**8. Regulatory and intellectual property issues**

Traditional drug development strategies are costly, failure prone and expensive ventures. Therefore, drug repositioning has recently drawn considerable attention to discover drugs with new therapeutic uses with the goal to bring drugs out at comparatively faster rate for clinical use. Some regulatory issues that are commonly encountered in drug repositioning are described as follows [37, 38]. As per regulatory guidelines, new preclinical and/or clinical trials may be required to be carried out if the available data are not satisfactory and do not comply with the requirements of regulatory agencies such as FDA or EMA. Another important issue is related to patent application and intellectual property rights (IPR). There are no provisions of IP protection of drug discovery by repositioning approach as per the IP and patent laws. For repositioned drugs, IP protection is limited. For repositioning drugs, IP protection is limited. For example, some novel drugtarget disease associations found by repositioning researchers were confirmed by publications or online databases; however, it is difficult to seek IP protection for such associations because of the law. The IP issue prevents some repositioned drugs from entering even into the market [39, 40]. Moreover, some repositioning projects are forced to be abandoned, which is a waste of time, money and lot of efforts. Although many omics data and medical databases have been established, selecting the appropriate approach for repositioning is still a challenge due to the regulatory issues because massive amounts of data may not be valid if not obtained from reliable sources. It is, therefore, necessary that researchers or manufacturers must strictly adhere with standard regulatory guidelines for drug discovery by repositioning approaches [2, 41–43].
