Anti-migraine Calcitonin Gene-Related Peptide Receptor Antagonists Worsen Cerebral Ischemic Outcome in Mice

[Acute Therapy of Migraine: What is new?]

The landscape of acute migraine medication has changed fundamentally in recent years. It has been a gradual, often unnoticed process characterized less by spectacular introduction of new substances than by changes in patients' access to medications and individualized selection of treatment adapted to the patients' needs. Four triptans are now available over-the-counter in Germany which has a major influence on self-medication. The main new introduction was the 5HT1F-agonist lasmiditan as an alternative to triptans.

Cortical Hyperperfusion on MRI Arterial Spin-Labeling during the Interictal Period of Patients with Migraine Headache

BACKGROUND AND PURPOSE

Concentrations of calcitonin gene-related peptide, a neuropeptide and potent endogenous vasodilator, are reportedly higher in patients with migraine than in healthy subjects, both during and between migraine attacks, reflecting ongoing activation of the trigeminal nervous system. In this prospective study, we measured CBF during the interictal period of patients with migraine after considering insomnia and depression and examined the effects of ongoing activation of the trigeminal nervous system, including during the interictal period, on CBF.

MATERIALS AND METHODS

In a total of 242 patient with migraine (age range, 18-75 years), CBF was measured by MR imaging arterial spin-labeling during the interictal period and was compared with results from 26 healthy volunteers younger than 45 years of age as control subjects (age range, 22-45 years). Cortical hyperperfusion was defined as identification of ≥2 cerebral cortical regions with regional CBF values at least 2 SDs above the mean regional CBF in control subjects.

RESULTS

The overall frequency of cortical hyperperfusion was significantly higher in patients with migraine (115 of 242, 48%) than in control subjects (1 of 26, 4%). Multivariable analysis revealed the 18- to 40-year age group and patients with migraine without insomnia as significant positive clinical factors associated with cortical hyperperfusion. Among patients with migraine without insomnia, the frequency of cortical hyperperfusion was >92% (89 of 97). One-way ANOVA showed that in all ROIs of the cortex, regional CBF was significantly higher in patients with migraine without insomnia than in patients with migraine with insomnia or control subjects. In patients with migraine without insomnia, cortical hyperperfusion findings showed a sensitivity of 0.918 and a specificity of 0.962 for migraine in the interictal period, representing excellent accuracy. In contrast, among patients with migraine with insomnia, sensitivity was only 0.179 but specificity was 0.962.

CONCLUSIONS

Patients with migraine without insomnia may have cortical hyperperfusion during the interictal period; however, the findings of the present study need to be prospectively validated on a larger scale before clinical applicability can be considered.

Blood pressure monitoring in elderly migraineurs starting an anti-CGRP monoclonal antibody: a real-world prospective study

BACKGROUND

While monoclonal antibodies (mAbs) targeting the CGRP pathway have revolutionized migraine management due to their improved tolerance and adherence, concerns remain about their potential impact on blood pressure (BP), especially in older patients, due to CGRP-mediated vasodilation blockade. Given the growing use of these therapies in older populations, assessing their cardiovascular (CV) safety is of paramount importance.

METHODS

This multicentric observational prospective study focused on migraine sufferers aged ≥ 60 who began erenumab, galcanezumab, or fremanezumab for prevention. Baseline, three-month, and twelve-month BP measurements were collected. Changes in antihypertensive medication and "Newly or Worsened Hypertensive" patients (NWHP) were assessed.

RESULTS

Among 155 patients receiving anti-CGRP mAbs (40 Erenumab, 47 Galcanezumab, 68 Fremanezumab), 42.5% had hypertension history and 39% were on antihypertensive treatment. No significant systolic or diastolic BP changes occurred at any time point compared to baseline (all p > 0.05), with no differences between the three groups. After one year, 20/155 (12.9%) patients were considered NWHP; 11/20 had prior hypertension, and 5/11 adjusted antihypertensive therapy. Among 9/20 newly hypertensive patients, 5/9 had a single measurement above the normal threshold with no requirement for new pharmacological therapy. A higher baseline BP value was associated with increased BP (p = 0.002).

CONCLUSIONS

The study concludes that treatment with anti-CGRP mAbs over one year does not significantly affect BP in patients aged ≥ 60, nor does it increase the incidence of hypertension compared to general population trends. Nonetheless, continuous monitoring and further long-term studies are necessary to fullya scertain the cardiovascular safety of these medications in the elderly.

Safety considerations in the treatment with anti-CGRP(R) monoclonal antibodies in patients with migraine

Background

Anti-CGRP-(receptor-)monoclonal antibodies (anti-CGRP(R)-mAbs) represent a novel class of drugs for migraine treatment, but their long-term cerebrovascular and cardiovascular (CV) safety warrants further examination.

Methods

In this observational cohort study we assessed the CV safety for erenumab and fremanezumab in a real-world setting during a follow-up period of at least 1 year. Patients with hypertension or CV history were excluded. We conducted ECGs and collected clinical data at treatment initiation and thereafter every 3 months, including liver and kidney function, lipid-, electrolyte-and glucose levels.

Results

Among patients receiving erenumab (n = 101) or fremanezumab (n = 92), 3.1% (6/193) developed abnormal ECGs or CV adverse events. Of these, three (1.6%) experienced moderate to severe CV adverse events (cerebellar stroke, spontaneous coronary artery dissection, and pericarditis) and discontinued treatment. The remaining three (1.6%) developed non-threatening ECG abnormalities without physical complaints. No significant changes were observed in liver and kidney function, lipid-, electrolyte-, or glucose levels.

Discussion

We observed CV events in 1.6% of patients with 1.5-year follow-up of anti-CGRP(R)-mAbs treatment. We advise awareness regarding CV events in patients with migraine undergoing CGRP-targeted treatment, not as a confirmation of increased risk but as a proactive measure to address potential multifactorial influences.

New migraine drugs: A critical appraisal of the reason why the majority of migraine patients do not receive an adequate medication

The last three decades have produced several novel and efficient medications to treat migraine attacks and reduce attack frequency. Additionally, promising approaches for the development of acute therapy and migraine prophylaxis continue to be pursued. At the same time as we witness the development of better and more efficient medications with continuously fewer side effects, we also realise that the high cost of such therapies means that only a minority of migraine patients who could benefit from these medications can afford them. Furthermore, information on cost-effectiveness is still lacking. Here, we compare availiable data, highlight open questions and suggest trials to close knowledge gaps. With good reason, our medicine is evidence-based. However, if this evidence is not collected, our decisions will continue to be based on marketing and assumptions. At the moment, we are not doing justice to our patients.

Pharmacology of erenumab in human isolated coronary and meningeal arteries: Additional effect of gepants on top of a maximum effect of erenumab

BACKGROUND AND PURPOSE

Multiple drugs targeting the calcitonin gene-related peptide (CGRP) receptor have been developed for migraine treatment. Here, the effect of the monoclonal antibody erenumab on CGRP-induced vasorelaxation was investigated in human isolated blood vessels, as well as the effect of combining erenumab with the small molecule drugs, namely rimegepant, olcegepant, or sumatriptan.

EXPERIMENTAL APPROACH

Concentration-response curves to CGRP, adrenomedullin or pramlintide were constructed in human coronary artery (HCA) and human middle meningeal artery (HMMA) segments, incubated with or without erenumab and/or olcegepant. pA2 or pKb values were calculated to determine the potency of erenumab in both tissues. To study whether acutely acting antimigraine drugs exerted additional CGRP-blocking effects on top of erenumab, HCA segments were incubated with a maximally effective concentration of erenumab (3 μM), precontracted with KCl and exposed to CGRP, followed by rimegepant, olcegepant, or sumatriptan in increasing concentrations.

