Enasidenib mesylate is primarily used in the treatment of relapsed or refractory acute myeloid leukemia (AML) with an IDH2 mutation. It works by inhibiting the mutated IDH2 enzyme, thereby reducing the production of the oncometabolite 2-hydroxyglutarate (2-HG), which helps to restore normal cell differentiation and reduce the proliferation of cancerous cells. This targeted therapy offers a treatment option for patients who may not respond well to conventional chemotherapy, improving survival rates and quality of life. It is administered orally, making it a convenient option for outpatient care. Ongoing research is exploring its potential in other cancers with IDH2 mutations, expanding its therapeutic applications.