Remote upper arm neuromodulation and combined occipital and trigeminal neuromodulation lead the way as the newest entries to the field, followed by 8 other devices that are now available or are expected to be soon.
The increasing array of prescription medications for the treatment of migraine are welcome additions for patients who suffer from this life-altering condition and the clinicians who treat it; but not all individuals tolerate oral and injectable therapies, and others face the risk of adverse events and medication overuse headache.1 Fortunately, there are a number of devices available to consider, and still others are awaiting approval from the US Food and Drug Administration (FDA).
Two of the most promising devices are remote upper arm neuromodulation (REN) and combined occipital and trigeminal neuromodulation. Here we highlight data from pivotal trials evaluating these 2 treatment options and provide information about other devices worth consideration.
Remote Upper Arm Neuromodulation (REN)
Nerivio was initially authorized by the FDA for the acute treatment of episodic migraine. Available by prescription, the device is administered by the patient at home.2 It stimulates upper arm peripheral nerves, which induces conditioned pain modulation (CPM) that inhibits pain in remote parts of the body. In other words, a descending, endogenous analgesic “pain inhibits pain” mechanism is used.
The initial authorization was based on the results of a randomized, double-blind, sham-controlled, multicenter study involving 252 individuals who were experiencing 2 to 8 migraine headaches per month. Participants were assigned to either a treatment group (n=126), where the device was applied for 30 to 45 minutes within an hour of a migraine attack, or to a sham treatment group (n=126). Investigators looked at migraine pain levels at baseline and at 2 and 48 hours post-treatment, as well as patient-reported most bothersome symptoms. They found that REN provided superior, clinically meaningful relief from migraine pain and the most bothersome symptoms, as follows3:
- 67% of patients in the active treatment group achieved a response at 2 hours vs 39% of individuals in the sham-treatment group
- Pain-free rates at 2 hours in each group were 37% and 18%, respectively
- Most bothersome symptom relief rates at 2 hours were 46% and 22%, respectively
Additionally, pain relief and pain-free responses were sustained at 48 hours. Nearly 40% of active treatment participants still reported pain relief at 48 hours, with pain-free rates at 48 hours in each group of 21% and 8%, respectively. The adverse event rate was low. The most commonly reported adverse event in the active-treatment group was a sensation of warmth (2.4%). Arm pain (1.6%), redness (1.6%), and numbness (0.8%) were also reported in those receiving active treatment.3
In 2020, REN received authorization for the acute treatment of chronic migraine in adults, and the following year authorization was expanded to include adolescent migraine. This development offered a nonpharmacologic treatment approach for migraine sufferers who experience 15 or more headache days per month, which is significant because it reduces the likelihood of medication overuse headache.
Approval for chronic migraine was based on results of an open-label, single-arm, dual-center study involving 38 individuals with chronic migraine. Participants used the device over 4 weeks within 1 hour of a migraine attack. Investigators assessed pain levels at 2 and 24 hours after use; they defined consistency of response as response to at least half of the treatments. The study demonstrated the following4:
- 74% of patients attained pain relief at 2 hours
- 26% were pain free at 2 hours
- 84% achieved sustained pain relief at 24 hours
- 45% achieved sustained pain relief at 24 hours in at least half of their treated attacks
- <2% of participants experienced device-related adverse events
The authors concluded that REN could be used for a series of migraine attacks and is a safe and effective nonpharmacologic approach for individuals who suffer from chronic migraine.4
The findings from these trials are supported by a subsequent trial published earlier this year. This open-label, single-arm study evaluated 91 individuals with chronic migraine who were treated with REN for 4 weeks. Investigators assessed pain levels, associated pain symptoms, and functional disability at baseline as well as at 2 and 24 hours post-treatment. Of the patients in this study5:
- At 2 hours, 59% achieved pain relief, and 21% reported that their pain disappeared
- 73% noted sustained pain relief at 24 hours
- REN was shown to impact nausea, photophobia, and phonophobia favorably, and patients’ functional ability also improved after use
Results from 2 additional trials were also recently released. One study involving 35 adolescents treated with either REN or standard-of-care medications showed REN to be superior with regard to pain freedom (37% vs 9%), consistency of pain freedom (40% vs 9%), pain relief (71% vs 57%), and consistency of pain relief (80% vs 57%).6 The other study included 91 women with a history of menstrual migraine and at least 4 REN treatments. Nearly 75% of patients reported Nerivio to be at least moderately effective, 45% said they were satisfied with the treatment, and all participants noted that it was at least moderately tolerable.7
Combined Occipital and Trigeminal Neuromodulation
In March 2021, the FDA authorized combined occipital and trigeminal neuromodulation (Relivion) for self-treatment of acute migraine.8 It is not yet commercially available, but it will require a prescription. The headset-like device stimulates the occipital and trigeminal nerves by delivering precise modulated pulses simultaneously to 6 branches of the occipital and trigeminal nerves via 3 adaptive output channels. The occipital and trigeminal nerves conduct the signals directly to the brainstem, which maximizes the synergistic effect.9
The results of 2 clinical trials led to FDA approval. These studies have not yet been published in a peer-reviewed journal. The first study, presented at the 61st Annual Scientific Meeting of the American Headache Society in 2019, was a prospective, randomized, double-blind, parallel-group, sham-controlled clinical study involving 55 individuals with chronic or episodic migraine. Participants administered the device for 1 hour soon after migraine onset or administered a sham treatment. Researchers looked at pain score change from baseline to 1 hour post-treatment, as well as pain intensity at baseline and at 1, 2, and 24 hours post-treatment. The study showed that 76% of participants in the active-treatment group experienced headache relief at 2 hours vs 32% in the sham-treatment contingent. No serious adverse events were reported.10 The investigators hypothesized that the positive results observed were a result of the synergistic neuromodulatory effect elicited by concurrent activation of the occipital and trigeminal neural pathways.
