Dodick, David W.

Background The sphenopalatine ganglion (SPG) has previously been targeted in trigeminal neuralgia (TN), but its role in this condition has not been established. Objective To investigate the safety of injecting onabotulinumtoxinA (BTA) toward the SPG using the MultiGuide ® in 10 patients with refractory classical TN, and collect preliminary efficacy data. Methods Twenty‐five international units (IU) of BTA were injected toward the SPG in a prospective, open‐label study in 10 patients with refractory classical TN. All patients were recruited and treated on an out‐patient basis at St. Olav's University Hospital in Trondheim (Norway). Primary outcome: adverse events (AEs). Primary efficacy outcome: number of TN attacks at weeks 5‐8 after injection compared to baseline. A treatment responder was predefined as at least 50% reduction in the median number of attacks per day between baseline and weeks 5‐8. Other efficacy outcomes were intensity of attacks (numeric rating scale, 0 to 10) and functional level (1 to 4; 1 best and 4 worst) at weeks 5‐8 after injection compared to baseline. Percentage of the day with concomitant persistent pain was registered at baseline and at weeks 1‐4, 6, 8, and 12 after injection. Patient global impression of change (PGIC) was ascertained at month 3. Results For the primary endpoint, we analyzed data for all 10 patients. For efficacy outcomes we analyzed data for 9 patients (1 patient violated protocol). We registered 13 AEs, none of which were serious. The median number of TN attacks during the 4‐week baseline and weeks 5‐8 after injection was 5.5 (range: 1.0‐51.5) and 5 (range: 0‐225.0), respectively ( P = .401). Four patients were treatment responders. The median intensity of attacks at baseline and weeks 5‐8 after injection was 6 (range: 3.0‐8.5) and 3 (range: 0.0‐9.0) respectively ( P = .024). The median functional level at baseline was 2 (range: 1.0‐3.3) and at month 2, 1 (range 1.0‐4.0; P = .750). Median percentage of the day with concomitant persistent pain was 75% (minimum 37.5%, maximum 100%) at baseline and 18.75% (minimum 0%, maximum 100%) at week 8 ( P = .023). Conclusions Injection of BTA toward the SPG using the MultiGuide ® in patients with TN appears to be safe and well tolerated. This study was negative for the main efficacy endpoint (reduction in the number of attacks from baseline to weeks 5‐8). Further studies examining the role of the SPG in TN are necessary.

Aim Evaluation of cannabinoid receptor agonists in a preclinical model of medication overuse headache. Methods Female Sprague Dawley rats received graded intraperitoneal doses of WIN55,212-2 or Δ-9-tetrahydrocannabinol (Δ-9-THC). Antinociception (tail-flick test), catalepsy and hypomotility (open field test) and impairment of motor function (rotarod test) were assessed to establish effective dosing. Rats were then treated twice daily with equianalgesic doses of WIN55,212-2 or Δ-9-THC, or vehicle, for 7 days and cutaneous tactile sensory thresholds were evaluated during and three weeks following drug discontinuation. Rats then received a one-hour period of bright light stress (BLS) on two consecutive days and tactile sensory thresholds were re-assessed. Results WIN55,212-2 and Δ-9-THC produced antinociception as well as hypomotility, catalepsy and motor impairment. Repeated administration of WIN55,212-2 and Δ-9-THC induced generalized periorbital and hindpaw allodynia that resolved within 3 weeks after discontinuation of drug. Two episodes of BLS produced delayed and long-lasting periorbital and hindpaw allodynia selectively in rats previously treated with WIN55,212-2, and Δ-9-THC. Interpretation Cannabinoid receptor agonists including Δ-9-THC produce a state of latent sensitization characterized by increased sensitivity to stress, a presumed migraine trigger. Overuse of cannabinoids including cannabis may increase the risk of medication overuse headache in vulnerable individuals.

Background Calcitonin gene-related peptide plays an important role in migraine pathophysiology. We evaluated eptinezumab, an intravenous (IV) anti-calcitonin gene-related peptide monoclonal antibody, for the prevention of chronic migraine. Objective To determine the safety, tolerability, and effectiveness of four dose levels of eptinezumab and to inform the phase 3 development program. Methods This was a phase 2b, parallel-group, double-blind, randomized, placebo-controlled, dose-ranging clinical trial. Men and women (N = 616) aged 18–55 years were included if they had a diagnosis of chronic migraine, with onset at age ≤35 years and history of chronic migraine ≥1 year. During the 28-day screening period, patients must have had ≥15 headache days, including ≥8 migraine days, with ≥5 migraine attacks as recorded in the electronic diary. Patients were assigned in a 1:1:1:1:1 ratio to eptinezumab 300, 100, 30, 10 mg or placebo, administered as a single IV infusion. The primary endpoint was the percentage of patients with a ≥75% decrease in monthly migraine days over weeks 1–12 compared with the 28-day screening period. Results The ≥75% migraine responder rates over weeks 1–12 for eptinezumab 300, 100, 30, and 10 mg were 33.3%, 31.4%, 28.2%, and 26.8%, respectively, versus 20.7% for placebo ( p = 0.033, 0.072, 0.201, 0.294 vs. placebo). Secondary efficacy endpoints (e.g. ≥50% responder rate, change from baseline in frequency of migraine/headache days, and percentage of severe migraines) had results favoring the three higher eptinezumab doses versus placebo. Eptinezumab was well tolerated and adverse event rates were similar to placebo. Conclusions The results of this trial demonstrate that eptinezumab appears effective and well-tolerated for the preventive treatment of chronic migraine and justifies the conduct of pivotal phase 3 trials for migraine prevention. Trial Registration ClinicalTrials.gov identifier: NCT02275117.

Background Previously published three-month placebo-controlled and one-year open-label clinical trial data have provided information on the efficacy and safety of erenumab. Methods Interim analysis was undertaken from an ongoing five-year open-label treatment phase after all patients completed three years in the open-label treatment phase or discontinued the study. Adult patients with episodic migraine enrolled in the open-label treatment phase initially received 70 mg erenumab monthly. A protocol amendment increased the dosage to 140 mg monthly to assess long-term safety of the higher dose. Safety and tolerability were assessed by monitoring adverse events, electrocardiograms, laboratory assessments, and vital signs. Results Of 383 patients enrolled in the open-label treatment phase, at data cutoff 235 (61.3%) remained in the study, all received 140 mg for ≥1 year. Median (Q1, Q3) exposure (70 or 140 mg) for all patients enrolled was 3.2 (1.3, 3.4) years. The most frequent adverse events (≥4.0/100 patient-years) were reported as viral upper respiratory tract infection, sinusitis, influenza, and back pain. Exposure-adjusted serious adverse event rates were 4.2/100 patient-years. There was no increase in cardiovascular events over time. Conclusions In this long-term study of a CGRP-receptor antibody, erenumab was found to be safe and well-tolerated with a spectrum and rate of adverse events consistent with shorter-term placebo-controlled studies. Trial registration ClinicalTrials.gov NCT01952574

Background: The otic ganglion (OG) is a cranial parasympathetic ganglion located in the infratemporal fossa under the foramen ovale (FO) and adjacent to the medial part of the mandibular nerve. Parasympathetic innervation of intracranial vessels from the OG has been shown both in animal and human models and evidence suggests that the OG plays an important role in the cranial vasomotor response. We review the evidence that positions the OG as a viable target for headache disorders. The OG is a small structure and not detectable on medical imaging. The FO is easily identifiable on CT scans and the mandibular nerve on MRI, hence, the position of the OG may be predicted if the mean distance from the FO is known. Objective: The objective is to describe the average distance between the FO and the OG in a sample of 18 infratemporal fossae from 21 cadavers. Methods: A total of 21 high definition photographs of 21 infratemporal fossae from 18 cadavers were analyzed. The distance between the inferior edge of the medial part of the FO to the OG was measured. Results: Four photographs of infratemporal fossae of four cadavers were excluded due to the inability to localize the inferior edge of the FO. A total of 15 infratemporal fossae from 17 cadavers were measured. The mean distance from the FO to the OG was 4.5 mm (SD 1.7), range 2.1–7.7 mm. Conclusions: We have described the average distance from the OG to an easily identifiable anatomical landmark that is visible in CT scans, the FO. This anatomical study may aid in the development of strategies to localize the OG in order to explore its role as a therapeutic target for headache disorders.

Background The Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials demonstrated efficacy/tolerability of onabotulinumtoxinA for headache prevention in adults with chronic migraine. This post hoc analysis assessed time of onset of onabotulinumtoxinA after the first treatment in total and responder populations and consistency weekly through five treatment cycles. Methods In the 24-week, double-blind, placebo-controlled phase of PREEMPT, individuals were randomized 1:1 to onabotulinumtoxinA (155-195 U) or placebo every 12 weeks for two cycles. The primary pooled efficacy variable was change in headache days per 28 days at week 24. We assessed change in headache and migraine/probable migraine (hereafter migraine) days/week compared with baseline week 4. Results Baseline mean (SD) headache days/week (week 4 of baseline) for onabotulinumtoxinA (n = 688) and placebo (n = 696) were similar (4.8 [1.6] vs. 4.8 [1.6] days/week, respectively), as were migraine days/week (4.6 [1.7] vs. 4.6 [1.7] days/week). The effect of onabotulinumtoxinA on change in headache and migraine days/week was significantly greater than placebo at week 1, persisting from week 3 after the first treatment (−1.6 [2.2] vs. −1.1 [2.2] headache days/week [ p < 0.001] and −1.6 [2.2] vs. −1.1 [2.2] migraine days/week [ p < 0.001]). Headache and migraine days decreased in onabotulinumtoxinA responders beginning 1 week after treatment 1. Conclusions Treatment with onabotulinumtoxinA is associated with significant reductions in headache and migraine days/week at week 1, persisting after week 3, compared with placebo. Combined with earlier reports showing onabotulinumtoxinA treatment results in a persistent and progressive reduction in headache days over 56 weeks, it is suggested peak benefit may require multiple treatments. Trial registration number ClinicalTrials.gov: NCT00156910 and NCT00168428.

Objective To assess the efficacy and safety of a remote electrical neuromodulation (REN) device for the acute treatment of migraine. Background There is a significant unmet need for novel effective well‐tolerated acute migraine treatments. REN is a novel acute migraine treatment that stimulates upper arm peripheral nerves to induce conditioned pain modulation – an endogenous analgesic mechanism in which conditioning stimulation inhibits pain in remote body regions. A recent pilot study showed that REN can significantly reduce headache. We have conducted a randomized, double‐blind, sham‐controlled study to further evaluate the efficacy and safety of REN for the acute treatment of migraine. Methods This was a randomized, double‐blind, sham‐controlled, multicenter study conducted at 7 sites in the United States and 5 sites in Israel. Two hundred and fifty‐two adults meeting the International Classification of Headache Disorders criteria for migraine with 2‐8 migraine headaches per month were randomized in a 1:1 ratio to active or sham stimulation. A smartphone‐controlled wireless device was applied for 30‐45 minutes on the upper arm within 1 hour of attack onset; electrical stimulation was at a perceptible but non‐painful intensity level. Migraine pain levels were recorded at baseline, 2, and 48 hours post‐treatment. Most bothersome symptoms (MBS) were also recorded. The primary efficacy endpoint was the proportion of participants achieving pain relief at 2 hours post‐treatment (improvement from severe or moderate pain to mild or none, or from mild pain to none). Relief of MBS and pain‐free at 2 hours were key secondary endpoints. Results Active stimulation was more effective than sham stimulation in achieving pain relief (66.7% [66/99] vs 38.8% [40/103]; therapeutic gain of 27.9% [CI 95% , 15.6‐40.2]; P < .0001), pain‐free (37.4% vs 18.4%, P = .003), and MBS relief (46.3% vs 22.2%, P = .0008) at 2 hours post‐treatment. The pain relief and pain‐free superiority of the active treatment was sustained 48 hours post‐treatment. The incidence of device‐related adverse events was low and similar between treatment groups (4.8% [6/126] vs 2.4% [3/126], P = .499). Conclusions REN provides superior clinically meaningful relief of migraine pain and MBS compared to placebo, offering a safe and effective non‐pharmacological alternative for acute migraine treatment.

The quality of clinical trials is an essential part of the evidence base for the treatment of headache disorders. In 1991, the International Headache Society Clinical Trials Standing Committee developed and published the first edition of the Guidelines for controlled trials of drugs in migraine. Scientific and clinical developments in headache medicine led to second and third editions in 2000 and 2012, respectively. The current, fourth edition of the Guidelines retains the structure and much content from previous editions. However, it also incorporates evidence from clinical trials published after the third edition as well as feedback from meetings with regulators, pharmaceutical and device manufacturers, and patient associations. Its final form reflects the collective expertise and judgement of the Committee. These updated recommendations and commentary are intended to meet the Society's continuing objective of providing a contemporary, standardized, and evidence-based approach to the conduct and reporting of randomised controlled trials for the acute treatment of migraine attacks.