PF-06840003

PF-06840003 is a highly selective, orally bioavailable small molecule inhibitor of indoleamine 2,3-dioxygenase 1 (IDO1), an enzyme involved in tryptophan catabolism and immune regulation. By inhibiting IDO1, PF-06840003 blocks the conversion of tryptophan to kynurenine, thereby reducing immunosuppressive metabolites in the tumor microenvironment. This action is intended to restore T cell proliferation and function, counteracting tumor-induced immune tolerance. The drug demonstrates good central nervous system penetration and was developed for potential use against brain cancers such as malignant glioma. Preclinical studies showed antitumor activity both as monotherapy and in combination with immune checkpoint inhibitors (e.g., PD-L1 or CTLA4 blockers). Clinical development included phase 1 trials for malignant glioma but has since been discontinued[1][4][5][6][7].

Other names

EOS200271EOS-200271EOS 200271