Immunogenicity and Safety of the Japanese Encephalitis Vaccine IC51 (IXIARO®, JESPECT®) in a Pediatric Population in Non-endemic Countries

• Rate of subjects with serious adverse events (SAEs) and medically attended AEs up to Month 7 after the first vaccination [ Time Frame: up to Month 7 ] [ Designated as safety issue: Yes ]
• Rate of subjects with solicited local and systemic aEs assessed with a subject diary for 7 consecutive days after each vaccination [ Time Frame: 7 days ] [ Designated as safety issue: Yes ]
• Rate of subjects with unsolicited AEs up to day 56 and up to Month 7 after the first vaccination [ Time Frame: up to Day 56 and upt to Month 7 ] [ Designated as safety issue: Yes ]
• Rate of subjects with abnormal laboratory parameters up to Day 56 and up to Month 7 after the first vaccination [ Time Frame: up to Day 56 and up to Month 7 ] [ Designated as safety issue: Yes ]
• SCRs as defined as percentage of subjects with JEV neutralizing antibody titers of PRNT 50 >= 1:10 at Day 56 and Month 7, measured using a validated Plaque Reduction Neutralization Test (PRNT) [ Time Frame: at Day 56 and Month 7 ] [ Designated as safety issue: Yes ]
• GMTs for JEV neutralizing antibodies measured using a validated PRNT at Day 56 and Month 7 [ Time Frame: at Day 56 and Month 7 ] [ Designated as safety issue: Yes ]
• SCRs and GMTs at Day 56 and Month 7 stratified according to dose gropus and age groups [ Time Frame: at Day 56 and Month 7 ] [ Designated as safety issue: Yes ]

• SCRs and GMTs at Day 56 and Month 7 stratified according to dose groups, age groups, TBE vaccination history, travel to JE endemic areas, travel to JE endemic areas before Day 56, as well as travel to JE endemic areas after Day 56. [ Time Frame: at Day 56 and Month 7 ] [ Designated as safety issue: Yes ]
• Rate of subjects with SAEs and medically attended AEs up to Day 56 and up to Month 7 after the first vaccination [ Time Frame: until Day 56 and up to Month 7 ] [ Designated as safety issue: Yes ]
• Rate of subjects with solicited local and systemic AEs assessed with a subject diary for 7 consecutive days after each vaccination. [ Time Frame: study duration ] [ Designated as safety issue: Yes ]
• Rate of subjects with unsolicited AEs up to Day 56 and up to Month 7 after the first vaccination. [ Time Frame: study duration ] [ Designated as safety issue: Yes ]
• Rate of subjects with abnormal laboratory parameters (hematology, serum chemistry, urinalysis) up to Day 56 and up to Month 7 after the first vaccination. [ Time Frame: until Day 56 and up to Month 7 ] [ Designated as safety issue: Yes ]

The primary objective is to assess the safety profile of IC51 in a pediatric population from regions where JEV is not endemic

• Biological: IC51
  0.25 ml, 2 intramuscular vaccinations at Day 0 and Day 28
• Biological: IC51
  0.5 ml, 2 intramuscular vaccinations at Day 0 and 28
• Biological: IC51
  0.5 ml, 2 i.m. vaccinations at Day 0 and 28

• Experimental: >=2 months to <3 years
  IC51 0.25 ml, 2 intramuscular vaccinations at Day 0 and Day 28
  Intervention: Biological: IC51
• Experimental: >=12 to <18 years
  IC51, 0.5 ml, 2 intramuscular vaccinations at Day 0 and 28
  Intervention: Biological: IC51
• Experimental: >=3 to <12 years
  IC51, 0.5 ml, 2 i.m. vaccinations at Day 0 and 28
  Intervention: Biological: IC51

Inclusion Criteria:

• Male or female healthy children and adolescents aged >=2 months to <18 years at the time of first vaccination
• Written informed consent by the subject's legal representative(s), according to local requirements, and written informed assent of the subject, if applicable
• Female subjects: either no childbearing potential or negative pregnancy test. For females after menarche willingness to practice a reliable method of contraception.
• The subject is planning to travel to an area where JE is endemic after completion of the vaccination schedule. Exposure to JE should be avoided until 1 week after the second IC51 dose and subjects should return from travel to JE endemic areas before the Month 7 visit. The planned travel to JE endemic areas should not interfere with the study visits and can take place between Visit 2 + 7 days to Month 7.

Exclusion Criteria:

• Clinical manifestation or history of any Flavivirus disease
• Vaccination against JE (except within this protocol), Yellow fever, West Nile virus and Dengue at any time prior or during the study
• History of immunodeficiency or immunosuppressive therapy
• Known HIV, HBV or HCV infection
• History of hypersensitivity reactions to other vaccines
• Acute febrile infection at each visit during which the subject receives a vaccination
• Active or passive immunization within 1 week before and 1 week after each IC51 vaccination.