Comparative immunogenicity and safety of different multivalent component pertussis vaccine formulations and a 5-component acellular pertussis vaccine in infants and toddlers: A randomized, controlled, open-label, multicenter study

► Use of combination vaccines (same manufacturer) with different numbers of antigens. ► Compared fourth dose DTaP, Hib (DTaP-IPV/Hib infant series) with 4 doses DTaP, Hib. ► Compared 4 doses DTaP-IPV/Hib and 4 doses DTaP-IPV, Hib with 4 doses DTaP, Hib. ► Combination vaccines safety/immunogenicity comparable to separate components. ► Study provided data to support combination vaccine interchangeability.