Intranasal Vaccine Formulation: Advancing Towards Nasal Dry Powder Formulation

Abstract

Unlike conventional mRNA vaccines,intranasal vaccines display several advantages, including the ability to generatestrong mucosal immunity. However,the formulation challenges associated with intranasal mRNA vaccines have so farhindered their extensive application and further research in the area of formulationdevelopment and optimisation are required before translation. This study aimsto optimise the manufacturing conditions of inhalable dry powders by examining theimpact of temperature and lipid composition on liposome particle size and theeffect of spray-drying parameters on the particle size of spray-dried powders. The results indicate that liposomesgenerated at 20°C exhibited notably larger sizes than those produced at 55°C,irrespective of the lipid composition. Notably, dry powder formulations featuringlarger particle sizes were achieved at a low gas flow rate of 25mm.