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

Background: Pentavalent and quadrivalent combination vaccine formulations from the same manufacturer (DTaP-IPV/Hib [PENTA], DTaP-IPV [QUAD]) were investigated as to whether they were sufficiently interchangeable to tailor use to local preference or availability. Methods: A randomized, controlled, open-label, 4-armed, multicenter study in healthy, full-term infants (42-89 days of age) was conducted in 38 centers across the United States. Participants were randomized 1:1:1:1 to a control vaccine group (3 doses DTaP, IPV, and Hib and at Dose 4 DTaP and Hib) and 3 combination vaccine groups: (1) 3 doses PENTA, then Dose 4 DTaP and Hib; (2) 4 QUAD doses and Hib; (3) 4 PENTA doses. Participants (. N=. 2167) were immunized at 2, 4, and 6 months of age, Dose 4 participants (. N=. 1832) at 15 months of age. Immunogenicity was assessed before Doses 1 and 4 and after Doses 3 and 4. Safety was assessed 30 days after each dose and through 180 days Post-Dose 4. Results: Antibody responses and geometric mean concentrations/geometric mean titers (GMCs/GMTs) elicited by each combination vaccine were noninferior (upper-bound 90% confidence interval of GMC/GMT ratios