IDO1 and cancer: Nevertheless, multiple Phase I/II clinical studies are currently evaluating the clinical efficacy of the IDO inhibitor Epacadostat (INCB024360) in association with standard therapy, targeted therapy, immunotherapy (cancer vaccines or immune checkpoint blockade) or the combination of these approaches for patients with different types of solid tumors or lymphoma refractory to previous treatments (NCT01961115, NCT03823131, NCT03589651, NCT03532295, NCT03471286, NCT03006302, NCT04463771, NCT03328026 and NCT03322384).