IC51-322)
Time frame: Months 12, 24 and 36
Population: Safety Population
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| No Treatment | Rate of Subjects With SAEs Following Immunization up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 12 - Visit 2 | 1 Participants |
| No Treatment | Rate of Subjects With SAEs Following Immunization up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 24 - Visit 3 | 2 Participants |
| No Treatment | Rate of Subjects With SAEs Following Immunization up to Months 12, 24 and 36 After the First IC51 Vaccination (in Study IC51-322) | Month 36 - Visit 4 | 2 Participants |