Computational Techniques for Drug Repurposing: A Paradigm Shift in Drug Discovery

The last two years from 2020 to 2022 have seen the world face an unparalleled crisis in the form of the corona virus, which has challenged mankind as never before. The struggle and race to find a cure for the disease kept medical professionals, pharmacists, and scientists on their toes. Drug discovery by de novo approach was not an option due to its obvious downside of the enormous time required for the process. Hitherto unknown in public parlance, repurposing existing drugs showed the way forward for scientists. Drug repurposing involves redefining medical use for drugs that have crossed the drug discovery process and were approved, discontinued, or shelved. Drug repurposing or repositioning has shown effective results in treating several diseases. This review traces the journey of some repurposed drugs and provides an overview of computational methods used for repurposing, which include signature mapping, molecular docking, and in silico approaches. The review also highlights repurposed drugs for cancer, one of the most dreaded diseases, and how repurposing can prove to be a boon for many types of cancers. Concerted efforts to study this modality of drug discovery are the need of the hour. The article discusses various drugs which have been successfully repurposed for the treatment of a plethora of diseases. Drug repurposing is a silver lining that can reduce the arduous journey of discovering a definitive cure for a disease and has the potential to change the landscape of the drug discovery process.