Mutant IDH1

Class

Small molecule mutant IDH1 inhibitor

Pathway

2-hydroxyglutarate oncometabolite reduction, restoring myeloid differentiation

Isocitrate dehydrogenase 1 (IDH1) is a metabolic enzyme that normally converts isocitrate into alpha-ketoglutarate (α-KG), a molecule used throughout the cell for energy metabolism and as a cofactor for enzymes that regulate DNA and histone methylation. Certain point mutations in IDH1, found recurrently in acute myeloid leukemia and some solid tumors such as glioma, change the enzyme's chemistry so that it produces an abnormal metabolite, D-2-hydroxyglutarate (2-HG), instead of α-KG. 2-HG accumulates to high levels and interferes with enzymes that depend on α-KG, disrupting normal patterns of DNA and histone methylation. In blood-forming cells, this disruption blocks the normal maturation of myeloid progenitors, contributing to leukemia. Small molecules that selectively inhibit the mutant form of IDH1 are designed to suppress 2-HG production without impairing the normal, wild-type enzyme's role in cellular metabolism. By lowering 2-HG, these agents aim to relieve the block on differentiation and allow abnormal progenitor cells to mature into functional blood cells. This mechanism is distinct from cytotoxic chemotherapy in that it targets a specific metabolic consequence of a genetic mutation rather than broadly killing dividing cells, making it relevant wherever IDH1 mutations drive disease biology.