All the companies running to find the coronavirus vaccine

Since the genetic sequence of the SARS-CoV-2 virus was published on January 11, 2020, scientists, industries and other organizations around the world have worked together to develop safe and effective vaccines against COVID-19 as soon as possible. According to the overview of the World Health Organization (WHO), as of 22 January 2021 there were 237 candidate vaccines under development, of which 173 in the pre-clinical phase and 64 in the clinical phase (16 of the latter in phase 3). Two vaccines have been authorized in Europe so far, both mRNA vaccines, the first produced by the company BioNTech / Pfizer, and approved by the European Medicines Agency (EMA) on 21 December 2020, the second produced by Moderna and approved by the EMA on January 6, 2021. Then it should be the turn of the vaccines developed by the University of Oxford-AstraZeneca and by Johnson & Johnson.

Some vaccines are made using the same technology (or “platform”) as vaccines currently in use, others are made using new approaches or approaches recently used in the development of SARS and Ebola vaccines. The goal of all these vaccines is to produce an immune response in order to neutralize the virus and prevent cell infection. The main platforms used are the following:

Inactivated Viral Vaccines: Produced by culturing the SARS-CoV-2 virus in cell cultures and chemically inactivating it; Live attenuated vaccines: produced by generating a genetically weakened version of the virus that replicates to a limited extent, not causing disease but inducing immune responses similar to those induced by natural infection; Recombinant protein vaccines: based on the spike protein, or on the receptor binding domain (RBD) or on virus-like particles (VLP); Viral vector vaccines: Typically based on an existing virus (usually an incompetent adenovirus for replication) that carries the sequence of the genetic code that encodes the spike protein; DNA vaccines: based on plasmids, modified to carry genes that generally code for the spike protein that is then produced in the vaccinated individual; RNA vaccines: based on messenger RNA (mRNA) or a self-replicating RNA that provides the genetic information for the spike protein.

Candidate vaccines are tested first in the laboratory, then on animals, and finally on human volunteers. The studies examined must therefore be able to confirm the efficacy and safety of vaccines and that their benefits outweigh any potential side effects or risks. As COVID-19 vaccines are administered, EMA will promptly identify and evaluate new information and data that emerge with respect to benefits and safety, and monitor any reported side effects from post-marketing surveillance. EMA evaluates COVID-19 vaccines against the same high standards of quality, safety and efficacy as are applied to all other drugs to be placed on the market.