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

The main purpose of this study is to evaulate the efficacy and safety of galcanezumab in participants 6 to 17 years of age for the preventive treatment of episodic migraine. The primary objective is to demonstrate the superiority of galcanezumab versus placebo in the reduction of monthly migraine headache days across the 3-month double-blind treatment period.

The study has two parts which enroll separately from each other such that participants may choose to participate in either but not both: the main study and a study addendum. * The main study includes a 3-month, randomized, double-blind treatment period in which participants receive either galcanezumab or placebo, followed by a 9-month open-label extension in which all participants receive galcanezumab. * The study addendum is a stand-alone study of galcanezumab pharmacokinetics and safety in a group of participants separate from those in the main study. The study addendum includes a 5-month evaluation period after a single injection of galcanezumab, followed by a 9-month open-label extension.