Preparation for the challenge of heavily mutated Omicron variant

Abstract

The receptor-binding domain (RBD) in the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to the angiotensin-converting enzyme-2 on the host cell surface with high affinity, which is the origin of several SARS-CoV-2 variants.3 Many changes had little to no impact on the virus’ properties. R203K/G204R mutations would increase adaptability by the virus evolution analysis using the computation biology analysis.4 In addition, the Omicron variant also had several mutations that did not report previously, whether they would enhance its infectivity and the disease severity, their roles should be clarified. The emergence of antibodies against SARS-CoV-2 which produced protective antibodies and induced memory cells may be activated in response to subsequent exposure to SARS-CoV-2 and its variants.11 Recently, a novel COVID-19 oral antiviral candidate PF-07321332 (Paxlovid) reduced the risk of hospitalization or death by 89% compared to placebo in an interim analysis of phase II/III study by Pfizer.12 PF-07321332 was designed to block the activity of the SARS-CoV-2-3CL protease, an enzyme that participated in virus replication.