Long-term comparative immunogenicity of protein conjugate and free polysaccharide pneumococcal vaccines in chronic obstructive pulmonary disease.
BACKGROUND
Although the 23-valent pneumococcal polysaccharide vaccine (PPSV23) protects against invasive disease in young healthy persons, randomized controlled trials in chronic obstructive pulmonary disease (COPD) have demonstrated no benefit in the intention-to-treat population. We previously reported that the 7-valent diphtheria-conjugated pneumococcal polysaccharide vaccine (PCV7) is safe and induced greater serotype-specific immunoglobulin G (IgG) and functional antibody than did PPSV23 1 month after vaccination. We hypothesized that these advantages would persist at 1 and 2 years.


METHODS
One hundred eighty-one patients with moderate to severe COPD were randomized to receive PPSV23 (n = 90) or PCV7 (1.0 mL; n = 91). We measured IgG by enzyme-linked immunosorbent assay and assessed functional antibody activity by a standardized opsonophagocytosis assay, reported as a killing index (OPK). We determined differences in IgG and OPK between vaccine groups at 1 and 2 years.


RESULTS
Relative to PPSV23, PCV7 induced greater OPK at both 1 and 2 years for 6 of 7 serotypes (not 19F). This response was statistically greater for 5 of 7 serotypes at 1 year and 4 of 7 at 2 years. Comparable differences in IgG were observed but were less often statistically significant. Despite meeting Centers for Disease Control and Prevention criteria for PPSV23 administration, almost 50% of individuals had never been vaccinated. No differences in the frequency of acute exacerbations, pneumonia, or hospitalization were observed.


CONCLUSIONS
PCV7 induces a greater functional antibody response than PPSV23 in patients with COPD that persists for 2 years after vaccination. This superior functional response supports testing of conjugate vaccination in studies examining clinical end points.


BACKGROUND
NCT00457977.
Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA. mdransfield99@msn.com
Mark T
MT
Dransfield
Sarah
S
Harnden
Robert L
RL
Burton
Richard K
RK
Albert
William C
WC
Bailey
Richard
R
Casaburi
John
J
Connett
J Allen D
JA
Cooper
Gerard J
GJ
Criner
Jeffrey L
JL
Curtis
Meilan K
MK
Han
Barry
B
Make
Nathaniel
N
Marchetti
Fernando J
FJ
Martinez
Charlene
C
McEvoy
Moon H
MH
Nahm
Dennis E
DE
Niewoehner
Janos
J
Porszasz
John
J
Reilly
Paul D
PD
Scanlon
Steven M
SM
Scharf
Frank C
FC
Sciurba
George R
GR
Washko
Prescott G
PG
Woodruff
Stephen C
SC
Lazarus
D000368:Aged; D015331:Cohort Studies; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D010587:Phagocytosis / Q000276:immunology; D011008:Pneumococcal Infections / Q000276:immunology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D016016:Proportional Hazards Models; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000276:immunology* / Q000382:microbiology*
C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines