Japanese Encephalitis
Conditions
Brief summary
The objective is to assess the effect of a booster vaccination on immunogenicity of IC51 in terms of seroconversion rate.
Interventions
BIOLOGICALIC51
IC51, 6 mcg, intramuscular (i.m.) booster vaccination 15 months after the primary immunization
Sponsors
Valneva Austria GmbH
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Main Inclusion Criteria: * Healthy adults who completed the primary immunization in study IC51 309 * Male and female healthy subjects aged at least 18 years with written informed consent and either no childbearing potential or negative pregnancy test Main
Exclusion criteria
• History of immunodeficiency or immunosuppressive therapy, known Human Immunodeficiency Virus (HIV), or drug addiction including alcohol dependence
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Seroconversion Rate | at Month 12 after booster |
Secondary
| Measure | Time frame |
|---|---|
| Safety and Adverse Events | up to Month 12 after booster |
| Seroconversion | at D28 and Month 6 after booster |
| Geometric Mean Titer | D28, Month 6 and Month 12 after booster |
Countries
Austria, Germany
Participant flow
Recruitment details
subjects participating in preceeding study IC51-309 were contacted. First Subject In December 2007, Last Subject In March 2008; study sites: center of pharmacology and travel clinics
Pre-assignment details
subjects participating in study IC51-309 without major Protocol Deviations
Participants by arm
| Arm | Count |
|---|---|
| IC51 Booster Group IC51, 6 mcg, intramuscular (i.m.) booster vaccination 15 months after the primary immunization in study IC51-309 | 198 |
| Total | 198 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | acute infection after V0 | 1 |
| Overall Study | Lost to Follow-up | 1 |
| Overall Study | personal reason | 1 |
| Overall Study | planned vaccination against yellow fever | 1 |
Baseline characteristics
| Characteristic | IC51 Booster Group |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 1 Participants |
| Age, Categorical Between 18 and 65 years | 197 Participants |
| Age, Continuous | 31.2 years STANDARD_DEVIATION 9.9 |
| Region of Enrollment Austria | 103 participants |
| Region of Enrollment Germany | 95 participants |
| Sex: Female, Male Female | 104 Participants |
| Sex: Female, Male Male | 94 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 96 / 198 |
| serious Total, serious adverse events | 8 / 198 |
Outcome results
Primary
Seroconversion Rate
Time frame: at Month 12 after booster
Population: Intent-To-Treat Population which includes all subjects entered into the study who received the booster vaccination
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| IC51 Booster Group | Seroconversion Rate | 98.5 percent |
Secondary
Geometric Mean Titer
Time frame: D28, Month 6 and Month 12 after booster
Secondary
Safety and Adverse Events
Time frame: up to Month 12 after booster
Secondary
Seroconversion
Time frame: at D28 and Month 6 after booster