Quadrivalent vs. Trivalent Flu Vaccines: Comparing Responses to B Strains
Geoffrey Gorse, MD, professor of internal medicine in the division of infectious diseases at Saint Louis University, and colleagues conducted a randomized, double-blind, multicenter trial evaluating the safety and immunogenicity of an intradermal quadrivalent split-virion influenza vaccine (IIV4-ID), which contains both lineages of the B strain. The 3,355 participants (between 18–64 years odd age) in the U.S. during the 2012–2013 influenza season were randomized to receive IIV4-ID, intradermal (ID), trivalent split-virion influenza vaccine (IIV3-ID), or an investigational IIV3-ID containing an alternate B-lineage strain. Hemagglutination inhibition antibody titers were evaluated in two-thirds of the study participants prior to vaccination and 28 days post-vaccination.
Antibody responses to IIV4-D were statistically non-inferior to the response to the IIV3-ID vaccines containing the matched strains. However, antibody responses to IIV4-ID were statistically superior to the responses to IIV3-ID lacking the corresponding B strain post-vaccination for both B strains. The IIV4-D did not weaken immunogenicity to the A lineage strains in the vaccine.
The quadrivalent influenza vaccine could be an important means of providing additional protection against influenza based on these results, the authors note.
For more information visit SLU.edu.