Study to Evaluate the Immunogenicity, Safety, and Tolerability of a Tick-Borne Encephalitis (TBE) Vaccine in Healthy Japanese Participants 1 Year of Age and Older

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether considered related to the study intervention. Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 1 month after any Dose

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether considered related to the study intervention. Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 1 month after Dose 1

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether considered related to the study intervention. Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 1 month after Dose 2

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product.

An AE was defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether considered related to the study intervention. Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 1 month after Dose 3

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product. Here, Overall Number of Participants Analyzed signifies participants who were evaluable for this outcome measure.

LR:participant or legally acceptable representative/parent/legal guardian using an electronic diary (e-diary). LR included redness, swelling and pain at injection site. Redness and swelling were measured using measuring device units. 1 measuring device unit =0.5 centimeter(cm). Redness and swelling were graded as: for participants \>=12 years of age, mild(greater than\[\>\] 2.0 to 5.0 cm), moderate(\>5.0 to 10.0 cm) and severe (\>10.0 cm); for participants less than (\<)12 years of age, mild(\>0 to 2.0 cm), moderate(\>2.0 to7.0 cm) and severe(\>7.0 cm). Pain at the injection site was graded as: for participants \>2 years of age, mild(does not interfere with activity), moderate(interferes with activity) and severe(prevents daily activity); for participants less than or equal to (\<=)2 years of age, mild(hurts if gently touched) moderate(hurts if gently touched with crying) and severe(causes limitation of limb movement). Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 7 days after Dose 1

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product.

Local reactions were collected by participant or legally acceptable representative/parent/legal guardian using an e-diary. Local reactions included redness, swelling and pain at the injection site. Redness and swelling were measured using measuring device units. 1 measuring device unit =0.5 cm. Redness and swelling were graded as: for participants \>=12 years of age, mild (\> 2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm) and severe (\>10.0 cm); for participants \<12 years of age, mild (\>0 to 2.0 cm), moderate (\>2.0 to 7.0 cm) and severe (\>7.0 cm). Pain at the injection site was graded as: for participants \>2 years of age, mild (does not interfere with activity), moderate (interferes with activity) and severe (prevents daily activity); for participants \<=2 years of age, mild (hurts if gently touched) moderate (hurts if gently touched with crying) and severe (causes limitation of limb movement). Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 7 days after Dose 2

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product.

Local reactions were collected by participant or legally acceptable representative/parent/legal guardian using an e-diary. Local reactions included redness, swelling and pain at the injection site. Redness and swelling were measured using measuring device units. 1 measuring device unit =0.5 cm. Redness and swelling were graded as: for participants \>=12 years of age, mild (\> 2.0 to 5.0 cm), moderate (\>5.0 to 10.0 cm) and severe (\>10.0 cm); for participants \<12 years of age, mild (\>0 to 2.0 cm), moderate (\>2.0 to 7.0 cm) and severe (\>7.0 cm). Pain at the injection site was graded as: for participants \>2 years of age, mild (does not interfere with activity), moderate (interferes with activity) and severe (prevents daily activity); for participants \<=2 years of age, mild (hurts if gently touched) moderate (hurts if gently touched with crying) and severe (causes limitation of limb movement). Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Within 7 days after Dose 3

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product. Here, Overall Number of Participants Analyzed signifies participants who were evaluable for this outcome measure.

An SAE was defined as any untoward medical occurrence that, at any dose that resulted in death; was life-threatening (immediate risk of death); required inpatient hospitalization or prolongation of existing hospitalization; resulted in persistent disability/incapacity (substantial disruption of the ability to conduct normal life functions); resulted in congenital anomaly/birth defect or that is considered to be an important medical event. Percentage of participants with SAEs and the exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: From Day 1 up to end of study (up to approximately 13 months)

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product.

SE:participants or legally acceptable representative/parent/legal guardian using e-diary & included fever:temperature \>=37.5 degree Celsius(C)&categorized as 37.5to38.4, 38.5 to 38.9,39.0 to 40.0,\>40.0 degree C.Fatigue, headache, muscle pain, joint pain: mild(didn't interfere with activity), moderate(some interference with activity), severe(prevented daily activity). Vomiting: mild(1-2 times in 24 hours\[hrs\]), moderate(\>2 times in 24hrs), severe(required intravenous hydration). Diarrhea: mild(2-3 loose stools in 24hrs), moderate(4-5 loose stools in 24hrs), severe(6 or more loose stools in 24hrs). Decreased appetite:mild(decreased interest in eating),moderate(decreased oral intake), severe(refusal to feed).Drowsiness: mild(Increased sleeping bouts),moderate(slightly subdued interfering with daily activity),severe(disabling not interested in usual daily activity).Irritability:mild(easily consolable), moderate(required increased attention),severe(inconsolable, crying can't be comforted).

Time frame: Within 7 days after Dose 1

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product. Here, 'Number Analyzed' signifies those participants who were evaluable for the specified rows.

SE:participants or a legally acceptable representative/parent/legal guardian using e-diary and included fever:temperature \>=37.5 degreeC & categorized as 37.5 to 38.4,38.5 to 38.9,39.0 to 40.0,\>40.0 degreeC.Fatigue, headache, muscle pain, joint pain: mild(didn't interfere with activity),moderate(some interference with activity), severe(prevented daily activity). Vomiting: mild(1-2 times in 24 hours\[hrs\]), moderate(\>2 times in 24hrs),severe(required intravenous hydration).Diarrhea: mild(2-3 loose stools in 24hrs), moderate(4-5 loose stools in 24hrs), severe(6 or more loose stools in 24hrs). Decreased appetite: mild(decreased interest in eating), moderate(decreased oral intake), severe(refusal to feed). Drowsiness: mild(Increased sleeping bouts), moderate(slightly subdued interfering with daily activity), severe(disabling not interested in usual daily activity).Irritability: mild(easily consolable), moderate(required increased attention),severe(inconsolable, crying can't be comforted).

