title: Efficacy, Immunogenicity and Safety of a Human Rotavirus Vaccine RIX4414 in Singaporean Infants.
abstract: BACKGROUND
  This was the first study conducted to evaluate the efficacy of 2 oral doses of the human rotavirus vaccine, RIX4414 in Singaporean infants during the first 3 years of life.
  
  
  METHODS
  Healthy infants, 11 to 17 weeks of age were enrolled in this randomised (1:1), double-blinded, placebo-controlled study to receive 2 oral doses of RIX4414 vaccine/placebo following a 0-, 1-month schedule. Vaccine efficacy against severe rotavirus (RV) gastroenteritis (Vesikari score ≥11) caused by wild-type RV strains from a period starting from 2 weeks post-Dose 2 until 2 and 3 years of age was calculated with 95% confidence interval (CI). Immunogenicity and safety of the vaccine were also assessed.
  
  
  RESULTS
  Of 6542 infants enrolled, 6466 were included in the efficacy analysis and a subset of 100 infants was included in the immunogenicity analysis. Fewer severe RV gastroenteritis episodes were reported in the RIX4414 group when compared to placebo at both 2 and 3 year follow-up periods. Vaccine efficacy against severe RV gastroenteritis at the respective time points were 93.8% (95% CI, 59.9 to 99.9) and 95.2% (95% CI, 70.5 to 99.9). One to 2 months post-Dose 2 of RIX4414, 97.5% (95% CI, 86.8 to 99.9) of infants seroconverted for anti-RV IgA antibodies. The number of serious adverse events recorded from Dose 1 until 3 years of age was similar in both groups.
  
  
  CONCLUSIONS
  Two oral doses of RIX4414 vaccine was immunogenic and provided high level of protection against severe RV gastroenteritis in Singaporean children, during the first 3 years of life when the disease burden is highest.
authors.affiliation: Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
authors.forename: Kong Boo
authors.initials: KB
authors.lastname: Phua
authors.forename: Fong Seng
authors.initials: FS
authors.lastname: Lim
authors.forename: Seng Hock
authors.initials: SH
authors.lastname: Quak
authors.forename: Bee Wah
authors.initials: BW
authors.lastname: Lee
authors.forename: Yee Leong
authors.initials: YL
authors.lastname: Teoh
authors.forename: Pemmaraju V
authors.initials: PV
authors.lastname: Suryakiran
authors.forename: Htay Htay
authors.initials: HH
authors.lastname: Han
authors.forename: Hans L
authors.initials: HL
authors.lastname: Bock
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology; D004311:Double-Blind Method; D005260:Female; D005759:Gastroenteritis / Q000517:prevention & control* / Q000821:virology; D006801:Humans; D000071497:Immunogenicity, Vaccine; D007070:Immunoglobulin A / Q000276:immunology; D007223:Infant; D008297:Male; D012401:Rotavirus / Q000276:immunology; D012400:Rotavirus Infections / Q000517:prevention & control*; D022243:Rotavirus Vaccines / Q000276:immunology / Q000627:therapeutic use*; D012846:Singapore; D016896:Treatment Outcome; D014613:Vaccines, Attenuated / Q000276:immunology / Q000627:therapeutic use
chemical_list: D000914:Antibodies, Viral; D007070:Immunoglobulin A; C492457:RIX4414 vaccine; D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated