Safety and immunogenicity of 13-valent pneumococcal conjugate vaccine in healthy infants and toddlers receiving routine vaccinations in Spain

AIMS: To compare the immune response of selected antigens included in routine childhood vaccines when administered concomitantly with PCV13 or 7-valent pneumocccal conjugate vaccines (PCV7), and to assess the safety and immunogenicity of PCV13 in infants and toddlers. METHODS: Healthy infants were randomized to receive PCV13 (n=315) or PCV7 (n=304) with DTaP-Hepatitis B-IPV-Hib at ages 2, 4, and 6 months and a meningococcal C vaccine (MnCC) at ages 2 and 4 months. Antibody response to selected antigens in both groups was assessed 1 month after doses 2 and 3 and 1 month after the toddler dose. Local and systemic events were reported for 4 days following vaccination. RESULTS: For all concomitant antigens, noninferiority was established at >-10% (lower limit of 95% CI for the difference in proportions between PCV13 and PCV7). Infant immune responses induced by DTaP, polio and MnCC antigens administered with PCV13 were noninferior to those observed with administration of PCV7. After infant dose 3 of PCV13, ≥97% of infants achieved pneumococcal anticapsular IgG concentrations ≥0.35 µg/mL (WHO antibody threshold for comparative assessment of pneumococcal vaccines) for all serotypes except serotypes 3 (90.3%) and 23F (94.6%). Following the toddler dose of PCV13, >98.7% achieved pneumococcal IgG antibody concentrations ≥0.35 µg/mL for all serotypes except serotype 3 (92.2%). Local and systemic reactions were similar between groups. CONCLUSIONS: Immune responses for selected concomitantly administered vaccine antigens were comparable in both groups PCV13 has an acceptable safety profile and elicits a likely effective antipneumococcal immune response in infants and toddlers.