VacSIM™ - a new delivery method increases influenza vaccine efficacy (VAC2P.928)

Abstract

Abstract Influenza is a global health issue causing considerable economic burden. Seasonal epidemics of this acute viral infection spread rapidly with unpredictable morbidity. Regular vaccination remains the most effective prevention and as such, there is tremendous need for new technologies focused on improving immunogenicity and efficacy of seasonal flu vaccines. VacSIM™, which stands for Vaccine Self-assembling Immune Matrix, represents a new method of vaccine delivery incorporating an inert biopolymer with unique biophysical properties. It can be stored at 4-22°C, as a viscous-liquid and is flexible enough to incorporate various antigens, adjuvants or organisms for vaccine delivery. Post-injection VacSIM™ undergoes a phase shift to a semi-solid gel, forming a temporary depot of concentrated vaccine components. This gel-matrix depot may slow clearance of the vaccine, simultaneously enabling time-released delivery of the vaccine. We believe the latter increases activation of antigen presenting cells. Mice vaccinated with whole inactivated influenza (A/Puerto Rico/08/34) or with recombinant nucleoprotein via VacSIM™, had an increased humoral response, greater protection from lethal influenza challenge and improved viral clearance from lungs. Studies with other candidate vaccine antigens suggest VacSIM™ is capable of enhancing the immunogenicity and efficacy of a wide variety of vaccines.