Conjugated heptavalent pneumococcal vaccine

OBJECTIVE: To review the immunogenicity, efficacy, and safety of the heptavalent conjugated pneumococcal vaccine (PCV7). DATA SOURCES: A MEDLINE search (1993-August 2001) of research limited to humans published in the English language was conducted. STUDY SELECTION: Findings from randomized, controlled, multicenter trials were reviewed. Literature regarding epidemiology, control, and treatment of invasive pneumococcal diseases in different populations and the Advisory Committee on Immunization Practices recommendations were also reviewed. DATA SYNTHESIS: PCV7 administered to infants aged 2, 4, and 6 months, with a booster dose at 12-15 months, has been shown to be immunogenic. It decreases the incidence of invasive pneumococcal disease; individual data on bacteremia and meningitis are unavailable. Findings from clinical trials showed that invasive pneumococcal disease caused by vaccine serotypes was reduced by 87%, 58%, and 62% for children <1 year, <2 years, and <5 years of age, respectively, after introduction of routine vaccine use. The overall incidence of acute otitis media did not decrease significantly. However, culture-confirmed episodes and episodes due to pneumococcal serotypes included in the vaccine were reduced. The vaccine was immunogenic in children with sickle cell disease, but its efficacy in preventing invasive pneumococcal diseases remains unclear. Although immunogenicity and efficacy trials are lacking, the vaccine is recommended for Alaskan Native or American Indian children between 24 and 59 months of age, and for children with underlying conditions such as HIV infection, AIDS, other immunocompromising conditions, and chronic illnesses. At the manufacturer's list price of $58/dose, PCV7 is not projected to be cost-effective after 4 doses. Postmarketing analysis evaluating immunogenicity and efficacy in the excluded population may favorably change this. CONCLUSIONS: Based on published efficacy and immunogenicity data, pharmacy formularies should include PCV7.