We excluded patients who had persistent daily headache,cluster headache, head or neck trauma within the past 6months, possible posttraumatic headache, or primary head-ache other than CM. Patients could not have previously failedto respond to adequate trials of migraine preventives withLevel A or Level B evidence from >3 different medicationclasses (based on the list of such preventives found in theAmerican Academy of Neurology’s evidence-based guide-lines13 or onabotulinumtoxinA or B). Patients could not taketherapeutic antibodies during or within 1 year before thestudy and could not have serious or unstable medical orpsychiatric conditions, history of stroke, or history of sub-stance abuse or dependence in the past year or be at risk foracute cardiovascular events based on history or ECG findings.