Used in cancer immunotherapy research to block the IDO (indoleamine 2,3-dioxygenase) enzyme, which plays a role in suppressing the immune system. By inhibiting IDO, this compound helps enhance the body’s immune response against tumor cells. It is studied for potential use in combination with other immunotherapies to improve treatment outcomes in various cancers. Also used as a tool compound in biochemical assays to understand immune modulation pathways.