High rates of pertussis disease in adolescents suggest that additional boosting against pertussis would be beneficial. A combined acellular-pertussis-containing booster vaccine (dTpa-IPV; Boostrixtrade mark Polio, n =440) was compared to separately administered dTpa (Boostrixtrade mark) and inactivated polio virus (IPV; Imovax Polio((R)), n =219), and to DTPa-IPV (Infanrixtrade mark IPV, n =111) vaccine in a partially blind, randomised controlled trial in 10-14 year olds. One month after vaccination, seroprotection/seropositivity rates for all antigens were similar for all groups. Although pertussis and diphtheria antibody geometric mean antibody concentrations were higher after DTPa-IPV, all subjects had protective antibodies against diphtheria, tetanus and polio, and at least 97% had a vaccine response to pertussis antigens. Reactogenicity of dTpa-IPV was comparable to dTpa + IPV, but dTpa-IPV was generally better tolerated than DTPa-IPV. CONCLUSION: The combined reduced-antigen-content-diphtheria-tetanus-acellular-pertussis and IPV vaccine is immunogenic and well tolerated when administered to adolescents and could be used to improve the control of pertussis disease in this age group.