Drug-repurposing addresses the efficiency of modern drug-development, which suffers from very high costs (in excess of 1.4 billion per successful drug [3]), long development times, and low-chances of success. In drug-repositioning, currently tested and governmentally-approved drugs are investigated for application to new-diseases.
Since repurposed drugs have already cleared human trials for other reasons, they have known and (and generally relatively mild *) toxicology profiles, their safety and likelihood of successful application are greatly increased.
Further, since many of their clinical and pre-clinical trials have already been cleared, repurposed drugs are generally much cheaper to develop into new applications. This allows drugs to be developed for poorly-funded diseases, such as rare diseases or neglected diseases endemic only to less-developed economic regions.
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