CSL's (ASX:CSL) CSL Seqirus unit disclosed publication of pivotal phase 3 study results for its MF59-adjuvanted cell-based higher-dose quadrivalent influenza vaccine (aQIVc) for influenza prevention in older adults in The Lancet Infectious Diseases, according to a Friday statement.

The phase 3 randomized immunogenicity and safety study enrolled 7,699 adults aged 50 and older across eight countries and compared aQIVc with two enhanced influenza vaccines, demonstrating superiority versus the adjuvanted egg-based influenza vaccine comparator across all four influenza strains and age groups, and non-inferiority versus a recombinant influenza vaccine for three out of four strains in the 50-plus age group and four out of four strains in those aged 65 and older, the company said.

The study also demonstrated immune responses that persisted throughout the influenza season and a well-tolerated safety profile, with most reactions mild or moderate and resolving within three days, CSL added.

The study authors concluded that the findings support further evaluation of the vaccine and provide evidence for national immunization advisory groups considering enhanced influenza vaccination strategies for older adults, per the statement.

The company's shares fell almost 1% in recent Friday trade.