Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in adults
70 years of age and older previously vaccinated with 23-valent pneumococcal
polysaccharide vaccine.
Author(s): Jackson LA(1), Gurtman A, Rice K, Pauksens K, Greenberg RN, Jones TR, Scott DA,
Emini EA, Gruber WC, Schmoele-Thoma B.
Affiliation(s): Author information:
(1)The Group Health Research Institute, Group Health, Seattle, WA, USA.
jackson.l@ghc.org
Publication date & source: 2013, Vaccine. , 31(35):3585-93
BACKGROUND: The currently recommended single dose of the 23-valent pneumococcal
free polysaccharide vaccine (PPSV23) for adults 65 years of age and older does
not provide extended protection into older age. This reflects a significant unmet
medical need for alternative strategies to protect older adults against
pneumococcal infection, which may be met by the 13-valent polysaccharide
conjugate vaccine (PCV13).
METHODS: We performed a randomized, modified double-blind trial in 936 adults
aged 70 years and older who had previously received PPSV23 at least 5 years
before study entry and were now vaccinated with PCV13 or PPSV23. At 1 year after
enrollment, all subjects received a follow-on dose of PCV13. Anti-pneumococcal
opsonophagocytic activity (OPA) titers were measured before and at 1 month after
each vaccination.
RESULTS: Following the enrollment vaccination, OPA titers were significantly
greater in the PCV13 group compared to the PPSV23 group for 10 of the 12
serotypes common to both vaccines and to serotype 6A which is unique to PCV13.
Responses were noninferior for the other 2 common serotypes. Responses to PCV13
given at 1 year were generally lower in the group that received PPSV23 at
enrollment.
CONCLUSION: In adults aged 70 years and older previously vaccinated with PPSV23,
PCV13 was significantly more immunogenic than PPSV23 for most of the common
serotypes and for serotype 6A. The OPA responses after a follow-on dose of PCV13
one year later indicate that a prior dose of PPSV23, but not PCV13, diminishes
the response to the subsequent administration of PCV13.
|