Thin-film freeze-drying of a bivalent Norovirus vaccine while maintaining the potency of both antigens
A bivalent Norovirus vaccine candidate has been developed that contains Norovirus strain GI.1 Norwalk-virus like particles (VLP) and strain GII.4 Consensus VLPadsorbed on aluminum (oxy)hydroxide. The Norwalk and Consensus antigens have different stability profiles, making it challenging to prepare a dry powder form of the Norovirus vaccine while maintaining the potency of both antigens.
In the present study, we tested the feasibility of converting the vaccine from a liquid suspension to dry powders by thin-film freeze-drying (TFFD). With the proper amount of trehalose and/or sucrose as cryoprotectant (i.e. sucrose alone at 4.55% or 5.55%, w/v, or trehalose at 3-4% with 0.55% of sucrose), TFFD can be applied to successfully convert the Norovirus vaccine candidate into dry powders without causing antigen loss or particle aggregation, while maintaining the relative potency of the antigens within a specified acceptable range.
In an accelerated stability study, the potency of the antigens was also maintained in the specified acceptable range after the dry powders prepared by thin-film freeze-drying in the presence of 5.55% (w/v) of sucrose were stored for eight weeks at 40°C, 75% relative humidity. It is concluded that it is feasible to apply thin-film freeze-drying to convert Norovirus vaccine from a liquid suspension to stable dry powders.
Article information: Haiyue Xu, Tuhin Bhowmik, Kevin Gong, Thu Ngoc Anh Huynh, Robert O. Williams III, Zhengrong Cui, Thin-film freeze-drying of a bivalent Norovirus vaccine while maintaining the potency of both antigens, International Journal of Pharmaceutics, 2021. https://doi.org/10.1016/j.ijpharm.2021.121126.