Drug repositioning: Re-investigating existing drugs for new therapeutic indications

Abstract

Drug discovery and development is an expensive, time-consuming, and risky enterprise. In order to accelerate the drug development process with reduced risk of failure and relatively lower costs, pharmaceutical companies have adopted drug repositioning as an alternative. This strategy involves exploration of drugs that have already been approved for treatment of other diseases and/or whose targets have already been discovered. Various techniques including data mining, bioinformatics, and usage of novel screening platforms have been used for identification and screening of potential repositioning candidates. However, challenges in clinical trials and intellectual property issues may be encountered during the repositioning process. Nevertheless, such initiatives not only add value to the portfolio of pharmaceutical companies but also provide an opportunity for academia and government laboratories to develop new and innovative uses of existing drugs for infectious and neglected diseases, especially in emerging countries like India.

The renin-angiotensin system meets the hallmarks of cancer

“…First, the use of RAS blockers could improve the prognosis of the patients, and second, the finding of a new therapeutic use for a proven drug has the advantage of decreased development costs and decreased time to market compared to traditional discovery efforts because of the availability of previously collected pharmacokinetic, toxicology and safety data. 39 RAS is expressed in many tissues and has diverse functions; when considering the use of its inhibitors as part of a coadjutant treatment in cancer, the potential benefits of their use should be balanced against their adverse effects such as angioedema, hypotensive symptoms, cough, syncope, diarrhoea, renal insufficiency and hyperkalaemia. 40 Epidemiologic studies have been controversial regarding the use of antihypertensive drugs as a risk or protective factor for cancer.…”

Ameliorative effect of methylthiouracil on TGFBIp-induced septic responses

“…Many agents approved for other uses already have been tested in humans, so detailed information is available on their pharmacology, formulation and potential toxicity. Because repositioning builds upon previous research and development efforts, new candidate therapies could be ready for clinical trials quickly, speeding their review by the FDA and, if approved, integration into health care [2,3].…”

“…However, developing a brand-new drug takes an enormous amount of time, money and effort, mainly because of bottlenecks in the therapeutic development process [1]. "Repositioning" generally refers to studying a compound or biologic (referred to as agents) to treat one disease or condition to see if it is safe and effective for treating other diseases [2,3]. Many agents approved for other uses already have been tested in humans, so detailed information is available on their pharmacology, formulation and potential toxicity.…”

Selection of Molecular Targets for Drug Development Against Trypanosomatids

“…Nowadays, as more and more pharmaceutical companies are exploring the existing arsenal of known drugs for repositioning candidates, the number of repositioning successful stories is steadily increasing (Padhy and Gupta 2011 ). Thus, the exploitation of drugs whose targets have already been discovered in other systems can offer advantages for both drug target identifi cation and antiparasitic drug discovery.…”