Background
plexiform neurofibromas, long-bone dysplasia, optic pathway glioma, autosomal dominant neurocutaneous disorder, NF1-related PN tumors, sphenoid wing dysplasia or, NF1, osseous lesions
NEUROFIBROMAS, PLEXIFORM NEUROFIBROMA, NEUROFIBROMATOSIS TYPE 1
Neurofibromatosis type 1 (NF1) is an autosomal dominant neurocutaneous disorder characterized by multiple café au lait spots, neurofibromas, axillary freckling, Lisch nodules, osseous lesions (such as sphenoid wing dysplasia or long-bone dysplasia), and optic pathway glioma [Whilst the clinical presentation and severity of NF1 is diverse, approximately 50% of individuals with NF1 present with plexiform neurofibromas (PNs) [NF1 is caused by a lack of functional neurofibromin. Neurofibromin negatively regulates RAS activity in healthy individuals, but in individuals with NF1, RAS activity is dysregulated [The current treatment strategy for common manifestations of NF1 in adults, such as PN, is surgical resection. As PNs are highly infiltrative, surgical intervention can be challenging and of limited efficacy [Mirdametinib and selumetinib are two orally administered small-molecule MEK1/2 inhibitors that are in clinical development for the treatment of NF1. Mirdametinib given to adult patients with NF1 and progressive PN at a dose of 2 mg/mFCN-159 is an orally available and highly potent selective MEK1/2 inhibitor, and a candidate targeted therapy for NF1-related PN tumors. It has a similar mechanism of action to mirdametinib and selumetinib [A first-in-human study of FCN-159 has recently been conducted in patients with 