Phase III Study Shows Prevenar 13 Is Immunogenic In Young Children Previously Vaccinated With Prevenar
According to results from a Phase III safety and immunogenicity study presented today, Prevenar 13* (Pneumococcal polysaccharide conjugate vaccine, [13-valent, adsorbed]) was shown to be immunogenic and generally well tolerated in healthy young children who had received at least three prior doses of Prevenar* (Pneumococcal Saccharide Conjugated Vaccine, Adsorbed). These data were presented today at the 7th International Symposium on Pneumococci and Pneumococcal Diseases (ISPPD) in Tel Aviv, Israel.
Prevenar 13 includes the seven serotypes (4, 6B, 9V, 14, 18C, 19F, and 23F) in Prevenar plus six additional serotypes (1, 3, 5, 6A, 7F, and 19A). Together, these 13 serotypes represent the most prevalent invasive disease-causing strains in young children worldwide.
“Prevenar has significantly reduced the incidence of invasive pneumococcal disease in young children in areas where it is routinely used. The data from this Phase III study showed that children up to 5 years of age previously vaccinated with Prevenar had an increased immune response against all 13 serotypes included in Prevenar 13,” says Robert W. Frenck, Jr., M.D., the study’s coordinating investigator and professor of pediatrics, Cincinnati Children's Hospital Medical Center.
Also presented at this meeting were data comparing immunogenicity and functional antibody responses in young children who were administered Prevenar and Prevenar 13. It has been suggested that pneumococcal conjugate vaccines that include serotypes 6B and 19F may provide some cross protection against invasive disease caused by 6A and 19A. The data presented suggest that the immunogenicity and functional antibody responses induced by Prevenar 13 for serotypes 6A and 19A were greater than the responses elicited by Prevenar. These results are believed to be attributable to the inclusion of these two serotypes in Prevenar 13.
“These data further suggest the importance of providing direct coverage against the 13 most common pneumococcal disease-causing serotypes worldwide,” says Emilio Emini, Ph.D., chief scientific officer, Vaccine Research, Pfizer Inc. “Notably, serotypes 6A and 19A, which are included in Prevenar 13, are prevalent in many regions of the world.”