**3. Application of inhibitors in drug repurposing**

In oncology, repurposing of drugs means the reuse of already existing drugs to treat cancer rather than testing new drugs for the existing symptoms with malignancies. Introducing new drugs is a very time-consuming and costly process which requires many pre-clinical trials before its use for the commercial purposes. The existing drugs have a huge potential with untapped agents, which are clinically more relevant for disease treatment. More than 200 existing used off patent drugs have shown some evidence for anti-cancer treatment. Since these FDA approved drugs are not in larger number, it is better to repurpose the existing drugs for therapeutic purposes. These drugs can be repurposed for not only cancer treatment but also in rheumatoid arthritis and other disorders. Interestingly multikinase inhibitors are used to interact simultaneously many targets, these drugs can play an important role in drug repurposing for treatment of different diseases.
