Safety, tolerability, and efficacy of TEV-48125 for preventive treatment of chronic migraine: a multicentre, randomised, double-blind, placebo-controlled, phase 2b study

The evolving landscape and research trend of calcitonin gene-related peptide in migraine: A bibliometric analysis and visualization

Background

Migraine is a global public health concern, affecting both social and individual well-being. Calcitonin gene-related peptide (CGRP), a crucial neuropeptide, holds important research value in understanding migraine pathogenesis. CGRP receptor antagonists and monoclonal antibodies that target CGRP or its receptors have shown efficacy in reducing migraine frequency and severity, presenting a promising therapeutic approach. This study aimed to conduct a comprehensive bibliometric analysis to analyze the current state, research trends, and future directions of CGRP in migraine.

Methods

Bibliometric tools including CiteSpace, VOSviewer, etc., were utilized to extract and summarize publications related to CGRP in migraine from the Web of Science Core Collection Database (WOSCC) between 2004 and 2023, as of December 31, 2023. The analysis focused on trends in annual publications, leading countries/regions and institutions, prominent journals and references, influential authors, and high-frequency keywords in the field.

Results

A total of 1,821 articles and reviews involving 5,180 authors from 1,315 organizations across 64 countries were included in the study. These publications were distributed across 362 journals and accumulated 56,999 citations by December 31, 2023. An increasing trend was observed in annual publications on CGRP in migraine. The United States emerged as the leading nation in both publications and citations, with academic Peter Goadsby contributing the highest number of publications. The University of Copenhagen stood out as the institution with the most publications, and Cephalalgia emerged as the most influential journal. The most cited paper identified was "Calcitonin gene-related peptide receptor antagonist BIBN4096BS for the acute treatment of migraine" by Jes Olesen, published in the New Engl Med. Keyword frequency analysis revealed prevalent terms such as "migraine," "CGRP," and "episodic migraine," along with emerging topics represented by keywords including "trial," "monoclonal antibodies," "preventive treatment," and "safety."

Conclusion

CGRP is pivotal in migraine pathogenesis, and there is a robust research foundation exploring its role. The US leads in research output on CGRP in migraine. Investigating the mechanism of CGRP and its receptor in migraine remains a key area of interest, particularly focusing on signaling pathways. Future research should target identifying critical therapeutic targets in CGRP antagonist pathways for migraine treatment.

Revolutionizing migraine management: advances and challenges in CGRP-targeted therapies and their clinical implications

Migraine, a prevalent neurological disorder, affects approximately 14.1% of the global population and disproportionately impacts females. This debilitating condition significantly compromises quality of life, productivity, and incurs high healthcare costs, presenting a challenge not only to individuals but to societal structures as a whole. Despite advances in our understanding of migraine pathophysiology, treatment options remain limited, necessitating ongoing research into effective therapies. This review delves into the complexity of migraine management, examining the roles of genetic predisposition, environmental influences, personalized treatment approaches, comorbidities, efficacy and safety of existing acute and preventive treatments. It further explores the continuum between migraine and tension-type headaches and discusses the intricacies of treating various migraine subtypes, including those with and without aura. We emphasize the recent paradigm shift toward trigeminovascular activation and the release of vasoactive substances, such as calcitonin gene-related peptide (CGRP), which offer novel therapeutic targets. We assess groundbreaking clinical trials, pharmacokinetic and pharmacodynamic perspectives, safety, tolerability, and the real-world application of CGRP monoclonal antibodies and gepants. In the face of persisting treatment barriers such as misdiagnosis, medication overuse headaches, and limited access to specialist care, we discuss innovative CGRP-targeted strategies, the high cost and scarcity of long-term efficacy data, and suggest comprehensive solutions tailored to Turkiye and developing countries. The review offers strategic recommendations including the formulation of primary care guidelines, establishment of specialized outpatient clinics, updating physicians on novel treatments, enhancing global accessibility to advanced therapies, and fostering patient education. Emphasizing the importance of lifestyle modifications and holistic approaches, the review underscores the potential of mass media and patient groups in disseminating critical health information and shaping the future of migraine management.

Treatment Outcome After Switching From Galcanezumab to Fremanezumab in Patients With Migraine

BACKGROUND AND PURPOSE

Monoclonal antibodies (mAbs) targeting calcitonin-gene-related peptide (CGRP) or its receptor (anti-CGRP-R) have been widely administered to patients with migraine who show inadequate responses to preventive medications. Among patients in whom a particular anti-CGRP-R mAb is ineffective, switching between different anti-CGRP-R mAbs can be the next option. Few studies have investigated treatment outcomes for antibody switching, especially between mAbs with the same target of the CGRP ligand. We aimed to determine the treatment outcome after switching between two anti-CGRP mAbs (galcanezumab to fremanezumab).

METHODS

We identified migraine patients in a prospective headache clinic registry who received galcanezumab for ≥3 months and were switched to fremanezumab for a further ≥3 months at a single university hospital. We defined a treatment response as a ≥50% reduction in the number of days with a moderate or severe headache at the third month of treatment relative to baseline. The treatment response after switching to fremanezumab was compared with the initial treatment response to galcanezumab.

RESULTS

Among 21 patients identified in the registry, 7 (33.3%) were initial responders to galcanezumab. After switching to fremanezumab, 7 (33.3%) showed a treatment response. The treatment response rate was 28.6% in the initial responders and 71.4% in the nonresponders to galcanezumab (p>0.999).

CONCLUSIONS

Switching between anti-CGRP mAbs (galcanezumab to fremanezumab) yielded a treatment outcome comparable to that reported previously when switching from an anti-CGRP-R mAb (erenumab) to an anti-CGRP mAb (galcanezumab or fremanezumab). The treatment response to fremanezumab seems to be independent of the prior treatment response to galcanezumab. Our findings suggest that switching to another anti-CGRP mAb can be considered when a particular anti-CGRP mAb is ineffective or intolerable.

Reporting Quality and Risk of Bias Analysis of Published RCTs Assessing Anti-CGRP Monoclonal Antibodies in Migraine Prophylaxis: A Systematic Review

Objective: Phase II/III randomized clinical trials (RCTs) are vulnerable to many types of bias beyond randomization. Insights into the reporting quality of RCTs involving migraine patients treated with monoclonal antibodies targeting the calcitonin gene-related peptide system (anti-CGRP MAbs) are currently lacking. Our aim was to analyze the reporting quality of phase II/III RCTs involving migraine patients treated with anti-CGRP MAbs. Methods: A systematic search was performed on the PubMed and EMBASE databases, according to PRISMA guidelines, for relevant RCTs in either episodic or chronic migraine prevention. Additionally, an adapted version of the 2010 CONSORT statement checklist was utilized. The ROBvis online tool was used to document the risk of bias. Results: From the initially identified 179 articles, we finally found 31 RCTs that were eligible for evaluation. The average CONSORT compliance was 88.7% (69.7-100%), while 93.5% (N = 29) of the articles had a compliance greater than 75%. Twenty-eight CONSORT items were reported in more than 75% of the articles. The average compliance of the analyzed RCTs was 93.9% for Galcanezumab, 91.3% for Fremanezumab, followed by 85.4% for Erenumab and Eptinezumab studies. Implementation of the ROB2 tool showed some concerning "missing information" arising from the inadequate reporting. Specifically, 50% of the studies (N = 16) were categorized as having inadequate information regarding the randomization process. Conclusions: Adequate reporting quality was disclosed in the evaluated RCTs with anti-CGRP MAbs in migraine prevention. However, some methodological issues need to be highlighted to be addressed in future studies assessing the efficacy of new molecules targeting CGRP or other candidate pathways implicated in migraine pathophysiology.

Drug-related side effects and adverse reactions in the treatment of migraine: a bibliometric and visual analysis

Background

Migraine imposes a substantial global burden, impacting patients and society. Pharmacotherapy, as a primary treatment, entails specific adverse reactions. Emphasizing these reactions is pivotal for improving treatment strategies and enhancing patients' well-being. Thus, we conducted a comprehensive bibliometric and visual analysis of relevant literature.

Methodology

We conducted a comprehensive search on the Science Citation Index Expanded within the Web of Science, restricting the literature for analysis based on criteria such as document type, publication date, and language. Subsequently, we utilized various analytical tools, including VOSviewer, Scimago Graphica, the R package 'bibliometrix', CiteSpace, and Excel programs, for a meticulous examination and systematic organization of data concerning journals, authors, countries/regions, institutions, keywords, and references.

Results

By August 31, 2023, the literature was distributed across 379 journals worldwide, authored by 4,235 individuals from 1726 institutions. It featured 2,363 keywords and 38,412 references. 'HEADACHE' led in publication count, with 'SILBERSTEIN S' as the most prolific author. The United States ranked highest in publication volume, with 'UNIV COPENHAGEN' leading among institutions.

Conclusion

Our research findings indicate that researchers in the field continue to maintain a focus on the calcitonin gene-related peptide (CGRP) system and explore diverse mechanisms for drug development through the application of novel biotechnological approaches. Furthermore, it is imperative to enhance the assessment of clinical trial outcomes, consistently monitor the efficacy and safety of prominent drugs such as Erenumab and Fremanezumab. There is a need for further evaluation of acute and preventive treatments tailored to different populations and varying types of migraine.

Drug-related side effects and adverse reactions in the treatment of migraine: a bibliometric and visual analysis

BACKGROUND

Migraine imposes a substantial global burden, impacting patients and society. Pharmacotherapy, as a primary treatment, entails specific adverse reactions. Emphasizing these reactions is pivotal for improving treatment strategies and enhancing patients' well-being. Thus, we conducted a comprehensive bibliometric and visual analysis of relevant literature.

METHODOLOGY

We conducted a comprehensive search on the Science Citation Index Expanded within the Web of Science, restricting the literature for analysis based on criteria such as document type, publication date, and language. Subsequently, we utilized various analytical tools, including VOSviewer, Scimago Graphica, the R package 'bibliometrix', CiteSpace, and Excel programs, for a meticulous examination and systematic organization of data concerning journals, authors, countries/regions, institutions, keywords, and references.

RESULTS

By August 31, 2023, the literature was distributed across 379 journals worldwide, authored by 4,235 individuals from 1726 institutions. It featured 2,363 keywords and 38,412 references. 'HEADACHE' led in publication count, with 'SILBERSTEIN S' as the most prolific author. The United States ranked highest in publication volume, with 'UNIV COPENHAGEN' leading among institutions.

CONCLUSION

Our research findings indicate that researchers in the field continue to maintain a focus on the calcitonin gene-related peptide (CGRP) system and explore diverse mechanisms for drug development through the application of novel biotechnological approaches. Furthermore, it is imperative to enhance the assessment of clinical trial outcomes, consistently monitor the efficacy and safety of prominent drugs such as Erenumab and Fremanezumab. There is a need for further evaluation of acute and preventive treatments tailored to different populations and varying types of migraine.

Real-world effectiveness of Anti-CGRP monoclonal antibodies compared to OnabotulinumtoxinA (RAMO) in chronic migraine: a retrospective, observational, multicenter, cohort study

BACKGROUND

Chronic migraine (CM) is a disabling condition with high prevalence in the general population. Until the recent approval of monoclonal antibodies targeting the calcitonin gene-related peptide (Anti-CGRP mAbs), OnabotulinumtoxinA (BoNT-A) was the only treatment specifically approved for CM prophylaxis. Direct comparisons between the two treatments are not available so far.

METHODS

We performed an observational, retrospective, multicenter study in Italy to compare the real-world effectiveness of Anti-CGRP mAbs and BoNT-A. Patients with CM who had received either treatment according to Italian prescribing regulations were extracted from available clinical databases. Efficacy outcomes included the change from baseline in monthly headache days (MHD), MIgraine Disability ASsessment test (MIDAS), and monthly acute medications (MAM) evaluated at 6 and 12 months of follow-up. The primary outcome was MHD change from baseline at 12 months. Safety outcomes included serious adverse events (SAE) and treatment discontinuation. Unadjusted and adjusted models were used for the analyses.

RESULTS

Two hundred sixteen potentially eligible patients were screened; 183 (86 Anti-CGRP mAbs; 97 BoNT-A) were included. One hundred seventy-one (80 Anti-CGRP mAbs; 91 BoNT-A) and 154 (69 Anti-CGRP mAbs; 85 BoNT-A) patients were included in the efficacy analysis at 6 and 12 months of follow-up, respectively. Anti-CGRP mAbs and BoNT-A both resulted in a mean MHD reduction at 6 (-11.5 and -7.2 days, respectively; unadjusted mean difference -4.3; 95%CI -6.6 to -2.0; p = 0.0003) and 12 months (-11.9 and -7.6, respectively; unadjusted mean difference -4.4; 95%CI -6.8 to -2.0; p = 0.0002) of follow-up. Similar results were observed after adjusting for baseline confounders. Anti-CGRP mAbs showed a significant MIDAS (-31.7 and -19.2 points, p = 0.0001 and p = 0.0296, respectively) and MAM reduction (-5.1 and -3.1 administrations, p = 0.0023 and p = 0.0574, respectively) compared to BoNT-A at 6 and 12 months. No SAEs were reported. One patient receiving fremanezumab discontinued treatment due to arthralgia. Treatment discontinuations, mainly for inefficacy, were comparable.

CONCLUSION

Both Anti-CGRP mAbs and BoNT-A were effective in CM patients with Anti-CGRP mAbs presenting higher effect magnitude, with comparable safety. Still, BoNT-A remains a valuable option for CM patients with contraindications to Anti-CGRP mAbs or for frail categories who are candidates to local therapy with limited risk of systemic administration.

IUPHAR review: Navigating the role of preclinical models in pain research

Chronic pain is a complex and challenging medical condition that affects millions of people worldwide. Understanding the underlying mechanisms of chronic pain is a key goal of preclinical pain research so that more effective treatment strategies can be developed. In this review, we explore nociception, pain, and the multifaceted factors that lead to chronic pain by focusing on preclinical models. We provide a detailed look into inflammatory and neuropathic pain models and discuss the most used animal models for studying the mechanisms behind these conditions. Additionally, we emphasize the vital role of these preclinical models in developing new pain-relief drugs, focusing on biologics and the therapeutic potential of NMDA and cannabinoid receptor antagonists. We also discuss the challenges of TRPV1 modulation for pain treatment, the clinical failures of neurokinin (NK)- 1 receptor antagonists, and the partial success story of Ziconotide to provide valuable lessons for preclinical pain models. Finally, we highlight the overall success and limitations of current treatments for chronic pain while providing critical insights into the development of more effective therapies to alleviate the burden of chronic pain.

Characteristics associated with response to subcutaneously administered anti-CGRP monoclonal antibody medications in a real-world community cohort of persons living with migraine: A retrospective clinical and genetic study

OBJECTIVE

To evaluate response to anti-calcitonin gene-related peptide (CGRP) migraine preventives in a real-world community cohort of persons living with migraine and to identify clinical and genetic characteristics associated with efficacious response.

BACKGROUND

Erenumab-aooeb, fremanezumab-vrfm, and galcanezumab-gnlm target CGRP or its receptor; however, many patients are non-responsive.