KEY RESULTS

Erenumab shifted the concentration-response curve to CGRP in both vascular tissues. However, in HCA, the Schild plot slope was significantly smaller than unity, whereas this was not the case in HMMA, indicating different CGRP receptor mechanisms in these tissues. In HCA, rimegepant, olcegepant and sumatriptan exerted additional effects on CGRP on top of a maximal effect of erenumab.

CONCLUSIONS AND IMPLICATIONS

Gepants have additional effects on top of erenumab for CGRP-induced relaxation and could be effective in treating migraine attacks in patients already using erenumab as prophylaxis.

Consensus-Based Recommendations on the Use of CGRP-Based Therapies for Migraine Prevention in the UAE

INTRODUCTION

Migraine is a common debilitating neurological disorder affecting a large proportion of the general population. Calcitonin gene-related peptide (CGRP), a 37-amino acid neuropeptide, plays a key role in the pathophysiology of migraine, and the development of therapies targeting the anti-CGRP pathway has revolutionized the field of migraine treatment.

METHODS

An expert task force of neurologists in the United Arab Emirates (UAE) developed and critically assessed recommendations on the use of CGRP-based therapies in migraine treatment and management in the UAE, based on available published literature. A consensus was reached for each statement by means of an open-voting process, based on a predefined agreement level of at least 60%.

RESULTS

The consensus recommendations advocate the need for guidelines for the appropriate use of CGRP-based therapies by defining patient cohorts and appropriate monitoring of therapeutic response as well as standardizing the initiation, assessment, and cessation of treatment. The consensus recommendations were primarily formulated on the basis of international studies, because of the limited availability of regional and local data. As such, they may also act as guidelines for global healthcare providers.

CONCLUSIONS

These are the first consensus recommendations for the UAE that address the use of CGRP-based therapies in the treatment and management of migraine, integrating both clinical evidence and medical expertise to enhance clinical judgment and decision-making.

Managing and Preventing Migraine in the Emergency Department: A Review

Migraine is a leading cause of disability worldwide, and acute migraine attacks are a common reason for patients to seek care in the emergency department (ED). There have been recent advancements in the care of patients with migraine, specifically emerging evidence for nerve blocks and new pharmacological classes of medications like gepants and ditans. This article serves as a comprehensive review of migraine in the ED, including diagnosis and management of acute complications of migraine (eg, status migrainosus, migrainous infarct, persistent aura without infarction, and aura-triggered seizure) and use of evidence-based migraine-specific treatments in the ED. It highlights the role of migraine preventive medications and provides a framework for emergency physicians to prescribe them to eligible patients. Finally, it evaluates the evidence for nerve blocks in the treatment of migraine and introduces the possible role of gepants and ditans in the care of patients with migraine in the ED.

Post-stroke Headache

PURPOSE OF REVIEW

Stroke is a major health concern and a leading cause of long-term disability. Persistent post-stroke headache (PPSH) is a common complication of stroke yet little is known about its specific characteristics or optimal management. The purpose of this review is to discuss the epidemiology, presentation, and hypothesized pathophysiology of PPSH. Acute and preventive treatment options, as well as specific concerns regarding triptans and the newer CGRP antagonists, will be discussed in detail as well.

RECENT FINDINGS

The 2018 International Classification of Headache Disorders, 3rd edition (ICHD-3) was the first headache diagnostic manual to include criteria for PPSH and defines this disorder as an acute headache that develops in close temporal relation to stroke and persists beyond 3 months. Recent literature estimates the prevalence of PPSH to be somewhere between 1 and 23% of patients post-stroke. Presentation is variable, but most often mimics tension-type headache. There are no evidence-based guidelines on the optimal treatment of PPSH. PPSH is a common but poorly understood complication of stroke. Given the significant disability burden that PPSH carries, the epidemiology and pathophysiology of PPSH, as well as the efficacy and safety of potential treatment options, warrant further investigation.

Reversible Cerebral Vasoconstriction Syndrome Exacerbation After Calcitonin Gene-Related Peptide Inhibitor Administration

Background: Reversible cerebral vasoconstriction syndrome (RCVS) is a non-inflammatory vasculopathy. While most patients have good clinical outcomes, RCVS can be associated with severe brain injury from ischemic stroke, subarachnoid, and intracerebral hemorrhage. Purpose: A number of vasoactive medications have been implicated in RCVS, including triptans, amphetamines, antidepressants, and decongestants. Given the role of CGRP in modulating cerebral vasodilation, the possibility of CGRP inhibitors contributing to RCVS has been raised. Research Design: Case report at the University of Pennsylvania. Study Sample: Patient at the University of Pennsylvania. Results: We report a patient with RCVS in which severe exacerbation resulting in multifocal ischemic stroke occurred following administration of the calcitonin gene-related peptide (CGRP) inhibitor fremanezumab. Conclusions: It is unclear whether fremanezumab played a role in this patient's case, but CGRP-inhibitor use should be considered as a potential precipiating factor.

Migraine in older adults

Migraine is an evolving, and sometimes lifelong disorder. The prevalence of episodic migraine peaks among individuals aged in their late 30s, implying a tendency for the disorder to remit with increasing age thereafter, whereas chronic migraine is more likely to persist into later life. Diagnosis and treatment of migraine in older adults, defined as individuals aged 60 years or older, is rendered more complex by increasing probabilities of atypical clinical features and comorbidities, with patients' comorbidities sometimes limiting their therapeutic options. However, the changing clinical presentation of migraine over an individual's lifespan is not well characterised. The neurobiological basis of remission in older adults remains unclear, although vascular, neuronal, and hormonal changes are likely to be involved. Long-term longitudinal studies of individuals with migraine would be particularly informative, with the potential not only to suggest new research directions, but also to lead to the identification of novel therapeutic agents. Although several novel migraine medications are becoming available, their effectiveness, tolerability, and safety often remain uncertain in older adults, who have commonly been excluded from the evaluation of these agents in randomised controlled trials, or who constitute only a small proportion of study populations. There is a need to recognise these limitations in the available evidence, and the specific, and often unmet, clinical needs of older adults with migraine, not least because older adults constitute an increasing proportion of populations worldwide.

Calcitonin Gene-Related peptide receptor antagonist suppresses allergic asthma responses via downregulation of group 2 innate lymphoid cells in mice

Allergic asthma is caused by chronic inflammation and hyper-responsiveness of the airway and is thought to be mediated by adaptive T helper type 2 (Th2)-driven immunity. However, recent studies have demonstrated that neuropeptide calcitonin gene-related peptide (CGRP)-mediated activation of group 2 innate lymphoid cells (ILC2s) may contribute to the development of asthma pathogenesis. Here, we investigated the therapeutic effects of the systemic administration of rimegepant, a CGRP receptor antagonist, on allergic asthma. Hyperplasia of CGRP-immunoreactive pulmonary neuroendocrine cells (PNECs) was observed in ovalbumin (OVA)-induced asthmatic mice. Concomitant with this, we observed an increase in the content of total lung CGRP. Upon antigen challenge, the concentration of plasma CGRP was transiently upregulated, whereas CGRP immunoreactivity within PNECs was intensively downregulated, suggesting that PNECs were the most likely source of CGRP. When rimegepant was administered according to CGRP kinetics, it suppressed asthma phenotypes, including airway hyper-responsiveness, infiltration of inflammatory cells in bronchoalveolar lavage fluid (BALF), hyperplasia of mucus-producing cells, and production of the Th2 cytokine IL-5. Moreover, we observed a decrease in the number of ILC2s and their capacity for IL-5 release in the presence of IL-33 in rimegepant-treated mice. In the allergic asthma model, rimegepant suppressed the activation of ILC2s mediated by PNEC-derived CGRP and subsequently impaired adaptive Th2-driven immunity, which ameliorated asthmatic phenotypes. Thus, an anti-CGRP signal strategy to target ILC2 will be a novel and attractive approach for treating allergic asthma that is refractory to other treatments.

