Inclusion criteria:  18 years of age or older with anatomic CCM lesions demonstrated by brain MRI Have symptomatic CCM Have provided written informed consent to participate in the study Have NOT participated in a clinical trial utilizing an investigational agent within 28 days or within 6 half-lives of the investigational drug (whichever is longer) prior to Screening  Exclusion Criteria:  Symptoms deemed by the study Investigator to be caused exclusively by irreversible neuronal damage from prior stroke or neurosurgical instrumentation History of cranial irradiation or surgical/radiosurgical treatment of the primary symptomatic CCM lesion Pregnant or breast feeding Unable or unwilling to participate in MRI assessments (eg, claustrophobia, metal implant, implanted cardiac pacemaker, allergy to gadolinium) Liver dysfunction or active liver disease as defined by baseline serum transaminases >2x upper limit of normal (ULN) Have severely impaired renal function (eGFR <60ml/min) or active renal disease Have had a previous diagnosis of skeletal muscle disorders (myopathy) of any cause or have a baseline creatine kinase level > 5x ULN History of alcohol or substance abuse within 1 year prior to screening Clinically significant laboratory abnormality Have had an intracerebral hemorrhage within 3 months of screening or any brain surgery within 6 months of screening