As emphasized by the recent FDA-granted accelerated approval of vorasidenib in low-grade glioma with susceptible IDH1/2 mutations [16], as well as ivosidenib for adult patients with previously treated advanced cholangiocarcinoma with IDH1 mutations [15], epigenetic drugs are becoming increasingly specific for their target enzymes and, thus, their development should follow a precision-medicine approach. This evidence concerns the gene IDH1 and central nervous system cancer.