Reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) vaccine, Boostrix™, is indicated for booster vaccination of children, adolescents and adults. The original prefilled disposable dTpa syringe presentation was recently replaced by another prefilled-syringe presentation with latex-free tip-caps and plunger-stoppers. 671 healthy adolescents aged 10-15 years who had previously received 5 or 6 previous DT(P)/dT(pa) vaccine doses, were randomized (1:1) to receive dTpa booster, injected using the new (dTpa-new) or previous syringe (dTpa-previous) presentations. Immunogenicity was assessed before and 1-month post-booster vaccination; safety/reactogenicity were assessed during 31-days post-vaccination. Non-inferiority of dTpa-new versus dTpa-previous was demonstrated for all antigens (ULs 95% CIs for GMC ratios ranged between 1.03-1.13). 1-month post-booster, immune responses were in similar ranges for all antigens with both syringe presentations. dTpa delivered using either syringe presentation was well-tolerated. These clinical results complement the technical data and support the use of the new syringe presentation to deliver the dTpa vaccine.
Trial registration: ClinicalTrials.gov NCT01362322.
Keywords: ANCOVA, analysis of co-variance; ATP, according to protocol; CI, confidence interval; El.U, Elisa units; FHA, filamentous hemagglutinin; GI, gastrointestinal; GMC, geometric mean concentration; IU, international units; LL, lower limit; PRN, pertactin; PT, pertussis toxin; SAE, serious adverse event; TVC, total vaccinated cohort; UL, upper limit; booster; dTpa, reduced-antigen-content diphtheria tetanus and acellular pertussis vaccine; diphtheria; pertussis; syringe presentation; tetanus.