Drug repurposing or drug repositioning has emerged as an efficient, very
popular and alternative technique in modern drug discovery to identify old drugs for
new targets cost-effectively and dynamically. This concept gets a tremendous boost,
especially in the century's most challenging healthcare concern of the Covid-19
pandemic across the globe. In this approach, scientists seek new indications and
clinical use of the drugs at minimum risk, which have previously already been
pharmacologically established and approved. The methods developed for drug
repositioning include computational approaches and biological methodologies, and
with the fast technological advancement, various new drug-target- diseases are
discovered, and thereby immense information is now available in the different
databases, such as DrugBank, OMIM, ChemBank, KEGG, Pubmed, Genecard, and
many more. The information available on all the above public domain databases has
been utilized successfully in many drug repositioning projects. The present chapter
discusses the concept of drug repurposing and its impact on academia, industries and,
of course, their social implications. Besides this, the chapter will also cover details on
tools and techniques to identify drugs for repositioning and their application in
identifying drugs for various diseases and disorders. The current work will also foresee
the recent market analysis and updates on the cost of drug discovery and development
by drug repurposing, its comparison with traditional drug discovery approaches,
challenges involved with drug repurposing, and future perspectives.
Keywords: Case studies, Drug repositioning, Drug repurposing, in silico approaches, Polypharmacology, Pharmacological approaches.
