['chronic migraine']
['galcanezumab', 'placebo']

        Inclusion Criteria:

          -  Have a diagnosis of chronic migraine as defined by International Headache Society
             (IHS) International Classification of Headache Disorders (ICHD)-3 beta guidelines
             (1.3) (ICHD-3 2013), with a history of migraine headaches of at least 1 year prior to
             screening, and migraine onset prior to age 50.

        Exclusion Criteria:

          -  Are currently enrolled in or have participated within the last 30 days or within 5
             half-lives (whichever is longer) in a clinical trial involving an investigational
             product.

          -  Current use or prior exposure to galcanezumab or another calcitonin gene-related
             peptide (CGRP) antibody.

          -  Known hypersensitivity to multiple drugs, monoclonal antibodies or other therapeutic
             proteins, or to galcanezumab.

          -  History of persistent daily headache, cluster headache or migraine subtypes including
             hemiplegic (sporadic or familial) migraine, ophthalmoplegic migraine, and migraine
             with brainstem aura (basilar-type migraine) defined by IHS ICHD-3 beta.
      