Immunogenicity, reactogenicity and safety of the human rotavirus vaccine RIX4414 oral suspension (liquid formulation) in Finnish infants

Abstract

The lyophilized formulation of a human rotavirus vaccine, Rotarix™ (RIX4414) is highly immunogenic. In order to comply with the World Health Organization's (WHO) recommendation, a liquid formulation of the vaccine that does not require reconstitution was developed. The immunogenicity, reactogenicity and safety of the liquid formulation were compared with lyophilized formulation in two Finnish studies. In Study A infants aged 6-12 weeks received two doses of the lyophilized or liquid formulation of the vaccine or placebo following a 0,1 month schedule. In Study B, infants aged 10-17 weeks received two doses of either liquid or lyophilized formulation of the vaccine. In both studies, anti-rotavirus IgA antibodies were assessed pre-vaccination and one month post-Dose 2. In Study A, the anti-rotavirus seroconversion rate was 90% (95% CI: 81.2-95.6%) and 83.7% (95% CI: 74.2-90.8%) in the groups that received the liquid and the lyophilized formulation of RIX4414, respectively; the respective anti-rotavirus IgA seroconversion rates in Study B were 88.6% (95% CI: 86.1-90.8%) and 90.5% (95% CI: 86.2-93.8%). Reactogenicity and safety profiles of the two vaccine formulations were similar. Liquid formulation of the rotavirus vaccine allows greater flexibility in supply and reduces logistical costs.

Trial registration: ClinicalTrials.gov NCT00137930 NCT00382772.