África González-Fernández
Professor of Immunology at the University of Vigo, researcher at the Galicia Sur Research Institute (IIS-GS) and member of the RAFG
This vaccine uses only the protein of the spicule (S), with an adjuvant substance to enhance the response. The technology is partly novel, in the cell type that produces the proteins, in nanoparticulated form, and also in the type of adjuvant used. But recombinant proteins are already used in other vaccines, such as hepatitis B, with great success.
It is a vaccine that has been shown to be very effective against SARS-CoV-2, with 90 % protection against infection with symptoms in clinical trials (when mainly the alpha and beta variants were circulating), and its effect on the omicron variant is not yet known. It has been shown in trials (more than 45,000 recruited persons over 18 years of age) to be very safe, and with very few side effects (arm pain, tiredness, headache and nausea).
The company's proprietary adjuvant, Matrix-M, helps to elicit a potent antibody and T-cell response. It has already been tested in other vaccines, such as a vaccine under study for malaria. An advantage over mRNA vaccines is that it does not require deep-freezing. It can be kept in the refrigerator (between 2 and 8°C), which makes it an excellent vaccine forcountries where the logistics of other vaccines are a problem.
Its efficacy against omicron has yet to be demonstrated, bu it is expected that vaccinated persons will continue to respond to this variant, although its recognition may decrease somewhat.
It is important to point out that this vaccine cannot replicate, does not produce disease and does not integrate.
The vaccine is for intramuscular injection and in two doses 21 days apart, although surely if this period were extended, the immune response generated could be even greater, according to the data obtained with other vaccines.
In summary, we have a new vaccine that can be used, very safely, with high efficacy and with advantages in terms of logistics because it does not require deep freezing. Moreover, the production of the protein will be carried out in a Spanish company, Biofabri, in Porriño, near Vigo, which is very good news.