Patent applications may also be based on new uses (e.g. repurposing) for previously-known medicines. For example, aspirin is well known for the treatment of headaches. If it was now found that it could be used to treat colon cancer, then a new patent application could be filed which claimed uses of aspirin to treat colon cancer.
Inventions based on the discovery of such new uses are claimed in different formats depending on the country where the patent application is filed. (The main reason for this is that most countries do not allow methods of treatments to be claimed directly, the most notable exception to this being the US.)
Examples of allowable formats include the following:
A method of treating colon cancer, comprising administering an effective amount of aspirin to a patient in need thereof
Aspirin for use in a method of treating colon cancer
Use of aspirin in the manufacture of a medicament for the treatment of colon cancer