electroCore LLC

Clinical Results

gammaCore: Initial Efficacy Suggested in Pilot Studies of Chronic Migraine

Study Design

Randomized, multicenter pilot study of gammaCore for the preEVENTative treatment of chronic migraine (The EVENT Study).


Primary Endpoint

Overview of the EVENT Study Design


Study Design

Adult subjects (18-65) meeting International Classification of Headache Disorders (2nd ed) diagnostic criteria for migraine with or without aura who had experienced ? 15 headache days per month.

A total of 59 patients were randomized to receive either nVNS (n=30) or sham (n=29).

Safety and Tolerability

  • Tolerability profile of nVNS was similar to that of the sham device
  • The long-term tolerability profile of nVNS was favorable, with few AEs considered device related

Clinical Efficacy

Prophylactic use of gammaCore in patients with chronic migraine was associated with reductions in the number of headache days and fewer severe headaches.

In the two month comparative phase, there was a decrease of 1.9 headache days per 28 days with three nVNS treated patients having more than a 50% decrease, and one having a 75% decrease in headache days. No sham control patients achieved a significant reduction.

Mean Change in Headache Days from Run-In Phase Through Open Label Phase By Treatment in the Comparative Phase


Mean Change in Headache Days

During the open label phase, the drop in headache days continued to grow, with patients originally randomized to the active therapy and remaining on therapy through the full 6-month open label phase experiencing a reduction of 8.8 headache days per month from baseline (20.9 headache days) at 8 months.

Percentage of Subjects Who Achieved >50% Treatment Response


Treatment Response %

Approximately 38% of patients who were compliant and adherent to the gammaCore treatment regimen for at least 6 months were considered responders to treatment.


  • Prophylactic use of gammaCore was generally safe and well tolerated.
  • Prophylactic use of nVNS in patients with chronic migraine was associated with greater reductions in mean headache days.
  • Longer treatment duration appears to be associated with increased cumulative clinical benefits such as fewer headache days and an improved treatment response.

Access the full posters presented at the American Headache Society, June 2014:

gammaCore: Efficacy in reducing number of cluster headache attacks

Study Design

A randomized, multicenter study for the PREVention and Acute treatment of chronic cluster headache using gammaCore, versus standard of care (The PREVA Study).


Primary Endpoint

The trial enrolled 97 patients, of which 93 were randomized to participate beyond the initial baseline data collection period. Forty five of the patients were randomly selected to use gammaCore and 48 to the best available standard of care. The baseline data collection period was two weeks, followed by the four week randomized phase. All subjects were permitted to continue on active therapy for an additional four-weeks.

Overview of the PREVA Study Design


Study Design

The primary efficacy endpoint was the reduction in number of cluster headache attacks per week during the last two weeks of the randomized phase versus the baseline period. Additional endpoints included the proportion of subjects with more than 50% reduction in cluster headache attacks per week (response rate).

Clinical Efficacy

gammaCore was found to meet its primary endpoint of statistical significance in reducing the number of cluster headache attacks when compared with the standard of care1.

During weeks three and four following the beginning of therapy, the number of cluster headache attacks per week was reduced by 46.3% in patients treated with nVNS compared with 12.5% (p=0.002) in patients treated with the best available standard of care.

1. A diagnostic and treatment process that a clinician should follow for a certain type of patient, illness, or clinical circumstance.

Full data read out expected September 2014

Learn more about gammaCore’s safety profile.