Role of COVID-19 Vaccines in SARS-CoV-2 Variants

Abstract

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is a threat to the health of the global population. As the result of a global effort in the determination of origin, structure, and pathogenesis of SARS-CoV-2 and its variants, particularly such the variant of concern as Delta Variant and Omicron Variant, the understanding of SARS-CoV-2 are deepening and the development of vaccines against SARS-CoV-2 are ongoing. Currently, AstraZeneca-Vaxzevria/SII-Covishield vaccine, Janssen-Ad26.COV2.S vaccine, Moderna-mRNA-1273 vaccine, Pfizer BioNTech-Comirnaty vaccine and Sinovac-CoronaVac vaccine have been listed as WHO Emergency Use Listing (EUL) Qualified Vaccines by WHO. Because of the antigen escape caused by the mutation in variants, the effectiveness of vaccines, which are currently the main means of prevention and treatment, has been affected by varying degrees. Herein, we review the current status of mutations of SARS-CoV-2 variants, the different approaches used in the development of COVID-19 vaccines, and COVID-19 vaccine effectiveness against SARS-CoV-2 variants.

COVID-19 Vaccines: An Updated Overview of Different Platforms

“…BNT162b2 (35%), mRNA-1273 (20% after the first dose, 42.8% after the second dose, 67.7% after the third dose), Ad26.COV 2.S (47% after two doses, 63% when given as a booster), and AZD1222 (11.44–51%) all demonstrated activity against the Omicron strain [ 100 , 101 ]. Monoclonal antibodies are also active against Omicron [ 42 ].…”

How far are the new wave of mRNA drugs from us? mRNA product current perspective and future development

“…The year 2020 was a breakthrough year for mRNA, with two mRNA COVID-19 vaccines developed by Pfizer BioNTech and Moderna, respectively, receiving emergency use authorizations. mRNA COVID-19 vaccines will generate global sales of US$58.7 billion in 2021, and both far exceed sales of other COVID-19 vaccines ( 55 , 56 ). mRNA technology can be used primarily in vaccines, immunotherapies, and protein replacement therapies.…”

“…The domestic vaccine industry is expected to compete with overseas markets at the same stage; most of the other indications are in the pre-clinical/early stage. At present, the domestic mRNA research field is dominated by COVID-19 vaccines, while global mRNA drug indications are distributed in (55,56). mRNA technology can be used primarily in vaccines, immunotherapies, and protein replacement therapies.…”

Targeting SARS-CoV-2 and host cell receptor interactions

“…Studies have shown that vaccines prevented 40–65% of symptomatic cases ( Cerqueira-Silva et al, 2022 ). Nevertheless, persistent viral immune escape generated waves of SARS-CoV-2 variants ( Akkiz et al, 2022 ) that are more virulent (Delta strain) or transmissible (Omicron strain), lowering the effectiveness of these vaccines ( Accorsi et al, 2022 ; Andrews et al, 2022 ; Thompson et al, 2022 ; Zhou et al, 2022 ). Implementation of repeat booster vaccination programs, particular within relatively short time-frames have raised questions on long-term immunological implications of repeated vaccines ( El-Menyar et al, 2022 ; Fiolet et al, 2022 ) and prompted efforts to develop vaccines with broader and long-lasting protective effects ( Li, 2022 ; Hussain et al, 2021 ; Li et al, 2021 ).…”