Novavax, Inc.'s novel virus-like particle (VLP) vaccines have been shown to be effective in generating protection against pandemic influenza as well as cross protection against different strains of the virus in pre-clinical studies, according to data presented at the Phacilitate Vaccine Forum.
"These are the first live-virus challenge data we have presented," said Dr. Rick Bright, Novavax's Vice President of Global Influenza Programs. "These new data are exciting because not only do our VLP vaccines trigger a robust immune response, but we have shown that a single vaccine can protect against two different strains of pandemic influenza."
The studies involved two of Novavax's H5N1 influenza VLP vaccines - one targeting the Indonesia strain of pandemic flu, first identified in 2005, and another targeting the Viet Nam strain, identified in 2003.
Both mice and ferrets inoculated with the Indonesia VLP vaccine showed a robust immune response in the study. When challenged with both the Indonesia and Viet Nam strains, the animals were protected against both viruses.
The ferret is the most relevant animal model for influenza because ferrets exhibit similar clinical symptoms as humans and are naturally susceptible to most human influenza viruses, including H5N1. "Ferrets are the most predictive model used for evidence of immunogenicity of influenza vaccines for humans," Dr. Bright said.
In addition, Novavax has shown that mice inoculated with the Viet Nam strain of the company's VLP vaccine were protected from that strain as well as from the Indonesian strain of pandemic influenza.
"These new data give us more confidence as we prepare to enter human clinical trials with our pandemic vaccine later this year," Dr. Bright said. "We also are increasingly confident about our ability to generate similar results in our seasonal influenza vaccine program as it progresses in pre-clinical testing."
The challenge studies were conducted in collaboration with the University of Pittsburgh, and the data have been submitted for peer-review publication. In addition, the U.S. Centers for Disease Control and Prevention (CDC) will conduct live challenge studies using Novavax's VLP pandemic influenza vaccines.
"We expect the CDC to further confirm these new data before we enter the clinic this year," Dr. Bright said.