The study aims to compare the immunogenicity and safety of seasonal influenza vaccine RIBSP to commercial vaccination VAXIGRIP® in a phase II clinical trial on healthy volunteers aged up to 60 years. The trial included 150 participants divided into randomised 2:1 groups and given either the RIBSP vaccination or the comparator vaccination VAXIGRIP®. One dosage of either vaccination contained 15 g of hemagglutinin from each influenza virus strain approved by WHO for the Northern hemisphere’s flu season in 2016–2017. In 21 days, 80.0 percent of individuals had 4-fold seroconversions to A/H1N1, 65.0 percent to /H3N2, and 64.0 percent to B virus, according to an assessment of the vaccine’s immunogenic efficacy. The antibody titer increase factor in the RIBSP vaccine group was 13.4 for /H1N1, 5.2 for /H3N2, and 5.2 for B virus. The patients who received the RIBSP vaccine displayed an 88 percent seroprotection rate against /H1N1, a 75 percent seroprotection rate against /H3N2, and a 61 percent seroprotection rate against B virus. There were no significant adverse events reported during the vaccination safety evaluation.

The comparison vaccines, RIBSP and VAXIGRIP®, had comparable immunogenic activity. The RIBSP vaccine is safe and immunogenic for the aged, and it meets the worldwide CPMP/BWP/214/96 requirements.