A Systematic Review on the Emergence of Omicron Variant and Recent Advancement in Therapies

Abstract

With the ongoing COVID-19 pandemic, the emergence of the novel Omicron variant in November 2021 has created chaos around the world. Despite mass vaccination, Omicron has spread rapidly, raising concerns around the globe. The Omicron variant has a vast array of mutations, as compared to another variant of concern, with a total of 50 mutations, 30 of which are present on its spike protein alone. These mutations have led to immune escape and more transmissibility compared to other variants, including the Delta variant. A cluster of mutations (H655Y, N679K, and P681H) present in the Omicron spike protein could aid in transmission. Currently, no virus-specific data are available to predict the efficacy of the anti-viral and mAbs drugs. However, two monoclonal antibody drugs, Sotrovimab and Evusheld, are authorized for emergency use in COVID-19 patients. This virus is not fading away soon. The easiest solution and least expensive measure to fight against this pandemic are to follow the appropriate COVID-19 protocols. There is a need to strengthen the level of research for the development of potential vaccines and anti-viral drugs. It is also important to monitor and expand the genomic surveillance to keep track of the emergence of new variants, thus avoiding the spread of new diseases worldwide. This article highlights the emergence of the new SARS-CoV-2 variant of concern, Omicron (B.1.1.529), and the vast number of mutations in its protein. In addition, recent advancements in drugs approved by FDA to treat COVID patients have been listed and focused in this paper.

The Potential of Nanobodies for COVID-19 Diagnostics and Therapeutics

“…Since the Alpha variant cases have decreased considerably, the S− results (suspect Omicron infection) could be used as a marker, together with sequencing, for Omicron detection [ 13 , 25 ]. However, variants do have sub-lineages and the Omicron BA.2 sub-lineage does not contain the 69–70 deletion, hence it is S+ [ 6 ]. Therefore, whole-genome sequencing with next-generation sequencing is required for confirmation of the Omicron variant even though it is a lengthy and expensive process [ 6 , 26 ].…”

“…However, variants do have sub-lineages and the Omicron BA.2 sub-lineage does not contain the 69–70 deletion, hence it is S+ [ 6 ]. Therefore, whole-genome sequencing with next-generation sequencing is required for confirmation of the Omicron variant even though it is a lengthy and expensive process [ 6 , 26 ].…”

“…Each of these variants lead to a new wave of infections and can potentially evade host immunity (developed post infection or vaccination) as well as therapeutics [ 14 , 15 ]. Notably, the Omicron variant has been shown to be more transmissible, have an increased rate of infections, higher re-infection risk profile, greater immune escape capabilities and the largest number of mutations compared with the other variants (Table 1 ) [ 6 , 13 , 15 ]. Notably, individuals infected with the Delta and Beta variant have a 40% and 60% chance of re-infection with the Omicron variant, respectively [ 13 ].…”

“…Mutations in the S protein, such as E484K and N501Y, have been identified in the Brazil, SA, and UK variants (Table 1 ) [ 16 ]. Mutations such as D614G, N501Y, and K417N allow the virus to be more infectious, while the H655Y, N679K, and P681H mutations allow the virus to be more transmissible [ 6 ]. These mutations alter RBD epitopes, allow the virus to escape Ab neutralization, evade host immune responses, may render treatments ineffective [ 4 ], and enhance receptor binding specificity, virus growth [ 16 ], infectivity and virulence [ 17 ].…”

“…This highly contagious virus has swiftly spread throughout the globe, leading to coronavirus disease 2019 (COVID-19) [ 4 , 5 ] being declared a pandemic in March 2020 [ 3 ]. There have been more than 585 million COVID-19 cases and more than 6 million fatalities [ 6 ] worldwide [ 4 , 5 ]. Virus transmission may occur through direct contact with infected individuals and exposure to SARS-CoV-2-contaminated liquid droplets, surfaces and materials [ 3 ].…”