Study of Oral Atogepant to Assess Adverse Events and Change in Disease Activity in Adult Participants With Menstrual Migraine

Inclusion Criteria:

• History and eDiary confirmation have regular menstrual cycles within the range of 21to 35 days in length (Note: menstrual cycle length is calculated as onset of mensesuntil the day before the next onset of menses).

• History of migraine (with or without aura) according to the InternationalClassification of Headache Disorders, 3rd Edition (ICHD-3) for >= 12 months prior toVisit 1/Screening.

• Migraine onset before age 50 years.

• By history at Visit 1/Screening, participant meets ICHD-3 criteria for puremenstrual migraine with or without aura, or menstrually-related migraine with orwithout aura, i.e., in at least 2 out of 3 cycles, experiences migraine attacksstarting during the PMP (Day -2 to Day +3 relative to menses onset) in the opinionof the investigator.

• Participant records 3 perimenstrual periods (PMP) in the eDiary during the screeningperiod, and in at least 2 of 3 PMPs the participant experiences and records amigraine attack in the eDiary with at least 1 migraine day.

Exclusion Criteria:

• History of an average of 15 or more headache days per month during the 3 monthsprior to Visit 1/Screening per the investigator's judgment, or a current diagnosisof chronic migraine as defined by International Classification of HeadacheDisorders, 3rd Edition (ICHD-3).

• An average of 15 or more headache days per month recorded in the eDiary during thescreening period.

• History of migraine with brainstem aura, hemiplegic migraine, or retinal migraine asdefined by ICHD-3.

• Current diagnosis of new persistent daily headache, trigeminal autonomic cephalalgia (e.g., cluster headache), or painful cranial neuropathy as defined by ICHD-3.

• Required hospital/emergency room treatment for migraine attacks 3 or more timeswithin 6 months prior to Visit 1/Screening.

• Presence of other confounding pain syndromes, confounding psychiatric conditions,dementia, epilepsy, or significant neurological disorders other than migraine perinvestigator judgment.

• Has a condition or situation, which the investigator feels will compromise thesafety of the participant or the quality of the data and renders the subject anunsuitable candidate for the study.