SARS-CoV-2: Vaccinology and Emerging therapeutics; Challenges and Future Developments

Abstract

As SARS-CoV-2 emerge, variants such as Omicron (B.1.1.529), Delta (B.1.617.2), and those from the United Kingdom (B.1.1.7), South Africa (B.1.351), Brazil (P.1) and India (B.1.6.17 lineage) have raised concerns of the reduced neutralising ability of antibodies and increased ability to evade the current six approved COVID-19 vaccine candidates. This viewpoint advocates for countries to conduct prior efficacy studies before they embark on mass vaccination and addresses the role of nanoparticles as carrier vehicles for these vaccines with a view to explore the present challenges and forge a path for a stronger and more viable future for the development of vaccines for SARS-CoV-2 and future pandemics. We also look at the emerging prophylactics and therapeutics in the light of ongoing cases of severe and critical COVID-19.

An overview on inactivated and live‐attenuated SARS‐CoV‐2 vaccines

“…In general, these vaccines fall into four categories: nucleic acid, viral vector, whole pathogen, and protein vaccines. 71 Vaccines based on nucleic acids use genetic materials (mRNA, DNA, and siRNA) that can produce specific proteins inducing antibodies and stimulate memory T cell. 72 Viral vector vaccines are genetically modified and safe viruses that fail to produce specific immunogenic proteins.…”

“…Protein‐based vaccines are actually whole recombinant spike proteins packaged in nanoparticles. 71 Inactivated vaccines are a type of whole pathogen vaccine. This type of vaccines are the oldest and most well‐known vaccines because they contain the whole attenuated or inactivated pathogen that produces the immune response.…”

“…The remarkable point is that nucleic acid‐based vaccines are slower to develop than other types of vaccines, but they are safe and effective. 71 …”

“…So far, different types of vaccines have been designed to prevent COVID‐19 and have been tested in various laboratory phases. In general, these vaccines fall into four categories: nucleic acid, viral vector, whole pathogen, and protein vaccines 71 72 …”

“…Viral vector vaccines are genetically modified and safe viruses that fail to produce specific immunogenic proteins. Protein‐based vaccines are actually whole recombinant spike proteins packaged in nanoparticles 71 . Inactivated vaccines are a type of whole pathogen vaccine.…”