GelVac™ Nasal Influenza Vaccine

GelVac™ Nasal Influenza Vaccine is based on a novel plant polysaccharide (GelSite^® polymer) and its gelling property to encapsulate vaccine/adjuvant formulation as gel particles that may potentially (1) enhance the immune response, (2) reduce the antigen and/or adjuvant dose, and/or (3) eliminate the boosting dose through a combination of several factors including sustained antigen release, improved antigen uptake, and improved antigen stability. Nanotherapeutics plans to conduct a Phase I safety and immunogenicity study of a GelVac™ nasal powder H5N1 influenza vaccine that possesses distinct potential advantages in meeting the critical needs of pandemic preparedness.
The vaccine consists of the GelVac™ nasal powder formulation in combination with an inactivated cell-based influenza H5N1 whole virion antigen (A/Vietnam/1203/2004). The powder vaccine formulation is filled into a positive pressure nasal delivery device and delivered into the nasal cavity by compressed air. GelSite^® polymer has been tested in various vaccine formulations for administration by the nasal route and injection, including an in-situ gelling nasal powder influenza vaccine which is entering Phase 1 clinical studies. GelSite^® polymer has been shown to have an adjuvant-like effect - increasing immune response and antigen sparing when administered together with the antigen by intramuscular injection. GelSite polymer is inert and the polymer gel does not support cell adjesion. The adjuvant effect is most likely due to the sustained release by in-situ gelation at the injection site. This adjuvant effect can be obtained at a very polymer concentration, lower than that of the alum adjuvant commonly used in licensed vaccines.

GelSite^®

GelSite^® polymer is a chemically and functionally distinct high molecular weight anionic polysaccharide (sodium polygalacturonate, CAS RN 119758-46-2) extracted from Aloe vera L., a succulent plant widely cultivated in the tropical and subtropical regions. It belongs to the pectin class of the plant polysaccharides and is generall considered as safe (GRAS). GelSite^® polymer possesses distinctive chemical and functional properties. It is characterized by a high galacturonic acid (Gal UA) content of >90%, an exceptionally low DM (degree of methylation) of <10%, and a high molecular weight of > 400 kDa (weight average). A combination of these chemical properties has not been described previously for a pectic substance. GelSite^® polymer is manufactured under cGMP at a kilogram scale with a purity > 99%.  A type IV Master File has been filed with CDER and CBER of the FDA.