Lot-to-lot consistency study of the fully liquid pentavalent DTwP-HepB-Hib vaccine Quinvaxem® demonstrating clinical equivalence, suitability of the vaccine as a booster and concomitant administration with measles vaccine

This double-blind, randomized study evaluated the immunogenicity and safety of three production lots of the fully liquid combination DTwP-Hep-Hib vaccine, Quinvaxem (R) (Crucell, The Netherlands) in 360 healthy infants aged 42-64 d old given at 6, 10 and 14 weeks of age (Core Study). The Core Study was followed by an open-label Booster Phase evaluating immunogenicity and safety of a booster dose of Quinvaxem (R) given with either concomitant or deferred measles vaccine in 227 infants who completed the Core Study. One month after the third dose of Quinvaxem (R) immune responses reflecting seroprotection or seroconversion were observed in more than 90% of infants for all three vaccine lots. Quinvaxem (R) elicited a strong booster response as demonstrated by a large increase in antibodies against all antigens, which appeared to be unaffected by concomitant administration of the measles vaccine. Safety results were in line with previous reports for Quinvaxem (R) with no unexpected adverse events (AEs) being reported. In the Core Study and Booster Phase, Quinvaxem (R) was well tolerated. No study vaccine-related serious AEs were reported. Thus, we conclude Quinvaxem (R) was immunogenic and well-tolerated when administered to infants according to a 6-10-14 week vaccination schedule. The three production lots had consistent reactogenicity and immunogenicity profiles. The booster dose of Quinvaxem (R) was also immunogenic and safe, regardless of whether a monovalent measles vaccine was administered concomitantly or one month later.