INH154 is primarily utilized in research settings as a potent and selective inhibitor of the enzyme indoleamine 2,3-dioxygenase 1 (IDO1). This enzyme plays a significant role in immune regulation by modulating tryptophan metabolism, which can influence immune tolerance and tumor progression. By inhibiting IDO1, INH154 is often employed in studies to investigate its potential in cancer immunotherapy, aiming to enhance the immune system's ability to combat tumors. Additionally, it is used in preclinical models to explore its effects on autoimmune diseases and inflammatory conditions, where IDO1 activity is implicated in disease pathology. Its application extends to understanding the broader mechanisms of immune evasion and developing therapeutic strategies targeting the IDO1 pathway.