METHODS

In this retrospective clinical and genetic study, we identified 1077 adult patients who satisfied the International Classification of Headache Disorders, 3rd edition, criteria for migraine without aura, migraine with aura, or chronic migraine and who were prescribed an anti-CGRP migraine preventive between May 2018 and May 2021. Screening of 558 patients identified 289 with data at baseline and first follow-up visits; data were available for 161 patients at a second follow-up visit. The primary outcome was migraine days per month (MDM). In 198 genotyped patients, we evaluated associations between responders (i.e., patients with ≥50% reduction in MDM at follow-up) and genes involved in CGRP signaling or pharmacological response, and genetic and polygenic risk scores.

RESULTS

The median time to first follow-up was 4.4 (0.9-22) months after preventive start. At the second follow-up, 5.7 (0.9-13) months later, 145 patients had continued on the same preventive. Preventives had strong, persistent effects in reducing MDM in responders (follow-up 1: η2  = 0.26, follow-up 2: η2  = 0.22). At the first but not second follow-up: galcanezumab had a larger effect than erenumab, while no difference was seen at either follow-up between galcanezumab and fremanezumab or fremanezumab and erenumab. The decrease in MDM at follow-up was generally proportional to baseline MDM, larger in females, and increased with months on medication. At the first follow-up only, patients with prior hospitalization for migraine or who had not responded to more preventive regimens had a smaller decrease in MDM. Reasons for stopping or switching a preventive varied between medications and were often related to cost and insurance coverage. At both follow-ups, patient tolerance (1: 92.2% [262/284]; 2: 95.2% [141/145]) and continued use (1: 77.5% [224/289]; 2: 80.6% [116/145]) were high and similar across preventives. Response consistency (always non-responders: 31.7% [46/145]; always responders: 56.5% [82/145], and one-time only responders: 11.7% [17/145]) was also similar across preventives. Non-responder status had nominally significant associations with rs12615320-G in RAMP1 (odds ratio [95% confidence interval]: 4.7 [1.5, 14.7]), and rs4680-A in COMT (0.6[0.4, 0.9]). Non-responders had a lower mean genetic risk score than responders (1.0 vs. 1.1; t(df) = -1.75(174.84), p = 0.041), and the fraction of responders increased with genetic and polygenic risk score percentile.

CONCLUSIONS

In this real-world setting, anti-CGRP preventives reduced MDM persistently and had similar and large effect sizes on MDM reduction; however, clinical and genetic factors influenced response.

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.

Real-world effectiveness of fremanezumab for the preventive treatment of migraine: Interim analysis of the pan-European, prospective, observational, phase 4 PEARL study

BACKGROUND

The ongoing Pan-European Real Life (PEARL) phase 4 study is evaluating fremanezumab effectiveness and safety for the prevention of episodic and chronic migraine. This interim analysis reports primary, secondary and exploratory endpoints from when 500 participants completed at least six months of treatment.

METHODS

Adults with episodic migraine or chronic migraine maintaining daily headache diaries were enrolled upon initiation of fremanezumab. Primary endpoint: proportion of participants with ≥50% reduction in monthly migraine days during the six-month period after fremanezumab initiation. Secondary endpoints: mean change from baseline across months 1-12 in monthly migraine days, acute migraine medication use, and headache-related disability. Exploratory endpoint: mean change in headache severity from baseline across months 1-12. Safety was assessed through adverse events reported.

RESULTS

Overall, 897 participants were enrolled and 574 included in the effectiveness analyses (episodic migraine, 25.8%; chronic migraine, 74.2%). Of participants with data available, 175/313 (55.9%) achieved ≥50% monthly migraine days reduction during the six-month period post-initiation. Across months 1-12, there were sustained reductions in mean monthly migraine days, acute medication use, disability scores, and headache severity. Few adverse events were reported.

CONCLUSION

PEARL interim results support the effectiveness and safety of fremanezumab for migraine prevention in a real-world population across several European countries.Trial registration: encepp.eu: EUPAS35111.

Atogepant for the preventive treatment of chronic migraine (PROGRESS): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

In this study, we aimed to evaluate the efficacy, safety, and tolerability of atogepant for the preventive treatment of chronic migraine.

METHODS

We did this randomised, double-blind, placebo-controlled, phase 3 trial at 142 clinical research sites across the USA, the UK, Canada, China, Czech Republic, Denmark, France, Germany, Italy, Japan, South Korea, Poland, Russia, Spain, Sweden, and Taiwan. Adults aged 18-80 years with a 1-year or longer history of chronic migraine were randomly assigned (1:1:1) to receive oral atogepant 30 mg twice a day, oral atogepant 60 mg once a day, or placebo. The primary endpoint was change from baseline in mean monthly migraine days (MMDs) across the 12-week treatment period. The primary analysis was done in the modified intent-to-treat population and included all randomly assigned participants who received at least one dose of study intervention, had an evaluable baseline period of electronic diary (eDiary) data, and had at least one evaluable post-baseline 4-week period (weeks 1-4, 5-8, and 9-12) of eDiary data during the double-blind period. The safety population consisted of all participants who received at least one dose of study intervention. This trial is registered with ClinicalTrials.gov (NCT03855137).

FINDINGS

Between March 11, 2019 and Jan 20, 2022, 1489 participants were assessed for eligibility. 711 were excluded, and 778 participants were randomly assigned to atogepant 30 mg twice a day (n=257), atogepant 60 mg once a day (n=262), or placebo (n=259). Participants in the safety population were aged 18-74 years (mean 42·1 years). 459 (59%) of 773 patients were White, 677 (88%) patients were female, and 96 (12%) were male. 84 participants discontinued treatment during the trial, and 755 comprised the modified intent-to-treat population (atogepant 30 mg twice a day n=253, atogepant 60 mg once a day n=256, and placebo n=246). Baseline mean number of MMDs were 18·6 (SE 5·1) with atogepant 30 mg twice a day, 19·2 (5·3) with atogepant 60 mg once a day, and 18·9 (4·8) with placebo. Change from baseline in mean MMDs across 12 weeks was -7·5 (SE 0·4) with atogepant 30 mg twice a day, -6·9 (0·4) with atogepant 60 mg once a day, and -5·1 (0·4) with placebo. Least squares mean difference from placebo was -2·4 with atogepant 30 mg twice a day (95% CI -3·5 to -1·3; adjusted p<0·0001) and -1·8 with atogepant 60 mg once a day (-2·9 to -0·8; adjusted p=0·0009). Most common adverse events for atogepant were constipation (30 mg twice a day 28 [10·9%]; 60 mg once a day 26 [10%]; and placebo 8 [3%]) and nausea (30 mg twice a day 20 [8%]; 60 mg once a day 25 [10%]; and placebo 9 [4%]). Potentially clinically significant weight decrease (≥7% reduction at any time post-baseline) was observed in each treatment group (atogepant 30 mg twice a day 14 [6%]; atogepant 60 mg once a day 15 [6%]; and placebo 5 [2%]).

INTERPRETATION

Atogepant 30 mg twice a day and 60 mg once a day showed clinically relevant reductions in MMDs across 12 weeks in chronic migraine patients. Both atogepant doses were well tolerated, consistent with the known safety profile of atogepant.

FUNDING

Allergan (now AbbVie).

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.

