BETi JQ1 demonstrated significant inhibition of BET activity but limited clinical success [101], as seen with the withdrawal of the Phase II trial for birabresib (MK-8628, OTX015), a selective inhibitor of BRD2/BRD3/BRD4, due to lack of efficacy in IDH-wildtype gliomas. Here, IDH2 is linked to central nervous system cancer.