Comparability of Titers of Antibodies against Seasonal Influenza Virus Strains as Determined by Hemagglutination Inhibition and Microneutralization Assays.

We compared titers of antibodies against A/H1N1, A/H3N2, and B influenza virus strains collected pre- and postvaccination using hemagglutination inhibition (HI) and microneutralization (MN) assays and data from two vaccine trials: study 1, performed with a cell-grown trivalent influenza vaccine (TIVc) using cell-grown target virus in both assays, and study 2, performed with an egg-grown adjuvanted quadrivalent influenza vaccine (aQIVe) using egg-grown target virus. The relationships between HI- and MN-derived log-transformed titers were examined using different statistical techniques. Deming regression analyses showed point estimates for slopes generally close to 1 across studies and strains.

A phase 1, randomized, observer blind, antigen and adjuvant dosage finding clinical trial to evaluate the safety and immunogenicity of an adjuvanted, trivalent subunit influenza vaccine in adults ≥ 65 years of age.

Objective: To assess the safety and immunogenicity of the MF59®-adjuvanted trivalent influenza vaccine (aTIV; Fluad®) compared with modified aTIV formulations.

Methods: A total of 196 subjects ≥ 65 years were randomized to receive7different formulations of vaccine containing a range of adjuvant and antigen dosesby single injection, or divided into two injections at a single time point. The primary study objective was to compare the serologic response of different formulations of aTIV containing increased amounts of adjuvant and antigen21 days after vaccination.