Preparing an Adjuvanted Thermoresponsive Gel Formulation for Sublingual Vaccination.

Thermoresponsive gels have unique physicochemical properties that may enable more effective mucosal delivery of active compounds. The thermoresponsive gel (TRG) formulation developed by our group for sublingual delivery maintains fluid-like liquid properties at 2 °C-8 °C and forms a gel at the physiological temperature (~37 °C) within a few seconds. Here, we describe the preparation of a thermoresponsive gel vaccine formulation. Our preclinical studies with various antigens suggest that the mucoadhesive, adjuvanted TRG formulation enabled increased contact of the vaccine antigen with the mucosa, resulting in increased mucosal response(s) with a potential for antigen dose reduction.