AGI-5198 (CAS 1355326-35-0) is a selective inhibitor of mutant isocitrate dehydrogenase 1 (IDH1) harboring the R132H substitution Identified via high-throughput screening AGI-5198 blocks mutant IDH1-mediated formation of the oncometabolite R-2-hydroxyglutarate (R-2-HG) in a dose-dependent manner Mechanistically inhibition of mutant IDH1 by AGI-5198 induces expression of differentiation-associated zinc finger and BTB domain-containing protein 16 (ZBTB16 also termed PLZF) decreasing histone H3 lysine 9 trimethylation (H3K9me3) and promoting glioma cell differentiation In experimental glioma models AGI-5198 reduces tumor cell proliferation underscoring its utility for investigating differentiation therapy strategies targeting IDH1-mutant cancers