A randomized, placebo-controlled study of the effects of telcagepant on exercise time in patients with stable angina

Metabolic and toxicological considerations regarding CGRP mAbs and CGRP antagonists to treat migraine in COVID-19 patients: a narrative review

INTRODUCTION

Migraine pharmacological therapies targeting calcitonin gene-related peptide (CGRP), including monoclonal antibodies and gepants, have shown clinical effect and optimal tolerability. Interactions between treatments of COVID-19 and CGRP-related drugs have not been reviewed.

AREAS COVERED

An overview of CGRP, a description of the characteristics of each CGRP-related drug and its response predictors, COVID-19 and its treatment, the interactions between CGRP-related drugs and COVID-19 treatment, COVID-19 and vaccination-induced headache, and the neurological consequences of Covid-19.

EXPERT OPINION

Clinicians should be careful about using gepants for COVID-19 patients, due to the potential drug interactions with drugs metabolized via CYP3A4 cytochrome. In particular, COVID-19 treatment (especially nirmatrelvir packaged with ritonavir, as Paxlovid) should be considered cautiously. It is advisable to stop or adjust the dose (10 mg atogepant when used for episodic migraine) of gepants when using Paxlovid (except for zavegepant). CGRP moncolconal antibodies (CGRP-mAbs) do not have drug - drug interactions, but a few days' interval between a COVID-19 vaccination and the use of CGRP mAbs is recommended to allow the accurate identification of the possible adverse effects, such as injection site reaction. Covid-19- and vaccination-related headache are known to occur. Whether CGRP-related drugs would be of benefit in these circumstances is not yet known.

Calcitonin Gene-Related Peptide Systemic Effects: Embracing the Complexity of Its Biological Roles-A Narrative Review

The calcitonin gene-related peptide (CGRP) is a neuropeptide widely distributed throughout the human body. While primarily recognized as a nociceptive mediator, CGRP antagonists are currently utilized for migraine treatment. However, its role extends far beyond this, acting as a regulator of numerous biological processes. Indeed, CGRP plays a crucial role in vasodilation, inflammation, intestinal motility, and apoptosis. In this review, we explore the non-nociceptive effects of CGRP in various body systems, revealing actions that can be contradictory at times. In the cardiovascular system, it functions as a potent vasodilator, yet its antagonists do not induce arterial hypertension, suggesting concurrent modulation by other molecules. As an immunomodulator, CGRP exhibits intriguing complexity, displaying both anti-inflammatory and pro-inflammatory effects. Furthermore, CGRP appears to be involved in obesity development while paradoxically reducing appetite. A thorough investigation of CGRP's biological effects is crucial for anticipating potential side effects associated with its antagonists' use and for developing novel therapies in other medical fields. In summary, CGRP represents a neuropeptide with a complex systemic impact, extending well beyond nociception, thus offering new perspectives in medical research and therapeutics.

A Pharmacological Review of Calcitonin Gene-Related Peptide Biologics and Future Use for Chronic Pain

Calcitonin gene-related peptide (CGRP) antagonist medications have become the mainstay of acute and chronic migraine management in the outpatient setting and look to become more widely utilized by clinicians once the medications become available in generic form. However, their role in practice has remained limited to the treatment of migraines despite the ubiquitous presence of the molecule throughout the body. The literature surrounding expansion of the utility of these medications is limited; however, there have been several promising publications, and further studies are in the process to quantify their utility in the treatment of other pain-related disorders. This is a qualitative review of the current literature surrounding CGRP, particularly in relation to the treatment of non-migraine pain conditions, and looks to suggest potential utility in the field of chronic pain.

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.

Real world considerations for newly approved CGRP receptor antagonists in migraine care

INTRODUCTION

Migraine is the leading cause of years lived with disability in people under 50 . Electrophysiological phenomena at the basis of prodromal and headache attack phases and of chronification processes involve calcitonin-gene related peptide (CGRP) as a fundamental player become a game changer of migraine pharmacotherapy.Areas covered: The purpose of the present review is to retrace fundamental stages of CGRP from its discovery to the role in migraine pathogenesis and therapy to underscore the change of paradigm offered by the newly approved small molecules to antagonize CGRP receptor, the gepants. In particular, the development of this new class is gone over from the initial synthesis of C-terminus truncated CGRP antagonists to the development of the first generation of gepants ending with Zavegepant that can be considered the third generation.Expert opinion: The history of CGRP in migraine draws the successful road to follow for key signaling pathways of modulation of nociceptive facilitation by diencephalic and brainstem nuclei, including dopaminergic neurotransmission, orexin A and the large-conductance calcium-activated potassium (BK_Ca) and ATP-sensitive potassium (K_ATP) channels also investigating the potential of essential oils and the role of polymorphisms. Real-world post marketing long-term data are needed for gepants.

Migraine

Migraine is a common, chronic, disorder that is typically characterized by recurrent disabling attacks of headache and accompanying symptoms, including aura. The aetiology is multifactorial with rare monogenic variants. Depression, epilepsy, stroke and myocardial infarction are comorbid diseases. Spreading depolarization probably causes aura and possibly also triggers trigeminal sensory activation, the underlying mechanism for the headache. Despite earlier beliefs, vasodilation is only a secondary phenomenon and vasoconstriction is not essential for antimigraine efficacy. Management includes analgesics or NSAIDs for mild attacks, and, for moderate or severe attacks, triptans or 5HT_1B/1D receptor agonists. Because of cardiovascular safety concerns, unreliable efficacy and tolerability issues, use of ergots to abort attacks has nearly vanished in most countries. CGRP receptor antagonists (gepants) and lasmiditan, a selective 5HT1_F receptor agonist, have emerged as effective acute treatments. Intramuscular onabotulinumtoxinA may be helpful in chronic migraine (migraine on ≥15 days per month) and monoclonal antibodies targeting CGRP or its receptor, as well as two gepants, have proven effective and well tolerated for the preventive treatment of migraine. Several neuromodulation modalities have been approved for acute and/or preventive migraine treatment. The emergence of new treatment targets and therapies illustrates the bright future for migraine management.