Molecular Mechanisms of Migraine: Nitric Oxide Synthase and Neuropeptides

Migraine is a common condition with disabling attacks that burdens people in the prime of their working lives. Despite years of research into migraine pathophysiology and therapeutics, much remains to be learned about the mechanisms at play in this complex neurovascular condition. Additionally, there remains a relative paucity of specific and targeted therapies available. Many sufferers remain underserved by currently available broad action preventive strategies, which are also complicated by poor tolerance and adverse effects. The development of preclinical migraine models in the laboratory, and the advances in human experimental migraine provocation, have led to the identification of key molecules likely involved in the molecular circuity of migraine, and have provided novel therapeutic targets. Importantly, the identification that vasoconstriction is neither necessary nor required for headache abortion has changed the landscape of migraine treatment and has broadened the therapy targets for patients with vascular risk factors or vascular disease. These targets include nitric oxide synthase (NOS) and several neuropeptides that are involved in migraine. The ability of NO donors and infusion of some of these peptides into humans to trigger typical migraine-like attacks has supported the development of targeted therapies against these molecules. Some of these, such as those targeting calcitonin gene-related peptide (CGRP), have already reached clinical practice and are displaying a positive outcome in migraineurs for the better by offering targeted efficacy without significant adverse effects. Others, such as those targeting pituitary adenylate cyclase activating polypeptide (PACAP), are showing promise and are likely to enter phase 3 clinical trials in the near future. Understanding these nitrergic and peptidergic mechanisms in migraine and their interactions is likely to lead to further therapeutic strategies for migraine in the future.

The ATP sensitive potassium channel (KATP) is a novel target for migraine drug development

Migraine is one of the leading causes of disability worldwide, affecting work and social life. It has been estimated that sales of migraine medicines will reach 12.9 billion USD in 2027. To reduce social impact, migraine treatments must improve, and the ATP-sensitive potassium (K_ATP) channel is a promising target because of the growing evidence of its implications in the pathogenesis of migraine. Strong human data show that opening of the K_ATP channel using levcromakalim is the most potent headache and migraine trigger ever tested as it induces headache in almost all healthy subjects and migraine attacks in 100% of migraine sufferers. This review will address the basics of the K_ATP channel together with clinical and preclinical data on migraine implications. We argue that K_ATP channel blocking, especially the Kir6.1/SUR2B subtype, may be a target for migraine drug development, however translational issues remain. There are no human data on the closure of the K_ATP channel, although blocking the channel is effective in animal models of migraine. We believe there is a good likelihood that an antagonist of the Kir6.1/SUR2B subtype of the K_ATP channel will be effective in the treatment of migraine. The side effects of such a blocker may be an issue for clinical use, but the risk is likely only moderate. Future clinical trials of a selective Kir6.1/SUR2B blocker will answer these questions.

Methodological considerations on real-world evidence studies of monoclonal antibodies against the CGRP-pathway for migraine: a systematic review

BACKGROUND

Real-world data are accumulating on the effectiveness, tolerability and safety of anti-calcitonin gene-related peptide pathway monoclonal antibodies for the preventive treatment of migraine. We performed a systematic review of the methodology of prospective, observational, clinic-based real-world evidence studies with these drugs in both episodic and chronic migraine.

METHODS

The objectives were to evaluate the definitions and reported outcomes used, and to perform a risk of bias assessment for each of the different studies. PubMed and EMBASE were systematically queried for relevant scientific articles. Study quality assessment of the included studies was conducted using the "National Heart, Lung and Blood Institute (NHLBI) Study Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group".

RESULTS

Forty-six studies fitted the criteria for the systematic review and were included in the analysis. Ten studies (21.7%) defined a migraine day for the study, while only 5 studies defined a headache day for the study (10.9%). The most common primary endpoint/objective of the studies was change in monthly migraine days (n = 16, 34.8%), followed by responder rate (n = 15, 32.6%) and change in monthly headache days (n = 5, 10.9%). Eight studies (17.4%) did not define the primary endpoint/objective. Thirty-three studies were graded as "good" quality and 13 studies were graded as "fair".

CONCLUSION

Our analysis shows rather significant heterogeneity and/or lack of predefined primary outcomes/objectives, definitions of outcomes measures and the use of longitudinal monitoring (e.g. headache diaries). Standardization of terminology, definitions and protocol procedures for real-world evidence studies of preventive treatments for migraine are recommended.

TRIAL REGISTRATION

This study was registered with PROSPERO with ID CRD42022369366.

The temporal trend of placebo response in migraine prevention from 1990 to 2021: a systematic literature review and meta-analysis with regression

BACKGROUND

Migraine affects 1.1 billion people globally and is the second leading cause of disability worldwide. In clinical trials, treatment efficacy is evaluated by comparing the differential responses in the treatment and placebo arms. Although placebo response in preventive migraine trials has been studied, there is limited research examining temporal trends. This study evaluates the trend of placebo response over thirty years in migraine prevention trials and investigates the association of potential confounders, such as patient, treatment, and study characteristics on placebo response using meta-analysis with regression.

METHODS

We conducted literature searches from January 1990 to August 2021 in bibliographical databases (PubMed, Cochrane Library, and EMBASE). Studies were selected according to PICOS criteria and included randomized, double-blind, placebo-controlled trials evaluating preventive migraine treatments in adult patients diagnosed with episodic or chronic migraine, with or without aura. The protocol was registered with PROSPERO (CRD42021271732). Migraine efficacy outcomes included were either continuous (e.g., monthly migraine days) or dichotomous (e.g., ≥ 50% responder rate (yes/no)). We assessed the correlation of the change in outcome from baseline in the placebo arm, with the year of publication. The relationship between placebo response and year of publication was also assessed after accounting to confounders.

RESULTS

A total of 907 studies were identified, and 83 were found eligible. For the continuous outcomes, the change from baseline in mean placebo response showed an increase over the years (rho = 0.32, p = 0.006). The multivariable regression analysis also showed an overall increase in placebo response over the years. The correlation analysis of dichotomous responses showed no significant linear trend between publication year and mean placebo response (rho = 0.08, p = 0.596). Placebo response also varied by route of administration.

CONCLUSION

Placebo response increased over the past 30 years in migraine preventive trials. This phenomenon should be considered when designing clinical trials and conducting meta-analyses.

Emerging drugs for the preventive treatment of migraine: a review of CGRP monoclonal antibodies and gepants trials

INTRODUCTION

Migraine is a leading cause of years lived with disability and preventive strategies represent a mainstay to reduce health-related disability and improve quality of life of migraine patients. Until a few years ago, migraine prevention was based on drugs developed for other clinical indications and relocated in the migraine therapeutic armamentarium, characterized by unfavourable tolerability profiles. The advent of monoclonal antibodies against Calcitonin Gene-Related Peptide (CGRP) and gepants, CGRP receptor antagonists, has been a turning point in migraine prevention owing to advantageous efficacy, safety and tolerability profiles.Nevertheless, while in an ideal scenario a drug characterized by significant greater efficacy and tolerability compared to existing therapeutic strategies should be adopted as a first-line treatment, cost-effectiveness analyses available for monoclonal antibodies against CGRP pathway tend to limit their administration to more severe migraine phenotypes.

AREAS COVERED

The present narrative review aim to provide a critical appraisal of phase II and III CGRP-mAbs and gepants trials to analyse their use in clinical practice.

EXPERT OPINION

Despite monoclonal antibodies against CGRP pathway and gepants can be undoubtedly considered top-of-the-range treatments, there are still issues deserving to be addressed in the coming years as the risk of off-target effects as well as their economic sustainability based on the considerable migraine burden.

Shared and independent roles of CGRP and PACAP in migraine pathophysiology

The neuropeptides calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) have emerged as mediators of migraine pathogenesis. Both are vasodilatory peptides that can cause migraine-like attacks when infused into people and migraine-like symptoms when injected into rodents. In this narrative review, we compare the similarities and differences between the peptides in both their clinical and preclinical migraine actions. A notable clinical difference is that PACAP, but not CGRP, causes premonitory-like symptoms in patients. Both peptides are found in distinct, but overlapping areas relevant to migraine, most notably with the prevalence of CGRP in trigeminal ganglia and PACAP in sphenopalatine ganglia. In rodents, the two peptides share activities, including vasodilation, neurogenic inflammation, and nociception. Most strikingly, CGRP and PACAP cause similar migraine-like symptoms in rodents that are manifested as light aversion and tactile allodynia. Yet, the peptides appear to act by independent mechanisms possibly by distinct intracellular signaling pathways. The complexity of these signaling pathways is magnified by the existence of multiple CGRP and PACAP receptors that may contribute to migraine pathogenesis. Based on these differences, we suggest PACAP and its receptors provide a rich set of targets to complement and augment the current CGRP-based migraine therapeutics.

