After being informed of the study and potential risks, all patients giving informed consent will go undergo a screening period to determine eligibility for study entry. Patients who meet the eligibility requirements will be given cobimetinib to take by mouth once daily at the same time each day for 21 days and then have 7 days with no treatment. Patients will receive cobimetinib as a tablet (adult) or as a liquid (child).
The purpose of this open-label study is to evaluate the safety and efficacy of cobimetinib in extracranial AVM.