CB-1158 dihydrochloride

CB-1158 dihydrochloride (INCB01158 dihydrochloride) is a potent and orally active inhibitor of arginase, with IC50s of 86 nM and 296 nM for recombinant human arginase 1 and recombinant human arginase 2, respectively. Immuno-oncology agent[1].

CB-1158 dihydrochloride is a potent and orally-bioavailable inhibitor of arginase, with IC50s of 86 and 296 nM for recombinant human arginase 1 and 2, respectively. CB-1158 inhibits native rginase 1 (Arg1) in human granulocyte, erythrocyte, and hepatocyte lysate with IC50s of 178 nM, 116 nM and 158 nM, respectively, and blocks Arg1 in cancer patient plasma (IC50, 122 nM). CB-1158 also exhibits potent inhibitory activity against arginase in human HepG2, K562 cell lines and primary human hepatocytes with IC50s of 32, 139, 210 μM, respectively. CB-1158 shows no effect on NOS. In addition, CB-1158 is not directly cytotoxic to murine cancer cell lines[1].

CB-1158 (100 mg/kg, p.o., twice per day) increases the number of tumor-infiltrating cytotoxic cells and decreases myeloid cells in mice. CB-1158 in combination with PD-L1 blockade or LY 188011 inhibits tumor growth in mice bearing CT26 cancer cells[1].

[1]. Steggerda SM, et al. Inhibition of arginase by CB-1158 blocks myeloid cell-mediated immune suppression in the tumor microenvironment. J Immunother Cancer. 2017 Dec 19;5(1):101.