New nasal influenza vaccine elicits robust immunity in ferrets

Washington, October 29 : A novel influenza vaccine, which is delivered nasally, has been found to trigger robust immunity in ferrets, say researchers.

Experts at NanoBio Corporation have revealed that the immune responses elicited by the new vaccine were more than 20 times higher than those generated by two injections of the currently approved vaccines.

The researchers also revealed that their intranasal vaccine used only half the standard antigen dose to produce that effect.

According to them, their nasal vaccines exert adjuvant activity without the need for pro-inflammatory materials, toxins or cytokines.

"Our nanoemulsion-based intranasal vaccine adjuvant system represents a paradigm shift in vaccinology. It can be used to safely deliver multiple antigen types directly into the lining of the nasal mucosa, which is rich in dendritic cells that present the antigen(s) to the immune system," said James R. Baker, Jr., M.D., founder and chairman of NanoBio Corp.

"The nanoemulsion adjuvant uniquely interacts with these cells to trigger unparalleled mucosal and systemic immunity," he added.

During the study, the team gave ferrets 7.5, 15 and 45 micrograms of nanoemulsion-adjuvanted influenza vaccine, and found all three doses to produce antibody responses substantially higher than those triggered by the standard intramuscular vaccine.

The ferrets, which represented the most relevant influenza animal model for humans, were then challenged with live influenza virus, and all were protected.

"A large, unmet medical need still exists for protecting people from influenza infection. The robust immunity and antigen-sparing capability demonstrated in this study are especially important for addressing this unmet need, as are the demands for a vaccine that would protect people in the face of a flu pandemic," Baker said.

NanoBio plans to begin a phase 1 clinical study for seasonal influenza in the first half of 2009, and is currently initiating pre-clinical studies in pandemic flu.

The results of the study were presented at the 48th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC)/Infectious Diseases Society of America (IDSA) 46th annual meeting in Washington, D.C.

ANI