Immunogenicity, reactogenicity and safety of a human rotavirus vaccine (RIX4414) in Korean infants: A randomized, double-blind, placebo-controlled, phase IV study

Abstract

Rotavirus (RV) infection is the primary cause for childhood gastroenteritis worldwide. In Korea, RV infection is most common among children less than 5 y of age. This post-licensure study was conducted to further evaluate the RV vaccine (RIX4414) to provide additional local clinical data to the Korean Food and Drug Association. Healthy infants aged 6-12 weeks were enrolled to receive two doses of either RIX4414 or placebo as per 0, 1-2 mo schedule. Blood samples were collected before dose-1 and one month post-dose-2 of RIX4414/placebo to assess serum anti-RV IgA antibody concentrations using ELISA . Gastroenteritis stool samples were tested for the presence of RV using ELISA . RV positive samples were subjected to further analysis for G and P typing. Among 684 infants enrolled and vaccinated, 432 infants (RIX4414 = 318; placebo = 114) were included in the according-to-protocol cohort for immunogenicity. The anti-RV IgA antibody seroconversion rates in the RIX4414 group following one month post-dose-2 were 88.1% (95% CI: 84.0-91.4) and the corresponding geometric mean concentration in the RIX4414 group was 208.5 U/ml (95% CI: 174.2-249.5). Occurrence of solicited and unsolicited adverse events were similar in both, RIX4414 and placebo groups. None of the gastroenteritis stool samples tested positive for RV and no fatal SAE s were reported in either groups. The two-dose regimen of RIX4414 was observed to be immunogenic with a similar safety profile as compared with the placebo group, when administered to healthy Korean infants. © 2012 Landes Bioscience.