Binding and inhibitory effect of ravidasvir on 3CLpro of SARS-CoV-2: a molecular docking, molecular dynamics and MM/PBSA approach.

Drug repurposing requires a limited resource, cost-effective and faster method to combat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, this in silico studies attempts to identify the drug-likeness properties of ravidasvir, an II/III phase clinical trial chronic hepatitis C drug against 3-Chymotrypsin-like protease (3CLpro) of SARS-CoV-2 to combat the ongoing coronavirus disease 2019 (COVID-19) pandemic. This protease is predominantly involved in virus replication cycle; hence it is considered as a potent drug target. The molecular docking results showed that ravidasvir was found to be potent inhibitors of 3CLpro with scoring function based binding energy is -26.7 kJ/mol. Further dynamic behaviour of apo form and complex form of ravidasvir with 3CLpro were studied using molecular dynamics (MD) simulations over 500 ns each, total 2 µs time scale. The motion of the protein was studied using principal component analysis of the MD simulation trajectories. The binding free energy calculated using MM/PBSA method from the MD simulation trajectory was -190.3 ± 70.2 kJ/mol and -106.0 ± 26.7 kJ/mol for GROMOS96 54A7 and AMBER99SB-ILDN force field, respectively. This in silico studies suggesting ravidasvir might be a potential lead molecule against SARS-CoV-2 for further optimization and drug development to combat the life-threatening COVID-19 pandemic.Communicated by Ramaswamy H. Sarma.