Determining the Efficacy and Safety of Acupuncture for the Preventive Treatment of Menstrual Migraine: A Protocol for a PRISMA-Compliant Systematic Review and Meta-Analysis

Background

Menstrual migraine (MM), as a common type of headache related to women's menstrual cycle, currently available treatments do not produce sufficient effectiveness, making it remains difficult to manage. Although acupuncture may be an effective treatment for MM, there is a lack of convincing evidence to recommend acupuncture to patients with MM until more solid evidence is produced. Therefore, the purpose of our systematic review (SR) and meta-analysis protocol is to synthesize up-to-date evidence regarding the clinical efficacy and safety of acupuncture on MM.

Methods

To find qualifying RCTs, nine databases will be searched. RevMan 5.3 will be used to combine the retrieved data for meta-analyses. The Cochrane risk of bias instrument will be used to assess the methodological quality of each included trial. The strength and certainty of the evidence will be evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Additionally, we will undertake sensitivity analyses, publication bias, and subgroup analyses if available.

Discussion

Our SR and meta-analysis protocol will contribute to determining acupuncture's therapeutic effect and safety in the preventive treatment of MM. Based on the up-to-date evidence produced by the subsequent SR and meta-analysis, informed treatment decisions will be made by patients, physicians and policy makers.

Role of PACAP in migraine: An alternative to CGRP?

Migraine is a widespread and debilitating neurological condition affecting more than a billion people worldwide. Thus, more effective migraine therapies are highly needed. In the last decade, two endogenous neuropeptides, calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating peptide (PACAP), were identified to be implicated in migraine. Recently, introduction of monoclonal antibodies (mAbs) blocking the CGRP is the most important advance in migraine therapy for decades. However, 40% of patients are unresponsive to these new drugs. We believe that PACAP may be involved in these patients. Like CGRP, PACAP is located to sensory nerve fibers, it dilates cranial arteries, it causes migraine when infused into patients and it is a peptide that lends itself to antibody therapy. Also, recent studies suggest that the PACAP pathway is independent of the CGRP pathway. Understanding the signaling pathways of PACAP may therefore lead to identification of novel therapeutic targets of particular interest in patients unresponsive to anti-CGRP therapy. Accordingly, neutralizing mAb to PACAP is currently in clinical phase II development. The aim of the present review is, therefore, to give a thorough account of the existing data on PACAP, its receptors and its relation to migraine.

Assessment of the relative effectiveness of erenumab compared with onabotulinumtoxinA for the prevention of chronic migraine

OBJECTIVE

To assess the available clinical and economic evidence of erenumab vs onabotulinumtoxinA for chronic migraine (CM) and present de-novo indirect treatment comparisons (ITCs) based on available clinical trial data.

METHODS

We conducted ITCs based on results from the pivotal 295 trial (NCT02066415) of erenumab vs placebo and published aggregate data from the PREEMPT 1 (NCT00156910) and PREEMPT 2 (NCT00168428) trials of onabotulinumtoxinA vs placebo. ITCs were conducted for CM patients with and without prior administration of onabotulinumtoxinA and among CM patients with ≥3 prior preventive treatment failures. Efficacy was assessed based on responder rates of ≥50% reductions in monthly headache days (MHDs) and monthly migraine days (MMDs) as well as change from baseline in both MHDs and MMDs.

RESULTS

Among patients with CM, 140 mg erenumab was associated with a reduction of 1.2 MHD (p = .092) and a reduction of 1.0 MMD (p = .174) compared to onabotulinumtoxinA at Week 12. Among onabotulinumtoxinA-naïve patients, erenumab was associated with a reduction of 1.8 MHD (p = .026) and 1.4 MMD (p = .080) at Week 12. Among patients that had received ≥3 prior preventive treatments, the odds ratios comparing erenumab vs onabotulinumtoxinA were 1.7 for ≥50% responder rates based on reductions in MHD (p = .155) and 1.7 for ≥50% responder rates based on reductions in MMD (p = .140).

CONCLUSION

These findings suggest directional benefits (although not reaching the threshold of statistical significance) associated with erenumab vs onabotulinumtoxinA for the preventive treatment of CM. Evidence from this study may inform healthcare stakeholders in treatment selection and optimization for patients with CM.

Review of Tolerability of Fremanezumab for Episodic and Chronic Migraine

Calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) were the first class of medication specifically developed for the prevention of migraine. Fremanezumab is one of four CGRP mAbs currently available and is approved by the US Food and Drug Administration (FDA) for the preventative treatment of episodic and chronic migraines. This narrative review summarizes the history of fremanezumab development, the trials that led to its approval, and the later studies published evaluating its tolerability and efficacy. Evidence of fremanezumab for clinically significant efficacy and tolerability in patients with chronic migraine is especially important when considering the high level of disability, lower quality of life scores, and higher levels of health-care utilization associated with this condition. Multiple clinical trials demonstrated superiority of fremanezumab over placebo in terms of efficacy while demonstrating good tolerability. Treatment-related adverse reactions did not differ significantly compared to placebo and dropout rates were minimal. The most commonly observed treatment-related adverse reaction was mild-to-moderate injection site reaction, described as erythema, pain, induration, or swelling at the injection site.

PACAP signaling is not involved in GTN- and levcromakalim-induced hypersensitivity in mouse models of migraine

BACKGROUND

Calcitonin gene-related peptide (CGRP) antagonizing drugs represents the most important advance in migraine therapy for decades. However, these new drugs are only effective in 50-60% of patients. Recent studies have shown that the pituitary adenylate cyclase-activating peptide (PACAP38) pathway is independent from the CGRP signaling pathway. Here, we investigate PACAP38 signaling pathways in relation to glyceryl trinitrate (GTN), levcromakalim and sumatriptan.

METHODS

In vivo mouse models of PACAP38-, GTN-, and levcromakalim-induced migraine were applied using tactile sensitivity to von Frey filaments as measuring readout. Signaling pathways involved in the three models were dissected using PACAP-inhibiting antibodies (mAbs) and sumatriptan.

RESULTS

We showed that PACAP mAbs block PACAP38 induced hypersensitivity, but not via signaling pathways involved in GTN and levcromakalim. Also, sumatriptan has no effect on PACAP38-induced hypersensitivity relevant to migraine. This is the first study testing the effect of a PACAP-inhibiting drug on GTN- and levcromakalim-induced hypersensitivity.

CONCLUSIONS

Based on the findings in our mouse model of migraine using migraine-inducing compounds and anti-migraine drugs, we suggest that PACAP acts via a distinct pathway. Using PACAP38 antagonism may be a novel therapeutic target of interest in a subgroup of migraine patients who do not respond to existing therapies.

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.

Calcitonin gene-related peptide in migraine: from pathophysiology to treatment

INTRODUCTION

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.

DEVELOPMENT

The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.

CONCLUSIONS

The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.

