Of note, we have begun the compassionate use of the FDA-approved MEK inhibitor trametinib in pediatric bAVM cases and observed slowed disease progression in a handful of patients, and treatment with a BBB-permeable MEKi normalized KRAS-induced changes in the cerebrovasculature and bAVM induction in Slco1c1-CreER;Kraslsl−G12D/+ adult mice [163]. The gene discussed is SLCO1C1; the disease is arteriovenous malformations of the brain.