Variations of drug repurposing

The term ‘drug repurposing’ is often used interchangeably with ‘drug repositioning’. Here, we use drug repurposing to refer to a generic drug being used for a new condition, whereas drug repositioning involves re-developing a patented drug (that may be available on the market for a different condition or that might have been shelved by the developing company).
Drug reprofiling is an additional variation of drug repurposing that involves slightly altering an approved drug for a new indication, by creating an isomer (a version with tiny variations), a pro-drug (a compound that breaks down in the body to release a known drug), or a metabolite (the piece of a drug that the body uses to tackle a disease)
Drug reformulation involves taking an existing approved drug and creating a new delivery form (e.g. taking a medication applied to the skin and making it into an oral drug), or a new dosage (e.g. original formulation is provided as 100 mg tablets and the new drug is provided as 1 mg tablets). Reformulating a drug can generate novel intellectual property, potentially opening up new business opportunities.