Immunogenicity and safety of pneumococcal 7-valent conjugate vaccine (diphtheria CRM197 protein conjugate; Prevenar™) in Korean infants: Differences that are found in Asian children

This study was conducted to determine the immunogenicity and safety of a 7-valent CRM197 protein conjugated pneumococcal vaccine (PCV7) in Korean infants immunized at 2, 4 and 6 months. A total of 202 infants were enrolled and 146 and 141 infants were, respectively, included in post-2nd dose and post-3rd dose immunogenicity evaluations conducted on a per protocol basis. After two and three PCV7 vaccinations, 63.0–98.0 and 97.2–100% of infants achieved an antibody level of ≥0.35 μg/mL, respectively, with a lowest against serotype 6B. No vaccination-related serious adverse reactions were observed. Thus, PCV7 appears safe and highly immunogenic in Korean infants, and adopting two doses for a primary series could be a feasible option for facilitating vaccine coverage rate.