Clinical Research Directory

Inclusion Criteria: 1. Healthy children who were enrolled in Part A1 (immunogenicity sub-study) of EV-BR1701, received two injections of either EnVAX-A71 or placebo, and had blood sample collected on Day 56 for primary immunogenicity endpoint analysis (the "evaluable" subjects). 2. The subject's guardian/legal representative is able and willing to comply with study procedures and provide signed informed consent. Exclusion Criteria: 1. History of bleeding disorder, hemostatic difficulties or significant bruising caused by phlebotomy since the last visit in EV-BR1701 main study. 2. Having been vaccinated with any EV71 vaccine products.