Unlocking Hidden Potential: Strategies and Success Stories in Drug Repurposing for Modern Medicine

Drug repurposing, also known as drug repositioning or reprofiling, is an accelerated and highly cost-effective strategy in pharmaceutical development that involves finding new clinical applications for existing, approved, or investigational drugs outside of their original intended use. This approach offers significant advantages over traditional drug discovery, including a reduced timeline (3–12 years versus 10–15 years) and dramatically lower development costs (often under $500 million compared to billions), primarily because the drugs have already undergone extensive safety and toxicity testing in humans. This allows for a bypass of the rigorous and time-consuming Phase I clinical trials, moving directly into Phase II and III efficacy testing for the new indication, thereby drastically mitigating the high failure rate characteristic of novel drug development.

The success of drug repurposing is evident in historical examples such as sildenafil (Viagra), which was originally investigated for hypertension and angina before being repurposed for erectile dysfunction, and thalidomide, which was notoriously removed as a sedative but successfully repurposed for leprosy and multiple myeloma. Today, sophisticated methodologies, including in silico screening powered by AI and knowledge-based approaches utilizing vast amounts of biomedical data, are being employed to systematically identify promising candidates for diseases like cancer, neurodegenerative disorders, and emerging viral threats, as demonstrated by the rapid repurposing efforts during the COVID-19 pandemic. This innovative strategy capitalizes on the known pharmacological and safety profile of the compound to quickly provide new therapeutic options for unmet medical needs.