OVX836 is a universal influenza A vaccine which appears to be safe and has previously shown a preliminary signal of protection against influenza symptoms.
Now, in a study published in The Lancet Infectious Diseases, researchers sought to explore the safety and potential efficacy of higher doses of OVX836. This is a recombinant protein-based vaccine which targets the highly conserved influenza nucleoprotein (NP) and therefore potentially confers broad-spectrum protection against influenza.
Influenza viruses are associated with over five million hospitalisations every year across the world. Moreover, anti-viral agents such as oseltamivir do not appear to reduce influenza-related hospitalisations, highlighting the need for effective vaccinations.
OVX836 safety and efficacy
In the trial, a total of 137 healthy adults aged 18-55 years were randomly assigned to receive one single intramuscular administration of OVX836 influenza vaccine at three doses (180 μg, 300 μg or 480 μg) or placebo.
OVX836 had a favourable safety profile up to 480 μg without reaching the maximum tolerated dose and showed a good safety profile at all doses with only mild local and systemic reactogenicity.
Seven days after vaccination, there were no significant differences observed between the doses. Dose-dependent and poly-functional nucleoprotein-specific CD4 T-cell responses were observed, and CD8 T-cell responses were elicited at 300 μg and 480 μg.
In a planned further exploratory endpoint, the study also evaluated the protection level of the vaccine against RT-PCR-confirmed influenza A. During the influenza season, there were four RT-PCR-confirmed influenza A cases in the placebo group but only two in the OVX836 group. This resulted in an observed level of protection of 84% (95% CI 17–97) for OVX836 at the time of maximum exposure to influenza.
Study lead investigator Dr Paul Griffin said: ‘By combining OVX836 with the current standard of care, we expect to bring much-needed and critical additional protection against seasonal influenza, especially for high-risk populations, including the elderly.‘
Alexandre Le Vert, CEO and co-founder of the vaccine manufacturer Osivax, added: ‘The initiation of our multicenter Phase 2a trial marks an important milestone for Osivax as we continue optimising the development of OVX836 in combination with conventional influenza vaccines within a larger and more diverse population. We are eager to build upon the promising initial data from our previous study in an effort to provide improved and broad-spectrum protection, especially for at-risk populations.‘