Efficacy and Tolerability of Rimegepant for the Prevention of Migraine in Adults With History of Inadequate Response to Oral Preventive Medications

Inclusion Criteria:

1. Migraine attacks present for more than 1 year with the age of onset prior to 50years of age.

2. Migraine attacks, on average, lasting about 4 - 72 hours, if untreated.

3. 4 to 14 migraine days per month, on average, across the 3 months prior to theScreening Visit (month is defined as 28-days for the purpose of this protocol).

4. Less than15 headache days (migraine or non-migraine) per month in each of the 3-months prior to the Screening Visit and throughout the Screening Phase.

5. Subjects must be able to distinguish migraine attacks from tension/clusterheadaches. Prior inadequate response, within 10 years of the Screening Visit, toagents across 2-4 categories of recognized, orally-administered, migraine-preventivemedications where at least one example of prior inadequate response is due to lackof efficacy or prior intolerance (not contraindication).

Exclusion Criteria:

1. History of cluster headaches, basilar migraine (migraine with brainstem aura), orhemiplegic migraine.

2. Current medication overuse headaches.

3. 15 or more headache days (migraine or non-migraine) per month in any of the 3-monthsprior to the Screening Visit or during the first 28- days of the Observation Phase.

4. Inadequate response (due to lack of efficacy, prior intolerance, orcontraindication) to agents across > 4 categories of recognized, orallyadministered, migraine-preventive medications.

5. Active chronic pain syndrome (such as fibromyalgia, chronic pelvic pain, complexregional pain syndrome [CRPS]).

6. Other pain syndromes (including trigeminal neuralgia), dementia, or significantneurological disorders (other than migraine) that, in the Investigator's opinion,interfere with study assessments of safety or efficacy.