Drug repositioning, the identification of novel uses of existing therapies, has become an attractive strategy to accelerate drug development. Recently, knowledge graphs (KGs) have emerged as a powerful representation of interconnected data within the biomedical domain. While biomedical KGs can be used to predict new connections between compounds and diseases, most approaches only state \textit{whether} two nodes are related. Yet, they fail to explain \textit{why} two nodes are related. In this project, we introduce an implementation of the semi-parametric Case-Based Reasoning over subgraphs approach (CBR-SUBG), designed to derive the underlying mechanisms for a drug query by gathering graph patterns of similar entities. We show that our adaptation outperforms existing KG link prediction models on a drug repositioning task. Furthermore, our findings demonstrate that CBR-SUBG strategy can not only rank potential repositioning candidates but also provide interpretable biological paths, leading to more informed decisions.