A randomized, double-blind noninferiority study of quadrivalent live attenuated influenza vaccine in adults |
| |
Authors: | Block Stan L Yi Tingting Sheldon Eric Dubovsky Filip Falloon Judith |
| |
Institution: | a Kentucky Pediatric and Adult Research, 201 South 5th Street, Bardstown, KY 40004-1142, USA b MedImmune, LLC, One MedImmune Way, Gaithersburg, MD 20878, USA c Miami Research Associates, 6141 Sunset Drive Suite 501, Miami, FL 33143, USA |
| |
Abstract: | BackgroundTrivalent seasonal influenza vaccines contain 2 A strains and 1 B strain. B strains of 2 antigenically distinct lineages, Yamagata and Victoria, have been co-circulating annually, and the B strain included in vaccines often has not been a lineage match to the major circulating strain. Thus, a vaccine containing B strains from both lineages could broaden protection against influenza. Quadrivalent live attenuated influenza vaccine (Q/LAIV) is an investigational 4-strain formulation of LAIV that contains 2 A strains, A/H1N1 and A/H3N2, and 2 B strains, 1 from each lineage.MethodsA randomized, double-blind, active-controlled study of Q/LAIV was conducted in 1800 adults aged 18-49 years to compare the immunogenicity and safety of Q/LAIV to trivalent LAIV (T/LAIV). Subjects were randomized 4:1:1 to receive an intranasal dose of Q/LAIV (n = 1200) or 1 of 2 matching T/LAIV vaccines, each containing 1 of the B strains included in Q/LAIV (n = 600 total). The primary endpoint was the comparison of the post-vaccination strain-specific geometric mean titers (GMT) of hemagglutination inhibition antibody in Q/LAIV recipients to those in T/LAIV recipients, with immunologic noninferiority of Q/LAIV to be demonstrated if the upper bound of the 2-sided 95% confidence interval (CI) for the ratio of the GMTs T/LAIV divided by Q/LAIV] was ≤1.5 for all strains.Results and ConclusionQ/LAIV met the criteria for noninferiority: the ratios of the GMTs for the A/H1N1, A/H3N2, B/Yamagata, and B/Victoria strains were 1.09 (95% CI, 1.01-1.18), 1.05 (95% CI, 0.96-1.14), 1.10 (95% CI, 0.97-1.25), and 0.92 (95% CI, 0.82-1.03), respectively. Solicited symptoms and adverse events were similar in the Q/LAIV and T/LAIV arms. Q/LAIV may confer increased protection against influenza by targeting B strains from both lineages. |
| |
Keywords: | AE adverse event CI confidence interval FFU fluorescent focus units GMFR geometric mean fold rise from baseline GMT geometric mean titer HAI hemagglutination inhibition MedDRA Medical Dictionary for Regulatory Activities Q/LAIV quadrivalent live attenuated influenza vaccine SAE serious adverse event T/LAIV trivalent live attenuated influenza vaccine US United States of America |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|