Definition

An orally available inhibitor of mutant form of the isocitrate dehydrogenase type 1 (IDH1; IDH-1; IDH1 [NADP+] soluble), including the substitution mutation at arginine (R) in position 132, IDH1(R132), with potential antineoplastic activity. Upon oral administration, crelosidenib specifically and covalently binds to and modifies a single cysteine (Cys269) in the allosteric binding pocket of mutant forms of IDH1, thereby inactivating IDH1. This inhibits the formation of the oncometabolite 2-hydroxyglutarate (2HG) from alpha-ketoglutarate (a-KG). This depletes 2-HG levels, prevents 2HG-mediated signaling and leads to both an induction of cellular differentiation and an inhibition of cellular proliferation in tumor cells expressing mutant forms of IDH1. In addition, crelosidenib has the ability to cross the blood-brain barrier (BBB). IDH1 mutations, including IDH1(R132) mutations, are highly expressed in certain malignancies, including gliomas; they initiate and drive cancer growth by both blocking cell differentiation and catalyzing the formation of 2HG.