Safety, immunogenicity, and efficacy of an alphavirus replicon-based swine influenza virus hemagglutinin vaccine

A single-cycle, propagation-defective replicon particle (RP) vaccine expressing a swine influenza virus hemagglutinin (HA) gene was constructed and evaluated in several different animal studies. Studies done in both the intended host (pigs) and non-host (mice) species demonstrated that the RP vaccine is not shed or spread by vaccinated animals to comingled cohorts, nor does it revert to virulence following vaccination. In addition, vaccinated pigs develop both specific humoral and IFN-γ immune responses, and young pigs are protected against homologous influenza virus challenge.

► The alphavirus replicon system was used to construct a swine influenza virus vaccine. ► Safety testing was conducted in the intended host (pigs) and non-host (mice) species. ► Immunogenicity and efficacy studies were performed in pigs of various ages. ► The H3 RP vaccine is not shed or spread, nor does it revert to virulence. ► The H3 RP vaccine elicits specific immune responses and is efficacious in pigs.