Treatment of resistant chronic migraine with anti-CGRP monoclonal antibodies: a systematic review

Background

Resistant chronic migraine is a highly disabling condition which is very difficult to treat. The majority of the treatments for migraine prophylaxis are nonspecific and present weak safety profiles, leading to low adherence and discontinuation. Currently, monoclonal antibodies (mAb) targeting the trigeminal sensory neuropeptide, calcitonin gene-related peptide (CGRP), are available for migraine prophylaxis being the first drugs developed specifically to target migraine pathogenesis. The main objective of the current work is to carry out a systematic review of randomised controlled trials that specifically analyse the effectivity and safety of anti-CGRP mAb, comparatively to placebo, in patients with resistant chronic migraine and possibly fill the literature gap or be a source of information to health professionals. Additionally the current knowledge on migraine, particularly resistant chronic migraine, was revisited and summarised.

Methods

Literature search was carried out on MEDLINE, Scopus, Science Direct and ClinicalTrials.gov database, from inception to December 2021. Articles were selected according to prespecified criteria of inclusion and exclusion. Efficacy and safety outcomes included were: change from baseline in monthly migraine days (MMD); ≥50% reduction of MMD values from baseline; change from baseline in monthly acute migraine-specific medication days (MAMD); Migraine-specific Quality of Life Questionnaire (MSQ); and registered adverse events. Additionally, we used the Cochrane risk of bias tool (RoB 2) to assess the risk of bias of the included studies.

Results

Four studies were included in this systematic review, involving 2811 resistant chronic migraine patients, 667 in a study using erenumab, 838 in a study using fremanezumab and 1306 in two studies using galcanezumab. When compared to placebo, all investigated anti-CGRP mAb and respective doses demonstrate effectiveness in decreasing MMD, reducing acute medication use and improving the MSQ scores, including, sometimes, reversion of chronic to episodic migraine (efficacy outcomes). Regarding the safety outcomes, the number and type of adverse events did not differ between anti-CGRP mAb-treated and placebo groups.

Conclusions

Anti-CGRP or anti-CGRP receptor monoclonal antibodies are a promising preventive migraine therapy which can be particularly useful for resistant chronic migraine patients.

Calcitonin gene-related peptide in migraine: from pathophysiology to treatment

INTRODUCTION

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.

DEVELOPMENT

The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.

CONCLUSIONS

The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.

Brazilian descriptive study of 104 consecutive real-world migraine patients treated with monoclonal antibodies

BACKGROUND

Migraine is a highly disabling and prevalent neurological disorder. A peptide, calcitonin gene-related peptide, was identified as involved in migraine pathophysiology and monoclonal anti-CGRP antibodies have been developed.

AIM

To describe the clinical characteristics and therapeutic response of migraine patients treated with monoclonal antibodies.

METHOD

An observational, prospective, uncontrolled and descriptive study was carried out with a sample of 112 consecutive patients with episodic or chronic migraine treated with monoclonal antibodies. Eight patients did not return for the following medical consultation. They were excluded from the study.

RESULTS

A total of 104 patients were described. There was a predominance of episodic migraine. Before treatment, the average frequency of headache was 15.3±8.5 days per month, during the previous three months. Monoclonal antibodies were prescribed at the following frequency: erenumab (49%), galcanezumab (45.2%), and fremanezumab (5.8%). After the third month, the reduction in headache attacks was greater than 50% in 57.7% of patients. Adverse events were referred by 18.3% of patients, in this order of frequency: constipation (7.7%), insomnia (2.9%), vertigo (1.9%), erythema at the injection site (1.9%), arthralgia (1%), nasopharyngitis (1%), facial and hand edema (1%), irritation at the injection site (1%), and paresthesia at the injection site (1%).

CONCLUSIONS

This described analysis of migraine patients who used monoclonal antibodies presented one of the first Brazilian experiences with real-world patients. Our results may enlighten clinicians on the outcomes and ways of prescribing anti-CGRP antibodies.

CGRP Targeting Therapy for Chronic Migraine-Evidence from Clinical Trials and Real-world Studies

PURPOSE OF REVIEW

Monoclonal antibodies against calcitonin gene-related peptide (CGRP) or its receptor have become part of the standard treatment for migraine in clinical practice. The current review focuses on the clinical evidence of CGRP monoclonal antibodies in patients with chronic migraine (CM), including more challenging cases.

RECENT FINDINGS

CGRP monoclonal antibodies were more effective than placebo in reducing the number of monthly migraine days (MMDs), and the change relative to placebo in the treatment group was between - 1.2 and - 2.7 days at 3 months. CGRP monoclonal antibodies resulted in ≥ 50% response in 27.5 to 61.4% of patients, and doubled the odds for having ≥ 50% response. The findings were generally consistent in patients with coexisting medication overuse or with treatment failures to multiple preventive medications, including onabotulinumtoxinA. The results from real-world studies (RWS) were similar to those seen in clinical trials, and the changes from baseline in the number of MMDs and the response rates largely fell within the ranges of those reported in the treatment group in pivotal trials. The therapeutic effects typically started within a few days, and remained steady after regular treatment for up to 1 year. These agents were generally well tolerated, and the discontinuation rates due to adverse events in clinical trials and in many RWS were < 4.5%. CGRP monoclonal antibodies are effective and safe in the treatment of patients with CM, including clinical challenging cases. However, the role of CGRP monoclonal antibodies in a number of conditions, such as cardiovascular or cerebrovascular diseases, pregnancy, and overuse of opioids or barbiturates, needs to be further clarified.

Calcitonin Gene-Related Peptide (CGRP)-Targeted Monoclonal Antibodies and Antagonists in Migraine: Current Evidence and Rationale

Calcitonin gene-related peptide (CGRP), a 37 amino-acid neuropeptide found mostly in peptidergic sensory C-fibers, has been suggested to be implicated in the pathogenesis of migraine, which is one of the most common neurological disorders seen in medical practice, affecting almost 16% of the US population. While previously thought to be a vascular condition, migraine attacks are the result of neurogenic inflammation and peripheral/central sensitization through dysfunctional activation of the trigeminovascular system. To date, two classes of therapeutic agents have been developed to interrupt the function of CGRP: CGRP-targeted monoclonal antibodies (mAbs) and small-molecule antagonists (gepants). There are currently four CGRP-targeted mAbs and three gepants that are US Food and Drug Administration (FDA) approved for the treatment of migraine. Multiple phase II and III studies have established the efficacies and tolerability of these treatments. Previously, we reviewed the fundamental role of CGRP in migraine pathogenesis. Here, we discuss in depth the clinical evidence (randomized controlled trials and real-world studies), safety, and tolerability of CGRP-targeted mAbs and gepants for treating migraine.

Outcomes That Matter to Adolescents With Continuous Headache Due to Chronic Migraine and Their Parents: A Pilot Survey Study

BACKGROUND

Children and adolescents with chronic migraine who have continuous headache may have high levels of headache-related disability but have largely been excluded from clinical trials. Understanding patient-valued treatment outcomes may facilitate future study design.

OBJECTIVE

To identify patient-valued outcome measures for headache preventive treatments among adolescents with continuous headache due to chronic migraine and their parents.

METHODS

Adolescents with an ICHD-3 diagnosis of chronic migraine, who had continuous headache and who were being cared for at a tertiary pediatric headache clinic, and their parents, were surveyed to query the value of treatment outcomes in the domains of headache frequency, intensity, functional impact, and associated symptoms. Individual outcomes and categories of outcomes were ranked in order of preference using weighted average rank. Results were rounded to the degree of precision with which they were measured.

RESULTS

The survey was completed by 55 adolescents and 60 parents of adolescents with continuous headache due to chronic migraine. Mean age of adolescents was 16 (SD 1, range 12 to 17). Median adolescent-reported duration of continuous headache was 24 months (IQR 12-39) and adolescents had tried a median (IQR) of 2 (0-5) preventive medications, only 13% of which were perceived as helpful. Overall, the most valued individual outcome measure among both adolescents and parents was a decrease in frequency of more severe headaches; however, outcomes reflecting headache intensity were most valued by adolescents while outcomes reflecting functional impact were most valued by parents. Over 60% of adolescents felt that it was more important to measure decrease in frequency and intensity of headaches in terms of severe headaches/spikes rather than total headache days. Among associated symptoms, improvement in "brain fog" was most highly valued by both adolescents and parents.

DISCUSSION

The results of this study provide important information about which preventive treatment outcomes are valued by adolescents with continuous headache due to chronic migraine and their parents. Results suggest that adolescents value a decrease in frequency of severe headaches over a decrease in frequency of headache days overall. Generalizability may be limited as the surveyed population were being cared for at a tertiary pediatric headache clinic and generally had headache disorders that were refractory to treatment. These results may help guide future trial design in this population with continuous headache due to chronic migraine.

TRIAL REGISTRATION

NA.

The importance of an early onset of migraine preventive disease control: A roundtable discussion

Background:

Newly approved migraine preventive therapies have allowed for rapid control of migraine activity, offering potential to minimize the burden of migraine. This report summarizes a roundtable discussion convened to analyze evidence for early onset of prevention, ascertain its clinical relevance, and provide guidance for healthcare professionals in crafting goals and treatment expectations for patients with migraine initiating preventive therapy.

Methods:

A virtual roundtable meeting of migraine clinicians, researchers, and patient advocates convened in October 2020. Participants reviewed and discussed data summarizing patient and healthcare professional perceptions of migraine prevention and evidence from the peer-reviewed and gray literature to develop corresponding recommendations.

Summary:

Evidence from clinical studies of anti-calcitonin gene-related peptide monoclonal antibodies (erenumab, fremanezumab, galcanezumab, and eptinezumab) and the chemodenervation agent onabotulinumtoxinA indicate that patients may experience reduction of migraine activity within 7 days of drug administration and early attainment of disease control is associated with improvements in clinically important outcomes. The roundtable of experts proposes that early onset be defined as demonstration of preventive benefits within 1 week of treatment initiation. We recommend focusing discussion with patients around “disease control” and potential benefits of early onset of prevention, so patients can set realistic preventive therapy goals and expectations.

Real-world impact of fremanezumab on migraine symptoms and resource utilization in the United States

Background

Fremanezumab, a fully humanized monoclonal antibody (IgG2Δa) that selectively targets calcitonin gene-related peptide (CGRP), is approved for migraine prevention in adults. Real-world data on the effectiveness of fremanezumab are limited. This retrospective, observational cohort study assessed patient-reported migraine symptoms, health care resource utilization (HCRU), and direct medical costs before and after fremanezumab treatment initiation.

Methods

Data were extracted from September 2018 through June 2020 from the Midwest component of EMRClaims+®, an integrated health services database containing > 20 million medical records from national commercial insurance claims, Medicare claims, and regional electronic medical records. Patients included in the cohort analysis were aged ≥ 18 years and were administered fremanezumab, with enrollment or treatment history for ≥ 6 months prior (pre-index) to initiating fremanezumab (index date) and ≥ 1 month after the index date (post-index), and without pregnancy or pregnancy-related encounters during the study period. Patient-reported headache frequency, migraine pain intensity (MPI), composite migraine symptoms, and HCRU were assessed pre-index and ≥ 1 month after fremanezumab initiation. Wilcoxon signed-rank tests were used to compare means of migraine symptoms and outcomes and HCRU before and after fremanezumab initiation.

Results

Overall, 172 patients were eligible for analysis. Of patients who self-reported (n = 129), 83.7% reported improvement in headache frequency or symptoms after fremanezumab treatment. Specifically, headache frequency decreased by 63% after fremanezumab initiation: mean (standard deviation) headache frequency was 22.24 (9.29) days per month pre-index versus 8.24 (7.42) days per month post-index (P < 0.0001). Mean MPI also decreased by 18% after fremanezumab initiation: MPI was 5.47 (3.19) pre-index versus 4.51 (3.34) post-index (P = 0.014). Mean emergency room (ER) visits per month decreased from 0.72 to 0.54 (P = 0.003), and mean outpatient visits per month decreased from 1.04 to 0.81 (P < 0.001). Mean hospitalizations per month decreased, but the results did not reach statistical significance (P = 0.095). Hospitalization and ER costs decreased, while outpatient costs increased, from pre-index to post-index, but differences were not statistically significant (P ≥ 0.232).

Conclusions

Significant reductions in headache frequency, MPI, and HCRU were observed after fremanezumab initiation in patients with migraine in a US real-world setting.

CGRP monoclonal antibodies in migraine: an efficacy and tolerability comparison with standard prophylactic drugs

BACKGROUND

Several drugs are available for the preventive treatment of both episodic and chronic migraine. The choice of which therapy to initiate first, second, or third is not straightforward and is based on multiple factors, including general efficacy, tolerability, potential for serious adverse events, comorbid conditions, and costs. Recently, a new class of migraine preventive drugs was introduced, i.e. monoclonal antibodies against calcitonin gene-related peptide (CGRP) or its receptor.

METHODS

The present article summarizes the evidence gathered with this new migraine preventive drug class from randomized placebo-controlled clinical trials. It further puts this into perspective next to the evidence gained by the most widely used agents for the prevention of episodic and chronic migraine with an emphasis on efficacy and the robustness with which this efficacy signal was obtained.

RESULTS

Although being a relatively new class of migraine preventive drugs, monoclonal antibodies blocking the CGRP pathway have an efficacy which is at least comparable if not higher than those of the currently used preventive drugs. Moreover, the robustness of this efficacy signal is substantiated by several randomized clinical trials each including large numbers of patients. In addition, because of their excellent tolerability and with long-term safety data emerging, they seem to have an unprecedented efficacy over adverse effect profile, clearly resulting in an added value for migraine prevention.

CONCLUSIONS

Balancing the data presented in the current manuscript with additional data concerning long term safety on the one hand and cost issues on the other hand, can be of particular use to health policy makers to implement this new drug class in the prevention of migraine.

Anti-CGRP monoclonal antibodies in chronic migraine with medication overuse: real-life effectiveness and predictors of response at 6 months

Background

In daily practice, anti-CGRP monoclonal antibodies (MAbs) may be useful in chronic migraine (CM) with medication overuse (MO), but data is limited. We evaluated their effectiveness in a real-life clinical cohort.

Methods

This is a prospective study conducted in CM patients with and without medication overuse treated with monthly MAbs during 6 months (erenumab/galcanezumab). We collected headache characteristics, including acute medication intake, through an electronic diary. We compared patients (1) with and without MO at baseline, (2) with and without ongoing MO after treatment, defining MO resolution as < 10 or 15 days/month of acute medication intake, according to analgesic type, during the 6-month treatment.

Results

Of 139 CM patients completing 6-month treatment with anti-CGRP MAbs, 71.2% (99/139) had MO at baseline. After 6 months, patients with and without MO at baseline had significant and similar proportions of ≥50% reduction in migraine days/month (MO: 63.6% vs. non-MO: 57.5%, p = 0.500). 60.6% (60/99) no longer satisfied MO definition. Reduction in headache frequency compared to baseline occurred in both MO-ongoing and MO-resolution group, although those who stopped overusing had a greater improvement (headache days/month: − 13.4 ± 7.6 vs. -7.8 ± 7.2, p < 0.0001). No differences in MO resolution were observed according to the MAbs used. Baseline lower pain severity was associated with MO resolution (OR [95%]:0.236[0.054–0.975]; p = 0.049).

Conclusions

In real-life anti-CGRP MAbs are as effective in CM patients with MO as in patients without it and facilitate MO cessation. Reduction in headache frequency and acute medication days/month occurs regardless of whether patients stop overusing or not.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01328-1.

