SAN FRANCISCO – Now that noninvasive vagus nerve stimulation using a small handheld device has earned clearance from the Food and Drug Administration for acute treatment of migraine attacks, investigators are pouring over data from the major clinical trials to gain post hoc insight into how to optimize use of the gammaCore device in routine clinical practice.
The answer is to use it early in the course of an attack and use it often, Eric Liebler said at the annual meeting of the American Headache Society.
Bruce Jancin/MDedge News
Eric Liebler
“Our motto here in the U.S. is to get the device and use it as many times as you want during the month. There are no pharmacologic side effects, no drug-drug interactions, and no risk of overusing it that we are aware of at this point. So if you give it to a patient who’s able to say, ‘Wait a second – I don’t feel good, I have premonitory symptoms,’ if they use it, then they’re likely to feel better, with a clinically relevant reduction of at least 1 point when treating a migraine while it’s mild,” according to Mr. Liebler, senior vice president for neurology at electroCore, of Basking Ridge, N.J., which markets the noninvasive vagus nerve stimulation (nVNS) gammaCore device.
The device received FDA clearance for acute treatment of migraine in January 2018 following regulatory approval in the spring of 2017 for treatment of episodic cluster headache.
Mr. Liebler presented key highlights of the recently published pivotal PRESTO trial (Prospective Study of nVNS for the Acute Treatment of Migraine), a randomized, double-blind, multicenter, sham-controlled study of 243 adults under age 50 years who experienced 3-8 migraine attacks per month (Neurology. 2018 Jun 15. doi: 10.1212/WNL.0000000000005857).
“This study provides Class I evidence that, for patients with an episodic migraine, nVNS significantly increases the probability of having mild pain or being pain-free post stimulation,” Mr. Liebler declared.
During the 4-week, double-blind treatment period, 48% of the active nVNS group met the International Headache Society definition of pain relief, which meant at least a 1-point reduction in migraine severity on a 0-3 point pain scale at 120 minutes in at least 50% of treated migraine episodes without using rescue medications. This was a significantly better result than the 32% rate seen in patients in the control group who were given a sham device that emitted a perceptible but ineffective signal.
Similar results were documented during the subsequent 4-week, open-label treatment period, during which the control group was switched over to a functioning gammaCore.
“You can tell your patients they have a reliable chance of having a response more often than not,” according to Mr. Liebler.
What else can physicians tell their migraine patients to expect regarding efficacy? The pain-free responder rate at 120 minutes in PRESTO and other studies is similar to rates reported in meta-analyses of oral triptan therapy but without any drug side effects or limitations on frequency of use. Furthermore, the need for rescue medication at any time during a migraine attack was significantly lower with nVNS than it was with sham treatment, by a margin of 48%-63%.
“If they use this device, they’re often able to save that triptan for when they wake up in the morning and they’re already at a 3 in migraine severity,” he observed.
Also, nVNS is fast-acting: At 30 minutes from onset of pain in the first treated attack, 27% of the nVNS group had experienced pain relief, compared with 19% of controls.
The tolerability profile of the device therapy was outstanding, with no treatment discontinuations in the active treatment arm and only occasional reports of mild transient application site discomfort.
Asked about insurance coverage, Mr. Liebler said broad coverage is coming, but it’s not here yet.
“Insurers don’t really want to pay for anything, and devices confuse them even more than drugs. But we’re getting there because of the quality of the evidence. They were really having a good time telling us we didn’t have any published papers, and now that we’ve given them a class I study published in Neurology, they’ve said they had to review it. CVS will cover it starting Jan. 1,” he continued.
Planning is underway for additional clinical trials of the gammaCore for prevention of episodic migraine, acute treatment of attacks in adolescents, and for use in pregnancy.