In-Vitro Screening of Repurposed Drug Library against Severe Acute Respiratory Syndrome Coronavirus-2

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Gudepalya Renukaiah Rudramurthy Radha Krishan Shandil Shridhar Narayanan


The current pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) demands rapid identification of new antiviral molecules from the existing drugs. Drug repurposing is a significant alternative for pandemics and emerging diseases because of the availability of preclinical data, documented safety in clinic and possibility of immediate production and scalable capacity and supply. Several drugs such as ivermectin and hydroxy chloroquine have been repurposed as anti-SARS-CoV-2 agents, but the effect of these compounds in treating the COVID-19 patients remains sub-optimal. In the present study repurposed drug libraries consisting of 560 compounds from two different sources have been screened against SARS-CoV-2 isolate USA-WA1/2020 in Vero-E6 cell line and 24 compounds were found active. The SARS-CoV-2 virus propagated in Vero E6 cell line and used in screening the drug libraries was sequenced by Next Generation Sequencing to identify any mutations that may have accumulated in the virus genome. The whole genome sequencing data of SARS-CoV-2 showed 9 and 6 single nucleotide polymorphisms in spike protein with reference to Wuhan-Hu-1(NC045512.2) and USA/WA-CDC-WA1/2020 (MN985325.1) isolates respectively. The present study identified 24 compounds active against SARS-CoV-2 isolate USA-WA1/2020 out of 560 repurposed drugs from two libraries. The IC-50 values of the identified hits range from 0.4 µM to 16 µM. Further studies on the repurposed drugs identified in the present screen may be helpful in the rapid development of antiviral drugs against SARS-CoV-2.

Keywords: COVID-19, dose response curve, IC-50, NGS, repurposed drugs, SARS-CoV-2, SNPs, Vero E6

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RUDRAMURTHY, Gudepalya Renukaiah; SHANDIL, Radha Krishan; NARAYANAN, Shridhar. In-Vitro Screening of Repurposed Drug Library against Severe Acute Respiratory Syndrome Coronavirus-2. Medical Research Archives, [S.l.], v. 11, n. 2, feb. 2023. ISSN 2375-1924. Available at: <>. Date accessed: 09 dec. 2023. doi:
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