According to a study published by the Public Library of Science, the
vaccine, engineered by Novavax Inc., produced a strong immune response in mice
and protected them from death following infection with the H5N1 virus. The
vaccine is being tested in humans in an early-phase clinical trial.
“While worldwide avian flu control efforts have been mostly successful,
avian flu, like seasonal influenza, mutates year to year, creating new subtypes
and strains that could easily and quickly spread among humans,†said Ted M.
Ross, Ph.D., lead author of the study and assistant professor, Center for
Vaccine Research, University of Pittsburgh.
Safe alternative for human vaccine
The vaccine uses virus-like
particles (VLPs) that are recognised by the immune system as a
real virus but lacks genetic information to reproduce, making it a potentially
safer alternative for a human vaccine. Given the evolving nature of H5N1, the
vaccine was engineered to encode genes for three influenza viral proteins to
offer enhanced protection against possible new strains of the virus.
Mice immunised twice with the vaccine developed protective antibodies
against H5N1 and were protected from disease and death when directly exposed to
the virus. The researchers also compared modes of vaccine administration by
delivering the vaccine to the muscle or the nose. Both methods were effective;
however, mice injected with the vaccine through the muscle developed more
antibodies in the blood, while mice that received the nasal administration had
more antibodies in their lungs.
“VLPs may be advantageous over other vaccine strategies because they are
easy to develop, produce and manufacture,†said Ross. “Using recombinant
technologies, a vaccine effective against the current circulating strain of
virus could be manufactured within 12 weeks, making it a cost-effective
counter-measure to the threat of an avian influenza pandemic.â€
Related links:
