Clinical stage biopharmaceutical company CureVac and the German Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute (FLI), have announced that messenger (m)RNA prophylactic vaccines based on CureVac’s RNActive platform exhibited immunogenicity and protection against influenza virus infection.
In vivo data published by CureVac and FLI revealed that mRNA vaccines stimulated balanced, long-lived and protective immunity to influenza A virus infections in different animal models.
RNActive vaccine technology allows fast production of RNActive vaccines, which are stable at high temperatures, and can be supplied for various virus strains in response to pandemic situation.
CureVac CEO Dr Ingmar Hoerr said the findings confirm the capacity of RNActive vaccines in preventing infectious diseases.
"The synthetic nature of our RNActive vaccines reduces production time dramatically and allows for sequence-matched vaccines that can be produced quickly and reliably in a scalable process.
"Additionally, our vaccines can be stored at room temperature, thereby avoiding the cold-chain in contrast to all other vaccines on the market and making worldwide distribution of our vaccines logistically and financially attractive," Hoerr said.
According to the data, the mRNA vaccine encoding full-length hemagglutinin (HA) of the influenza A/PuertoRico/8/1934 (PR8HA) strain was immunogenic and provoked balanced B and T-cell responses in mice.
Sequence-matched, HA-specific vaccines targeting additional influenza A virus strains also demonstrated protection against lethal infections.
Complete protection was achieved upon single-dose immunisation against influenza A/PR8 with a multi-component HA and NA mRNA vaccine.
In addition, vaccination with PR8 nucleoprotein (NP) mRNA resulted in protection against homologous PR8 (H1N1) or heterologous MB1 (H5N1) virus.
mRNA vaccines that provided heterologous protection offered immunogenicity in ferrets, various animal models opted in influenza research and pigs, compared to a licensed trivalent vaccine of equivalent specificity.
Image: Transmission electron micrograph of influenza A virus. Photo: Courtesy of CDC/ Dr Erskine Palmer.