This study is testing how well Xeomin, a type of medicine, works in preventing chronic migraines, which are severe headaches that happen often. Participants will get Xeomin or a Placebo (a fake treatment) through shots in the head and neck. The goal is to see if Xeomin reduces the number of migraine days each month compared to the Placebo.

The trial lasts about a year, with participants attending 14 visits. Four visits are in person for treatment, and the other 10 are done by phone or video. To join, you need to have migraines for at least a year and be able to tell migraines from other headaches. You should have had 15 headache days and 8 migraine days each month before the study. Some types of headaches like tension-type are allowed, but others like hemiplegic migraines are not.

• Duration: Around 52 to 55 weeks with visits every 4 weeks.
• Treatment: Four Xeomin or Placebo injections spaced 12 weeks apart.
• Eligibility: Must have frequent migraines; certain headache types are excluded.