Safety and Efficacy of Fremanezumab for Migraine in Adult CADASIL

Inclusion Criteria * Age 18 to 70 years old * English speaking * Diagnosis of CADASIL confirmed by presence of a pathogenic NOTCH3 gene mutation * Diagnosis of migraine for at least 12 months and diagnosis of chronic migraine for at least 28 days according to the International Classification of Headache Disorders * MIDAS score of \>10 points * Ability to provide written informed consent Exclusion Criteria * History of ischemic stroke within 4 weeks of screening assessment * Screening blood pressure \>150 mm Hg * Use of onabotulinum toxin A 4 months prior to trial or other injectable/stimulatory/magnetic method of headache control * Use of opiates or barbiturates 4 days prior to trial * Patients with competing intracerebral pathology (e.g. history of intracerebral hemorrhage, multiple sclerosis) * NYHA Class III or IV congestive heart failure * History of myocardial infarction * History of coronary bypass surgery or coronary stenting * Pregnancy or breastfeeding * Contraindication to undergoing brain MRI per standard clinical practice guidelines * Vulnerable populations, including incarcerated inmates, dementia, and inability to provide consent