In Silico Identification of Widely Used and Well Tolerated Drugs That May Inhibit SARSCov- 2 3C-like Protease and Viral RNA-Dependent RNA Polymerase Activities, and May Have Potential to Be Directly Used in Clinical Trials

Despite drastic strict measures, the spread of the SARS-CoV-2 is ongoing all around the world. There is no vaccine developed against this virus and no approved medication to be used for the treatment of COVID-2019. In this study, we performed in silico screening against two critical enzymes (3C-like protease (3CL^pro) and viral RNA-dependent RNA polymerase (RdRp)), which play important roles in the SARS-CoV-2 life cycle, by using the U.S. Food and Drug Administration (FDA) approved drugs. Our docking simulations enable us to identify several hundred drugs that have high binding affinity for each target. To evaluate persistence of the drugs’ binding to each target near to physiological conditions we selected well tolerated and widely used ones for the molecular dynamics simulations. Simulations results revealed that following drugs were stably interacting with SARS-Cov-2 3CL^pro: tetracycline and its derivatives, dihydroergotamine, ergotamine, dutasteride, nelfinavir, and paliperidone. A similar analysis with RdRp showed that eltrombopag, tipranavir, ergotamine, and conivaptan were bound with the enzyme during the simulation with high binding energy. Detailed analysis of docking results suggested that ergotamine, dihydroergotamine, bromocriptine, dutasteride, conivaptan, paliperidone, and tipranavir can bind to both enzymes with high affinity. Since these drugs are well tolerated, cost effective and widely used, our study suggested that they have potential to be used in clinical trial for the treatment of SARS-CoV-2 infected patients.