Time frame: Within 7 days after Dose 2

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product. Here, 'Number Analyzed' signifies those participants who were evaluable for the specified rows.

Systemic events collected by participant using e-diary and included fever defined as temperature \>=37.5 degree C and categorized as 37.5 to 38.4, 38.5 to 38.9, 39.0 to 40.0, \>40.0 degree C. Fatigue, headache, muscle pain, joint pain: mild(didn't interfere with activity), moderate(some interference with activity), severe(prevented daily activity). Vomiting: mild(1-2 times in 24 hours\[hrs\]), moderate(\>2 times in 24hrs), severe(required intravenous hydration). Diarrhea: mild(2-3 loose stools in 24hrs), moderate(4-5 loose stools in 24hrs), severe(6 or more loose stools in 24hrs). Decreased appetite: mild(decreased interest in eating), moderate(decreased oral intake), severe(refusal to feed). Drowsiness: mild(Increased sleeping bouts), moderate(slightly subdued interfering with daily activity), severe(disabling not interested in usual daily activity). Irritability: mild(easily consolable), moderate(required increased attention), severe(inconsolable, crying can't be comforted).

Time frame: Within 7 days after Dose 3

Population: Safety analysis population included all enrolled participants who received at least 1 dose of the investigational product. Here, Overall Number of Participants Analyzed signifies participants who were evaluable for this outcome measure and 'Number Analyzed' signifies those participants who were evaluable for the specified rows.

Seropositivity rate based on the immune response was determined by neutralization test (NT). Participants who achieved tick-borne encephalitis virus (TBEV) NT titers \>=1: 10 were considered as seropositive. Exact 2-sided 95% confidence interval (CI) based on the Clopper and Pearson method was presented.

Time frame: 4 weeks after Dose 3

Population: Evaluable immunogenicity (EI) population: Participants who received all 3 doses of the investigational product, had blood drawn for assay testing within the specified time frame for baseline and 4 weeks after the third vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the third vaccination visit, were NT seronegative at baseline, and had no major protocol violations.

GMFRs and the corresponding 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). The LLOQ value for NT was 5. Assay results below the LLOQ were set to 0.5 × LLOQ.

Time frame: From Baseline to 4 weeks after Dose 2

Population: Evaluable immunogenicity population for the second dose: Participants who received the first 2 doses of the investigational product, had blood drawn for assay testing within the specified time frame for baseline and 4 weeks after the second vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the second vaccination visit, were NT seronegative at baseline, and had no major protocol violations.

GMFRs and the corresponding 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). The LLOQ value for NT was 5. Assay results below the LLOQ were set to 0.5 × LLOQ.

Time frame: From 4 weeks after Dose 2 to 4 weeks after Dose 3

Population: EI population: Participants who received all 3 doses of the investigational product, had blood drawn for assay testing within specified time frame for baseline and 4 weeks after the third vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the third vaccination visit, were NT seronegative at baseline, and had no major protocol violations.

GMFRs and the corresponding 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the Student t distribution). The LLOQ value for NT was 5. Assay results below the LLOQ were set to 0.5 × LLOQ.

Time frame: From Baseline to 4 weeks after Dose 3

Population: EI population: Participants who received all 3 doses of the investigational product, had blood drawn for assay testing within specified time frame for baseline and 4 weeks after the third vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the third vaccination visit, were NT seronegative at baseline, and had no major protocol violations.

GMTs and associated 2-sided 95% CIs were calculated as the mean of the assay results on the natural logarithmic scale based on Student's t distribution and then exponentiating the results. The lower limit of quantitation (LLOQ) value for NT was 5. Assay results below the LLOQ were set to 0.5 × LLOQ.

Time frame: 4 weeks after Dose 2 and Dose 3

Population: EI population: Participants who received all 3 doses of the investigational product, had blood drawn for assay testing within specified time frame for baseline and 4 weeks after the third vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the third vaccination visit, were NT seronegative at baseline, and had no major protocol violations.

The LLOQ value for NT was 5. Assay results below the LLOQ were set to 0.5 × LLOQ. Percentage of participants with NT\>=LLOQ and exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: Before Dose 1, 4 weeks after Dose 2, Before Dose 3 and 4 weeks after Dose 3

Population: EI population: Participants who received all 3 doses of the investigational product, had blood drawn for assay testing within specified time frame for baseline and 4 weeks after the third vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the third vaccination visit, were NT seronegative at baseline, and had no major protocol violations.

Seropositivity rate based on the immune response was determined by NT. Participants who achieved TBEV NT titers \>=1: 10 were considered as seropositive. Exact 2-sided 95% CI based on the Clopper and Pearson method was presented.

Time frame: 4 weeks after Dose 2

Population: Evaluable immunogenicity (EI) population for the second dose: Participants who received the first 2 doses of the investigational product, had blood drawn for assay testing within the specified time frame for baseline and 4 weeks after the second vaccination, had valid and determinate assay result (NT titer) at baseline and 4 weeks after the second vaccination visit, were NT seronegative at baseline, and had no major protocol violations.