Calcitonin gene related peptide in migraine: current therapeutics, future implications and potential off-target effects

Migraine is the second largest cause of years lost to disability globally among all diseases, with a worldwide prevalence over 1 billion. Despite the global burden of migraine, few classes of therapeutics have been specifically developed to combat migraine. After 30 years of translational research, calcitonin gene-related peptide (CGRP) inhibitors have emerged as a promising new tool in the prevention of migraine. Like all new therapeutics; however, we have limited real-world experience and CGRP has several known systemic actions that warrant consideration. This article provides a narrative review of the evidence for CGRP antagonists and summarises the known and potential side effects that should be considered.

Novel Therapies in Acute Migraine Management: Small-Molecule Calcitonin Gene-Receptor Antagonists and Serotonin 1F Receptor Agonist

OBJECTIVE

To review the efficacy, safety, and cost of 3 newly approved agents-ubrogepant, lasmiditan, and rimegepant-representing 2 therapeutic classes, calcitonin gene-related peptide (CGRP) receptor antagonist and serotonin 1F (5-HT1F) agonists, for the acute treatment of migraine with or without aura.

DATA SOURCES

The Institute of Health US National Library of Medicine Clinical Trials, PubMed, and Cochrane databases were queried. Abstracts, journal articles, and other relevant sources published or present were reviewed. Search terms included the following: ubrogepant, MK-1602, Ubrelvy®, rimegepant, Nurtec®, BHV-3000, BMS-927711, lasmiditan, Reyvow®, LY573144.

STUDY SELECTION AND DATA EXTRACTION

Relevant English-language articles from June 30, 2010, to August 31, 2020, were evaluated and included in the narrative.

DATA SYNTHESIS

CGRP receptor antagonists, ubrogepant and rimegepant, achieved 2-hour pain freedom and freedom from the most bothersome migraine symptom (MBS) at 2 hours. Both agents were well tolerated, with adverse effects similar to placebo. Lasmiditan, a 5-HT1F receptor antagonist, also improved 2-hour pain freedom and freedom from the MBS at 2 hours. Lasmiditan is associated with dizziness, paresthesia, somnolence, nausea, fatigue, and lethargy.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Ubrogepant, rimegepant, and lasmiditan represent a new and exciting chapter in acute migraine therapy. To date, no head-to-head studies have compared these agents with the triptans. Ubrogepant and lasmiditan are effective in triptan nonresponders. None of the 3 agents is contraindicated in cardiovascular disease, unlike the triptans.

CONCLUSIONS

Based on available data, ubrogepant, rimegepant, and lasmiditan should be reserved as second-line therapy and may be safe in patients with cardiovascular risk. Lasmiditan's adverse effect profile may limit its use.

Calcitonin Gene-Related Peptide Protects Against Cardiovascular Dysfunction Independently of Nitric Oxide In Vivo

[Figure: see text].

Gepants, calcitonin-gene-related peptide receptor antagonists: what could be their role in migraine treatment?

PURPOSE OF REVIEW

Migraine is the second leading cause of years lived with disability after back pain. Poor tolerability, contraindications, drug-drug interactions and efficacy limited to a subpopulation make new approaches necessary for the acute and preventive treatment of migraine. The study of the calcitonin-gene-related peptide (CGRP) pathway over the last decades is a good example of translational medicine leading to directed therapies for patients.

RECENT FINDINGS

After some of the first-generation CGRP receptor antagonists, gepants, were not fully developed because of hepatotoxicity, the second generation of gepants have shown efficacy, safety and tolerability in recent clinical trials.

SUMMARY

Both rimegepant and ubrogepant have published positive randomized placebo-controlled clinical trials data. Vazegepant is the first intranasal gepant for the acute treatment of migraine and has announced a positive phase II/III study. Daily rimegepant use has preliminary data to suggest efficacy. Atogepant has shown efficacy in migraine prevention in a phase II/III study. Most importantly, hepatotoxicity has not been reported in specifically designed phase I studies or long-term extension studies, with rimegepant or ubrogepant, or in a preventive study with atogepant. Given the preventive effect, it seems likely that gepants will not lead to medication overuse headache. They will likely have no cardiovascular warnings. Because of the particular benefit gepants may represent for these groups of patients, specific studies in patients with medication overuse headache, as well as those with comorbid cardiovascular diseases, would be of considerable interest.

Update on Calcitonin Gene-Related Peptide Antagonism in the Treatment of Migraine

The discovery of calcitonin gene-related peptide (CGRP) and its role in migraine has promoted a new era in migraine treatment: CGRP antagonism. Two classes of medications are currently available: small molecules targeting the CGRP receptor and monoclonal antibodies targeting the CGRP receptor or CGRP ligand. The revolution of these medications is represented by blurring the borders between acute and preventive treatments, episodic and chronic migraine, naïve and refractory patients and even between migraine and other headache disorders.

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

Objective

Calcitonin gene–related peptide (CGRP) pathway inhibitors are emerging treatments for migraine. CGRP‐mediated vasodilation is, however, a critical rescue mechanism in ischemia. We, therefore, investigated whether gepants, small molecule CGRP receptor antagonists, worsen cerebral ischemia.

Methods

Middle cerebral artery was occluded for 12 to 60 minutes in mice. We compared infarct risk and volumes, collateral flow, and neurological deficits after pretreatment with olcegepant (single or 10 daily doses of 0.1–1mg/kg) or rimegepant (single doses of 10–100mg/kg) versus vehicle. We also determined their potency on CGRP‐induced relaxations in mouse and human vessels, in vitro.

Results

Olcegepant (1mg/kg, single dose) increased infarct risk after 12‐ to 20‐minute occlusions mimicking transient ischemic attacks (14/19 vs 6/18 with vehicle, relative risk = 2.21, p < 0.022), and doubled infarct volumes (p < 0.001) and worsened neurological deficits (median score = 9 vs 5 with vehicle, p = 0.008) after 60‐minute occlusion. Ten daily doses of 0.1 to 1mg/kg olcegepant yielded similar results. Rimegepant 10mg/kg increased infarct volumes by 60% after 20‐minute ischemia (p = 0.03); 100mg/kg caused 75% mortality after 60‐minute occlusion. In familial hemiplegic migraine type 1 mice, olcegepant 1mg/kg increased infarct size after 30‐minute occlusion (1.6‐fold, p = 0.017). Both gepants consistently diminished collateral flow and reduced reperfusion success. Olcegepant was 10‐fold more potent than rimegepant on CGRP‐induced relaxations in mouse aorta.

Interpretation

Gepants worsened ischemic stroke in mice via collateral dysfunction. CGRP pathway blockers might thus aggravate coincidental cerebral ischemic events. The cerebrovascular safety of these agents must therefore be better delineated, especially in patients at increased risk of ischemic events or on prophylactic CGRP inhibition. ANN NEUROL 2020;88:771–784

Blocking the CGRP Pathway for Acute and Preventive Treatment of Migraine: The Evolution of Success

The pivotal role of calcitonin gene-related peptide (CGRP) in migraine pathophysiology was identified over 30 years ago, but the successful clinical development of targeted therapies has only recently been realized. This Perspective traces the decades long evolution of medicinal chemistry required to advance small molecule CGRP receptor antagonists, also called gepants, including the current clinical agents rimegepant, vazegepant, ubrogepant, and atogepant. Providing clinically effective blockade of CGRP signaling required surmounting multiple challenging hurdles, including defeating a sizable ligand with subnanomolar affinity for its receptor, designing antagonists with an extended confirmation and multiple pharmacophores while retaining solubility and oral bioavailability, and achieving circulating free plasma levels that provided near maximal CGRP receptor coverage. The clinical efficacy of oral and intranasal gepants and the injectable CGRP monoclonal antibodies (mAbs) are described, as are recent synthetic developments that have benefited from new structural biology data. The first oral gepant was recently approved and heralds a new era in the treatment of migraine.

Evaluation of Cardiovascular Outcomes in Adult Patients With Episodic or Chronic Migraine Treated With Galcanezumab: Data From Three Phase 3, Randomized, Double-Blind, Placebo-Controlled EVOLVE-1, EVOLVE-2, and REGAIN Studies

OBJECTIVE

Blood pressure (BP), pulse, electrocardiogram (ECG), and clinical cardiovascular (CV) outcomes in patients with episodic or chronic migraine treated for up to 6 months with galcanezumab compared to placebo were evaluated.

BACKGROUND

Calcitonin gene-related peptide, a potent microvascular vasodilator, has a hypothesized protective role in CV health. Increased CV risks have been reported in patients with migraine.

METHODS

In 2 similarly designed episodic migraine 6-month studies and 1 chronic migraine 3-month study, data from patients randomized (1:1:2) to subcutaneous injection of galcanezumab 120 mg/month (following initial 240 mg loading dose) or 240 mg/month or placebo were pooled. Treatment comparisons for cardiovascular treatment-emergent adverse events (CV TEAE) and categorical and mean changes in BP, pulse, and ECG were evaluated using the Cochran-Mantel-Haenszel test. Mean changes from baseline in BP, pulse, and ECG were evaluated using the analysis of covariance model.

RESULTS

Overall, among galcanezumab 120 mg (n = 705) and 240 mg (n = 730), and placebo (n = 1451) groups, the percentage of patients reporting ≥1 CV TEAE was low and was similar between the galcanezumab 120 mg (2.6%; odds ratio [OR] = 0.9; 95% confidence interval [CI]: 0.5,1.5) and galcanezumab 240 mg (3.3%; OR = 1.1; 95% CI: 0.7,1.9), and placebo (2.9%) groups. The frequency of any individual CV TEAE, broad or narrow term, was ≤1.4%. The CV-related serious adverse events that occurred in the galcanezumab 240 mg group (n = 3; acute myocardial infarction, pulmonary embolism, and transient ischemic attack) and placebo group (n = 3; pulmonary embolism, deep vein thrombosis, and myocardial infarction) were not considered treatment related. Four placebo- and 1 galcanezumab-treated patient discontinued due to a CV TEAE. Least squares mean and categorical changes from baseline in BP, pulse, and QT interval corrected using Fridericia's correction were similar across treatment groups.

CONCLUSIONS

In this 6-month treatment trial, the percentages of galcanezumab- and placebo-treated patients that reported CV TEAEs or serious adverse events were low and similar between groups with few discontinuations. Thus, no clinically meaningful treatment group differences were observed for changes in BP, pulse, or ECG parameters. Additional longer-term studies in a broader and larger cohort are required to better characterize CV safety.

Targeting calcitonin gene-related peptide: a new era in migraine therapy

Migraine is one of the most prevalent and disabling diseases worldwide, but until recently, few migraine-specific therapies had been developed. Extensive basic and clinical scientific investigation has provided strong evidence that the neuropeptide calcitonin gene-related peptide (CGRP) has a key role in migraine. This evidence led to the development of small molecule CGRP receptor antagonists and monoclonal antibodies targeting either CGRP or its receptor. Clinical trials investigating these therapies have consistently shown statistically significant efficacy for either the acute or preventive treatment of migraine. No serious safety or tolerability issues have been identified in the trials of the monoclonal antibody therapies. Although the appropriate place of these new migraine-specific therapies relative to other available acute and preventive treatments remains to be determined, a growing body of evidence shows that therapeutic approaches targeting CGRP have the potential to transform the clinical management of migraine.

Novel Medications for the Treatment of Migraine

OBJECTIVE

To describe the new classes of medication for headache management and their roles in clinical practice.

BACKGROUND

Calcitonin gene-related peptide (CGRP) is a key component in the underlying pathophysiology of migraine. Research focused on targeting CGRP for headache treatment has led to the development of entirely new classes of medications - the gepants and the CGRP monoclonal antibodies (mAbs) - for both acute and preventive treatment. A third class, the ditans, is being developed to target the 5-HT1F receptor to provide acute treatment without vasoconstrictive effects.

METHODS

This article reviews the pathophysiology of migraine that has led to these new pharmacologic developments. Available information from randomized controlled trials, abstracts, press releases, and relevant preclinical studies is summarized for each class of medications.

RESULTS

At the time of this writing, one ditan has been submitted to the U.S. Food and Drug Administration (FDA) for approval. One gepant is anticipated to be submitted within the first quarter of 2019, and others are in clinical trials. Three CGRP mAbs have been FDA approved and are now available in clinical practice, and a fourth was submitted in the first quarter of 2019.

CONCLUSIONS

The development of new migraine-specific classes of medications provides more treatment options for both acute and preventive treatment of migraine.

Getting to the Heart of the Matter: Migraine, Triptans, DHE, Ditans, CGRP Antibodies, First/Second-Generation Gepants, and Cardiovascular Risk

PREMISE

The science of migraine pathophysiology has advanced significantly since the 1930's. Imaging techniques, neurochemical analysis, clinical trials, and the clinical experience of providers treating migraine patients have not only sharpened our understanding of the disease, but have also led to the development of novel neural-based targets. Targeted therapies such as calcitonin gene-related peptide (CGRP) antibodies and "Second Generation" CGRP receptor antagonists (Gepants) have not only demonstrated efficacy, but have not resulted in any significant cardiovascular nor other serious adverse events. "First Generation" Gepants were associated with liver toxicity.

PROBLEM

Triptans and dihydroergotamine (DHE) are contraindicated in patients with hemiplegic and basilar migraine based on theories of migraine pathophysiology from the 1930s. While our understanding of migraine has evolved substantially, perceived concerns of safety from almost a century ago continue to preclude their use in certain patient populations.

POTENTIAL SOLUTION

While migraine aura was once thought to be primarily due to vasoconstriction, current evidence debunks this concept. For instance, hemiplegic migraine is the consequence of genetic mutations resulting in channelopathies without evidence of cerebral ischemia or infarction. Evidence of basilar artery constriction as postulated in basilar migraine is also lacking. This recognition has led the International Headache Society to rename basilar-type migraine to migraine with brainstem aura. The following discussion reviews current literature with respect to migraine as a neuronal disorder, as well as the published data on the safety of triptans, DHE, Ditans (a novel class of 5-HT_1f receptor agonists), CGRP antibodies, and Gepants.

A Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Effect of Erenumab on Exercise Time During a Treadmill Test in Patients With Stable Angina

Objective

To determine the potential impact of erenumab, a human anti‐calcitonin gene‐related peptide (CGRP) receptor monoclonal antibody, on total exercise time (TET), time to exercise‐induced angina, and ST depression in a double‐blind, placebo‐controlled study in patients with stable angina due to documented coronary artery disease.

Background

The relative importance of the CGRP receptor pathway during myocardial ischemia has not been established.

Methods

An exercise treadmill test was conducted following a single IV infusion of erenumab 140 mg or placebo. The primary endpoint was the change from baseline in exercise duration as measured by TET with a noninferiority margin of −90 seconds. Safety follow‐up visits occurred through week 12. Eighty‐eight participants were included in the analysis.

Results

LS mean (SE) change in TET was −2.9 [14.8] seconds in the erenumab group and 8.1 [14.4] seconds in placebo; adjusted mean (90% CI) treatment difference was −11.0 (–44.9, 22.9) seconds. The CI lower bound (–44.9 sec) did not reach pre‐defined non‐inferiority margin of −90 seconds, demonstrating that TET change from baseline in the erenumab group was non‐inferior to placebo. There was no difference in time to exercise‐induced angina in erenumab and placebo groups (median [90% CI] time of 500 [420, 540] vs 508 [405, 572] seconds; hazard ratio [90% CI]: 1.11 [0.73, 1.69], P = .69) or time to onset of ≥1 mm ST‐segment depression (median [90% CI] time of 407 [380, 443] vs 420 [409,480] seconds; hazard ratio [95% CI]: 1.14 [0.76, 1.69], P = .59). Adverse events were reported by 27% and 32% of patients in erenumab and placebo groups.

Conclusions

Erenumab did not adversely affect exercise time in a high cardiovascular risk population of patients, supporting that inhibition of the canonical CGRP receptor does not worsen myocardial ischemia.

Anti-CGRP and anti-CGRP receptor monoclonal antibodies as antimigraine agents. Potential differences in safety profile postulated on a pathophysiological basis

Calcitonin gene-related peptide (CGRP) is a peptide neurotransmitter with potent vasodilating properties. CGRP is believed to play a primary role in the pathogenesis of migraine. As such, CGRP and its receptors are obvious druggable targets for novel anti-migraine agents. While the development of small-molecule CGRP receptor antagonists started first, none of these agents is yet available in clinical practice. Conversely, both anti-CGRP and anti-CGRP receptor monoclonal antibodies (mABs) completed clinical development, and the first representatives of these 2 classes are available on the market. MABs are approved for prevention of migraine attacks in chronic or episodic migraine, involving long-term treatments. In light of the physiological role exerted by CGRP in the regulation of vascular tone, the potential risks of a long-term inhibition of CGRP functions raised diffuse concerns. These concerns were correctly addressed by the anti-CGRP receptor mABs erenumab with a 5-year open-label clinical trial; however, this study is currently ongoing and results are not yet available, leaving some uncertainty on the profile of erenumab long-term safety. Similar concerns can be raised with direct anti-CGRP mABs, which entrap the peptide preventing receptor activation. However, evidence exists that plasma CGRP is detectable in patients chronically treated with anti-CGRP mABs. Assuming that plasma CGRP is an indirect marker of peptide levels at the vascular receptor sites, such residual CGRP would maintain a physiological level of receptor stimulation, in spite of a well-established anti-migraine activity of the mABs. This might represent a potential advantage in the safety profile of anti-CGRP mABs, but it needs to be confirmed and expanded with data on free plasma CGRP.

Fremanezumab as a preventive treatment for episodic and chronic migraine

Introduction: The importance of calcitonin gene-related peptide (CGRP) in migraine pathogenesis is well established. Fremanezumab is a humanized IgG2a monoclonal antibody that binds to CGRP. Areas covered: In this paper, we review the development of fremanezumab, from early development into approval. The authors focus on the efficacy and safety of fremanezumab in both migraine stages. The authors highlight studies conducted in special populations and focus on unique aspects of its development, as well as on clinical pearls supported by the data. Expert opinion: Fremanezumab was shown to be effective in episodic and chronic migraine, with a monthly and quarterly dose of administration, as monotherapy and add-on therapy. As with other monoclonal antibodies, the anti-CGRP onset of action was remarkably quick, and the effect seems to be maintained over time. No overt safety concerns emerged from the clinical studies, although long-term surveillance is necessary.

Calcitonin Gene-Related Peptide Modulators - The History and Renaissance of a New Migraine Drug Class

Several lines of evidence pointed to an important role for CGRP in migraine. These included the anatomic colocalization of CGRP and its receptor in sensory fibers innervating pain-producing meningeal blood vessels, its release by trigeminal stimulation, the observation of elevated CGRP in the cranial circulation during migraine with normalization concomitant with headache relief by sumatriptan, and translational studies with intravenous (IV) CGRP that evoked migraine only in migraineurs. The development of small molecule CGRP receptor antagonists (CGRP-RAs) that showed clinical antimigraine efficacy acutely and prophylactically in randomized placebo-controlled clinical trials subsequently gave definitive pharmacological proof of the importance of CGRP in migraine. More recently, CGRP target engagement imaging studies using a CGRP receptor PET ligand [¹¹ C]MK-4232 demonstrated that there was no brain CGRP receptor occupancy at clinically effective antimigraine doses of telcagepant, a prototypic CGRP-RA. Taken together, these data indicated that (1) the therapeutic site of action of the CGRP-RAs was peripheral not central; (2) that IV CGRP had most likely evoked migraine through an action at sites outside the blood-brain barrier; and (3) that migraine pain was therefore, at least in part, peripheral in origin. The evolution of CGRP migraine science gave impetus to the development of peripherally acting drugs that could modulate CGRP chronically to prevent frequent episodic and chronic migraine. Large molecule biologic antibody (mAb) approaches that are given subcutaneously to neutralize circulating CGRP peptide (fremanezumab, galcanezumab) or block CGRP receptors (erenumab) have shown consistent efficacy and tolerability in multicenter migraine prevention trials and are now approved for clinical use. Eptinezumab, a CGRP neutralizing antibody given IV, shows promise in late stage clinical development. Recently, orally administered next-generation small molecule CGRP-RAs have been shown to have safety and efficacy in acute treatment (ubrogepant and rimegepant) and prevention (atogepant) of migraine, giving additional CGRP-based therapeutic options for migraine patients.

CGRP and migraine from a cardiovascular point of view: what do we expect from blocking CGRP?

Calcitonin gene-related peptide (CGRP) is a neuropeptide with a pivotal role in the pathophysiology of migraine. Blockade of CGRP is a new therapeutic target for patients with migraine. CGRP and its receptors are distributed not only in the central and peripheral nervous system but also in the cardiovascular system, both in blood vessels and in the heart. We reviewed the current evidence on the role of CGRP in the cardiovascular system in order to understand the possible short- and long-term effect of CGRP blockade with monoclonal antibodies in migraineurs.

In physiological conditions, CGRP has important vasodilating effects and is thought to protect organs from ischemia. Despite the aforementioned cardiovascular implication, preventive treatment with CGRP antibodies has shown no relevant cardiovascular side effects. Results from long-term trials and from real life are now needed.

European headache federation guideline on the use of monoclonal antibodies acting on the calcitonin gene related peptide or its receptor for migraine prevention

BACKGROUND AND AIM

Monoclonal antibodies acting on the calcitonin gene-related peptide or on its receptor are new drugs to prevent migraine. Four monoclonal antibodies have been developed: one targeting the calcitonin gene-related peptide receptor (erenumab) and three targeting the calcitonin gene-related peptide (eptinezumab, fremanezumab, and galcanezumab). The aim of this document by the European Headache Federation (EHF) is to provide an evidence-based and expert-based guideline on the use of the monoclonal antibodies acting on the calcitonin gene-related peptide for migraine prevention.

METHODS

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

RESULTS

We found low to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in patients with episodic migraine and medium to high quality of evidence to recommend erenumab, fremanezumab, and galcanezumab in patients with chronic migraine. For several clinical questions, there was not enough evidence to provide recommendations using the GRADE approach and recommendations relied on experts' opinion.

CONCLUSION

Monoclonal antibodies acting on the calcitonin gene-related peptide are new drugs which can be recommended for migraine prevention. Real life data will be useful to improve the use of those drugs in clinical practice.

CGRP Discovery and Timeline

Calcitonin gene-related peptide (CGRP) was discovered over about 35 years ago through molecular biological techniques. Its activity as a vasodilator and the proposal that it was involved in pain processing were then soon established. Today, we are in the interesting situation of having the approval for the clinical use of antagonists and antibodies that have proved to block CGRP activities and benefit migraine. Despite all, there is still much to learn concerning the relevance of the vasodilator and other activities as well as further potential applications of CGRP agonists and blockers in disease. This review aims to discuss the history and present knowledge and to act as an introductory chapter in this volume.

From LBR-101 to Fremanezumab for Migraine

Calcitonin gene-related peptide (CGRP) is a neuropeptide of importance in migraine pathogenesis. Its central role in migraine was proven pharmacologically by the development of CGRP receptor antagonists. Monoclonal antibodies targeting CGRP or its receptor are effective in the preventive treatment of episodic and chronic migraine and are considered potential breakthroughs in their treatment. Fremanezumab (previously known as TEV-48125, LBR-101, or RN-307) is a humanized IgG2a monoclonal antibody that binds to CGRP. The development of this antibody validated the role of CGRP in chronic migraine and the drug has been recently approved in the US by the FDA, while it continues to be reviewed by other regulatory agencies. Herein we provide an in-depth review of its development. We start by summarizing its in vitro and in vivo pharmacology, and the phase I studies. We then review the late-stage clinical development, with a focus on its efficacy, safety, similarities, and uniqueness relative to other CGRP antibodies. We close by discussing lessons learned on the mechanisms of migraine and areas for future development and exploration.

CGRP – a target for acute therapy in migraine: Clinical data

Background

A better understanding of the mechanisms underlying the migraine attack has reinforced the concept that migraine is a complex brain disease, and has paved the way for the development of new migraine specific acute treatments. In recent years, targeting the calcitonin gene-related peptide and its receptors has been one of the most promising pharmacological strategies for both acute and preventive treatment of migraine.

Findings

Randomized double-blind placebo-controlled trials have demonstrated the superiority of small molecule calcitonin gene-related peptide receptor antagonists (gepants) over placebo in treating acute migraine attacks measured as the two-hour pain free endpoint. Gepants also improved migraine associated symptoms, such as nausea, photophobia and phonophobia. Two of the class have had their development stopped because of hepatotoxicity, which is emerging as being due to metabolites. Gepants have a good tolerability and can be safely used in patients with stable cardiovascular disease.

Conclusion

Exciting results have been obtained targeting the calcitonin gene-related peptide pathway to abort acute migraine attacks, thus reinforcing the relevance of mechanism-based treatments specific for migraine.

Calcitonin gene-related peptide monoclonal antibodies for migraine prevention: comparisons across randomized controlled studies

PURPOSE OF REVIEW

The results of phase 2 randomized controlled trials for the prevention of episodic and chronic migraine demonstrating the efficacy and safety of four mAbs targeting the calcitonin gene-related peptide (CGRP) pathway [ALD403 (eptinezumab), AMG334 (erenumab), LY2951742 (galcanezumab) and TEV48125 (fremanezumab)] have been published recently, and phase 3 trials are in process. This development will change headache management fundamentally. We aim to summarize and compare the phase 2 data.

RECENT FINDINGS

The change from baseline in the number of migraine days at the end of treatment in high-frequency episodic migraine was -1 (at weeks 5-8), -1.1 (at weeks 9-12), -1.2 (at weeks 9-12) and -2.6 (at weeks 9-12) days for ALD403, AMG344, LY2951742 and TEV48125 (225 mg), respectively. Number needed to treats for responders and odds ratio for any adverse event were 4.7, 6.2, 4.0 and 4.0 and 1.09, 0.96, 1.07 and 1.05, respectively.

SUMMARY

All four CGRP antibodies display comparable efficacy that does not differ significantly from that of the currently available oral antimigraine drugs. However, their safety and tolerability profiles as well as low frequency of administration looks promising but remains to be verified in long-term and large-scale trials. Considerations related to pregnancy, risk for cardiovascular effects and cost are subject for further evaluation.

Safety and efficacy of AMG 334 for prevention of episodic migraine: a randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND

The calcitonin gene-related peptide (CGRP) pathway is a promising target for preventive therapies in patients with migraine. We assessed the safety and efficacy of AMG 334, a fully human monoclonal antibody against the CGRP receptor, for migraine prevention.

METHODS

In this multicentre, randomised, double-blind, placebo-controlled, phase 2 trial, patients aged 18-60 years with 4 to 14 migraine days per month were enrolled at 59 headache and clinical research centres in North America and Europe, and randomly assigned in a 3:2:2:2 ratio to monthly subcutaneous placebo, AMG 334 7 mg, AMG 334 21 mg, or AMG 334 70 mg using a sponsor-generated randomisation sequence centrally executed by an interactive voice response or interactive web response system. Study site personnel, patients, and the sponsor study personnel were masked to the treatment assignment. The primary endpoint was the change in monthly migraine days from baseline to the last 4 weeks of the 12-week double-blind treatment phase. The primary endpoint was calculated using the least squares mean at each timepoint from a generalised linear mixed-effect model for repeated measures. Safety endpoints were adverse events, clinical laboratory values, vital signs, and anti-AMG 334 antibodies. The study is registered with ClinicalTrials.gov, number NCT01952574. An open-label extension phase of up to 256 weeks is ongoing and will assess the long-term safety of AMG 334.

FINDINGS

From Aug 6, 2013, to June 30, 2014, 483 patients were randomly assigned to placebo (n=160), AMG 334 7 mg (n=108), AMG 334 21 mg (n=108), or AMG 334 70 mg (n=107). The mean change in monthly migraine days at week 12 was -3·4 (SE 0·4) days with AMG 334 70 mg versus -2·3 (0·3) days with placebo (difference -1·1 days [95% CI -2·1 to -0·2], p=0·021). The mean reductions in monthly migraine days with the 7 mg (-2·2 [SE 0·4]) and the 21 mg (-2·4 [0·4]) doses were not significantly different from that with placebo. Adverse events were recorded in 82 (54%) patients who received placebo, 54 (50%) patients in the AMG 334 7 mg group, 54 (51%) patients in the AMG 334 21 mg group, and 57 (54%) patients in the AMG 334 70 mg group. The most frequently reported adverse events were nasopharyngitis, fatigue, and headache. Serious adverse events were reported for one patient in the AMG 334 7 mg group (ruptured ovarian cyst) and one patient in the AMG 334 70 mg group (migraine and vertigo); these events were judged to be unrelated to AMG 334 treatment. Nine (3%) of 317 patients had neutralising antibodies. No apparent association was recorded between patients with positive anti-AMG 334 antibodies and adverse events. No clinically significant vital signs, laboratory, or electrocardiogram findings were recorded.

INTERPRETATION

These results suggest that AMG 334 70 mg might be a potential therapy for migraine prevention in patients with episodic migraine and support further investigation of AMG 334 in larger phase 3 trials.

FUNDING

Amgen.

TEV-48125: a review of a monoclonal CGRP antibody in development for the preventive treatment of migraine

Calcitonin gene-related peptide (CGRP) is a 37-amino-acid neuropeptide whose involvement in migraine pathophysiology is well established. Originally migraine was believed to be a disease of the vasculature, but research has highlighted this to be a disease of the brain with CGRP playing an important role. While targeting CGRP using small molecule antagonists against the receptor has been effective, long-term use of these agents has not been possible due to safety concerns and/or formulation challenges. Recent advances in therapeutic antibodies have opened up new possibilities for treatment of migraine. TEV-48125 is one of four monoclonal antibodies targeting CGRP or its receptors, currently in development for the preventive treatment of migraine. This article discusses the in vitro and in vivo pharmacology of TEV-48125 as well as highlighting its safety profile through the six Phase 1 studies that have been conducted. Finally, the current state of development and future studies for TEV-48125 will be reviewed.

Calcitonin gene-related peptide: physiology and pathophysiology

Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide. Discovered 30 years ago, it is produced as a consequence of alternative RNA processing of the calcitonin gene. CGRP has two major forms (α and β). It belongs to a group of peptides that all act on an unusual receptor family. These receptors consist of calcitonin receptor-like receptor (CLR) linked to an essential receptor activity modifying protein (RAMP) that is necessary for full functionality. CGRP is a highly potent vasodilator and, partly as a consequence, possesses protective mechanisms that are important for physiological and pathological conditions involving the cardiovascular system and wound healing. CGRP is primarily released from sensory nerves and thus is implicated in pain pathways. The proven ability of CGRP antagonists to alleviate migraine has been of most interest in terms of drug development, and knowledge to date concerning this potential therapeutic area is discussed. Other areas covered, where there is less information known on CGRP, include arthritis, skin conditions, diabetes, and obesity. It is concluded that CGRP is an important peptide in mammalian biology, but it is too early at present to know if new medicines for disease treatment will emerge from our knowledge concerning this molecule.

Evaluation of cardiovascular parameters in cynomolgus monkeys following IV administration of LBR-101, a monoclonal antibody against calcitonin gene-related peptide

Calcitonin gene-related peptide (CGRP) is a well-validated target for migraine therapy and a known potent systemic vasodilator. LBR-101 is a monoclonal antibody against CGRP in clinical development for the preventive treatment of episodic and chronic migraine. Understanding the hemodynamic and cardiovascular consequences of chronic CGRP inhibition is therefore warranted. Given the conservation in CGRP sequence between monkeys and humans, addressing this question in monkeys is ideal as it allows dosing at super-therapeutic levels. To this end, two independent studies were conducted in monkeys: a single dedicated cardiovascular safety study and a repeat-dose, chronic study, both with electrocardiogram and hemodynamic assessments. LBR-101 was very well tolerated in both studies, with no clinically significant changes noted in any hemodynamic parameter, nor any relevant changes noted in any ECG parameter. In cynomolgus monkeys, cardiovascular and hemodynamic parameters do not appear to be affected by long-term inhibition of CGRP with LBR-101.

Cardiovascular and hemodynamic parameters in women following prolonged CGRP inhibition using LBR-101, a monoclonal antibody against CGRP

BACKGROUND

The vascular effects of acute calcitonin gene-related peptide (CGRP) inhibition are well described, but the effects of sustained inhibition warrant further exploration in humans.

OBJECTIVES

The objective of this article is to assess the effects of sustained CGRP inhibition on blood pressure, heart rate, and ECGs in healthy women ≥ 40 years of age.

METHODS

In this double-blind, placebo-controlled study, 31 women (mean age = 56) were randomized to receive placebo or an anti-CGRP monoclonal antibody at doses up to 2000 mg. Participants were confined for seven days and followed for 168 days. Cardiac telemetry was conducted for eight hours after infusion completion. Hemodynamic assessments and ECGs were conducted six times during Day 1 and periodically for three months.

RESULTS

No clinically relevant changes in systolic or diastolic blood pressure, heart rate, or ECG parameters (RR, PR, QRS, or QTcF) were observed when comparing baseline vs. post-dose time-points or in-between groups. No significant changes were seen for adjusted QTcF (baseline subtracted and placebo and baseline subtracted). No significant differences or relevant abnormalities were seen when comparing parameters obtained at Tmax vs. any other time-point.

CONCLUSION

Sustained CGRP inhibition was not associated with hemodynamic or ECG changes in a population at an increased age risk for cardiovascular events.

Calcitonin gene-related peptide and migraine with aura: A systematic review

Background

Calcitonin gene-related peptide (CGRP) is a key molecule in migraine pathophysiology. Most studies have focused on CGRP in relation to migraine without aura (MO). About one-third of migraine patients have attacks with aura (MA), and this is a systematic review of the current literature on CGRP and MA.

Methods

We performed a systematic literature search on MEDLINE for reports of CGRP and MA, covering basic science, animal and human studies as well as randomized clinical trials.

Results

The literature search identified 594 citations, of which 38 contained relevant, original data. Plasma levels of CGRP in MA patients are comparable to MO, but CGRP levels varied among studies. A number of animal studies, including knock-ins of familial hemiplegic migraine (FHM) genes, have examined the relationship between CGRP and cortical spreading depression. In patients, CGRP does not trigger migraine in FHM, but is a robust trigger of migraine-like headache both in MA and MO patients. The treatment effect of CGRP antagonists are well proven in the treatment of migraine, but no studies have studied the effect specifically in MA patients.

Conclusion

This systematic review indicates that the role of CGRP in MA is less studied than in MO. Further studies of the importance of CGRP for auras and migraine are needed.

BMS-927711 for the acute treatment of migraine: a double-blind, randomized, placebo controlled, dose-ranging trial

BACKGROUND

BMS-927711 is a potent, selective, competitive human calcitonin gene-related peptide (CGRP) receptor antagonist that has shown in vivo efficacy without vasoconstrictor effect. The objective of the current study was to determine an effective and tolerable dose range of BMS-927711 for the acute treatment of migraine.

METHODS

In this randomized, double-blind, placebo controlled, dose-ranging study, 885 patients were randomized using an adaptive design to one of the following dose groups: BMS-927711 (10, 25, 75, 150, 300, or 600 mg); sumatriptan 100 mg (active comparator); and placebo. Patients were treated for a single migraine attack. The primary endpoint was pain freedom at two hours post-dose.

RESULTS

Of patients who took the study drug, 799 had one post-randomization efficacy evaluation. Significantly more patients in the BMS-927711 75 mg (31.4%, P = 0.002), 150 mg (32.9%, P < 0.001), and 300 mg (29.7%, P = 0.002) groups and the sumatriptan group (35%, P < 0.001) had pain freedom at two hours post-dose versus placebo (15.3%). For the secondary endpoint of sustained pain freedom from two to 24 hours post-dose, BMS-927711 doses (25-600 mg) were also statistically significant compared with placebo. No deaths or treatment-related serious adverse events (AEs) were reported, and no patients discontinued because of AEs.

CONCLUSIONS

BMS-927711 is superior to placebo at several different doses (75 mg, 150 mg, and 300 mg) and has an excellent tolerability profile.

What's new in the migraine attack treatment

This short review aims to give a focus on news in the migraine attack treatment and discusses the CGRP receptor antagonists (gepants), the 5-HT1F receptors agonists (ditans), the transcranial magnetic stimulation for the treatment of migraine attack with aura, innovative delivery systems for sumatriptan and the oral inhalation of dihydroergotamine.