Mechanism of action for Russia's second Covid-19 vaccine

The second Russian vaccine uses only part of the nCoV protein instead of the whole virus, stimulating the immune system to produce antibodies without side effects.

On October 15, Russia approved a second Covid-19 vaccine, called EpiVacCorona, developed by the Vector Institute. The vaccine contains a small portion of the protein of nCoV, called a peptide, that induces an immune response against Covid-19 and promotes the development of immunity.

EpiVacCorona uses peptides synthesized from viruses, instructing the immune system to recognize and neutralize the virus. The strength of the vaccine is that it is safe and produces little side effects. In addition to preventing infectious agents, peptides are also used to treat cancer.

Modern vaccination programs have become popular since 1796, after Edward Jenner developed a smallpox vaccine, which used an inactivated or attenuated virus, which introduced hundreds of different proteins into the body. Until now, vaccine technology based on all viruses is still common. This is also the method that Chinese manufacturers mainly use to develop their "candidates".

But they have certain weaknesses. Only a small fraction of the protein in the pathogen is responsible for the appropriate protective response. Recent research has shown that allergies or autoimmune conditions can be derived from the residue contained in each injection dose. This occurs because viruses are grown in media containing antibiotics and biological residues. The residue is not completely removed afterwards, often causing an allergic reaction to the user. In addition, the pathogen inactivated or attenuated can reactivate, endangering the patient, the physician and the production unit's personnel.

The EpiVacCorona vaccine, developed by the Vector Institute, approved October 15. Photo: La Noticia

Peptide vaccines such as EpiVacCorona are a potential alternative, helping to solve this problem. The use of one part of protein, rather than the whole virus, to target specific epithelium minimizes the risk of allergies or autoimmune. Suitable for large-scale production, cost effective injection. The formulation does not contain ingredients that cause biological pollution.

However, developing vaccines based on this technology still presents a significant challenge. Peptides are very small in size, sometimes do not induce a permanent immune response. These molecules are also unstable in the body and are easily broken down by enzymes before they can react properly.

On October 5, the Federal Agency for Supervision for the Protection of Consumers' Rights and Health said that nearly 30,000 volunteers will participate in the EpiVacCorona vaccine trial. This is a test that combines the first and second stage of the product. Scientists will use a placebo to control the effectiveness.

The previous study involved 100 volunteers, aged between 18 and 60. The results have yet to be published. Phase three testing has not yet begun either.

In August, Russia became the first country in the world to give urgent approval of the Covid-19 vaccine. Scientists are still concerned about this move, saying that Sputnik V is not safe and effective enough to distribute to people. However, Russian President Vladimir Putin insists that the injections do not have serious side effects. His daughter was also among the first to use the vaccine.