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RESEARCH ARTICLE (Open Access)

Perspectives for antivirals to limit SARS-CoV-2 infection (COVID-19)

Erik De Clercq
+ Author Affiliations
- Author Affiliations

KU Leuven, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Herestraat 49, 3000 Leuven, Belgium. Tel.: + 32 16 37 90 20; Email: erik.declercq@kuleuven.be

Microbiology Australia 42(1) 47-53 https://doi.org/10.1071/MA21013
Submitted: 5 February 2021  Accepted: 3 March 2021   Published: 12 April 2021

Journal Compilation © The Authors 2021 Open Access CC BY, published (by CSIRO Publishing) on behalf of the ASM

Abstract

Compared with vaccines, antivirals for curbing COVID-19 (SARS-CoV-2 infection) have been developed at a much lower pace. Favipiravir has proven efficacious (in hamsters) but only at a very high dose which may not be feasible in humans. Remdesivir is the sole antiviral approved by the US FDA, but it has not been extensively evaluated for its safety. EIDD-1931 and EIDD-2801 have not been evaluated clinically. Mpro (protease) inhibitors likewise need to be subjected to clinical efficacy and safety studies. Remdesivir is a C-nucleoside and this class of compounds should be further evaluated. Polyanionic substances interfering with virus adsorption to the host cells have not been explored. They may possibly be administered by inhalation. Corticosteroids (such as dexamethasone), while virus-stimulating rather than inhibitory, may counteract the ‘cytokine storm’. Combination of (two or more of) the compounds mentioned above may offer an increased benefit through a synergistic interaction.


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