Article

Efficacy, safety and immunogenicity of a human rotavirus vaccine (RIX4414) in Hong Kong children up to three years of age: A randomized, controlled trial

Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, Hong Kong. Electronic address: .
Vaccine (Impact Factor: 3.49). 03/2013; 31(18). DOI: 10.1016/j.vaccine.2013.03.001
Source: PubMed

ABSTRACT BACKGROUND: A phase III, double-blind, randomized, controlled trial was conducted in Hong Kong to evaluate the efficacy, safety and immunogenicity of a human rotavirus vaccine, RIX4414 (Rotarix™) against severe rotavirus gastroenteritis in children up to three years of age. METHODS: Healthy infants aged 6-12 weeks were enrolled between 08-December-2003 and 31-August-2005 and received two oral doses of either RIX4414 vaccine (N=1513) or placebo (N=1512) given 2 months apart. Vaccine efficacy was assessed from two weeks post-Dose 2 until the children were two and three years of age. Anti-rotavirus IgA seroconversion rate was calculated pre-vaccination and 1-2 months post-Dose 2 using ELISA (cut-off=20U/mL) for 100 infants. Safety was assessed until the children were two years of age; serious adverse events (SAEs) were recorded throughout the study period. RESULTS: In children aged two and three years of life, vaccine efficacy against severe rotavirus gastroenteritis was 95.6% (95% CI: 73.1%-99.9%) and 96.1% (95% CI: 76.5%-99.9%), respectively. The seroconversion rate 1-2 months after the second dose of RIX4414 was 97.5% (95% CI: 86.8%-99.9%). At least one SAE was recorded in 439 and 477 infants who were administered RIX4414 and placebo, respectively (p-value=0.130). Six intussusception cases were reported (RIX4414=4; placebo=2) and none was assessed to be vaccine-related. CONCLUSION: RIX4414 was efficacious, immunogenic and safe in the prevention of rotavirus gastroenteritis for at least two years post-vaccination in Hong Kong children.

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