AGI-5198

AGI-5198 (IDH-C35) is a potent and selective mutant IDH1^R132H inhibitor with an IC₅₀ of 0.07 μM. In Vitro:Measurements of R-2HG concentrations in pellets of TS603 glioma cells demonstrates dose-dependent inhibition of the mutant IDH1 enzyme by AGI-5198. AGI-5198 does not impair colony formation of two patient-derived glioma lines that express only the wild-type IDH1 allele (TS676 and TS516)^[1]. Cancer cells heterozygous for the IDH1(R132H) mutation exhibits less IDH-mediated production of NADPH, such that after exposure to ionizing radiation (IR), there are higher levels of reactive oxygen species, DNA double-strand breaks, and cell death compared with IDH1 wild-type cells. These effects are reversed by the IDH1(R132H) inhibitor AGI-5198^[2]. In Vivo:AGI-5198 (450 mg/kg, p.o.) causes 50 to 60% growth inhibition of the tumor growth from human glioma xenografts. Tumors from AGI-5198- treated mice show reduced staining with an antibody against the Ki-67 protein. AGI-5198 does not affect the growth of IDH1 wild-type glioma xenografts^[1].