Lot-to-Lot Consistency of a Combined Hexavalent Diptheria-Tentanus-Acellular-Pertussis, Hepatitis B, Inactivated Polio and Haemophilus b Conjugate Vaccine, Adminstered to Healthy Chilean Infants at 2, 4 and 6 Months of Age

Objectives: To assess the safety, immunogenicity and lot consistency of a liquid hexavalent combined vaccine (DTaP-IPV-PRP~T-HBs, HEXAVAC®) (Sanofi-Pasteur MSD, France) administered to infants at 2, 4, and 6 months of age.Methods: A total of 1028 infants were vaccinated with one of 3 vaccine lots, in a randomized, double-blind fashion. Equivalence testing was used to compare post-vaccination seroprotection/seroconversion rates and geometric mean titers (GMTs) for each antigen between the three lots. Blood samples were drawn before vaccination and one month after the third dose. Local and systemic adverse events were monitored for 3 days following each injection.Results: Equivalence between lots was demonstrated for all antigens, on post-dose 3 seroprotection/seroconversion rates and GMTs. Reported rates of local and systemic adverse events tended to increase with subsequent doses. Altogether, 11.8% of the infants reported at least one adverse local event (mainly redness and induration/swelling) after the ...