Phase IV Study of Concomitant Administration of the sIPV and HepA

This study is a randomized, open-labeled phase IV clinical trial to evaluate the immunogenicity and safety of concomitant administration of sIPV and HepA-L or HepA-I in children aged 18 months. The primary immunogenicity endpoints in all groups are the seroconversion rates of type I, II, and III anti-poliovirus neutralizing antibodies and the seroconversion rate of anti-hepatitis A virus antibodies 30 days after the final administration. The secondary immunogenicity endpoints are (1) the GMT/GMC of type I, II, and III anti-poliovirus neutralizing antibodies as well as the anti-hepatitis A virus antibodies 30 days after the final administration; (2) the seropositive rates of the anti-hepatitis A virus antibodies 30 days after the final administration; (3) the GMFI of type I, II, and III anti-poliovirus neutralizing antibodies as well as the anti-hepatitis A virus antibodies 30 days after the final administration. The secondary safety endpoints are the incidence of adverse events (AEs) within 30 minutes after each injection, the incidence of solicited local and systematic AEs in the period of solicitation after each injection, the incidence of unsolicited AEs in 30 days after each injection, the incidence of AEs in 30 days after each injection, and the incidence of serious adverse events in 6 months after administrations.