In March 2022 Viravaxx AG filed an international application for a patent concerning a new SARS – CoV – 2 subunit vaccine.

The antigen-based vaccine developed at MedUni Vienna, under the leadership of Rudolf Valenta from the Center for Pathophysiology, Infectiology and Immunology, targets the receptor binding domains (RBD) of the SARS-CoV-2 virus and induced a robust and uniform RBD-specific IgG antibody response in animal models and in human tests. This antibody response prevents the virus from docking onto and entering the body’s cells, so that infection cannot occur.

Combination of coronavirus vaccine and hepatitis B vaccine

The SARS-CoV-2 subunit vaccine (PreS-RBD) developed at MedUni Vienna is based on a structurally folded fusion protein consisting of two receptor binding domains (RBD) of the SARS-CoV-2 virus and the PreS antigen from hepatitis B, which serve as immunological carriers for each other, thereby strengthening the immune response. Currently available genetic SARS-CoV-2 vaccines induce mainly transient IgG1 antibody responses, whereas the PreS-RBD vaccine can additionally induce long-lived RBD-specific IgG4 antibodies.