LB-7. Immunogenicity and Safety of a 13-Valent Pneumococcal Conjugate Vaccine Coadministered with a Quadrivalent Influenza Vaccine in Adults 50 Years and Older Previously Vaccinated with 23-Valent Pneumococcal Polysaccharide Vaccine
Session: Oral Abstract Session: Late Breaker Oral Abstract Session
Saturday, October 10, 2015: 11:30 AM
Room: 7--AB
Background: This phase 4, randomized, placebo-controlled, double-blind, study evaluated immune responses after coadministration of 13-valent pneumococcal conjugate vaccine (PCV13) and a quadrivalent inactivated influenza vaccine (QIV) in adults aged ≥50 years previously immunized with 23-valent pneumococcal polysaccharide (PPSV23). Methods: Subjects received PCV13+QIV then placebo 1 month later (group 1) or placebo+QIV then PCV13 1 month later (group 2). Opsonophagocytic activity (OPA) geometric mean titers (GMTs) and hemagglunation inhibition assay (HAI) GMTs for 13 pneumococcal serotypes and 4 influenza strains respectively, were assessed before and 1 month after vaccination. The prespecified noninferiority criterion was 2-fold (0.5 lower limit of 95% CI for GMT ratios). Adverse events (AEs) and serious AEs (SAEs) were assessed. Results: The evaluable immunogenicity population in groups 1 and 2 comprised 421 and 425 subjects respectively (mean age, years [±SD], 67.0 [±9.08] and 66.4 [±8.84]); >93% of subjects had received ≥1 PPSV23 dose. The noninferiority criterion was met for OPA GMTs for all 13 pneumococcal serotypes (Table 1). In most cases, GMT point estimates were lower when PCV13 was coadministered, with significantly lower GMTs (upper limit of the 95% CI <1 on the GMT ratio) for serotypes 3, 4, 6A, and 14. Baseline HAI GMTs were similar between groups and rose postvaccination. Noninferiority was met for all 4 QIV strains (Table 2). Seroconversion rates (4-fold rise in pre- vs postvaccination HAI titer) were low but similar between groups (range, 21.3%–31.6%). A post hoc analysis showed similar percentages of subjects achieving HAI titers ≥1:40 in groups 1 and 2 respectively, (90.6% and 89.3% for A/H1N1, 98.4% and 96.5% for A/H3N2, 49.2% and 46.5% for B/Brisbane, and 65.8% and 63.3% for B/Massachusetts). Responses for B strains were low in both groups. SAEs reported were consistent with conditions expected in this population; none were vaccine-related.     Conclusion: Immune responses to PCV13 and QIV were noninferior to PCV13 given alone, but associated with lower PCV13 responses that were significantly lower for 4 serotypes. Concomitant PCV13 and QIV administration yielded similar HAI responses compared to QIV alone, and was well tolerated.
Roger Baxter, MD, FIDSA1, H. Jackson Downey, MD2, Scott D. Patterson, PhD3, Vani Sundaraiyer, PhD4, Wendy Watson, MD3, Keri Clarke, MD5, William C. Gruber, MD, FIDSA6, Daniel A. Scott, MD6, Allison Thompson, MD, FAAP6 and Beate Schmoele-Thoma, MD7, (1)Kaiser Permanente Vaccine Study Center, Oakland, CA, (2)Jacksonville Center for Clinical Research, Jacksonville, FL, (3)Pfizer Vaccine Research, Collegeville, PA, (4)inVentiv Health Clinical, LLC, Princeton, NJ, (5)Pfizer Inc, Walton Oaks, United Kingdom, (6)Pfizer Vaccine Research, Pearl River, NY, (7)Pfizer Pharma GmbH, Berlin, Germany

Disclosures:

R. Baxter, Pfizer: Grant Investigator , Research grant
Merck: Grant Investigator , Research grant
Sanofi-Pasteur: Grant Investigator , Research grant
GSK: Grant Investigator , Research grant
Novartis: Grant Investigator , Research grant
MedImmune: Grant Investigator , Research grant

H. J. Downey, JCCR Westside: Investigator , Research grant

S. D. Patterson, Pfizer: Employee , Salary

V. Sundaraiyer, Pfizer: My company is contracted by Pfizer , Salary

W. Watson, Pfizer: Employee and Shareholder , Salary

K. Clarke, Pfizer: Employee , Salary

W. C. Gruber, Pfizer: Employee and Shareholder , Salary and Stock and stock options

D. A. Scott, Pfizer: Employee , Salary and Stock and stock options

A. Thompson, Pfizer Inc: Employee , Salary and Stock and stock options

B. Schmoele-Thoma, Pfizer: Employee and Shareholder , Salary and Stock and stock options

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