The purpose of this study is to demonstrate the safe use of the PRIMUS system in subjects with chronic migraine. This is a single-center, open label, prospective, early feasibility study to collect initial clinical data on the PRIMUS system for the treatment of chronic migraine.

Main Inclusion Criteria:

• Able and willing to provide informed consent
• Age ≥ 18 years and ≤ 84 years at time of consent
• Documented Chronic Migraine, defined as at least eight migraine days/month, for at least 1 year.
• Developed migraine before the age of 50
• Documented failure of 3 or more other preventive therapies (failure meaning ineffective, provoked unacceptable side-effects or contra-indicated) from which at least 1 of the following 2: CGRP mAbs or Onabotulinumtoxin A
• Have at least 1 headache free day per month
• Stable on preventive migraine drugs and alternative treatment for at least three months prior to enrollment.
• Agree to refrain from starting new preventive migraine drugs or other preventive alternative migraine treatments, from 4 weeks before entering the baseline period throughout the duration of the study.
• MRI available (not older than 4 years prior to study enrollment) or willing to undergo an MRI to exclude structural lesions potentially causing headache
• Able and willing to complete a daily headache eDiary

Main Exclusion Criteria:

• Any other chronic primary or secondary headache disorder, unless they can clearly differentiate them from migraine attacks, based on the quality of pain and associated symptoms.
• Concomitant neuromodulation
• Previous failure to an implantable neuromodulation device for neurovascular headache
• Have an existing Active Implantable Medical Device nearby the implant location (e.g. DBS, cochlear implant, …)
• Metal implants in the skull (e.g. skull plates, seeds) nearby the implant.
• Have a pacemaker of implantable cardioverter defibrillator (ICD)
• Current Opioid Use, defined as one or more opioids on more than 4 days/month for 3 consecutive months.
• Use of botulinum toxin injections in the past 3 months.
• Women of childbearing age who are pregnant, nursing or not using contraception