Serendipity vs. Science
Unexpected drug effects are not limited to only adverse drug reactions. Some effects turn out to be beneficial, or even to be an unexpected breakthrough in the treatment of another disease.
A vivid example is the accidental discovery of sildenafil as an agent for erectile dysfunction – a substance originally developed as a medication for angina pectoris.
However, unexpected beneficial effects are not only observed in novel drugs, but especially in well-known and widely used older substances and may lead to a wider scope of application. The following table lists some examples of how initial or intended indications may shift or extend: Click here to view the table
In the case of Sildenafil, mere chance may have been the trigger for a new discovery. However, with the continuous evolution of translational sciences, its novel technologies and improved pathogenic understanding, drug repurposing could become an increasingly dynamic process.