(Vienna, 11 March 2024) Researchers at the Center for Pathophysiology, Infectiology and Immunology at the Medical University of Vienna have further developed their Covid-19 vaccine, which has now shown promise in the fight against the Omikron variant of the virus. The results of their work were recently published in the top journal "Vaccines".
COVID-19, caused by the SARS-CoV-2 virus, has now spread worldwide. The Omicron variant and its subtypes dominate since November 2021. To prevent severe courses of the disease, vaccines are needed that induce antibodies that are effective against Omicron.
The MedUni Vienna team led by Rudolf Valenta and Pia Gattinger has improved the COVID-19 vaccine developed at MedUni Vienna, which consists of the PreS protein of the hepatitis B virus (HBV) and two RBD proteins of SARS-CoV-2, so that it is highly effective against Omicron. Different vaccine variants were developed, produced and compared in their study.
The results in the animal model showed that the chimeric PreS-RBD subunit vaccine, called W-PreS-O, which consists of components of the original SARS-CoV-2 virus and Omicron, induced the highest neutralizing antibody titers against Omicron. Interestingly, the RBD-specific antibody levels induced by the different vaccines were comparable, but the virus neutralization titers against Omckron induced by W-PreS-O were up to sevenfold higher than the strain-specific and bivalent vaccines. This suggests that W-PreS-O is a particularly promising candidate for further preclinical and clinical studies.
"I think it is a very important work because there are currently little to no protection options for COVID-19 caused by the current virus variants, especially for vulnerable patients," explains study leader Rudolf Valenta, "it is remarkable that the combination vaccine works better against Omicron than the vaccine adapted "only" for Omicron. It is especially interesting that it is not only the antibody levels that matter, but rather their neutralizing effect that is better with the combination vaccine."
The research results are an important step in the continuing fight against COVID-19 and could help to develop vaccines that are even better adapted to the currently circulating virus variants.
Publikation: Vaccines
Gattinger, P.; Kratzer, B.; Sehgal, A.N.A.; Ohradanova-Repic, A.; Gebetsberger, L.; Tajti, G.; Focke-Tejkl, M.; Schaar, M.; Fuhrmann, V.; Petrowitsch, L.; et al. Vaccine Based on Recombinant Fusion Protein Combining Hepatitis B Virus PreS with SARS-CoV-2 Wild-Type- and Omicron-Derived Receptor Binding Domain Strongly Induces Omicron-Neutralizing Antibodies in a Murine Model. Vaccines 2024, 12, 229. https://doi.org/10.3390/vaccines12030229