The purpose of this study to show that zavegepant 10 milligrams given through the nose provides:
* freedom from pain, 2 hours after taking the medicine for the first migraine attack.
* consistent freedom from pain, 2 hours after taking the medicine across 4 separate migraine attacks.
This study is seeking participants who:
* are 18 years of age or older.
* have migraine attacks present for at least 1 year with age onset before 50 years old.
* have migraine attacks, on average, lasting about 4 to 72 hours if not treated.
* have 3 to 8 attacks per month but less than15 headache days per month.
If the participant is fit to take part in the study, the participant will receive either the study medicine zavegepant or placebo. A placebo looks like zavegepant but does not contain active ingredients. The study medicine will be given using nasal spray device containing a single amount of zavegepant or matching placebo.
The participants will be instructed to take the study medicine at home if participants have a migraine headache which reaches moderate or severe pain intensity. The participants are expected to treat up to 4 migraines of moderate to severe intensity.
After taking the study medicine, the participant is not allowed to take any other medications for at least 2 hours after taking the study medicine or placebo. Participant can take other medicines after the 2 hours if the migraine is still present. The participant is expected to record on a paper log all medications taken throughout the study.
The study duration is around 26 weeks. This includes a 28-day screening window, up to 20 weeks of treatment period, and a follow up visit at about 4 weeks after taking the study medicine the last time.
The participant is expected to come into the study center up to 4 times. There will be up to 3 telephone contacts including one after taking the study medicine the first time or Month 1 whichever comes first, at Month 3 if the participant is still in the study, and a safety follow-up.
During the study, the participant is expected to complete two sets of questions in an app on a smartphone. This step is done before and after taking the study medicine. The participants must rate:
* Pain symptoms
* How the participants are feeling
* General well-being