Erenumab For Treatment of Hemicrania Continua

Inclusion Criteria * Adults over the age of 18-66 * At least a 12 month history of hemicrania continua (unremitting subtype) according to International Classification of Headache Disorders, 3rd Edition (ICHD-3)1 * Previous or current complete response to indomethacin * Stable preventive treatment for at least 2 months and no anticipated need to adjust/add current headache prevention treatment Exclusion Criteria * Nonresponse to a therapeutic dose of indomethacin for hemicrania continua when used for at least 1 week * Pregnant or lactating subjects * Use of barbiturate or opioid \>6 days per month; history of chronic migraine * History of previous trigeminal-autonomic cephalalgia * History within previous 2 months of interventional procedure for headache (occipital or other extracranial nerve block, sphenopalatine ganglion block, cervical facet block, facet rhizotomy) * History of cranial nerve/rhizolysis * Botulinumtoxin injection with previous 4 months * Parenteral infusion of or oral corticosteroid use for more than 3 days within 4 weeks prior to screening phase