HDAC9 and medulloblastoma: Given these preclinical data, PNOC016 (NCT03893487) was designed as both a target validation study (the primary objective) and a preliminary efficacy trial to evaluate drug penetration of the pan-HDAC and PI3K inhibitor fimepinostat for newly diagnosed diffuse intrinsic pontine glioma, recurrent high-grade glioma, and recurrent medulloblastoma.