Following this study, there was a multi-center, prospective, randomized, double-blind, placebo-controlled clinical trial involving 131 individuals with migraine with or without aura. Participants were assigned to either active treatment or placebo. Investigators assessed reported migraine pain reduction at 2 hours, as well as improvement in most bothersome symptoms after 2 hours, reported pain reduction at 1 hour, and being pain-free at 2 hours. At 2 hours post-treatment11:
- 46% of individuals who were actively treated reached complete freedom from pain vs 12% in the control group
- 75% of active-treatment participants reported being completely free of their most bothersome symptom vs 47% of control patients
- The rates of complete freedom from migraine symptoms were 47% and 11%, respectively
- The rates of pain relief after 2 hours were 60% and 37%, respectively
- No serious adverse events were noted
A systematic review and meta-analysis of 13 studies involving 221 individuals published earlier this year looked at changes in pain scores and response rates to implantable peripheral nerve stimulation for trigeminal neuropathic pain. The response rate to neuromodulation therapy was 61%, the reduction in overall pain scores (2.363) was significant, and a subgroup assessment revealed that the stimulation target (peripheral branch, trigeminal ganglion, or trigeminal nerve root) was responsible for heterogeneity across the studies analyzed. Furthermore, stimulating the trigeminal peripheral branch resulted in better clinical outcomes. The authors noted that their findings reinforce the promise of implantable therapy, particularly for individuals who do not tolerate traditional therapies.12
Looking forward, new data are scheduled to be presented at the International Headache Virtual Congress in September 2021 showing that neuromodulation therapy is highly effective in reducing monthly headache days in individuals who suffer from difficult-to-treat migraine. A larger-scale, double-blind, sham-controlled study is planned to further establish these findings.
Other FDA-Approved Therapies
A number of other devices are available for treatment of migraine headache, including:
- Transcranial magnetic stimulation (TMS). In a randomized trial involving 164 individuals with migraine, 39% of the individuals receiving treatment were pain-free at 2 hours vs 22% of those given sham treatment13
- Noninvasive vagal nerve stimulation (nVNS). This is performed using a handheld device that is controlled by the patient, which preferentially activates afferent A and large B fibers. In a randomized trial involving 243 individuals, pain-free rates at 30, 60, and 120 minutes for patients receiving active treatment were 13%, 21%, and 30%, respectively. Rates for those receiving sham treatment were 4%, 10%, and 20%, respectively.14
- Sumatriptan nasal spray (10 mg) with a permeation enhancer. A randomized phase 2 trial involving 107 individuals found that 44% of participants in the treatment group achieved pain freedom at 2 hours vs 23% who received placebo. The spray appears to work quickly and with fewer adverse events than generic sumatriptan 20 mg nasal spray.15
- Transcutaneous supraorbital nerve stimulation (tSNS). Available without a prescription, there are 3 devices that can treat acute migraine; prevent acute migraine; or both.
Therapies Awaiting FDA Approval
There are several therapeutic options in the pipeline that have not yet been authorized by the FDA.
- Zavegepant (formerly known as vazegepant) nasal spray.16 This third-generation small molecule calcitonin gene-related peptide (CGRP) receptor antagonist has been demonstrated to work as a nasal spray in individuals with migraine. In a phase 1 study, the spray was shown to reach maximal concentration earlier than with other CGRP receptor antagonists.17 A phase 2/3 placebo-controlled trial demonstrated sustained pain freedom from 2 to 48 hours with 5-mg, 10-mg, and 20-mg dosages. The 10-mg and 20-mg doses were statistically superior to placebo on the co-primary endpoints of pain freedom and freedom from most bothersome symptom at 2 hours using a single dose. Sustained pain relief from 2 to 48 hours was seen with the 5-mg and 10-mg dosages18
- Sphenopalatine ganglion (SPG) stimulation. This is a microstimulator that is inserted orally, designed to fit the face, and directly targets SPG. Stimulation is active and controlled by the patient. A randomized, sham-controlled trial evaluated acute pain relief as well as pain freedom and found that those receiving treatment were more than twice as likely to experience pain relief and pain freedom19
- Adhesive dermally applied microneedle system (ADAM). This is a transdermal patch containing microprojections, which can be coated with both large and small molecules. In a randomized trial, 42% of treated participants reported being pain free at 2 hours vs 14% of placebo-treated patients. Rates of freedom from most bothersome symptom were 68% and 43%, respectively20
- Dihydroergotamine (DHE) nasal powder spray and intranasal liquid. Both therapies are awaiting FDA approval. The mucoadhesive powder formulation facilitates rapid drug absorption and is offered in a single-use nasal delivery device. In clinical trials, the spray demonstrated the device’s simplicity, reliability, and ease of use.21 The intranasal liquid is designed to deliver the drug into the vascular-rich upper nasal space. In the phase 3 trial that included 354 patients, 66.3% of patients reported pain relief, 38% of patients reported pain freedom, and 52% had freedom from their most bothersome migraine symptom at 2 hours following their first dose.22