Cluster Headache Treatment With Rimegepant

Inclusion Criteria: * Having a diagnosis of recurrent cluster headaches, as described by ICHD-3 (International Classification of Headache Disorders-3): * Severe or very severe unilateral orbital, supraorbital and/or temporal pain lasting 15-180 minutes, when untreated. * Headache is accompanied by at least one of the following: * Ipsilateral conjunctival injection and/or lacrimation; * Ipsilateral nasal congestion and/or rhinorrhea; * Ipsilateral eyelid edema; * Ipsilateral forehead and facial sweating; * Ipsilateral miosis and/or ptosis; * A sense of restlessness or agitation. * Headache attacks occur at a frequency between every other day and 8 per day. * Headaches are not attributed to another disorder. * Subjects able to distinguish cluster headache attacks from other headache disorders, such as migraine. * Subjects on prophylactic headache medicines other than verapamil will be permitted to remain on these with possible headache-prophylactic effects if the dose is stable for at least 2 months (onabotulinumtoxinA injections stable for 6 months) prior to the screening visit and the dose is not expected to change during the course of the study. * Prior MR (magnetic resonance) imaging of head (CT if MRI contraindicated) performed after the onset of headaches. * Subjects agree to refrain from starting a new prophylactic cluster headache medicine, including steroids and nerve blocks, during the course of the study. * Subjects are required to …