Coadministration of RIX4414 oral human rotavirus vaccine does not impact the immune response to antigens contained in routine infant vaccines in the United States.

Objective: This study was conducted to confirm the absence of immune interference of 2 doses of RIX4414 (Rotarix) on routine infant vaccinations in the United States.

Study Design: A total of 484 healthy infants aged 6 to 12 weeks were randomly assigned to 1 of 2 groups to receive 3 doses of Pediarix (combined diphtheria-tetanus-acellular pertussis-hepatitis B-poliovirus vaccine [DTaP-HBV-IPV]), Prevnar (7-valent pneumococcal conjugate vaccine [PCV7]), and ActHIB (Haemophilus influenzae type b conjugate vaccine [Hib]) at 2, 4, and 6 months of age with RIX4414 either coadministered at 2 and 4 months (Co-ad) or administered separately at 3 and 5 months (Sep-ad). Serum antibodies were measured 1 month after dose 3 of the DTaP-HBV-IPV, PCV7, and Hib vaccines.

Results: Antibody responses to all antigens were similar in infants in both the Co-ad and Sep-ad groups. Seroprotective antibody concentrations against diphtheria, tetanus, hepatitis B, and poliovirus types 1, 2, and 3 were achieved by >or=97.9% of the infants in both groups. Antipolyribosyl ribitol phosphate antibody levels of >or=1.0 microg/mL were achieved by 88.3% to 89.4% of infants in both groups. In both groups, >or=97.8% of the infants were seropositive for antipertussis antibodies and the 7 pneumococcal serotypes. Predefined criteria for noninferiority between groups were reached for all antigens.

Conclusions: Two doses of RIX4414 coadministered with routine infant vaccines as recommended in the United States (DTaP-HBV-IPV, PCV7, and Hib) did not impair the immune response to any of the coadministered antigens.