title: Immunogenicity and Safety of Yellow Fever Vaccine (Stamaril) When Administered Concomitantly With a Tetravalent Dengue Vaccine Candidate in Healthy Toddlers at 12-13 Months of Age in Colombia and Peru: A Randomized Trial.
abstract: Dengue and yellow fever (YF) viruses are closely related members of the Flaviviridae family. Given the inherent similarities between the YF vaccine and dengue vaccine (CYD-TDV) candidate, it is possible that the latter could interfere with the response to the licensed YF vaccine when coadministered.
  
  
  
  In this randomized, observer-blind, controlled, phase III trial, conducted in Colombia and Peru, 787 toddlers were administered YF vaccine concomitantly with CYD-TDV (group 1) or placebo (group 2), followed by CYD-TDV after 6 and 12 months. YF and dengue neutralizing antibody titers were determined using a 50% plaque reduction neutralization test. Noninferiority was demonstrated if the lower limit of the 2-sided 95% confidence interval of the difference in seroconversion rates [(YF + CYD-TDV) - YF alone] was greater than -10%. The safety of both vaccines was also assessed.
  
  
  
  Concomitant administration of YF with either CYD-TDV or placebo yielded YF seroconversion rates of 100.0% and 99.7%, respectively. The difference in YF seroconversion rates between the 2 groups was 0.33% (95% confidence interval:0.98; 1.87), demonstrating that the immune response against YF administered concomitantly with CYD-TDV was noninferior to YF administered with placebo. After 2 injections of CYD-TDV, the percentage of participants with dengue titres ≥10 (1/dil) for the 4 dengue serotypes were 91.2%-100% for group 1 and 97.2%-100% in group 2. There were no safety concerns during the study period.
  
  
  
  Concomitant administration of YF vaccine with CYD-TDV has no relevant impact on the immunogenicity or safety profile of the YF vaccine.
authors.affiliation: From the *Centro de Estudios en Infectología Pediátrica, Cali, Colombia; †Instituto de Investigación Nutricional, Lima, Perú; ‡Clinical Development, Sanofi Pasteur, Montevideo, Uruguay; §Clinical Development, Sanofi Pasteur, Marcy l'Etoile, France; and ¶Clinical Development, Sanofi Pasteur, Swiftwater, Pennsylvania.
authors.forename: Pio
authors.initials: P
authors.lastname: López
authors.forename: Claudio F
authors.initials: CF
authors.lastname: Lanata
authors.forename: Betzana
authors.initials: B
authors.lastname: Zambrano
authors.forename: Margarita
authors.initials: M
authors.lastname: Cortés
authors.forename: Teresa
authors.initials: T
authors.lastname: Andrade
authors.forename: Isabel
authors.initials: I
authors.lastname: Amemiya
authors.forename: Cynthia
authors.initials: C
authors.lastname: Terrones
authors.forename: Ana I
authors.initials: AI
authors.lastname: Gil
authors.forename: Hector
authors.initials: H
authors.lastname: Verastegui
authors.forename: Viviana
authors.initials: V
authors.lastname: Marquez
authors.forename: Denis
authors.initials: D
authors.lastname: Crevat
authors.forename: John
authors.initials: J
authors.lastname: Jezorwski
authors.forename: Fernando
authors.initials: F
authors.lastname: Noriega
mesh_terms: D003105:Colombia / Q000453:epidemiology; D053059:Dengue Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010568:Peru / Q000453:epidemiology; D014611:Vaccination / Q000009:adverse effects / Q000706:statistics & numerical data*; D022341:Yellow Fever Vaccine / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*
chemical_list: D053059:Dengue Vaccines; D022341:Yellow Fever Vaccine