Citations

Objective To investigate whether levcromakalim (a K ATP channel opener) induces migraine-like headache in people with persistent post-traumatic headache who had no known history of migraine. Methods In a randomized, double-blind, placebo-controlled, 2-way crossover trial, participants were randomly assigned to receive a 20-minute continuous intravenous infusion of levcromakalim (50 µg/mL) or placebo (isotonic saline) on two separate experimental days with a 1-week wash-out period in between. The primary endpoint was the difference in incidence of migraine-like headache between levcromakalim and placebo during a 12-hour observational period after infusion start. The secondary endpoint was the difference in area under the curve for baseline-corrected median headache intensity scores between levcromakalim and placebo during the 12-hour observational period. Results A total of 21 participants with persistent post-traumatic headache were randomized and completed the trial. During the 12-hour observational period, 12 (57%) of 21 participants reported experiencing migraine-like headache following the levcromakalim infusion, compared with three after placebo ( P = 0.013). Moreover, the baseline-corrected median headache intensity scores were higher following the levcromakalim infusion than after placebo ( P = 0.003). Conclusion Our findings suggest that K ATP channels play an important role in the pathogenesis of migraine-like headache in people with persistent post-traumatic headache. This implies that K ATP channel blockers might represent a promising avenue for drug development. Further research is warranted to explore the potential therapeutic benefits of K ATP channel blockers in managing post-traumatic headache. Trial Registration: ClinicalTrials.gov Identifier: NCT05243953

Abstract Pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38), known for its role in migraine pathogenesis, has been identified as a novel drug target. Given the clinical parallels between post-traumatic headache (PTH) and migraine, we explored the possible role of PACAP-38 in the pathogenesis of PTH. To this end, we conducted a randomized, double-blind, placebo-controlled, two-way crossover trial involving adult participants diagnosed with persistent PTH resulting from mild traumatic brain injury. Participants were randomly assigned to receive a 20-min continuous intravenous infusion of either PACAP-38 (10 pmol/kg/min) or placebo (isotonic saline) on two separate experimental days, with a 1-week washout period in between. The primary outcome was the difference in incidence of migraine-like headache between PACAP-38 and placebo during a 12-h observational period post-infusion. The secondary outcome was the difference in the area under the curve (AUC) for baseline-corrected median headache intensity scores during the same 12-h observational period. Of 49 individuals assessed for eligibility, 21 were enrolled and completed the trial. The participants had a mean age of 35.2 years, and 16 (76%) were female. Most [19 of 21 (90%)] had a migraine-like phenotype. During the 12-h observational period, 20 of 21 (95%) participants developed migraine-like headache after intravenous infusion of PACAP-38, compared with two (10%) participants after placebo (P < 0.001). Furthermore, the baseline-corrected AUC values for median headache intensity scores during the 12-h observational period was higher after PACAP-38 than placebo (P < 0.001). These compelling results demonstrate that PACAP-38 is potent inducer of migraine-like headache in people with persistent PTH. Thus, targeting PACAP-38 signalling might be a promising avenue for the treatment of PTH.

Chronic migraine (CM) is a neurological disease characterized by frequent migraine attacks that prevent affected individuals from performing daily activities of living, significantly diminish quality of life, and increase familial burden. Before onabotulinumtoxinA was approved for CM, there were few treatment options for these seriously disabled patients and none had regulatory approval. The terminology and recognition of CM evolved in parallel with the onabotulinumtoxinA clinical development program. Because there were no globally accepted classification criteria for CM when onabotulinumtoxinA was in development, the patient populations for the trials conducted by Allergan were determined by the Allergan migraine team in collaboration with headache scientists and clinicians. These trials and collaborations ultimately led to improvements in CM classifications. In 2010, onabotulinumtoxinA became the first medication and first biologic approved specifically to prevent headaches in patients with CM. Approval was based on 2 similarly designed phase 3, double-blind, randomized, placebo-controlled, multicenter clinical studies. Both studies showed significantly greater improvements in mean change from baseline in headache-day frequency in patients with CM receiving onabotulinumtoxinA compared with those receiving placebo. The safety and effectiveness of onabotulinumtoxinA have been established globally in >5000 patients with CM with or without medication overuse treated in clinical and observational studies. Benefits also include improvements in quality of life, fewer psychiatric comorbidities, and reduced healthcare resource utilization. Across studies, onabotulinumtoxinA was well tolerated; adverse events tended to be mild or moderate in severity and to decline over subsequent treatment cycles.

This Viewpoint describes the relevance of sex-specific differences in the treatment of migraine, including in evidence from trials of CGRP therapeutics, and the clinical implications for decision-making in practice and trial design.

Abstract Objective Assess the long‐term efficacy and safety of erenumab in patients with chronic migraine with acute medication overuse. Background Overuse of acute medication in patients with chronic migraine has been linked to greater pain intensity and disability and may diminish the effectiveness of preventive therapies. Methods This 52‐week open‐label extension study followed a 12‐week double‐blind placebo‐controlled study in which patients with chronic migraine were randomized 3:2:2 to placebo or once‐monthly erenumab 70 mg or 140 mg. Patients were stratified by region and medication overuse status. Patients received erenumab 70 mg or 140 mg throughout or switched from erenumab 70 to 140 mg (based on protocol amendment to augment safety data at higher dose). Efficacy was assessed in patients with and without medication overuse at parent study baseline. Results Of 609 patients enrolled in the extension study, 252/609 (41.4%) met the criteria for medication overuse at parent study baseline. At Week 52, the mean change in monthly migraine days from parent study baseline was −9.3 (95% confidence interval: −10.4, −8.1 days) in the medication overuse subgroup versus −9.3 (−10.1, −8.5 days) in the non‐medication overuse subgroup (combined erenumab doses); proportion of patients achieving ≥50% reduction in monthly migraine days at Week 52 was 55.9% (90/161; 48.2%, 63.3%) versus 61.3% (136/222; 54.7%, 67.4%), respectively. Among baseline users of acute migraine‐specific medication, the mean change in monthly migraine‐specific medication days at Week 52 was −7.4 (−8.3, −6.4 days) in the medication overuse subgroup versus −5.4 (−6.1, −4.7 days) in the non–medication overuse subgroup. Most patients (197/298; 66.1%) in the medication overuse subgroup transitioned to non‐overuse status by Week 52. Erenumab 140 mg was associated with numerically greater efficacy than erenumab 70 mg across all endpoints. No new safety signals were identified. Conclusion Long‐term erenumab treatment demonstrated sustained efficacy and safety in patients with chronic migraine with and without acute medication overuse.