Immunogenicity and Safety of the 13-Valent Pneumococcal Conjugate Vaccine versus the 23-Valent Polysaccharide Vaccine in Unvaccinated HIV-Infected Adults: A Pilot, Prospective Controlled Study.
OBJECTIVE
Definition of the optimal pneumococcal vaccine strategy in HIV-infected adults is still under evaluation. We aimed to compare immunogenicity and safety of the 13-valent pneumococcal conjugate vaccine (PCV13) versus the 23-valent polysaccharide vaccine (PPSV23) in HIV-infected adults.


METHODS
We performed a pilot, prospective controlled study enrolling HIV-infected pneumococcal vaccine-naïve outpatients, aged 18-65 years with CD4 counts ≥200 cells/μL. Eligible subjects were recruited into two parallel groups: group 1 (n = 50) received two doses of PCV13 eight weeks apart, and group 2 (n = 50) received one dose of PPSV23, as part of their standard of care. Anti-pneumococcal capsular polysaccharide immunoglobulin G concentrations were quantified by ELISA at baseline, 8, 24 and 48 weeks. Clinical and viro-immunological follow-up was performed at the same time points. Unvaccinated, age-matched HIV-negative adults (n = 100) were also enrolled as baseline controls.


RESULTS
Pre-vaccination specific IgG titers for each pneumococcal antigen did not differ between study groups but they were constantly lower than those from the HIV-negative controls. After immunization, significant increases in IgG titers were observed in both study groups at each time point compared to baseline, but response to serotype 3 was blunted in group 1. Antibody titers for each antigen did not differ between study groups at week 48. Overall, the proportion of subjects achieving seroprotection and seroconversion to all serotypes was comparable between groups. A marked decrease in IgG levels over time was observed with both vaccines. No relevant adverse reactions were reported in either group.


CONCLUSIONS
In this population with favorable immune profile, no relevant differences were observed in immunogenicity between PCV13 and PPSV23. Both vaccines were safe and well tolerated.


BACKGROUND
ClinicalTrials.gov NCT02123433.
Institute of Clinical Infectious Diseases, Catholic University of the Sacred Heart, Largo Agostino Gemelli 8, Rome, Italy.
Francesca
F
Lombardi
Institute of Clinical Infectious Diseases, Catholic University of the Sacred Heart, Largo Agostino Gemelli 8, Rome, Italy.
Simone
S
Belmonti
Institute of Clinical Infectious Diseases, Catholic University of the Sacred Heart, Largo Agostino Gemelli 8, Rome, Italy.|Division of Infectious Diseases, Department of Internal Medicine, San Gerardo Hospital, University of Milano-Bicocca, Monza, Italy.
Massimiliano
M
Fabbiani
Department of Medical Biotechnologies, University of Siena, Viale Bracci 16, Siena, Italy.
Matteo
M
Morandi
University Division of Infectious Diseases, Hospital Department of Specialized and Internal Medicine, Viale Bracci 16, Siena, Italy.
Barbara
B
Rossetti
Department of Medical Biotechnologies, University of Siena, Viale Bracci 16, Siena, Italy.
Giacinta
G
Tordini
Institute of Clinical Infectious Diseases, Catholic University of the Sacred Heart, Largo Agostino Gemelli 8, Rome, Italy.
Roberto
R
Cauda
Department of Medical Biotechnologies, University of Siena, Viale Bracci 16, Siena, Italy.|University Division of Infectious Diseases, Hospital Department of Specialized and Internal Medicine, Viale Bracci 16, Siena, Italy.
Andrea
A
De Luca
Institute of Clinical Infectious Diseases, Catholic University of the Sacred Heart, Largo Agostino Gemelli 8, Rome, Italy.
Simona
S
Di Giambenedetto
Department of Medical Biotechnologies, University of Siena, Viale Bracci 16, Siena, Italy.|University Division of Infectious Diseases, Hospital Department of Specialized and Internal Medicine, Viale Bracci 16, Siena, Italy.
Francesca
F
Montagnani
D000293:Adolescent; D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000276:immunology; D016001:Confidence Intervals; D005260:Female; D015658:HIV Infections / Q000517:prevention & control*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D008297:Male; D008875:Middle Aged; D022242:Pneumococcal Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D011446:Prospective Studies; D065288:Serogroup; D018074:Vaccines, Conjugate / Q000009:adverse effects / Q000627:therapeutic use*; D055815:Young Adult
C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate