The use of US FDA-approved drugs is preferred due to the need for lower costs and less time. In in silico medicine, repurposing is a quick and accurate way to screen US FDA-approved medications to find a therapeutic option for COVID-19 infection. Dual inhibitors possess dual inhibitory activity, which may be due to the inhibition of two different enzymes, and are considered better than combination therapy from the developmental and clinical perspectives. In this study, a molecular docking simulation was performed to identify the interactions of antiviral drugs with the critical residues in the binding site of the main SARS-CoV-2 protease, spike glycoprotein, and papain-like protease receptors compared to the angiotensin-converting enzyme-related carboxypeptidase (ACE2) receptor of host cells. Each of the receptors was docked with 70 US FDA-approved antiviral drugs using AutoDock Vina. A molecular dynamics (MD) simulation study was also used for 100 ns to confirm the stability behaviour of the ligand receptor complexes. Among the drugs that had the strongest interaction with the SARS-CoV-2 main protease, spike glycoprotein and papain-like protease receptors, and host cell ACE2 receptors, Simeprevir, Maraviroc and Saquinavir had dual inhibitory effects. The MD simulation study confirmed the stability of the strongest interactions between the antiviral drugs and the main protease, ACE2, spike glycoprotein, and papain-like protease receptors to 100 ns. However the results of MMPBSA analysis showed that the bond between Saquinavir and the ACE2 receptor was weak. Simeprevir and Maraviroc drugs had acceptable binding energies with dual receptors, especially the Simeprevir.Communicated by Ramaswamy H. Sarma.
Keywords: SARS-CoV-2; US FDA-approved; drug repurposing; molecular docking; molecular dynamics (MD) simulation.