BLU9931 is primarily used in the field of cancer research, particularly in the study of targeted therapies. It functions as a potent and selective inhibitor of fibroblast growth factor receptor 4 (FGFR4), which is often implicated in the progression of certain types of cancers, such as hepatocellular carcinoma (HCC). By inhibiting FGFR4, BLU9931 helps to block the signaling pathways that promote tumor growth and survival. This makes it a valuable tool in preclinical studies aimed at understanding the role of FGFR4 in cancer biology and in the development of new therapeutic strategies for treating FGFR4-driven cancers. Additionally, its specificity allows researchers to explore the potential of FGFR4 inhibition without significant off-target effects, providing insights into more precise and effective cancer treatments.