IDH1 and central nervous system cancer: In patients with AML, IDH inhibitors act as cellular differentiation agents, not as cytotoxic agents.47 Mutant IDH inhibition in glioma cells has also been demonstrated to promote differentiation.22 The lack of observed changes in ADC in the current study appears to support the hypothesis that IDH inhibition may not have a strong cytotoxic effect in gliomas and that the therapeutic effect of this treatment may be the result of glioma cell differentiation.