Repurposing generics can have groundbreaking effects for patients: 35% of transformative drugs approved by the US FDA are repurposed products. Repurposing is especially relevant for rare or neglected diseases.
A number of successes have been achieved, the foremost including sildenafil (Viagra) for erectile dysfunction and pulmonary hypertension and thalidomide for leprosy and multiple myeloma. Clinical trials have been performed on posaconazole and ravuconazole for Chagas disease.
Other antifungal agents clotrimazole and ketoconazole have been investigated for anti-trypanosome therapy. Successful repositioning of antimicrobials has led to the discovery of broad-spectrum therapeutics, which are effective against multiple infection types.