Ten open questions in migraine prophylaxis with monoclonal antibodies blocking the calcitonin-gene related peptide pathway: a narrative review

The monoclonal antibodies (mAbs) blocking the calcitonin-gene related peptide (CGRP) pathway, collectively called here "anti-CGRP/rec mAbs", have dramatically improved preventive migraine treatment. Although their efficacy and tolerability were proven in a number of randomized controlled trials (RCTs) and, maybe even more convincingly, in real world settings, a number of open questions remain. In this narrative review, we will analyze published data allowing insight in some of the uncertainties related to the use of anti-CGRP/rec mAbs in clinical practice: their differential efficacy in migraine subtypes, outcome predictors, switching between molecules, use in children and adolescents, long-term treatment adherence and persistence, effect persistence after discontinuation, combined treatment with botulinum toxin or gepants, added-value and cost effectiveness, effectiveness in other headache types, and potential contraindications based on known physiological effects of CGRP. While recent studies have already provided hints for some of these questions, many of them will not find reliable and definitive answers before larger studies, registries or dedicated RCTs are available.

Blocking the CGRP Receptor: Differences across Human Vascular Beds

Multiple drugs targeting the calcitonin gene-related peptide (CGRP) receptor have been developed for the treatment of migraine. Here, the effect of the small-molecule CGRP receptor antagonist zavegepant (0.1 nM-1 µM) on CGRP-induced relaxation in isolated human coronary arteries (HCAs) was investigated. A Schild plot was constructed and a pA2 value was calculated to determine the potency of zavegepant. The potency and Schild plot slopes of atogepant, olcegepant, rimegepant, telcagepant, ubrogepant and zavegepant in HCAs and human middle meningeal arteries (HMMAs), obtained from our earlier studies, were compared. Zavegepant shifted the concentration-response curve to CGRP in HCAs. The corresponding Schild plot slope was not different from unity, resulting in a pA2 value of 9.92 ± 0.24. No potency difference between HCAs and HMMAs was observed. Interestingly, olcegepant, atogepant and rimegepant, with a Schild plot slope < 1 in HCAs, were all >1 log unit more potent in HMMAs than in HCAs, while telcagepant, ubrogepant and zavegepant, with a Schild plot slope not different from unity, showed similar (<1 log difference) potency across both tissues. As a Schild plot slope < 1 may point to the involvement of multiple receptors, it is important to further identify the receptors involved in the relaxation to CGRP in HCAs, which may be used to improve the cardiovascular safety of future antimigraine drugs.

Calcitonin gene-related peptide: a potential protective agent in cerebral ischemia-reperfusion injury

Ischemic stroke is the most common type of cerebrovascular disease with high disability and mortality rates, which severely burdens patients, their families, and society. At present, thrombolytic therapy is mainly used for the treatment of ischemic strokes. Even though it can achieve a good effect, thrombolytic recanalization can cause reperfusion injury. Calcitonin gene-related peptide (CGRP) is a neuropeptide that plays a neuroprotective role in the process of ischemia-reperfusion injury. By combining with its specific receptors, CGRP can induce vasodilation of local cerebral ischemia by directly activating the cAMP-PKA pathway in vascular smooth muscle cells and by indirectly activating the NO-cGMP pathway in an endothelial cell-dependent manner,thus rapidly increasing ischemic local blood flow together with reperfusion. CGRP, as a key effector molecule of neurogenic inflammation, can reduce the activation of microglia, downregulates Th1 classical inflammation, and reduce the production of TNF-α, IL-2, and IFN-γ and the innate immune response of macrophages, leading to the reduction of inflammatory factors. CGRP can reduce the overexpression of the aquaporin-4 (AQP-4) protein and its mRNA in the cerebral ischemic junction, and play a role in reducing cerebral edema. CGRP can protect endothelial cells from angiotensin II by reducing the production of oxidants and protecting antioxidant defense. Furthermore, CGRP-upregulated eNOS can further induce VEGF expression, which then promotes the survival and angiogenesis of vascular endothelial cells. CGRP can also reduce apoptosis by promoting the expression of Bcl-2 and inhibiting the expression of caspase-3. These effects suggest that CGRP can reduce brain injury and repair damaged nerve function. In this review, we focused on the role of CGRP in cerebral ischemia-reperfusion injury.

The vascular role of CGRP: a systematic review of human studies

Intravenous infusion of human alpha calcitonin gene-related peptide (h-α-CGRP) has been applied to explore migraine pathogenesis and cerebral hemodynamics during the past three decades. Cumulative data implicate h-α-CGRP in regulating the vascular tone. In this systematic review, we searched PubMed and EMBASE for clinical studies investigating the vascular changes upon intravenous infusion of h-α-CGRP in humans. A total of 386 studies were screened by title and abstract. Of these, 11 studies with 61 healthy participants and 177 participants diagnosed with migraine were included. Several studies reported hemodynamic effects including flushing, palpitation, warm sensation, heart rate (HR), mean arterial blood pressure (MABP), mean blood flow velocity of middle cerebral artery (mean V_MCA), and diameter of superficial temporal artery (STA). Upon the start of h-α-CGRP infusion, 163 of 165 (99%) participants had flushing, 98 of 155 (63%) participants reported palpitation, and 160 of 165 (97%) participants reported warm sensation. HR increased with 14%-58% and MABP decreased with 7%-12%. The mean V_MCA was decreased with 9.5%-21%, and the diameter of the STA was dilated with 41%-43%. The vascular changes lasted from 20 to >120 min. Intravenous infusion of h-α-CGRP caused a universal vasodilation without any serious adverse events. The involvement of CGRP in the systemic hemodynamic raises concerns regarding long-term blockade of CGRP in migraine patients with and without cardiovascular complications.

Neurological and psychiatric comorbidities of migraine: Concepts and future perspectives

BACKGROUND

This narrative review aims to discuss several common neurological and psychiatric disorders that show comorbidity with migraine. Not only can we gain pathophysiological insights by studying these disorders, comorbidities also have important implications for treating migraine patients in clinical practice.

METHODS

A literature search on PubMed and Embase was conducted with the keywords "comorbidity", "migraine disorders", "migraine with aura", "migraine without aura", "depression", "depressive disorders", "epilepsy", "stroke", "patent foramen ovale", "sleep wake disorders", "restless legs syndrome", "genetics", "therapeutics".

RESULTS

Several common neurological and psychiatric disorders show comorbidity with migraine. Major depression and migraine show bidirectional causality and have shared genetic factors. Dysregulation of both hypothalamic and thalamic pathways have been implicated as a possibly cause. The increased risk of ischaemic stroke in migraine likely involves spreading depolarizations. Epilepsy is not only bidirectionally related to migraine, but is also co-occurring in monogenic migraine syndromes. Neuronal hyperexcitability is an important overlapping mechanism between these conditions. Hypothalamic dysfunction is suggested as the underlying mechanism for comorbidity between sleep disorders and migraine and might explain altered circadian timing in migraine.

CONCLUSION

These comorbid conditions in migraine with distinct pathophysiological mechanisms have important implications for best treatment choices and may provide clues for future approaches.

[Cardiovascular safety of new drugs for the acute and preventive treatment of migraine: gepants and ditans]

INTRODUCTION

Migraine is a prevalent neurological condition characterised by disabling headache attacks. In recent decades, new drugs have been developed specifically for the acute and preventive treatment of migraine based on its pathophysiology. These include calcitonin gene-related peptide (CGRP) antagonists (CGRP) (gepants) and selective serotoninergic 5-HT1F receptor agonists (ditans). CGRP is a neuropeptide released by trigeminal terminals that acts as a vasodilator, causes neurogenic inflammation and thus generates pain and sensitisation in migraine. It also has a powerful vasodilatory action and is involved in cardiovascular regulation, which is why numerous studies are under way to assess the vascular safety of acting against CGRP. The high selectivity of ditans for the serotoninergic 5-HT1F receptor with a low affinity for other serotoninergic receptors seems to translate into little or no vasoconstrictor effect, which is mediated by the activation of 5-HT1B receptors.

DEVELOPMENT

The aim of our study is to review the cardiovascular safety demonstrated by these new drugs for the treatment of migraine by analysing the evidence published to date. We conducted a literature search in the PubMed database and a review of clinical trials published at clinicaltrial.gov. We included literature reviews, meta-analyses and clinical trials in English and Spanish. We analysed reported cardiovascular adverse effects.

CONCLUSIONS

Based on the results published to date, we can conclude that the cardiovascular safety profile of these new treatments is favourable. Longer-term safety studies are needed to confirm these results.

Optogenetic Spreading Depolarizations Do Not Worsen Acute Ischemic Stroke Outcome

BACKGROUND

Spreading depolarizations (SDs) are believed to contribute to injury progression and worsen outcomes in focal cerebral ischemia because exogenously induced SDs have been associated with enlarged infarct volumes. However, previous studies used highly invasive methods to trigger SDs that can directly cause tissue injury (eg, topical KCl) and confound the interpretation. Here, we tested whether SDs indeed enlarge infarcts when induced via a novel, noninjurious method using optogenetics.

METHODS

Using transgenic mice expressing channelrhodopsin-2 in neurons (Thy1-ChR2-YFP), we induced 8 optogenetic SDs to trigger SDs noninvasively at a remote cortical location in a noninjurious manner during 1-hour distal microvascular clip or proximal an endovascular filament occlusion of the middle cerebral artery. Laser speckle imaging was used to monitor cerebral blood flow. Infarct volumes were then quantified at 24 or 48 hours.

RESULTS

Infarct volumes in the optogenetic SD arm did not differ from the control arm in either distal or proximal middle cerebral artery occlusion, despite a 6-fold and 4-fold higher number of SDs, respectively. Identical optogenetic illumination in wild-type mice did not affect the infarct volume. Full-field laser speckle imaging showed that optogenetic stimulation did not affect the perfusion in the peri-infarct cortex.

CONCLUSIONS

Altogether, these data show that SDs induced noninvasively using optogenetics do not worsen tissue outcomes. Our findings compel a careful reexamination of the notion that SDs are causally linked to infarct expansion.

Evaluation of vascular risk in patients with migraine with and without aura treated with erenumab: Post hoc analysis of pooled long-term clinical trial data

OBJECTIVE

To assess cardiovascular (CV) safety of erenumab in clinical trial patients associated with degree of CV risk.

BACKGROUND

Hypertension has been considered a theoretical risk associated with the inhibition of the calcitonin gene-related peptide pathway in migraine management, particularly in a patient population with pre-existing CV risk factors.

METHODS

Data pooled from four double-blind, randomized trials were used to assess blood pressure (BP) changes and CV safety in patients grouped based on 10-year risk of cardiac, cerebrovascular, and peripheral artery disease as no-risk-factors, low-risk (>0% to ≤10%), moderate-risk (>10% to ≤20%), and high-risk (>20%) categories. CV safety was assessed as ischemic cardiovascular and cerebrovascular adverse events (ICCAE).

RESULTS

There was no apparent difference between placebo- (N = 1032) and erenumab-treatment groups (70 mg, N = 885; 140 mg, N = 504) in clinical worsening of BP category from baseline to Months 1-3 (14% [143/1032] placebo vs. 13% [114/885] and 14% [71/504] for erenumab 70 and 140 mg, respectively) regardless of baseline BP category. The adverse event (AE) profile of erenumab was similar across CV risk categories throughout the long-term analysis. Erenumab-treated patients with high and moderate 10-year CV risk (N = 107) did not experience any ICCAEs during the double-blind treatment period; there was a single ICCAE (a cerebral dural venous sinus thrombosis) observed in the low-risk erenumab group (N = 273). There were no increases in AEs during the long-term extensions of up to 5 years (N = 2499; 3482 patient-years of exposure to erenumab) with exposure-adjusted incidence rates of cardio/cerebrovascular disorder AEs of 0.4, 0.5, 0.0, and 1.1 (per 100 patient-years) for no risk factor (N = 1805), low (N = 492), moderate (N = 121), and high (N = 81) 10-year CV risk groups, respectively.

CONCLUSIONS

Ischemic CV and cerebrovascular AEs were uncommon and the incidence rates were similar across the 10-year CV risk categories. This analysis helps provide more detail on the CV safety of erenumab.

Calcitonin gene-related peptide (CGRP) monoclonal antibodies for migraine

The introduction of calcitonin gene-related peptide monoclonal antibodies represents a step forward in preventive migraine treatment as the first agents to target the underlying pathogenesis of migraine. In trials they act more quickly, have better long-term adherence and appear to be better tolerated than other treatments. Major disadvantages are their high cost and unknown safety in pregnancy and in cardiovascular disease. To mitigate these concerns, they should be used according to guidance produced by professional bodies, with defined starting and stopping criteria. We do not yet know whether they are more effective than standard care; many patients may still be better treated by other means, in particular addressing lifestyle factors and medication-overuse headache.

Real-World Patient Experience of CGRP-Targeting Therapy for Migraine: a Narrative Review

PURPOSE OF REVIEW

To summarize available calcitonin gene-related peptide (CGRP)-targeting therapies for migraine and discuss their use in real-world populations.

BACKGROUND

CGRP has long been a topic of interest in migraine pathophysiology, with new therapies targeting CGRP since 2018 for both the preventive and acute treatment of migraine.

METHODS

We searched PubMed using keywords including "migraine," "CGRP," "real-world," "erenumab," "galcanezumab," "fremanezumab," "eptinezumab," "ubrogepant," "rimegepant," and "atogepant." We reviewed all pertinent studies and summarized main findings. We also compiled detailed patient characteristics (e.g., migraine diagnoses, medication overuse, prior treatment failures) and treatment outcome measures, such as 50% responder rates, reduction in migraine days, and adverse event rates in several tables. Overall, studies reporting real-world patient experiences of CGRP-targeting therapies suggested meaningful effectiveness for migraine treatment with response rates comparable to the numbers reported in clinical trials. Furthermore, studies suggested benefit in patients with multiple prior unsuccessful treatment trials, medication overuse, and complex medical comorbidities. In some studies, adverse event rates have been notably higher than reported in clinical trials. Additional long-term data is needed to further evaluate sustained efficacy, predictors of treatment response, and adverse events.

Gepants - a long way to cure: a narrative review

Calcitonin gene-related peptide (CGRP) is probably the most potent vasodilator in cerebral circulation. Forty years after its discovery, the new CGRP-targeted therapy monoclonal antibodies, and the small molecule gepants, are now available for clinical practice. While randomized controlled trials and real-world experience consistently demonstrated the high efficacy and tolerability of monoclonal antibodies, limited evidence is available to characterize gepants fully. Depending on pharmacokinetics, these CGRP receptor antagonists can be used for acute (ubrogepant, rimegepant, and the not yet approved zavegepant) or preventive (atogepant and rimegepant) migraine treatment. Randomized placebo-controlled trials demonstrated gepants efficacy in treating acute attacks to obtain 2 h pain freedom in about 20% of patients and pain relief in about 60%, while up to 60% of treated patients with episodic migraine may experience a 50% reduction in monthly migraine days. The most common treatment-related emergent adverse events were gastrointestinal (nausea, constipation) for the acute or preventive use. No vascular or hepatic concerns have emerged so far. More studies are ongoing to investigate gepant tolerability and safety also if associated with monoclonal antibodies targeting CGRP and other therapeutic classes. Gepants are also under investigation to treat other painful and non-painful conditions. Real-life studies are necessary to confirm the trials’ findings and investigate more practical clinical aspects.

Acute Treatment of Headache (Focus on Migraine)

Acute treatments for migraine and cluster headache are necessary to abort attacks, relieve pain and associated symptoms, and restore an individual's ability to function. Acute headache treatments consist of a variety of medication and nonmedication options. In this article, we discuss the approach to acute treatment of migraine and cluster headache. We summarize the level of evidence to support each acute medication class according to recent systematic reviews and meta-analyses, as well as guideline recommendations from the American Headache Society, American Academy of Neurology, and European Federation of Neurological Society.

Galcanezumab modulates Capsaicin-induced C-fiber reactivity

Background

The vasodilatory calcitonin-gene related peptide (CGRP) is understood as pivotal mediator in migraine pathophysiology. Blocking CGRP with small molecules or monoclonal antibodies (CGRP-mAb) reduces migraine frequency. However, prescription of CGRP-mAbs is still regulated and possible predictive measures of therapeutic success would be useful.

Methods

Using standardized capsaicin-induced dermal blood flow model, 29 migraine patients underwent a laser speckle imaging measurement before and after administration of galcanezumab. At both sessions dermal blood flow before and after capsaicin stimulation as well as flare size were analyzed over all three trigeminal branches and the volar forearm for extracranial control. Long-term measures were repeated in 14 patients after continuous treatment ranging from 6 to 12 months.

Results

Resting dermal blood flow remained unchanged after administration of galcanezumab. Capsaicin-induced dermal blood flow decreased significantly after CGRP-mAb in all tested areas compared to baseline and this was consistent even after 12 months of treatment. However, following galcanezumab administration, the flare size decreased only in the three trigeminal dermatomes, not the arm and was therefore specific for the trigemino-vascular system. None of these two markers distinguished between responders and non-responders.

Conclusion

CGRP-mAb changed blood flow response to capsaicin stimulation profoundly and this effect did not change over a 12-month application. Neither capsaicin-induced flare nor dermal blood flow can be used as a predictor for treatment efficacy. These data suggest that the mechanism of headache development in migraine is not entirely CGRP-mediated.

Cardiovascular Disease and Migraine: Are the New Treatments Safe?

PURPOSE OF REVIEW

The authors present data on cardiovascular safety for the new acute and preventive migraine treatments including ditans, gepants, and calcitonin gene-related peptide monoclonal antibodies (CGRP mAbs) alongside older medications like triptans and ergotamines.

RECENT FINDINGS

The authors conclude that there are no cardiovascular safety concerns for lasmiditan, and that it could be used in those with cardiovascular disease. In fact, the literature even suggests that triptans are safer in cardiovascular disease than their contraindications may suggest. At this time, there is insufficient evidence that gepants and CGRP mAbs should be contraindicated in those with cardiovascular disease including stroke or myocardial infarction, though erenumab has now been associated with hypertension. Vasodilation may be an important CGRP-mediated mechanism mid-ischemia especially in patients with small vessel disease; hence, CGRP antagonists should be use with caution in this context. Long-term data is still needed, and prescribers should ensure patients are aware of the limitations of our knowledge at this time, while still offering these effective and well-tolerated treatment options.

A history of International Headache Society grants and their impact on headache careers

Background

The International Headache Society has been offering multiple award opportunities for young researchers and clinicians for many years, with the aim of supporting the development of careers in headache science and medicine.

Methods

In order to assess the outcomes of the International Headache Society award grants, a questionnaire was sent to all previous recipients, investigating a series of aspects related to their work, both during and after award completion.

Results

Of 44 total questionnaires sent, 36 were returned. Eighty-one percent of the recipients reported to have remained in the headache field since the award, half of them held a current academic position and over three-quarters had stayed in contact with the host institution. The totality of questionnaire responders stated that the grant had had a significantly positive impact on their careers.

Conclusions

The International Headache Society grants have assisted many young researchers in building an academic and clinical career in the field of headache, throughout the years.

European Headache Federation guideline on the use of monoclonal antibodies targeting the calcitonin gene related peptide pathway for migraine prevention - 2022 update

Background

A previous European Headache Federation (EHF) guideline addressed the use of monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway to prevent migraine. Since then, randomized controlled trials (RCTs) and real-world evidence have expanded the evidence and knowledge for those treatments. Therefore, the EHF panel decided to provide an updated guideline on the use of those treatments.

Methods

The guideline was developed following the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. The working group identified relevant questions, performed a systematic review and an analysis of the literature, assessed the quality of the available evidence, and wrote recommendations. Where the GRADE approach was not applicable, expert opinion was provided.

Results

We found moderate to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in individuals with episodic and chronic migraine. For several important clinical questions, we found not enough evidence to provide evidence-based recommendations and guidance relied on experts’ opinion. Nevertheless, we provided updated suggestions regarding the long-term management of those treatments and their place with respect to the other migraine preventatives.

Conclusion

Monoclonal antibodies targeting the CGRP pathway are recommended for migraine prevention as they are effective and safe also in the long-term.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01431-x.

Therapies targeting CGRP signaling for medication overuse headache

PURPOSE OF REVIEW

Medication overuse headache (MOH) affects more than 60 million individuals worldwide causing enormous personal and social burden. Only repurposed drugs are available for MOH that share limited evidence for efficacy. The preclinical data suggesting that activation of the calcitonin gene-related peptide (CGRP) pathway is involved in headache chronification along with clinical evidence that monoclonal antibodies targeting CGRP (anti-CGRP mAbs) have good efficacy in preventing chronic migraine, triggered this review that aims to summarize the current data on the effectiveness and safety of mAbs against CGRP in MOH.

RECENT FINDINGS

Post hoc analyses of phase-3 trials of erenumab, fremanezumab, galcanezumab, and eptinezumab for the prevention of chronic migraine revealed that patients with MOH benefit from the treatment over placebo. Several real-world studies confirm the efficacy of erenumab and galcanezumab in patients with MO. However, all published trials evaluated treatments in patients with chronic migraine with MO collectively, not in patients with MOH exclusively.

SUMMARY

The available data indicate that anti-CGRP mAbs represent a good mechanism-based and disease-specific therapeutical option with for MOH as long as detoxification and additional nonpharmaceutical interventions are operated. Future research should focus on long-term-controlled trials in MOH populations exclusively.

Drug Safety in Episodic Migraine Management in Adults. Part 2: Preventive Treatments

PURPOSE OF REVIEW

The aim of this review is to aid in decision-making when choosing safe and effective options for preventive migraine medications.

RECENT FINDINGS

In Part 2, we have compiled clinically relevant safety considerations for commonly used migraine prophylactic treatments. Preventive treatment of episodic migraine includes nonspecific and migraine-specific drugs. While medications from several pharmacological classes-such as anticonvulsants, beta-blockers, and antidepressants-have an established efficacy in migraine prevention, they are associated with a number of side effects. The safety of migraine-specific treatments such as anti-CGRP monoclonal antibodies and gepants are also discussed. This review highlights safety concerns of commonly used migraine prophylactic agents and offers suggestions on how to mitigate those risks.

Drug Safety in Episodic Migraine Management in Adults Part 1: Acute Treatments

PURPOSE OF REVIEW

The aim of this review is to aid in choosing safe options when assessing potential risks of acute migraine treatments based on known mechanisms of action and anticipated safety concerns.

RECENT FINDINGS

Part 1 highlights safety issues associated with commonly used medications to treat acute migraine attacks. Strategies to mitigate cardiovascular and gastrointestinal risks of nonsteroidal anti-inflammatory drugs, evaluation of cardiovascular risks of triptan and ergot alkaloids, and precautions with use of antiemetics and the novel drugs gepants and ditans are discussed to help practitioners in clinical decision-making. When available, we included recommendations from professional societies and data from pharmacovigilance systems. While guidelines on efficacy are available, one must also consider the possible risks and adverse effects of a drug when creating treatment plans.

Migraine Prevention with Erenumab: Focus on Patient Selection, Perspectives and Outcomes

Erenumab is a monoclonal antibody targeting the calcitonin gene-related peptide (CGRP) receptor suitable for episodic and chronic migraine prevention. Randomized clinical trials proved the superiority of erenumab to placebo in a strictly selected population, while real-world studies confirmed treatment efficacy in more severe forms of disease – most patients suffered from chronic migraine with medication overuse headache, had prior treatment failures, and long disease duration. According to guidelines, anti-CGRP pathway monoclonal antibodies should be reserved to patients who failed or have contraindication to several classes of preventive treatments. However, their ease of use, tolerability and efficacy make these monoclonal antibodies ideally suitable for most patients with migraine; cost-effectiveness needs to be considered when looking at expanding current prescription criteria. Also, data from open label extensions of randomized control trials confirmed sustained benefits of prolonged treatment up to 5 consecutive years without significant risk of adverse events. Further studies will provide insights on optimal treatment duration to achieve migraine remission and predictors of treatment response. In the present work, we aimed at reviewing design and results of the main studies on erenumab and discussing treatment use in the current migraine prevention scenario; we also summarized the main ongoing research projects and provided clinical perspectives for the future.

Anti-nociceptive effects of dual neuropeptide antagonist therapy in mouse model of neuropathic and inflammatory pain

Background

Neurokinin-1 (NK1) and calcitonin gene-related peptide (CGRP) play a vital role in pain pathogenesis, and these proteins' antagonists have attracted attention as promising pharmaceutical candidates. The authors investigated the antinociceptive effect of co-administration of the CGRP antagonist and an NK1 antagonist on pain models compared to conventional single regimens.

Methods

C57Bl/6J mice underwent sciatic nerve ligation for the neuropathic pain model and were injected with 4% formalin into the hind paw for the inflammatory pain model. Each model was divided into four groups: vehicle, NK1 antagonist, CGRP antagonist, and combination treatment groups. The NK1 antagonist aprepitant (BIBN4096, 1 mg/kg) or the CGRP antagonist olcegepant (MK-0869, 10 mg/kg) was injected intraperitoneally. Mechanical allodynia, thermal hypersensitivity, and anxiety-related behaviors were assessed using the von Frey, hot plate, and elevated plus-maze tests. The flinching and licking responses were also evaluated after formalin injection.

Results

Co-administration of aprepitant and olcegepant more significantly alleviated pain behaviors than administration of single agents or vehicle, increasing the mechanical threshold and improving the response latency. Anxiety-related behaviors were also markedly improved after dual treatment compared with either naive mice or the neuropathic pain model in the dual treatment group. Flinching frequency and licking response after formalin injection decreased significantly in the dual treatment group. Isobolographic analysis showed a meaningful additive effect between the two compounds.

Conclusions

A combination pharmacological therapy comprised of multiple neuropeptide antagonists could be a more effective therapeutic strategy for alleviating neuropathic or inflammatory pain.

Role of Atogepant in the Treatment of Episodic Migraines: Clinical Perspectives and Considerations

Advances in molecular biology and neuroscience have led to the discovery of calcitonin gene-related peptide (CGRP), a 37 amino-acid neuropeptide that plays a critical role in the pathogenesis of migraine. CGRP receptor antagonist, also known as gepant, is an oral medication that inhibits the CGRP-related nociceptive signaling pathway. To date, three gepants are approved by the FDA for migraine treatment. Atogepant is a 2nd-generation gepant that non-competitively antagonizes CGRP receptors inhibiting neurogenic inflammation and pain sensitization. With its long half-life and minimal cardiovascular or liver toxicity, it is the first in its class approved primarily for migraine prevention. This article will discuss the evidence, safety, and rationale of atogepant for use in clinical practice.

The Neuropeptide α-Calcitonin Gene-Related Peptide as the Mediator of Beneficial Effects of Exercise in the Cardiovascular System

Regular physical activity exerts cardiovascular protective effects in healthy individuals and those with chronic cardiovascular diseases. Exercise is accompanied by an increased plasma concentration of α-calcitonin gene-related peptide (αCGRP), a 37-amino acid peptide with vasodilatory effects and causative roles in migraine. Moreover, mouse models revealed that loss of αCGRP disrupts physiological adaptation of the cardiovascular system to exercise in normotension and aggravates cardiovascular impairment in primary chronic hypertension, both can be reversed by αCGRP administration. This suggests that αCGRP agonists could be a therapeutic option to mediate the cardiovascular protective effects of exercise in clinical setting where exercise is not possible or contraindicated. Of note, FDA has recently approved αCGRP antagonists for migraine prophylaxis therapy, however, the cardiovascular safety of long-term anti-CGRP therapy in individuals with cardiovascular diseases has yet to be established. Current evidence from preclinical models suggests that chronic αCGRP antagonism may abolish the cardiovascular protective effects of exercise in both normotension and chronic hypertension.

Atogepant: an emerging treatment for migraine

INTRODUCTION

Until recently, only nonspecific and not always well-tolerated medications were available for migraine prophylaxis. Currently, specific drugs such as calcitonin gene-related peptide (CGRP) monoclonal antibodies and second-generation gepants are marketed for migraine treatment. Atogepant, an orally active small molecule, is a potent, selective antagonist of the CGRP receptor and is the only gepant authorized exclusively for episodic migraine prophylaxis in adults.

AREAS COVERED

Using literature obtained from PubMed, Scopus, Web of Science, Cochrane, and ClinicalTrials.gov (up to February 13^rd, 2022), the authors summarize and evaluate the available data on atogepant for the prophylaxis of episodic migraine.

EXPERT OPINION

From pivotal trials, the efficacy and tolerability of atogepant in episodic migraine prophylaxis seem comparable to those of CGRP monoclonal antibodies, even if comparative studies have not been conducted. To date, limited information is available on atogepant, including the optimal dose and duration of therapy; hence, it is difficult to establish whether it could be a first-line drug for migraine prophylaxis. Furthermore, it is important to evaluate if atogepant use is associated with the risk of cardiovascular and cerebrovascular events, which could result from potent and persistent blockade of vasodilation by CGRP.

Safety and tolerability of fremanezumab in patients with episodic and chronic migraine: a pooled analysis of phase 3 studies

Background

Fremanezumab, a fully humanized monoclonal antibody that selectively targets calcitonin gene-related peptide, has demonstrated efficacy for preventive treatment of episodic and chronic migraine. Since calcitonin gene-related peptide is expressed within the cardio- and cerebrovascular system and may have cardioprotective effects, it is critical to understand the cardio- and cerebrovascular safety of fremanezumab.

