title: Comparison of 2 different regimens for reactogenicity, safety, and immunogenicity of the live attenuated oral rotavirus vaccine RIX4414 coadministered with oral polio vaccine in South African infants.
abstract: BACKGROUND
  A phase II, randomized, double-blind, placebo-controlled study was conducted in South Africa during 2003-2004 to evaluate the safety, reactogenicity, and immunogenicity of 2 regimens of the live attenuated oral human rotavirus vaccine RIX4414 when coadministered with the Expanded Program on Immunization childhood vaccines, including oral polio vaccine.
  
  
  METHODS
  Healthy infants were randomized (2:2:1) to receive either 2 doses of RIX4414 (n = 190; at 10 and 14 weeks, with placebo at 6 weeks), 3 doses of RIX4414 (n = 189; at 6, 10, and 14 weeks), or 3 doses of placebo (n = 96), all with concomitant routine vaccinations. The antirotavirus IgA seroconversion rate was assessed using enzyme-linked immunosorbent assay at 2 months after the last dose of RIX4414 or placebo. Antipolio types 1, 2, and 3 antibodies were measured using a virus neutralization assay. Solicited symptoms were recorded for 15 days after each dose.
  
  
  RESULTS
  The antirotavirus IgA seroconversion rates were similar in the RIX4414 2- and 3-dose groups (44.3% and 44.4%, respectively; P = .544, by 1-sided Fisher exact test) and antirotavirus IgA geometric mean concentrations were also comparable. Seroprotection rates for antipolio types 1, 2, and 3 antibodies were high (93%-100%) and were not significantly different among groups. Solicited symptoms reported within 15 days after vaccination were similar in all groups.
  
  
  CONCLUSIONS
  The immune seroconversion response to the RIX4414 vaccine with 3 doses was not superior to the 2-dose regimen. There was no interference by either regimen with antibody response to oral polio vaccine, and RIX4414 was well tolerated when given with routine vaccinations.
authors.affiliation: MRC Diarrhoeal Pathogens Research Unit, University of Limpopo, Pretoria, Republic of South Africa. dsteele@path.org
authors.forename: A D
authors.initials: AD
authors.lastname: Steele
authors.forename: J
authors.initials: J
authors.lastname: Reynders
authors.forename: F
authors.initials: F
authors.lastname: Scholtz
authors.forename: P
authors.initials: P
authors.lastname: Bos
authors.forename: M C
authors.initials: MC
authors.lastname: de Beer
authors.forename: J
authors.initials: J
authors.lastname: Tumbo
authors.forename: C F
authors.initials: CF
authors.lastname: Van der Merwe
authors.forename: A
authors.initials: A
authors.lastname: Delem
authors.forename: B
authors.initials: B
authors.lastname: De Vos
mesh_terms: D000284:Administration, Oral; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000097:blood; D004311:Double-Blind Method; D004347:Drug Interactions; D005260:Female; D006801:Humans; D007115:Immunization Schedule; D007070:Immunoglobulin A / Q000097:blood; D007223:Infant; D008297:Male; D011051:Poliomyelitis / Q000453:epidemiology / Q000517:prevention & control*; D011055:Poliovirus Vaccine, Oral / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology*; D012400:Rotavirus Infections / Q000453:epidemiology / Q000517:prevention & control*; D022243:Rotavirus Vaccines / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology*; D013019:South Africa / Q000453:epidemiology; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D007070:Immunoglobulin A; D011055:Poliovirus Vaccine, Oral; D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated