An article published in the December 8, 2011 issue of the New England Journal of Medicine describes a proof of principle study in which an intranasal dry powder vaccine significantly reduced Norwalk virus gastroenteritis and infection in study participants innoculated with Norwalk virus. LigoCyte Pharmaceuticals created the vaccine from virus-like particles since norovirus cannot be grown under laboratory conditions.
Researchers from Baylor College of Medicine were part of a consortium that dosed 90 participants with the dry powder vaccine or a placebo inactive vaccine. After three weeks, 84 of the participants were innoculated with the virus. Just over a third of the participants who received the active vaccine developed gastroenteritis compared to slightly more than two thirds of those who received the placebo. Vaccine recipients who became ill experienced less severe symptoms than did the unvaccinated participants who became ill. Although only 37% of the participants vaccinated developed symptoms, 61% became infected compared to approximately 80% who got the placebo.
Mary Estes, Professor of molecular virology and microbiology at Baylor commented, “these studies show for the first time that a non-replicating vaccine given intranasally can induce protection against a gastrointestinal pathogen. We had been told this couldn’t be done.”
LigoCyte CEO Donald Beeman added, “We look forward to continued development of our VLP (virus-like particle)-based norovirus vaccine candidates including additional clinical studies of our bivalent intramuscular vaccine.” The intramuscular vaccine is the company’s lead product, and the intranasal formulation is an alternate candidate.
Read the abstract.
Read a Baylor College of Medicine press release.
