The cover photo illustrates the active site or binding pocket of RdRp in the yellow box.
This research is to screen existing approved drugs by the FDA and suggest their reuse for new medical complications. This current research screened 192 antiviral drugs from the DrugBank database for inhibition of the SARS-CoV-2 virus. The author showed that five FDA-approved drugs found after virtual screening showed stable interaction with key residues of the RdRp enzyme including dihydroergotamine, sofosbuvir, nilotinib, tipranavir, and darunavir, which inhibited viral proliferation. The author suggest that these five promising drugs should be further studied in vitro, in vivo, and in clinical trials to combat this widespread infection.
To get more understanding about the topic, please see the full article "In silico screening of drug inhibitors of SARS-CoV-2 RNA-dependent RNA polymerase target" in pages 47-54 in this article.