Polysaccharide conjugate vaccine against pneumococcal pneumonia in adults.

BACKGROUND: Pneumococcal polysaccharide conjugate vaccines prevent pneumococcal disease in infants, but their efficacy against pneumococcal community-acquired pneumonia in adults 65 years of age or older is unknown. METHODS: In a randomized, double-blind, placebo-controlled trial involving 84,496 adults 65 years of age or older, we evaluated the efficacy of 13-valent polysaccharide conjugate vaccine (PCV13) in preventing first episodes of vaccine-type strains of pneumococcal community-acquired pneumonia, nonbacteremic and noninvasive pneumococcal community-acquired pneumonia, and invasive pneumococcal disease. Standard laboratory methods and a serotype-specific urinary antigen detection assay were used to identify community-acquired pneumonia and invasive pneumococcal disease. RESULTS: In the per-protocol analysis of first episodes of infections due to vaccine-type strains, community-acquired pneumonia occurred in 49 persons in the PCV13 group and 90 persons in the placebo group (vaccine efficacy, 45.6%; 95.2% confidence interval [CI], 21.8 to 62.5), nonbacteremic and noninvasive community-acquired pneumonia occurred in 33 persons in the PCV13 group and 60 persons in the placebo group (vaccine efficacy, 45.0%; 95.2% CI, 14.2 to 65.3), and invasive pneumococcal disease occurred in 7 persons in the PCV13 group and 28 persons in the placebo group (vaccine efficacy, 75.0%; 95% CI, 41.4 to 90.8). Efficacy persisted throughout the trial (mean follow-up, 3.97 years). In the modified intention-to-treat analysis, similar efficacy was observed (vaccine efficacy, 37.7%, 41.1%, and 75.8%, respectively), and community-acquired pneumonia occurred in 747 persons in the PCV13 group and 787 persons in placebo group (vaccine efficacy, 5.1%; 95% CI, -5.1 to 14.2). Numbers of serious adverse events and deaths were similar in the two groups, but there were more local reactions in the PCV13 group. CONCLUSIONS: Among older adults, PCV13 was effective in preventing vaccine-type pneumococcal, bacteremic, and nonbacteremic community-acquired pneumonia and vaccine-type invasive pneumococcal disease but not in preventing community-acquired pneumonia from any cause. (Funded by Pfizer; CAPITA ClinicalTrials.gov number NCT00744263.).

A phase 3, randomized, double-blind trial comparing the safety and immunogenicity of the 7-valent and 13-valent pneumococcal conjugate vaccines, given with routine pediatric vaccinations, in healthy infants in Brazil.

BACKGROUND: The inclusion of 7-valent pneumococcal conjugate vaccine (PCV7) into national immunization programs in many countries has significantly decreased the incidence of disease caused by Streptococcus pneumoniae. However, a substantial portion of disease remained and, in some areas, there has been an increase in disease produced by serotypes not included in PCV7. A 13-valent pneumococcal conjugate vaccine (PCV13) was studied in healthy Brazilian infants in a phase 3, double-blind, randomized study. METHODS: Infants were randomized to receive either PCV7 or PCV13 at 2, 4, 6, (doses 1-3), and 12 (toddler dose) months of age, along with routine pediatric vaccinations (diphtheria, tetanus, whole-cell pertussis, and Haemophilus influenzae type b vaccine). Pneumococcal anticapsular polysaccharide-binding immunoglobulin G (IgG) responses and antibody responses to pertussis antigens were measured 1 month after both dose 3 of the infant series and the toddler dose. Safety and tolerability were also assessed. RESULTS: The proportion of subjects achieving a serotype-specific IgG concentration ≥0.35µg/mL measured 1 month after the infant series was comparable in the PCV13 (≥94.2%) and PCV7 (≥93.0%) groups for the 7 serotypes common to both vaccines. The percentage of responders for the 6 additional serotypes ranged from 87.1 to 100% for PCV13. The percentage of responders varied across the pertussis antigens studied, but was not different in PCV13 and PCV7 recipients. Overall, the safety profile of PCV13 was comparable with that of PCV7. CONCLUSIONS: PCV13 was comparable to PCV7 in safety and tolerability, elicited comparable immune responses to the common serotypes, and did not interfere with immune responses to concomitantly administered whole-cell pertussis vaccine. The robust immunogenicity exhibited by PCV13 for the additional serotypes suggests that it could provide significant protection against these serotypes.