Atogepant for Prophylaxis of Migraine in Participants Who Failed Previous Oral Prophylactic Treatments.

* At least a 1-year history of migraine with or without aura consistent with a diagnosis according to the ICHD-3, 2018. * Age of the participant at the time of migraine onset \< 50 years -History of 4 to 14 migraine days per month on average in the 3 months prior to Visit 1 in the investigator's judgment * Female participants willing to minimize the risk of inducing pregnancy for the duration of the clinical study and follow-up period. Male participants willing to minimize the risk of inducing pregnancy for the duration of the clinical study and follow-up period. * 4 to 14 migraine days in the 28-day baseline period per eDiary * Failed oral migraine prophylaxis medications from 2 to 4 medication classes

* Any clinically significant hematologic, endocrine, pulmonary, hepatic, gastrointestinal, or neurologic disease * Participant has any other concurrent pain condition that, in the opinion of the investigator, may significantly impact the current headache disorder * In the opinion of the investigator, confounding psychiatric conditions, dementia, epilepsy, or significant neurological disorders other than migraine * Has ≥ 15 headache days per month on average across the 3 months prior to Visit 1 in the investigator's judgment * Has ≥ 15 headache days in the 28-day baseline period per eDiary * Clinically significant cardiovascular or cerebrovascular disease * Has a history of migraine accompanied by diplopia or decreased level of consciousness or retinal migraine as defined by ICHD-3, 2018 * Has a current diagnosis of chronic migraine, new persistent daily headache, medication overuse headache, trigeminal autonomic cephalgia (eg, cluster headache), or painful cranial neuropathy as defined by ICHD-3, 2018