Technical transfer of a rapid microbial platform for vaccine production

The limited availability and affordability of vaccines to low- and middle-income countries (LMIC) has created a need for solutions that will ensure effective, affordable vaccine production technology. To establish a rapid and economical platform for the expression of viral proteins in high yield and purity by Pichia pastoris (X33), the receptor-binding domain (RBD) protein of the SARS-CoV2 was selected in this study. After fermentation at the 5 L scale, the protein was purified by a simplified chromatography, with minimal sample treatment. The purified protein was characterized biochemically, and after its formulation, the immunogenicity was evaluated in mice. Collectively, the data suggested that the vaccine candidate is a suitable COVID-19 vaccine candidate antigen for technology transfer. Furthermore, this study creates a robust foundation for industrial production at scale.