Background: Drug repurposing has grown significantly in recent years. Research and innovation in
drug repurposing are extremely popular due to its practical and explicit advantages. However, its
adoption into practice is slow because researchers and industries have to face various challenges.
Objective: As this field, there is a lack of a comprehensive platform for systematic identification for
removing development limitations. This paper deals with a comprehensive classification of
challenges in drug repurposing.
Method: Initially, a classification of various existing repurposing models is propounded. Next, the
benefits of drug repurposing are summarized. Further, a categorization for computational drug
repurposing shortcomings is presented. Finally, the methods are evaluated based on their strength to
addressing the drawbacks.
Results: This work can offer a desirable platform for comparing the computational repurposing
methods by measuring the methods in light of these challenges.
Conclusion: A proper comparison could prepare guidance for a genuine understanding of methods.
Accordingly, this comprehension of the methods will help researchers eliminate the barriers thereby
developing and improving methods. Furthermore, in this study, we conclude why despite all the
benefits of drug repurposing, it is not more being done.