Researchers at the University of Cambridge and its spinout DIOSynVax say an experimental mRNA vaccine protected mice and ferrets against diverse H5Nx bird flu viruses, testing a strategy designed to cover multiple viral groups.
Cambridge said the candidate fully protected the mice and ferrets in the tests. The paper reported stronger protection than World Health Organization (WHO) candidate vaccine virus comparators against antigenically distinct H5N1 challenges involving virus strains separated by about 20 years of evolution. About 50% of animals given a comparator survived, Cambridge said; the study was published Nov. 5 in Cell Reports Medicine.
The researchers measured antibodies that neutralized hemagglutinin (HA) and inhibited neuraminidase (NA) activity across different viral clades, the paper said. DVX-panH5Nx combines computationally engineered HA, NA and M2 antigens, giving priority to N1 and N6 subtypes. Cambridge said the team used sequences from worldwide bird flu surveillance to design synthetic antigens with AI, screened a range in cells and chose the best candidate for animal testing.
The strategy addresses the fact that H5Nx viruses can change and exchange genetic material as they infect birds and mammals, while existing H5 vaccines typically rely on a single HA strain, the study said. Cambridge said preparedness has relied on storing vaccines for variants already identified and updating them as viruses change. The university presents wider coverage as a possible public-health benefit and says repeated reformulation adds costs for health services.
Earlier studies have reported H5Nx protection in chickens and broad immune responses from a separate H5 vaccine candidate. Professor Jonathan Heeney, who led the study, said, “It’s designed to anticipate viral evolution, rather than reacting to it.”
The findings remain preclinical and do not show whether the vaccine protects people or against bird flu strains that have not yet emerged. Cambridge says human clinical trials are the next step, but it did not announce a start date.
