Development of a solid dosage platform for the oral delivery of bilayer vesicles

Within this work, we develop vesicles incorporating sub-unit antigens as solid dosage forms suitable for the oral delivery of vaccines. Using a combination of trehalose, dextran and mannitol, freeze-dried oral disintegrating tablets were formed which upon rehydration release bilayer vesicles incorporating antigen. Initial studies focused on the optimisation of the freeze-dry cycle and subsequently excipient content was optimised by testing tablet hardness, disintegration time and moisture content. The use of 10 % mannitol and 10 % dextran produced durable tablets which offered strong resistance to mechanical damage yet appropriate disintegration times and dispersed to release niosomes-entrapping antigen. From these studies, we have formulated a bilayer vesicle vaccine delivery system as rapid disintegrating tablets and capsules. The data included here has the raw data from:
Figure 4. The result of varying mannitol and dextran ratios within the vesicle mixture where; A) outlines the vesicle characteristics, B) presents the appearance of the tablets, their hardness and disintegration time and C) their moisture content (n=5).
Figure 5. Vesicles containing antigen formatted as liquids, a freeze-dried tablet and ODTs where A) shows the various formulations B) shows antigen incorporation, C), outlines the vesicle characteristics and D) the disintegration time (n = 5).

This work was made possible via funding from Variation Biotechnologies and a BBSRC Industrial Case studentship (BB/G017948/1).