Immunogenicity of varying dosages of 7-valent pneumococcal polysaccharide-protein conjugate vaccine in seniors previously vaccinated with 23-valent pneumococcal polysaccharide vaccine.
Jackson LA,
Neuzil KM,
Nahm MH,
Whitney CG,
Yu O,
Nelson JC,
Starkovich PT,
Dunstan M,
Carste B,
Shay DK,
Baggs J,
Carlone GM.
Group Health Center for Health Studies, 1730 Minor Ave, Ste 1600, Seattle, WA 98101, USA. Jackson.L@ghc.org
In this dose-ranging study 220 seniors who had received the 23-valent pneumococcal polysaccharide (PnPS) vaccine at least 5 years prior to enrollment were assigned to receive one of four volumes (0.1, 0.5, 1 or 2 ml) of 7-valent pneumococcal conjugate (PnC) vaccine or a 0.5 ml dose of 23-valent PnPS vaccine. All participants received a reduced challenge dose of 0.1 ml of PnPS vaccine 1 year after enrollment. There was evidence of a dose response to PnC vaccine and antibody levels in the 1 ml PnC group tended to be significantly higher than in the PnPS group. A booster response to the challenge vaccination was not observed. Administration of a 1 ml dose of PnC vaccine is more immunogenic than 0.5 ml of PnPS vaccine in elderly adults previously vaccinated with PnPS vaccine.
PMID: 17391816 [PubMed - indexed for MEDLINE]