Prevenar 13 protects older people

The European Commission recently approved the pneumococcal vaccine Prevenar 13 (13-valent polysaccharide conjugate vaccine; PCV13) to prevent pneumonia caused by Streptococcus pneumoniae in patients aged 18 years and older. The Joint Committee on Vaccination and Immunisation is reviewing the UK's adult pneumococcal immunisation programme.

Against this background, the CAPiTA study, funded by Pfizer, immunised 42,240 people aged 65 years or older with PCV13, while 42,256 received placebo. Mean follow-up was 3.97 years in each group, and 12.4% and 12.6% of the PCV13 and placebo groups discontinued.

Forty-nine people in the PCV13 group (0.12%) developed a first episode of community acquired pneumonia (CAP) caused by vaccine-type strains compared with 90 (0.21%) in the placebo arm. This suggests that the vaccine's efficacy is 45.6% against these strains. Thirty-three and 60 people (0.08% and 0.14%) in the PCV13 and placebo arms respectively developed a first episode of non-bacteraemic and non-invasive CAP caused by the vaccine-type strains, suggesting efficacy of 45%. A first episode of invasive pneumococcal disease occurred in 7 (0.02%) and 28 (0.07%) patients respectively, suggesting 75% efficacy against vaccine-type strains. Serious adverse events and deaths were similar in the two groups. However, there were more local reactions in the PCV13 group.