The clinical trial designed in this Study is a placebo-controlled, double-blinded Phase III and is aimed to evaluate the vaccine efficacy, safety, immunogenicity and immune persistence of cell culture-based inactivated EV71 vaccine in children age of 2 months to <6 years old. Two doses of Alum-adjuvanted 1.0 μg per dose of EV71 vaccine candidate will be administrated to subjects. The efficacy will be evaluated within a two year period after receiving 2-regimen vaccination by comparing the EV71-associated disease rates between the vaccine and placebo groups. Whereas, the immunogenicity will be assessed on Day 56 and Day 196, and the immune persistence will be evaluated on Day 392. Safety will be followed up to Day 392.
The objectives of this study are to evaluate the EV71vaccine efficacy, immune response and safety profiles after two injections of the cell culture-based inactivated EV71 vaccine with adjuvant Al(OH)3 administrated in pediatric population aged 2 months to 6 years old.