Methods

This was a pooled analysis of three randomized, double-blind, placebo-controlled, phase 3, 12-week trials in which patients with episodic migraine or chronic migraine received quarterly fremanezumab, monthly fremanezumab, or placebo. Incidences of overall and serious adverse events were analyzed. Cardio- and cerebrovascular adverse events (CVAEs) were analyzed in subgroups stratified by cardio- and cerebrovascular medical history, cardiovascular risk factors (CVRFs), and use of cardio- and cerebrovascular medications or triptans.

Results

Two thousand, eight hundred and forty-two patients were included in the study. Overall (58–65%) and serious adverse events (<1–2%) occurred in similar proportions across fremanezumab and placebo groups. CVAEs were infrequent, regardless of cardio- and cerebrovascular medical history (2–6%). CVAEs occurred in low, similar proportions of patients with CVRFs and those using cardio- and cerebrovascular medications or triptans. No cardio- and cerebrovascular signals were identified.

Conclusion

Fremanezumab demonstrated a favorable overall and cardio- and cerebrovascular safety profile in more than 2800 patients with episodic migraine or chronic migraine, regardless of cardio- and cerebrovascular medical history, CVRFs, or medication use.

Trial Registrations: NCT02629861 (HALO EM, https://clinicaltrials.gov/ct2/show/NCT02629861), NCT02621931 (HALO CM, https://clinicaltrials.gov/ct2/show/NCT02621931), NCT03308968 (FOCUS, https://clinicaltrials.gov/ct2/ show/NCT03308968)

Higher Circulating Vitamin D Levels Are Associated With Decreased Migraine Risk: A Mendelian Randomization Study

Background

Evidence showed the supplementation of vitamin D might have beneficial effects for migraine patients. We aimed to investigate the causal effects of serum vitamin D levels on migraine risk using two-sample Mendelian randomization (MR) method.

Methods

A total of 184 independent genetic instruments for serum vitamin D levels were selected from a study in 417,580 Europeans from UK biobank. Six variants from an independent study were obtained to perform replication analysis. Summary-level data for migraine were obtained from three studies with 48,975 migraine cases, 28,852 migraine cases and 10,536 migraine cases, respectively.

Results

The estimated odds ratios (ORs) per standard deviation increase in circulating vitamin D levels based on the three migraine datasets were 0.948 (95% CI = 0.883-1.016, p = 0.133), 0.902 (95% confidence intervals [CI] = 0.825-0.986, p = 0.023), and 0.880 (95% CI = 0.786-0.984, p = 0.025), respectively. Using pooled migraine summary data with no sample overlap, MR analysis showed per standard deviation increase in circulating vitamin D levels was significantly associated with a decreased migraine risk (OR = 0.916, 95% CI = 0.859-0.977, p = 0.008). Multivariable MR analyses, sensitivity analyses and replication analysis confirmed the association. MR analyses showed similar estimates for migraine with aura and migraine without aura but with wider 95% CIs. Mediation analysis showed the effect of vitamin D on migraine risk via pathway of serum calcium was corresponding to an OR of 1.003 (95% CI = 1.001-1.005) and a proportion mediated of 3.42%. The reverse MR analysis showed migraine might not affect vitamin D levels.

Conclusion

This two-sample MR study showed genetically determined increased circulating vitamin D levels are associated with decreased migraine risk. The effect seems consistent across different migraine subtypes. In addition, the role of serum calcium in mediating the association between vitamin D and migraine is negligible. Future large well-designed randomized trials are warranted to assess the effects of vitamin D supplementation for migraine patients, especially in those with vitamin D deficiency.

Cardiovascular outcomes in adults with migraine treated with eptinezumab for migraine prevention: pooled data from four randomized, double-blind, placebo-controlled studies

Background

Patients with migraine have an increased relative risk of cardio- and cerebrovascular events, and some migraine treatments may exacerbate this risk. The primary objective of this analysis was to determine whether the rate of cardiovascular adverse events was higher for patients with migraine treated with the migraine-preventive eptinezumab, compared with patients receiving placebo.

Methods

Cardiovascular outcomes in patients with migraine were pooled across four clinical trials (phase 1b, phase 2, and two phase 3 trials) for use of eptinezumab as a preventive migraine treatment for up to 1 year. In all studies, treatment-emergent adverse events (TEAEs) that occurred after the first dose of study treatment (eptinezumab 100 mg, 300 mg, 1000 mg, or placebo) and vital signs were recorded through study completion.

Results

Cardiovascular TEAEs were rare across all four clinical trials, and rates were similar between patients receiving eptinezumab and those receiving placebo. Cardiovascular TEAEs that did occur were mild or moderate in severity; there were no serious adverse events as per FDA definition. Vital signs (systolic blood pressure, diastolic blood pressure, and heart rate) were not meaningfully different across treatment groups over the course of 56 weeks, compared to placebo. Treatment with eptinezumab did not result in significant new or changed cardiovascular medications used concomitantly compared to placebo.

Conclusions

In this post hoc analysis of four clinical trials for eptinezumab, doses of 100 mg, 300 mg, and 1000 mg (more than 3 times the highest approved dose) were not associated with clinically relevant changes in vital signs or significant changes in concomitant cardiovascular medication usage, and had low incidences of cardiovascular TEAEs, comparable to placebo.

Trial registration

NCT01772524 (Study 2), 01/21/2013; NCT02275117 (Study 5), 10/27/2014; NCT02559895 (PROMISE-1), 09/25/2017; NCT02974153 (PROMISE-2), 11/28/2016

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01360-1.

Evaluation and treatment of headache associated with moyamoya disease - a narrative review

BACKGROUND

Headache in patients with moyamoya disease is an under-addressed topic in the medical literature. Delay in the diagnosis of moyamoya disease or inappropriate treatment of headache could lead to devastating cerebrovascular outcome. With the evolving understanding of moyamoya disease, migraine pathophysiology, and various migraine-specific medications that have become available, it is crucial to provide an updated overview on this topic.

METHODS

We searched PubMed for keywords including moyamoya disease, moyamoya syndrome, headache in moyamoya, surgical revascularization, surgical bypass, migraine and moyamoya, and calcitonin gene-related peptide (CGRP). We summarized the literature and provide a comprehensive review of the headache presentation, possible mechanisms, the impact of various surgical revascularizations on headache in patients with moyamoya disease, and the medical management of headache incorporating novel migraine-specific treatments.Results and conclusion: The most common headache phenotype is migraine; tension-type headache, hemiplegic migraine, and cluster headache have also been reported. Most patients experience improvement of headache after surgical revascularization, though some patients report worsening, or new-onset headache after surgery. Given the complexity of moyamoya disease, careful consideration of different types of medical therapy for headache is necessary to improve the quality of life while not increasing the risk of adverse cerebrovascular events. More prospective studies are warranted to better understand and manage headache in patients with moyamoya disease.

Roles of calcitonin gene-related peptide in the skin, and other physiological and pathophysiological functions

Skin immunity is regulated by many mediator molecules. One is the neuropeptide calcitonin gene-related peptide (CGRP). CGRP has roles in regulating the function of components of the immune system including T cells, B cells, dendritic cells (DCs), endothelial cells (ECs), and mast cells (MCs).

Herein we discuss actions of CGRP in mediating inflammatory and vascular effects in various cutaneous models and disorders.

•

CGRP can help to recruit immune cells through endothelium-dependent vasodilation.

•

CGRP plays an important role in the pathogenesis of neurogenic inflammation.

•

Functions of many components in the immune system are influenced by CGRP.

•

CGRP regulates various inflammatory processes in human skin by affecting different cell-types.

