for people ages 18-75 (full criteria)
at San Francisco, California and other locations
study started
estimated completion
Principal Investigator
Nina Riggins, MD, PhD
Photo of Nina Riggins
Nina Riggins



The purpose of the study is to investigate if the use of gammaCore Sapphire™ device reduces the number of migraines preventatively.

Official Title

A Randomized, Multicenter, Double-blind, Parallel, Sham-controlled Study of Non-invasive Vagus Nerve Stimulation for the Prevention of Migraines. (Premium II)


The study is a prospective randomized, multi-center, double-blind, parallel, sham-controlled study, designed for comparison of two parallel groups, gammaCore®-Sapphire (active treatment) and a sham (inactive) treatment.

The study period will begin with a four-week run-in period, during which there is no investigational treatment. The purpose of the run-in period will be to establish a baseline of the subject's headache/migraine history for longitudinal comparison.

The run-in period will be followed by a 12-week randomized period when the subjects will be randomized (1:1) to either active treatment or sham (inactive) treatment.

Subjects will dose themselves 3 times per day for 12 weeks.


Migraine Disorders Prevention Episodic Chronic gammaCore Sapphire active


For people ages 18-75

Key Inclusion Criteria:

  • Between the ages of 18 and 75 years
  • Been previously diagnosed with migraine (with or without aura), in accordance with the ICHD-3 criteria
  • Experiences between 8 to 20 headaches days per month (during the last 3 months), with at least 5 of them being migraine days
  • Onset of migraine at age 50 years or younger
  • Agrees to refrain from initiating or changing any prophylactic medications for indications other than migraine

Key Exclusion Criteria:

  • Concomitant medical condition that will require oral or injectable steroids during the study
  • Currently on a stable regime of more than 1 migraine preventative therapy
  • Other significant pain problem (e.g., cancer pain, fibromyalgia, other head or facial pain disorder)
  • Known or suspected severe cardiac disease (e.g., symptomatic coronary artery disease, prior myocardial infarction, congestive heart failure)
  • Known or suspected cerebrovascular disease
  • Previous cervical vagotomy
  • Currently implanted with an electrical and/or neurostimulator device
  • Been implanted with metal cervical spine hardware or has a metallic implant near the nVNS stimulation site
  • Known history or suspicion of secondary headache
  • Currently using marijuana (including medical marijuana) or has used marijuana (including medical marijuana) or cannabidiol oil within the last 6 months
  • Currently takes simple analgesics or NSAIDs >15 days per month or triptans, ergots, or combined analgesics >10 days per month for headaches or other body pain
  • Currently takes prescription opioids more than 2 days per month for headaches or body pain
  • Failed an adequate trial (2 months or greater) of at least 3 classes of a drug therapy for migraine prevention
  • Surgery for migraine prevention
  • Undergone nerve block (occipital or other) in the head or neck within the last 3 months
  • Received Botox or CGRP mAb injections within the last 6 months
  • Pregnant or thinking of becoming pregnant during the study period, or of childbearing years and unwilling to use an accepted form of birth control
  • Previously used gammaCore


  • UCSF Headache Center accepting new patients
    San Francisco California 94115 United States
  • Stanford University Medical Center Hoover Pavilion accepting new patients
    Palo Alto California 94304 United States

Lead Scientist at UCSF

  • Nina Riggins, MD, PhD
    Assistant Professor, Neurology. Authored (or co-authored) 6 research publications.


accepting new patients
Start Date
Completion Date
ElectroCore INC
Study Type
Last Updated