In phase II clinical trials of pediatric patients, MEK inhibitors have demonstrated efficacy in pretreated, non- neurofibromatosis type 1 (NF1), recurrent optic pathway and hypothalamic low-grade gliomas, as well as BRAF-mutated or NF1- associated low grade gliomas (73, 74). The gene discussed is NF1; the disease is low grade glioma.