Safety and Immunogenicity of JECEVAX in Young Children

A dose escalating study with 3 different dosing regimens of the studied vaccine (JECEVAX- VABIOTECH-Vietnam) and a licensed vaccine (JEVAX-VABIOTECH-Vietnam) is conducted in Vietnamese children, aged 9 to 24 months to assess the safety and immunogenicity. Two hundred children are enrolled and randomly assigned into 4 groups (50 children/group), each of which receive 2 doses of study / control vaccine subcutaneously, at 10-12 days interval. Safety issues included immediate reaction at the site of injection and systemic reaction within 30 min of administration, solicited and unsolicited adverse events occurs from the first dose to 30 days after second dose; SAE (from start of first dose to 30 days after second dose), blood cell count, urea, ALT, AST. Immunogenicity outcomes include seroconversion of neutralizing antibodies (blood samples are taken prior to 1st dose and 20-22 days post 2nd dose).