SARS-CoV-2 spike protein recombinant (Sf9)

SARS-CoV-2 spike protein recombinant (Sf9) is a protein subunit vaccine candidate developed by the Finnish Institute for Health and Welfare (THL) in collaboration with the University of Helsinki and the University of Eastern Finland. The vaccine utilizes a recombinant version of the SARS-CoV-2 spike protein produced in the *Spodoptera frugiperda* (Sf9) insect cell line using a baculovirus expression system. This traditional protein-based approach is designed to elicit a robust immune response, including the production of neutralizing antibodies and the activation of T-cell mediated immunity against the SARS-CoV-2 virus. The candidate was developed as part of a national effort in Finland to provide a domestic vaccine alternative, primarily targeting COVID-19 infection. It is typically formulated with an adjuvant, such as alum, to enhance its immunogenicity. While the vaccine showed promise in preclinical studies and moved toward early-phase clinical evaluation, its development faced challenges in securing the large-scale funding required for late-stage trials following the widespread availability of other authorized vaccines.

Other names

Finnish COVID-19 protein vaccineTHL COVID-19 vaccineFinnish protein subunit COVID-19 vaccine