A Study of Galcanezumab (LY2951742) in Participants 6 to 17 Years of Age With Episodic Migraine

Inclusion Criteria: * Have a diagnosis of migraine with or without aura as defined by the IHS ICHD-3 guidelines (1.1 or 1.2 according to ICHD-3 \[2018\]), with a history of migraine headaches of at least 6 months prior to screening. Exclusion Criteria: * Participants who are taking, or are expected to take, therapeutic antibodies during the course of the study (adalimumab, infliximab, trastuzumab, bevacizumab, etc.). Prior use of therapeutic antibodies is allowed if that use was more than 12 months prior to baseline. * Known hypersensitivity to monoclonal antibodies or other therapeutic proteins, or to galcanezumab or its excipients. * Current use or prior exposure to galcanezumab, another CGRP antibody, or CGRP receptor antibody, including those who have previously completed or withdrawn from this study or any other study investigating a CGRP antibody. * History of IHS ICHD-3 diagnosis of new daily persistent headache, cluster headache or migraine subtypes including hemiplegic (sporadic or familial) migraine and migraine with brainstem aura (previously basilar-type migraine). * History of significant head or neck injury within 6 months prior to screening; or traumatic head injury at any time that is associated with significant change in the quality or frequency of their headaches, including new onset of migraine following traumatic head injury. * Participants with a known history of intracranial tumors or developmental malformations including Chiari malformations.