Role of Drug Repurposing in Sustainable Drug Discovery

Abstract

The contemporary global drug discovery scenario, in spite of several technological advances, is heavily ridden with multiple challenges of a dynamic regulatory system, escalating costs from bench to bedside investigational drugs, the increased probability of withdrawal after launch, and overstretched timelines from discovery to approval, among others. Drug repurposing/repositioning/re-profiling/re-tasking is an effective and practical complimentary method for the selection of alternate therapies for approved, shelved, discontinued/abandoned, and investigational drugs or new chemical entities, with the parallel study of new metabolic pathways and/or protein targets. Such an approach encompasses multipronged benefits of redundant preclini-cal testing, toxicity evaluation, and formulation studies, based largely on serendip-ity. In recent years, approaches have been driven by artificial intelligence (AI) and machine learning, and bioinformatics have opened up new vistas in drug re-profiling acceleration. Increasing protocols to club the shared mechanisms among structurally diverse/dissimilar drugs include pathway analysis, phenotypic screening, signature matching, related disease genes, binding assay studies, molecular docking, and clinical data monitoring. All in all, repositioning of abandoned/investigational/existing drugs or new chemical entities for other therapeutic indications could enhance the overall productivity of the pharmaceutical industry while paradigmatically shifting the focus from new drug discovery to the optimization of available resources.