Calcitonin Gene-related Peptide Receptor Antagonist Research Articles

Longitudinal changes in functional connectivity and pain-induced brain activations in patients with migraine: a functional MRI study pre- and post- treatment with Erenumab

BackgroundMigraine involves central and peripheral nervous system mechanisms. Erenumab, an anti-calcitonin gene-related peptide (CGRP) receptor monoclonal antibody with little central nervous system penetrance, is effective for migraine prevention. The objective of this study was to determine if response to erenumab is associated with alterations in brain functional connectivity and pain-induced brain activations.MethodsAdults with 6–25 migraine days per month during a 4-week headache diary run-in phase underwent pre-treatment brain functional MRI (fMRI) that included resting-state functional connectivity and BOLD measurements in response to moderately painful heat stimulation to the forearm. This was followed by two treatments with 140 mg erenumab, at baseline and 4 weeks later. Post-treatment fMRI was performed 2 weeks and 8 weeks following the first erenumab treatment. A longitudinal Sandwich estimator analysis was used to identify pre- to post-treatment changes in resting-state functional connectivity and brain activations in response to thermal pain. fMRI findings were compared between erenumab treatment-responders vs. erenumab non-responders.ResultsPre- and post-treatment longitudinal imaging data were available from 32 participants. Average age was 40.3 (+/− 13) years and 29 were female. Pre-treatment average migraine day frequency was 13.8 (+/− 4.7) / 28 days and average headache day frequency was 15.8 (+/− 4.4) / 28 days. Eighteen of 32 (56%) were erenumab responders. Compared to erenumab non-responders, erenumab responders had post-treatment differences in 1) network functional connectivity amongst pain-processing regions, including higher global efficiency, clustering coefficient, node degree, regional efficiency, and modularity, 2) region-to-region functional connectivity between several regions including temporal pole, supramarginal gyrus, and hypothalamus, and 3) pain-induced activations in the middle cingulate, posterior cingulate, and periaqueductal gray matter.ConclusionsReductions in migraine day frequency accompanying erenumab treatment are associated with changes in resting state functional connectivity and central processing of extracranial painful stimuli that differ from erenumab non-responders.Trial registrationclinicaltrials.gov(NCT03773562).

PCR237 Effect of Eptinezumab on Utility Scores in Patients With Migraine: Results From the Deliver Study

Cost-utility modeling informs reimbursement decisions and is based on the premise that health outcome improvements can be expressed as disease-independent utility scores. Previous cost-utility analyses of anti-calcitonin gene-related peptide therapies expressed the utility gain as a function of monthly migraine days (MMDs). Exploring the presence of an additional treatment effect on utility after controlling for MMDs can be insightful. This post hoc analysis of the DELIVER clinical trial (NCT04418765) for the preventive treatment of migraine aims to communicate the impact of eptinezumab on health utility scores.

Commentary: Constipation caused by anti-calcitonin gene-related peptide migraine therapeutics explained by antagonism of calcitonin gene-related peptide's motor-stimulating and prosecretory function in the intestine.

Calcitonin gene-related peptide (CGRP) pathway-targeted treatments have been shown to be efficacious in the prevention of episodic and chronic migraine. Currently approved therapies include monoclonal antibodies (mAbs) that target CGRP (eptinezumab, fremanezumab, and galcanezumab) and the CGRP receptor (erenumab), and small molecule CGRP receptor antagonists (atogepant and rimegepant). While CGRP pathway-targeted treatments are generally well-tolerated, in a review article by Holzer and Holzer-Petsche published in the January 2022 issue of Frontiers in Physiology the authors discussed the role of the CGRP pathway in gastrointestinal physiology, with a specific focus on constipation associated with the use of CGRP pathway-targeted treatments. The authors state that real-world surveys have shown constipation to be a "major adverse event" reported in "more than 50% of patients treated with erenumab, fremanezumab or galcanezumab." As described in the current commentary, the limited data from the cited references in the review article by Holzer and Holzer-Petsche do not support that statement.

Gepants for Acute and Preventive Migraine Treatment: A Narrative Review.

Calcitonin gene-related peptide (CGRP) antagonists are a class of medications that act as antagonists of the CGRP receptor or ligand. They can be divided into monoclonal antibodies and non-peptide small molecules, also known as gepants. CGRP antagonists were the first oral agents specifically designed to prevent migraines. The second generation of gepants includes rimegepant (BHV-3000, BMS-927711), ubrogepant (MK-1602), and atogepant (AGN-241689, MK-8031). Zavegepant (BHV-3500, BMS-742413) belongs to the third generation of gepants characterized by different administration routes. The chemical and pharmacological properties of this new generation of gepants were calculated. The clinical trials showed that the new generation of CGRP antagonists is effective for the acute and/or preventive treatment of migraines. No increased mortality risks were observed to be associated with the second- and third-generation gepants. Moreover, the majority of the serious adverse events reported probably occurred unrelated to the medications. Interesting facts about gepants were highlighted, such as potency, hepatotoxicity, concomitant use with monoclonal antibodies targeting the CGRP, comparative analysis with triptans, and the "acute and preventive" treatment of migraine. Further studies should include an elderly population and compare the medications inside this class and with triptans. There are still concerns regarding the long-term side effects of these medications, such as chronic vascular hemodynamic impairment. Meanwhile, careful pharmacovigilance and safety monitoring should be performed in the clinical practice use of gepants.

Gαs-Coupled CGRP Receptor Signaling Axis from the Trigeminal Ganglion Neuron to Odontoblast Negatively Regulates Dentin Mineralization.

An inflammatory response following dental pulp injury and/or infection often leads to neurogenic inflammation via the axon reflex. However, the detailed mechanism underlying the occurrence of the axon reflex in the dental pulp remains unclear. We sought to examine the intracellular cyclic adenosine monophosphate (cAMP) signaling pathway in odontoblasts via the activation of Gs protein-coupled receptors and intercellular trigeminal ganglion (TG) neuron-odontoblast communication following direct mechanical stimulation of TG neurons. Odontoblasts express heterotrimeric G-protein α-subunit Gαs and calcitonin receptor-like receptors. The application of an adenylyl cyclase (AC) activator and a calcitonin gene-related peptide (CGRP) receptor agonist increased the intracellular cAMP levels ([cAMP]i) in odontoblasts, which were significantly inhibited by the selective CGRP receptor antagonist and AC inhibitor. Mechanical stimulation of the small-sized CGRP-positive but neurofilament heavy chain-negative TG neurons increased [cAMP]i in odontoblasts localized near the stimulated neuron. This increase was inhibited by the CGRP receptor antagonist. In the mineralization assay, CGRP impaired the mineralization ability of the odontoblasts, which was reversed by treatment with a CGRP receptor antagonist and AC inhibitor. CGRP establishes an axon reflex in the dental pulp via intercellular communication between TG neurons and odontoblasts. Overall, CGRP and cAMP signaling negatively regulate dentinogenesis as defensive mechanisms.

Nociceptive Nerves Facilitate Hematopoietic Stem/Progenitor Cell Homing to Bone Marrow By Tuning Microcirculation

The homing process of hematopoietic stem/progenitor cells (HSPCs) to bone marrow (BM) is critical for engraftment after BM transplantation (BMT). Nociceptive nerves in BM reportedly regulate the mobilization of HSPCs from BM by directly supplying calcitonin gene-related peptide (CGRP) to HSPCs. However, it remains unclear whether nociceptive nerves control HSPC dynamics other than egress from BM, e.g., homing to BM. Here, we show that nociceptive nerves facilitate HSPCs homing to BM by controlling microcirculation. To assess the effects of CGRP on the BM microenvironment, we immunostained BM sections of mice and found that BM arteries, but not sinusoids, expressed CGRP receptors. We next employed intravital imaging system that visualized calvarial BM vessels and combined it with the transcalvarial administration (TCA), a method that enables manipulation of local BM microcirculation. TCA of CGRP receptor antagonist constricted BM arteries and decreased sinusoidal flux and shear stress, that impeded transendothelial migration (TEM) of transplanted HSPCs into BM, suggesting that CGRP released from nociceptive nerves supports local BM microcirculation and facilitates TEM of transplanted HSPCs into BM. In addition, systemic administration of CGRP receptor antagonist and pharmacological and genetic ablation of nociceptive nerves significantly decreased the homing efficiency of transplanted HSPCs to BM. Moreover, CGRP administration restored homing efficiency in nociceptive denervated-mice, and improved homing efficiency of wild-type mice. We next examined whether the improved homing efficiency of HSPCs with CGRP administration was mediated via arteries or via hematopoietic cells. CGRP is sensed by a heterodimeric CGRP receptor composed of calcitonin receptor-like receptor (CALCRL) and receptor activity modifying protein 1 (RAMP1), and hematopoietic cells reportedly express both CALCRL and RAMP1. We prepared Ramp1-/- mice to examine the homing efficiency of Ramp1-deficient hematopoietic cells. We found that the homing efficiency of hematopoietic cells from Ramp1-/- mice was not impaired upon transplantation into wild-type recipients. These results suggest that CGRP acts on the BM microenvironments, not on hematopoietic cells, to improve the homing efficiency. To determine the relationship between homing control by nociceptive nerves and survival after transplantation, we analyzed survival after BMT in mice in which nociceptive nerves were denervated. We found that pharmacological and genetic denervation of nociceptive nerves in recipient mice significantly reduced survival after BMT. Finally, to determine whether the intake of spicy food that activates nociceptive nerves enhances the efficiency of BMT, mice were fed with food containing capsaicin and subjected to homing experiments. HSPC homing efficiency to BM of mice fed with capsaicin diet was significantly improved compared to that of mice with normal diet. This study reveals a novel function of nociceptive nerves in regulating BM microcirculation and HSPC homing, and suggests that nociceptive nervous system could be a new therapeutic target for improving BMT efficiency.

Involvement of the calcitonin gene-related peptide system in the modulation of inflamed uterus contractile function in pigs

This study analyzed severe acute endometritis action on myometrial density and distribution of protein gene product (PGP)9.5- and calcitonin gene-related peptide (CGRP)-like immunoreactive nerve fibers and calcitonin receptor-like receptor (CLR) expression, and on CGRP receptor (CGRPR) participation in uterine contractility in pigs. E. coli suspension (E. coli group) or saline (SAL group) were injected into the uteri, or only laparotomy was performed (CON group). In the E. coli group myometrium, a lack of significant changes in PGP9.5 and CGRP innervation patterns and increased CLR protein level were revealed. In all groups, compared to the pretreatment period, human αCGRP increased amplitude in the myometrium, while reducing it in endometrium/myometrium. In the E. coli group endometrium/myometrium, human αCGRP lowered amplitude vs other groups. Human αCGRP reduced frequency in CON and SAL groups and enhanced it in the E. coli group endometrium/myometrium. The frequency in E. coli group increased vs other groups. CGRPR antagonist, human αCGRP8–37, reversed (CON, SAL groups) and eliminated (E. coli group) the rise in human αCGRP-induced myometrial amplitude. In endometrium/myometrium, human αCGRP8–37 abolished (CON group) and reversed (SAL group) a decrease in frequency, and reduced the rise in frequency (E. coli group) caused by human αCGRP. Collectively, in the myometrium, endometritis did not change PGP9.5 and CGRP innervation patterns and enhanced CLR protein level. CGRPR also mediated in CGRP action on inflamed uterus contractility.

Sustained Effects of CGRP Blockade on Cortical Spreading Depolarization-Induced Alterations in Facial Heat Pain Threshold, Light Aversiveness, and Locomotive Activity in the Light Environment.

A migraine is clinically characterized by repeated headache attacks that entail considerable disability. Many patients with migraines experience postdrome, the symptoms of which include tiredness and photophobia. Calcitonin gene-related peptide (GGRP) is critically implicated in migraine pathogenesis. Cortical spreading depolarization (CSD), the biological correlate of migraine aura, sensitizes the trigeminovascular system. In our previous study, CSD caused hypomotility in the light zone and tendency for photophobia at 72 h, at which time trigeminal sensitization had disappeared. We proposed that this CSD-induced disease state would be useful for exploring therapeutic strategies for migraine postdrome. In the present study, we observed that the CGRP receptor antagonist, olcegepant, prevented the hypomotility in the light zone and ameliorated light tolerability at 72 h after CSD induction. Moreover, olcegepant treatment significantly elevated the threshold for facial heat pain at 72 h after CSD. Our results raise the possibility that CGRP blockade may be efficacious in improving hypoactivity in the light environment by enhancing light tolerability during migraine postdrome. Moreover, our data suggest that the CGRP pathway may lower the facial heat pain threshold even in the absence of overt trigeminal sensitization, which provides an important clue to the potential mechanism whereby CGRP blockade confers migraine prophylaxis.

Raynaud's phenomenon associated with calcitonin gene-related peptide receptor antagonists case report.

Calcitonin gene-related peptide (CGRP) is a potent vasodilator that regulates the cerebrovascular and peripheral circulation. A new class of migraine therapies decreases CGRP through various mechanisms. One unknown off-target effect is the impact decreasing CGRP will have on the peripheral circulation. The following cases report new onset Raynaud's phenomenon (RP) following the use of CGRP receptor antagonists (-gepants) for both the acute and preventive treatment of migraine. These cases describe the development of RP in two individuals after using each of the currently available gepant medications. To our knowledge these are the first cases reported of RP associated with the use of gepants. RP has previously been reported in association with monoclonal antibodies to the CGRP ligand and CGRP receptor indicated in the prevention of migraine. One case involved oral CGRP receptor antagonists for acute treatment inducing RP. In this case, rimegepant and ubrogepant used separately for different migraine attacks each led to RP in the digits. The other case involved oral CGRP receptor antagonist, atogepant, used as a preventive treatment and induced RP in the digits. This patient had a prior history of areolar tissue RP while breastfeeding, but never in her fingers. In both cases, the offending medications were discontinued, and the patients reported no further episodes of RP. Two cases are reported of people with migraine with new onset digital RP while taking CGRP receptor antagonists (rimegepant, ubrogepant, atogepant) for acute and preventive treatment.

Calcitonin gene-related peptide (CGRP) receptor antagonists for the acute treatment of migraines in adults.

Migraine headaches are widespread, debilitating and considered a main cause of disability worldwide. Symptoms of migraines include unilateral, pulsating pain that can last for hours to days, frequently associated with photophobia and phonophobia, nausea, or vomiting, and often aggravated by physical activity. The Canadian Headache Society and American Headache Society guidelines suggest strong evidence of the efficacy of triptans, acetaminophen, aspirin, diclofenac sodium, naproxen and ibuprofen for the acute treatment of migraines. The use of calcitonin gene-related peptide (CGRP) antagonists for the treatment and prevention of migraines has been gaining utilization since the approval of the first agent in this class in 2018. There are increasing available options for the acute treatment of migraines. The purpose of this article is to provide a narrative review of the pharmacological and clinical characteristics of ubrogepant and rimegepant and to discuss their implications for use.

Can calcitonin gene-related peptide monoclonal antibody improve migraine and restless legs syndrome?

BackgroundA significant association between migraine and restless legs syndrome (RLS) has been reported, and their coexistence is not uncommon. We report a patient with concomitant migraine and RLS who showed improvement of both migraine and RLS symptoms after treatment with galcanezumab, a calcitonin gene-related peptide (CGRP) monoclonal antibody. Case presentationA 47-year-old woman had been treated in our outpatient headache clinic for migraine without aura. She had RLS since childhood and had been treated with dopamine agonists and α2δ ligands. Over the past 2 months, the patient suffered from frequent migraine headaches and worsening RLS symptoms, despite ongoing treatment. Therefore, galcanezumab was started. After 1 month, the number of headache days decreased from 20 to 4, and her score on the International RLS Study Group Rating Scale improved from 38 to 10. Her photo/phono/osmo-phobia were also markedly improved. The efficacy of galcanezumab for both headache and RLS was sustained over 5 months. ConclusionWe report a case of improvement of both migraine and RLS after treatment with CGRP monoclonal antibody. Additional studies are needed to clarify how CGRP antagonism affects RLS symptoms in patients with migraine and RLS comorbidity.

Novel Macrocyclic Antagonists of the CGRP Receptor Part 2: Stereochemical Inversion Induces an Unprecedented Binding Mode.

The diastereomeric macrocyclic calcitonin gene-related peptide (CGRP) antagonists HTL0029881 (3) and HTL0029882 (4), in which the stereochemistry of a spiro center is reversed, surprisingly demonstrate comparable potency. X-ray crystallographic characterization demonstrates that 3 binds to the CGRP receptor in a precedented manner but that 4 binds in an unprecedented, unexpected, and radically different manner. The observation of this phenomenon is noteworthy and may open novel avenues for CGRP receptor antagonist design.

Efficacy and mechanism of the antinociceptive effects of cannabidiol on acute orofacial nociception induced by Complete Freund’s Adjuvant in male Mus musculus mice

ObjectivesThe objectives were to investigate the efficacy and mechanisms of cannabidiol on orofacial nociception induced by Complete Freund’s Adjuvant (CFA) in male Mus musculus mice. DesignFor the study of efficacy, mice were divided into seven groups: sham; inflammation; and cannabidiol 0.5, 1, 3, 5, and 10 mg. For the study of mechanisms of cannabidiol, mice were divided into six groups: sham, inflammation, calcitonin gene-related peptide (CGRP) antagonist with and without cannabidiol, and vanilloid receptor 1 antagonist with and without cannabidiol. Spontaneous pain-like behaviors, trigeminal nociception, and trigeminal modulating activity were investigated. ResultsCFA injected in the right masseter muscle significantly induced spontaneous pain-like behaviors and the trigeminal nociceptive pathway. This effect was inhibited by injection of 1, 3, 5, and 10 mg of cannabidiol. The 50 % inhibitory concentration of cannabidiol on antinociception was found to be 3 mg/kg. In addition, there was no difference in spontaneous pain-like behaviors with vanilloid receptor 1 antagonist injected before treatment with cannabidiol compared to saline control. Reduced c-fos expression was observed in the trigeminal nucleus caudalis and periaqueductal gray in the group injected with CGRP antagonist before treatment with cannabidiol. ConclusionThe antinociceptive effects of cannabidiol induced by acute orofacial nociception is mediated by vanilloid receptor 1 but not by CGRP. Cannabidiol can act with peripheral nonpeptidergic neurons and can be used as an alternative drug or as a synergistic medication in pain treatment.

Elucidating the Ability of CGRP to Modulate Microvascular Events in Mouse Skin.

Oedema formation and polymorphonuclear leukocyte (neutrophil) accumulation are involved in both acute and chronic inflammation. Calcitonin gene-related peptide (CGRP) is a sensory neuropeptide that is released from stimulated sensory nerves. CGRP is a potent vasodilator neuropeptide, especially when administered to the cutaneous microvasculature, with a long duration of action. Here, we have investigated the ability of vasodilator amounts of CGRP to modulate oedema formation and neutrophil accumulation induced in the cutaneous microvasculature of the mouse. To learn more about the mechanism of action of endogenous CGRP, we have investigated the response to the inflammatory stimulants tumour necrosis factor alpha (TNFα) and carrageenan in three different murine models: a model where sensory nerves were depleted by resiniferatoxin (RTX); a pharmacological method to investigate the effect of a selective CGRP receptor antagonist; and a genetic approach using wildtype (WT) and αCGRP knockout (KO) mice. Our results show that exogenous CGRP potentiates oedema formation induced by substance P (SP) and TNFα. This is further supported by our findings from sensory nerve-depleted mice (in the absence of all neuropeptides), which indicated that sensory nerves are involved in mediating the oedema formation and neutrophil accumulation induced by TNFα, and also carrageenan in cutaneous microvasculature. Furthermore, endogenous CGRP was shown to contribute to this inflammatory response as carrageenan-induced oedema formation is attenuated in WT mice treated with the CGRP receptor antagonist, and in αCGRPKO mice. It is therefore concluded that CGRP can contribute to inflammation by promoting oedema formation in skin, but this response is dependent on the pro-inflammatory stimulus and circumstance.

Rimegepant for the treatment of migraine.

Migraine is a common form of primary headache, affecting up to 1 in every 6 Americans. The pathophysiology is an intricate interplay of genetic factors and environmental influence and is still being elucidated in ongoing studies. The trigeminovascular system is now known to have a significant role in the initiation of migraines, including the release of pain mediators such as CGRP and substance P. Traditional treatment of migraine is usually divided into acute and preventive treatment. Acute therapy includes non-specific therapy, such as NSAIDs and other analgesics, which may provide relief in mild to moderate migraines. 5-HT1 agonists may provide relief in severe migraine, but are not universally effective and carry a significant side-effect profile with frequent redosing requirement. Prophylactic therapy may reduce the occurrence of acute migraine attacks in selected patients, but does not completely eliminate it. More recently, CGRP antagonism has been studied and shown to be effective in both abortion and prevention of migraine. Novel medications, targeting CGRP, divide into CGRP antibodies and receptor antagonists (gepants). Rimegepant, a second-generation gepant, has shown efficacy in several clinical trials in treating acute migraine. Ongoing trials are also evaluating its role in migraine prophylaxis, and results are promising. It is also generally safer for use than existing options, does not appear to increase the chance of developing chronic migraines, and carries a very tolerable side effects profile. It is a part of a growing arsenal in migraine treatment, and may present the silver bullet for treatment of this disease.

Inpatient Constipation Among Migraine Patients Prescribed Anti-calcitonin Gene-Related Peptide Monoclonal Antibodies and Standard of Care Antiepileptic Drugs: A Retrospective Cohort Study in a United States Electronic Health Record Database.

Erenumab, an anti-calcitonin gene-related peptide (CGRP) receptor monoclonal antibody (mAb), was approved by the US Food and Drug Administration in May 2018. Constipation with serious complications was added to the Warning and Precautions section in the erenumab Prescribing Information in October 2019 after events were observed during post-marketing surveillance. We aimed to assess and compare the risk of inpatient constipation, and, separately, inpatient constipation with serious complications, among patients with migraine treated with CGRP mAbs and standard of care antiepileptic drugs (AEDs). Within Optum's Electronic Health Record Research Database, patients with migraine who initiated erenumab, other CGRP mAbs, and AEDs were identified from May 2018 through March 2020. Erenumab initiators were propensity score-matched separately to initiators of other CGRP mAbs and AEDs. Incident inpatient constipation events, and serious complications, were identified using multiple risk windows for outcome assessment (30-, 60-, 90-day risk windows, and all available follow-up). Odds ratios (ORs) were calculated comparing inpatient constipation risk among matched erenumab initiators relative to comparators. We identified 17,902 erenumab, 13,404 other CGRP mAb, and 49,497 AED initiators who met study criteria. Among matched initiators, the risk of inpatient constipation was 0.46% (95% confidence interval (CI) 0.35-0.60) for erenumab and 0.44% (95%CI 0.33-0.58) for other CGRP mAbs within the 90-day risk window, with a corresponding OR of 1.06 (95%CI 0.72-1.55). Among matched erenumab and AED initiators, inpatient constipation risk was 0.53% (95%CI 0.42-0.66) and 0.76% (95%CI 0.62-0.92), respectively, and the OR was 0.69 (95%CI 0.51-0.94). Few serious complications were observed. Patients initiating erenumab had similar risk of inpatient constipation within 90days of treatment initiation versus patients initiating other CGRP mAbs, and lower risk versus patients initiating AEDs. These findings provide context to events observed during post-marketing surveillance.

Blood Pressure in Patients With Migraine Treated With Monoclonal Anti-CGRP (Receptor) Antibodies: A Prospective Follow-up Study.

Anti-calcitonin gene-related peptide (CGRP) (receptor) antibodies are approved as preventive treatment for migraine. Recent concerns have been raised after a retrospective analysis of postmarketing case reports of elevated blood pressure (BP) associated with erenumab. In this prospective follow-up study, we aimed to assess the safety regarding BP in a real-world setting. All people with migraine who were treated with erenumab and fremanezumab at the Leiden Headache Center between January 2019 and January 2021 were included. BP measurements were collected from baseline (T0) until 12 months of follow-up, with a 3-month interval (T1-T4). Mixed linear models were fitted with time as a fixed effect and the patient as a random effect. Both systolic and diastolic BP were increased at all time points T1-T4 compared with T0 (p < 0.001). The maximum estimated increase in the mean systolic BP was 5.2 mm Hg (95% CI 3.1-7.5). The maximum estimated increase in the mean diastolic BP was 3.5 mm Hg (95% CI 2.0-4.9). In the erenumab group (n = 109), both systolic and diastolic BP were increased at all time points compared with T0 (all p < 0.001). For fremanezumab (n = 87), systolic but not diastolic BP was increased compared with T0 at T1 (p = 0.006) and T2 (p = 0.004). Four patients (3.7%) with normal BP at T0 required antihypertensive treatment after erenumab was started. The mean systolic and diastolic BP increased after anti-CGRP (receptor) antibodies were started. The majority of patients remained within the normal BP limits, but some patients required antihypertensive treatment. Physicians should be aware that people with migraine may be at risk of developing hypertension when treated with anti-CGRP (receptor) antibodies, and this should be added to (inter)national treatment guidelines. This study provides Class III evidence that anti-CGRP (receptor) antibodies increase BP when used to treat patients with migraine.

S539 Systematic Review and Meta-Analysis of the Prevalence of Constipation and Nausea Among Adults Using Calcitonin Gene-Related Peptide (CGRP) Inhibitors for Preventative Treatment of Cluster Headache or Migraine

Introduction: Constipation and nausea are frequently encountered medication-associated side effects. Calcitonin gene-related peptide (CGRP) inhibitor use may be potential cause of constipation and nausea, but the magnitude of this impact in patients with cluster headaches or migraines has not been well characterized. Methods: We conducted a systematic review using PUBMED and ClinicalTrials.Gov to identify randomized, placebo-controlled clinical trials using anti-CGRP antibodies or CGRP receptor antagonists for the prevention of cluster headaches or chronic migraine. We extracted data including CGRP inhibitor dose, dose frequency, and the reported proportions of patients in these trials with constipation and nausea. We compared the prevalence of these symptoms in those on medication to those on placebo, using two-tailed paired t-tests. The risk of a specific adverse event was assessed using odds ratios with 95% confidence intervals. Results: We identified an initial pool of 449 studies to which we applied a priori criteria to yield 27 studies for nausea and 15 studies for constipation analyses. In the anti-CGRP antibody-treated group, the pooled prevalence of constipation was 2.69% (N=3,574) and nausea was 2.03% (N=9,231), compared with 1.39% (N=4,520, p=0.004) and 2.47% (N=11,680, p=0.0095) in placebo-treated groups, respectively. In the CGRP receptor antagonist-treated group, the prevalence of constipation was 5.20% (N=1,847) and nausea was 6.04% (N=1,689), compared to 1.46% (N=1,852, p=0.002) and 3.05% (N=1,967, p=0.0001) in placebo-treated groups, respectively. CGRP receptor antagonist use demonstrated greater risks of constipation (OR=3.71 [2.41, 5.71], p< 0.0001) and nausea (OR=2.04 [1.48, 2.83], p< 0.0001) than anot-CGRP antibody use (constipation: OR=1.96 [1.41, 2.72], p=0.0001; nausea: OR=0.82, [0.68, 0.99], p = 0.0343). Anti-CGRP antibody use did not appear to be associated with an increased risk of nausea. Conclusion: Constipation and nausea are associated with CGRP inhibitor use in those with cluster headache or migraine. With the increased prevalence of CGRP inhibitor use, CGRP inhibitor-associated constipation and nausea cases could grow substantially. Gastroenterologists should consider CGRP inhibitor use as a medication-induced cause of nausea and constipation. CGRP receptor antagonist use is associated with higher rates of these gastrointestinal side effects than the use of anti-CGRP antibodies.

Prevention of Migraine

Migraine, a primary headache disorder is a chronic and complex neurological disease that affects millions of people worldwide, impacting their quality of life. It is one of the most common reasons why individuals seek the advice of their physician, and is one of the most common referrals seen in the offices of general neurologists and headache specialists. In the past decade, there has been robust research on not only the pathophysiology of migraine but in the efforts to treat and, importantly, prevent. The introduction of calcitonin gene related peptide antagonists (CGRP-A) have opened new doors for preventive treatment options. OnabotulinumtoxinA (BoNTA) has remained a staple in the treatment of chronic migraine with data emerging with combination therapy. Neurostimulation has offered additional nonpharmacologic approaches to migraine treatment. In addition to lifestyle and behavioral modifications, these have changed the landscape of migraine prevention.

Improving distress perception and mutuality in migraine caregivers after 6months of galcanezumab treatment.

This prospective cohort, real-life study aimed to evaluate whether galcanezumab, a monoclonal antibody anti-calcitonin gene-related peptide (CGRP) ligand, can reduce caregivers' distress and improve their mutuality with patients. Migraine is a highly disabling chronic disease that negatively impacts patients' and often their relatives' lives, occurring during an active phase of life with direct consequences on leisure- and work-related activities. The figure of caregiver is crucial in several neurological conditions but poorly accounted for in migraine care so far. Studies on monoclonal antibodies against the CGRP pathway, recently introduced as migraine-preventive treatments, demonstrated that they significantly reduce migraine frequency and disability in the first weeks of treatment. Consecutive patient-caregiver dyads were evaluated at baseline and after 6months of treatment with galcanezumab (V6) at our headache center from September 2020 to September 2021. Enrolled patients were requested to report their monthly migraine days, monthly intake of acute medications, attack pain intensity (on the Numeric Rating Scale), concomitant preventives, and disability questionnaires (Headache Impact Test, Migraine Disability Assessment). Each dyad filled in the Mutuality Scale to check their reciprocity; moreover, the Relatives' Stress Scale was used to detect caregivers' distress. We enrolled 27 patient-caregiver dyads. At 6months, migraine burden significantly improved with reductions in monthly migraine days (falling from 14.8 [SD=4.8] days by 10.3 [SD=4.8] days; 95% CI: 8.4, 12.2; p< 0.001) and Migraine Disability Assessment scores (lowering from 83.6 [SD=46.7] by 71.5 points [SD=49.3]; 95% CI: 51.2, 91.9; p< 0.001). From baseline to month 6, the caregiver Relatives' Stress Scale score significantly decreased (falling from 20.7 [SD=13.7] by 6.5 [SD=14.1] points; 95% CI: 0.8, 12.2; p= 0.027), while the Mutuality Scale's caregiver total score increased (from 3.04 [SD=0.61] by 0.29 [SD=0.49] points; 95% CI: -0.508, -0.064; p= 0.014). Our findings preliminarily demonstrated that patients' migraine improvement after 6months of galcanezumab treatment could be favorably perceived by caregivers, significantly reducing their distress with better reciprocity within the dyad.