A critical review of the neurovascular nature of migraine and the main mechanisms of action of prophylactic antimigraine medications

INTRODUCTION

Migraine involves neurovascular, functional, and anatomical alterations. Migraineurs experience an intense unilateral and pulsatile headache frequently accompanied with vomiting, nausea, photophobia, etc. Although there is no ideal preventive medication, frequency in migraine days may be partially decreased by some prophylactics, including antihypertensives, antidepressants, antiepileptics, and CGRPergic inhibitors. However, the mechanisms of action involved in antimigraine prophylaxis remain elusive.

AREAS COVERED

This review recaps some of the main neurovascular phenomena related to migraine and currently available preventive medications. Moreover, it discusses the major mechanisms of action of the recommended prophylactic medications.

EXPERT OPINION

In the last three years, migraine prophylaxis has evolved from nonspecific to specific antimigraine treatments. Overall, nonspecific treatments  mainly involve neural actions, whereas specific pharmacotherapy (represented by CGRP receptor antagonists and CGRPergic monoclonal antibodies) is predominantly mediated by neurovascular mechanisms that may include, among others: (i) reduction in the cortical spreading depression (CSD)-associated events; (ii) inhibition of pain sensitization; (iii) blockade of neurogenic inflammation; and/or (iv) increase in cranial vascular tone. Accordingly, the novel antimigraine prophylaxis promises to be more effective, devoid of significant adverse effects (unlike nonspecific treatments), and more beneficial for the quality of life of migraineurs.

Biological and small molecule strategies in migraine therapy with relation to the calcitonin gene-related peptide family of peptides

Migraine is one of the most common of neurological disorders with a global prevalence of up to 15%. One in five migraineurs have frequent episodic or chronic migraine requiring prophylactic treatment. In recent years, specific pharmacological treatments targeting calcitonin gene-related peptide (CGRP) signalling molecules have provided safe and effective treatments, monoclonal antibodies for prophylaxis and gepants for acute therapy. Albeit beneficial, it is important to understand the molecular mechanisms of these new drugs to better understand migraine pathophysiology and improve therapy. Here, we describe current views on the role of the CGRP family of peptides - CGRP, calcitonin, adrenomedullin, amylin - and their receptors in the trigeminovascular system. All these molecules are present within the trigeminovascular system but differ in expression and localization. It is likely that they have different roles, which can be utilized in providing additional drug targets.

Percutaneous Trigeminal Nerve Stimulation Induces Cerebral Vasodilation in a Dose-Dependent Manner

BACKGROUND

The trigeminal nerve directly innervates key vascular structures both centrally and peripherally. Centrally, it is known to innervate the brainstem and cavernous sinus, whereas peripherally the trigemino-cerebrovascular network innervates the majority of the cerebral vasculature. Upon stimulation, it permits direct modulation of cerebral blood flow (CBF), making the trigeminal nerve a promising target for the management of cerebral vasospasm. However, trigeminally mediated cerebral vasodilation has not been applied to the treatment of vasospasm.

OBJECTIVE

To determine the effect of percutaneous electrical stimulation of the infraorbital branch of the trigeminal nerve (pTNS) on the cerebral vasculature.

METHODS

In order to determine the stimulus-response function of pTNS on cerebral vasodilation, CBF, arterial blood pressure, cerebrovascular resistance, intracranial pressure, cerebral perfusion pressure, cerebrospinal fluid calcitonin gene-related peptide (CGRP) concentrations, and the diameter of cerebral vessels were measured in healthy and subarachnoid hemorrhage (SAH) rats.

RESULTS

The present study demonstrates, for the first time, that pTNS increases brain CGRP concentrations in a dose-dependent manner, thereby producing controllable cerebral vasodilation. This vasodilatory response appears to be independent of the pressor response induced by pTNS, as it is maintained even after transection of the spinal cord at the C5-C6 level and shown to be confined to the infraorbital nerve by administration of lidocaine or destroying it. Furthermore, such pTNS-induced vasodilatory response of cerebral vessels is retained after SAH-induced vasospasm.

CONCLUSION

Our study demonstrates that pTNS is a promising vasodilator and increases CBF, cerebral perfusion, and CGRP concentration both in normal and vasoconstrictive conditions.

CGRP and migraine; from bench to bedside

Migraine treatment has reached a new era with the development of drugs that target the trigeminal neuropeptide calcitonin gene-related peptide (CGRP) or its receptor. The CGRP related therapies offer considerable improvements over existing drugs as they are the first to be designed to act on the trigeminal pain system, more specific and with few adverse events. Small molecule CGRP receptor antagonists, such as rimegepant and ubrogepant, are effective for the acute treatment of migraine headache. In contrast, monoclonal antibodies against CGRP or the CGRP receptor are beneficial for the prophylactic treatments in chronic migraine. Here I will provide a historical overview of the long path that led to their successful development. In addition, I will discuss aspects on the biology of CGRP signalling, the role of CGRP in migraine headache, the efficacy of CGRP targeted treatment, and synthesize what currently is known about the role of CGRP in the trigeminovascular system.

Migraine pharmacology and brain ischemia

Introduction: The aim of this review article was to analyze in details the mechanism of drugs’ effects in the treatment and prevention of a migraine attack, as well as to discuss the hypotheses of migraine pathogenesis.

Migraine attack treatment agents: The main agents for migraine attack treatment have an anti-nociceptive activity.

Agents for migraine preventive treatment: β-blocker propranolol also has anti-serotonin and analgesic activities, and most drugs used for the prophylactic treatment of migraine have a vasodilating activity.

Vascular hypothesis of migraine pathogenesis: Despite numerous studies that have expanded our understanding of migraine pathogenesis, the importance of the vascular component in the pathogenesis of this disease has not questioned yet.

Neurogenic hypotheses of cortical spreading depression: It is necessary to take into account the points of this hypothesis in the context of the pathophysiology of migraine.

Neurochemical serotonin hypotheses of migraine pathogenesis: Serotonin plays an important role in the pathogenesis of migraine.

Trigemino-vascular hypotheses of migraine pathogenesis: The trigemino-vascular hypothesis claims to solve the problem of migraine pain.

Migraine and ischemic brain damage: Migraine is a risk factor for ischemic stroke and cognitive disorders.

Search for the new anti-ischemic anti-migraine preparations: A methodology for the search for new anti-ischemic anti-serotonin drugs for the treatment of migraine is proposed.

Conclusion: Belonging of a drug to one or another pharmacological group does not always correspond to its therapeutic effect on the pathogenetic processes of migraine. Migraine with its variety of forms cannot fit only one of the proposed hypotheses on the pathogenesis of this disease.

Graphical abstract:

Updated review on the link between cortical spreading depression and headache disorders

INTRODUCTION

Experimental animal studies have revealed mechanisms that link cortical spreading depression (CSD) to the trigeminal activation mediating lateralized headache. However, conventional CSD as seen in lissencephalic brain is insufficient to explain some clinical features of aura and migraine headache.

AREAS COVERED

The importance of CSD in headache development including dysfunction of the thalamocortical network, neuroinflammation, calcitonin gene-related peptide, transgenic models, and the role of CSD in migraine triggers, treatment options, neuromodulation and future directions are reviewed.

EXPERT OPINION

The conventional understanding of CSD marching across the hemisphere is invalid in gyrencephalic brains. Thalamocortical dysfunction and interruption of functional cortical network systems by CSD, may provide alternative explanations for clinical manifestations of migraine phases including aura. Not all drugs showing CSD blocking properties in lissencephalic brains, have efficacy in migraine headache and monoclonal antibodies against CGRP ligand/receptors which are effective in migraine treatment, have no impact on aura in humans or CSD properties in rodents. Functional networks and molecular mechanisms mediating and amplifying the effects of limited CSD in migraine brain remain to be investigated to define new targets.