Migraine is a common neurological disorder typically characterized by attacks of throbbing, moderate to severe headache, often associated with nausea, vomiting, and sensitivity to light and sound. Migraine is extremely common and disabling in children. The purpose of this study is to evaluate how safe and effective ubrogepant is in the acute treatment of migraine in children and adolescents. Ubrogepant is a drug approved for the acute treatment of migraine in adults. Children and adolescents (aged 6-17 years) with a history of migraine will be enrolled. The study will include 2 cohorts of participants - PK Cohort and Main Study (non-PK cohort). Participants aged 6-11 years in the PK Cohort will receive Dose A or Dose B of Ubrogepant for PK analysis to determine dose selection for the main study. In the main study, after dose selection, children aged 6-11 years will be randomized to receive either low or high dose of Ubrogepant or placebo. There is a 1 in 3 chance that a participant will be assigned to placebo. Adolescents aged 12-17 years will be randomized to receive either low or high dose of Ubrogepant or placebo with a 1 in 3 chance of placebo assignment. For qualifying migraine attacks, participants will receive oral tablets of the double-blind study intervention. There will be an option to take a second dose of double-blind study intervention (identical to initial dose), or rescue medication, at least 2 hours after the initial dose, for headache of moderate/severe intensity. Around 1059 participants will be enrolled in the study in approximately 120 sites in the United States. The study duration will be up to 6 months. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects and completing questionnaires.