Drug Repurposing Approaches: Existing Leads for Novel Threats and Drug Targets

Drug Repurposing (DR) is an alternative to the traditional drug discovery process. It is cost and time effective,with high returns and low-risk process that can tackle the increasing need for interventions for varied diseases and new outbreaks. Repurposing of old drugs for other diseases has gained wider attention, as there have been several old drugs approved by the FDA for new diseases. In the global emergency of COVID-19 pandemic, this is one of the strategies implemented in the repurposing of old anti-infective, anti-rheumatic and anti-thrombotic drugs. The goal of the current review is to elaborate the process of DR, its advantages, repurposed drugs for a plethora of disorders, and the evolution of related academic publications. Further, detailed are the computational approaches: literature mining and semantic inference, network-based drug repositioning, signature matching, retrospective clinical analysis, molecular docking and experimental phenotypic screening. We discuss the legal and economic potential barriers in DR, existent collaborative models and recommendations for overcoming these hurdles and leveraging the complete potential of DR in finding new indications.