Pneumococcal Conjugate Vaccine 13 (Prevnar13®) in Children Who Are Solid Organ Transplant Recipients (SOT)

The purpose of this study is to determine if a booster dose of 13-valent pneumococcal conjugate vaccine (PCV13) is safe and results in a measurable and durable immunologic response against pneumococcal subtypes present in the vaccine in solid organ transplant recipient (SOT) children. Pneumococcal infections are amongst the most common infections seen in immunocompromised children. Infection by Streptococcus pneumoniae is one of the most frequently observed infection in immunocompromised children. Pneumococcal polysaccharide vaccines (PPV) have been licensed in the U.S. for over 40 years. In contrast, pneumococcal conjugate vaccines are immunogenic and efficacious in normal infants and children, and offer hope of reducing pneumococcal infections in immunocompromised children. However, conjugate pneumococcal vaccine can only protect against a limited number of the 90 pneumococcal serotypes. It is reasonable to anticipate that the introduction of PCV13 may help reduce the chances of severely immunocompromised children getting pneumococcal infections. Many of these children have been previously immunized with a full series of a 7-valent pneumococcal conjugate vaccine. These children will benefit from an additional dose of the new 13-valent vaccine. The degree to which SOT-recipient children are protected by prior immunizations and are responsive to new immunizations is still largely undefined. This study aims to expand the knowledge regarding the safety and immunogenicity of PCV13 immunization in this growing and vulnerable population.