Development of vaccines against COVID-19 using VLPs

The new coronavirus, called SARS-CoV-2/Covid-19, apparently emerged in Wuhan, China, in late December 2019, has quickly become a public health problem on a global scale, and is not anticipated to control this pandemic , nor the human and financial damage that this new virus can cause. Vaccination remains one of the most effective ways to control and prevent infectious diseases. Although a large number of studies in vaccine development have focused on the use of attenuated, inactivated pathogens, or DNA or RNA-based vaccines, a safe and effective way to develop vaccines is to use protein antigens. However, an obstacle to vaccines based on subunit antigens is the typically low immunogenicity they elicit. Even so, due to the urgent need to develop an effective and safe vaccine to fight this pandemic that has frightened the population around the world, there is also a market race that leads us to reflect on the paths that the development of a vaccine can take. Safety should be the determining factor for the development of this vaccine, as knowledge of Covid-19 is still limited. Therefore, there is a need to follow all scientific technical rigors before taking any vaccine formulation for clinical trials. Something our team initially ruled out was the use of genetic material to develop this vaccine. We therefore focus on using the virus binding domain to the cellular receptor (Receptor Binding Domain-RBD) found in the spike protein of the virus. Although, the use of protein fragments, although safe and assertive in the development of a vaccine, is not capable of inducing an effective and protective immune response. To meet this need, we incorporated this project to develop an anti-COVID-19 vaccine into the FAPESP-approved Young Researcher project (Case number: 2019/14526-0) recently approved to develop vaccines against Streptococcus pyogenes and Chikungunya, based on Virus-like particles (VLPs). VLPs are multi-protein structures that carry characteristics of viruses but exclude their ability to replicate because they do not contain the viral genome. VLPs are a well-characterized class of non-infectious and biodegradable nanoparticles that have been used successfully in humans for vaccine development.