study of a live attenuated japanese encephalitis chimeric virus vaccine (imojev™) compared to cd.jevax™ in toddlers

Conditions: Japanese Encephalitis; Japanese Encephalitis Virus Disease

Summary: the purpose of this study is to compare live attenuated japanese encephalitis chimeric virus vaccine (imojev™) with japanese encephalitis live attenuated vaccine (sa14 14 2 vaccine \[cd.jevax™\]) after a single dose vaccination to support product registration. primary objective: * to demonstrate the non-inferiority of the antibody response 28 days after administration of one dose of imojev™ compared to the antibody response 28 days after administration of one dose of the cd.jevax™ control vaccine. secondary objectives: * to describe the immune response to japanese encephalitis (je) in both vaccine groups using 50% plaque reduction neutralization assay (prnt50) assays before and after a single dose of imojev™ vaccine or a single dose of cd.jevax™ vaccine. * to describe the safety of vaccination in all subjects up to 28 days and all serious adverse events up to 6-month after vaccination.

all participants will receive a single dose of their assigned vaccination at visit 1 (day 0) and undergo immunogenicity assessment at day 28 post-vaccination. safety will be assessed from day of vaccination and up to 6 months post-vaccination.

Eligibility criteria:
inclusion criteria: * aged 12 to 24 months on the day of inclusion * in good general health, without significant medical history. * provision of informed consent form signed by at least one parent or other legally acceptable representative. * subject and parent/guardian able to attend all scheduled visits and comply with all trial procedures. exclusion criteria: * participation in another clinical trial investigating a vaccine, drug, medical device, or a medical procedure in the 4 weeks preceding the trial vaccination. * planned participation in another clinical trial during the present trial period. * known or suspected congenital or acquired immunodeficiency, or receipt of immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy within the preceding 6 months, or long-term systemic corticosteroids therapy. * known systemic hypersensitivity to any of imojev™ components or history of a life-threatening reaction to a vaccine containing any of the same substances and vaccination,known systemic hypersensitivity to cd.jevax® main components and the other components (including gelatin, kanamycin, and gentamicin). * chronic illness at a stage that could interfere with trial conduct or completion, in the opinion of the investigator. * receipt of blood or blood-derived products in the past 3 months, that might interfere with the assessment of the immune response. * previous vaccination against flavivirus disease, including japanese encephalitis (je). * administration of any anti-viral within 2 months preceding visit 01 and up to the 4 weeks following the trial vaccination. * receipt of any vaccine in the 4 weeks preceding the first trial vaccination, except for pandemic influenza vaccination, which may be received at least two weeks before the study vaccines. * planned receipt of any vaccine from the inclusion up to the 4 weeks following the trial vaccination. * history of central nervous system disorder or disease, including seizures. * planned receipt of any je vaccine during the course of the study. * history of flavivirus infection (confirmed either clinically, serologically or virologically). * administration of systemic corticosteroids for more than two consecutive weeks within the 4 weeks preceding vaccination. * febrile illness (temperature ≥38.0°c) or moderate or severe acute illness/infection 3 days before vaccination as well as the day of vaccination, according to investigator judgment. * thrombocytopenia or bleeding disorder contraindicated for vaccination with same administration route, or receipt of anticoagulants in the 3 weeks preceding inclusion.

Keywords: japanese encephalitis japanese encephalitis virus disease imojev™ cd.jevax™