Monoclonal Antibodies for Chronic Pain Treatment: Present and Future

Chronic pain remains a major problem worldwide, despite the availability of various non-pharmacological and pharmacological treatment options. Therefore, new analgesics with novel mechanisms of action are needed. Monoclonal antibodies (mAbs) are directed against specific, targeted molecules involved in pain signaling and processing pathways that look to be very effective and promising as a novel therapy in pain management. Thus, there are mAbs against tumor necrosis factor (TNF), nerve growth factor (NGF), calcitonin gene-related peptide (CGRP), or interleukin-6 (IL-6), among others, which are already recommended in the treatment of chronic pain conditions such as osteoarthritis, chronic lower back pain, migraine, or rheumatoid arthritis that are under preclinical research. This narrative review summarizes the preclinical and clinical evidence supporting the use of these agents in the treatment of chronic pain.

The locus of Action of CGRPergic Monoclonal Antibodies Against Migraine: Peripheral Over Central Mechanisms

Migraine is a complex neurovascular disorder characterized by attacks of moderate to severe unilateral headache, accompanied by photophobia among other neurological signs. Although an arsenal of antimigraine agents is currently available in the market, not all patients respond to them. As Calcitonin Gene-Related Peptide (CGRP) plays a key role in the pathophysiology of migraine, CGRP receptor antagonists (gepants) have been developed. Unfortunately, further pharmaceutical development (for olcegepant and telcagepant) was interrupted due to pharmacokinetic issues observed during the Randomized Clinical Trials (RCT). On this basis, the use of monoclonal antibodies (mAbs; immunoglobulins) against CGRP or its receptor has recently emerged as a novel pharmacotherapy to treat migraines. RCT showed that these mAbs are effective against migraines producing fewer adverse events. Presently, the U.S. Food and Drug Administration approved four mAbs, namely: (i) erenumab; (ii) fremanezumab; (iii) galcanezumab; and (iv) eptinezumab. In general, specific antimigraine compounds exert their action in the trigeminovascular system, but the locus of action (peripheral vs. central) of the mAbs remains elusive. Since these mAbs have a molecular weight of ∼150 kDa, some studies rule out the relevance of their central actions as they seem unlikely to cross the Blood-Brain Barrier (BBB). Considering the therapeutic relevance of this new class of antimigraine compounds, the present review has attempted to summarize and discuss the current evidence on the probable sites of action of these mAbs.

Efficacy and safety of fremanezumab for episodic migraine prevention: Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial in Japanese and Korean patients

OBJECTIVE

To evaluate the efficacy and safety of two dosing regimens of fremanezumab in Japanese and Korean patients with episodic migraine.

BACKGROUND

Episodic migraine, which accounts for more than 90% of migraine cases, is inadequately addressed by widely available preventive therapies. Fremanezumab, a monoclonal antibody that selectively targets the trigeminal sensory neuropeptide calcitonin gene-related peptide involved in migraine pathogenesis, has demonstrated efficacy in international Phase 3 trials of patients with both chronic and episodic migraine.

METHODS

This Phase 3 randomized, placebo-controlled trial randomly assigned patients with episodic migraine to receive subcutaneous fremanezumab monthly (225 mg at baseline, week 4, and week 8), fremanezumab quarterly (675 mg at baseline and placebo at weeks 4 and 8), or matching placebo. The primary endpoint was the mean change from baseline in the monthly average number of migraine days during the 12-week treatment period after the first dose.

RESULTS

Of 357 patients enrolled (safety set, n = 356; full analysis set, n = 354), the least-squares mean (±standard error) reductions in the average number of migraine days per month during 12 weeks were significantly greater with fremanezumab monthly (-4.0 ± 0.4, n = 121) and fremanezumab quarterly (-4.0 ± 0.4, n = 117) than with placebo (-1.0 ± 0.4, n = 116; p < 0.0001 for both comparisons). The proportion of patients reaching at least a 50% reduction in the monthly average number of migraine days during the 12-week period after initial administration was also significantly improved with fremanezumab (fremanezumab monthly, 41.3%; fremanezumab quarterly, 45.3%; placebo, 11.2%; p < 0.0001 for both comparisons) as were other secondary endpoints (p < 0.001 for all comparisons between fremanezumab and placebo). Injection-site reactions were more common in fremanezumab-treated patients (fremanezumab monthly, 25.6%; fremanezumab quarterly, 29.7%; placebo, 21.4%).

CONCLUSION

Fremanezumab prevents episodic migraine in Japanese and Korean patients to a similar extent than in previously reported populations with no new safety concerns.

Monoclonal Antibodies Targeting CGRP: From Clinical Studies to Real-World Evidence-What Do We Know So Far?

Now more than ever is the time of monoclonal antibody use in neurology. In headaches, disease-specific and mechanism-based treatments existed only for symptomatic management of migraines (i.e., triptans), while the standard prophylactic anti-migraine treatments consist of non-specific and repurposed drugs that share limited safety profiles and high risk for interactions with other medications, resulting in rundown adherence rates. Recent advances in headache science have increased our understanding of the role of calcitonin gene relate peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) pathways in cephalic pain neurotransmission and peripheral or central sensitization, leading to the development of monoclonal antibodies (mAbs) or small molecules targeting these neuropeptides or their receptors. Large scale randomized clinical trials confirmed that inhibition of the CGRP system attenuates migraine, while the PACAP mediated nociception is still under scientific and clinical investigation. In this review, we provide the latest clinical evidence for the use of anti-CGRP in migraine prevention with emphasis on efficacy and safety outcomes from Phase III and real-world studies.

MAB-MIG: registry of the spanish neurological society of erenumab for migraine prevention

BACKGROUND

Erenumab was approved in Europe for migraine prevention in patients with ≥ 4 monthly migraine days (MMDs). In Spain, Novartis started a personalized managed access program, which allowed free access to erenumab before official reimbursement. The Spanish Neurological Society started a prospective registry to evaluate real-world effectiveness and tolerability, and all Spanish headache experts were invited to participate. We present their first results.

METHODS

Patients fulfilled the ICHD-3 criteria for migraine and had ≥ 4 MMDs. Sociodemographic and clinical data were registered as well as MMDs, monthly headache days, MHDs, prior and concomitant preventive treatment, medication overuse headache (MOH), migraine evolution, adverse events, and patient-reported outcomes (PROs): headache impact test (HIT-6), migraine disability assessment questionnaire (MIDAS), and patient global improvement change (PGIC). A > 50% reduction of MMDs after 12 weeks was considered as a response.

RESULTS

We included 210 patients (female 86.7%, mean age 46.4 years old) from 22 Spanish hospitals from February 2019 to June 2020. Most patients (89.5%) suffered from chronic migraine with a mean evolution of 8.6 years. MOH was present in 70% of patients, and 17.1% had migraine with aura. Patients had failed a mean of 7.8 preventive treatments at baseline (botulinum toxin type A-BoNT/A-had been used by 95.2% of patients). Most patients (67.6%) started with erenumab 70 mg. Sixty-one percent of patients were also simultaneously taking oral preventive drugs and 27.6% were getting simultaneous BoNT/A. Responder rate was 37.1% and the mean reduction of MMDs and MHDs was -6.28 and -8.6, respectively. Changes in PROs were: MIDAS: -35 points, HIT-6: -11.6 points, PIGC: 4.7 points. Predictors of good response were prior HIT-6 score < 80 points (p = 0.01), ≤ 5 prior preventive treatment failures (p = 0.026), absence of MOH (p = 0.039), and simultaneous BoNT/A treatment (p < 0.001). Twenty percent of patients had an adverse event, but only two of them were severe (0.9%), which led to treatment discontinuation. Mild constipation was the most frequent adverse event (8.1%).

CONCLUSIONS

In real-life, in a personalized managed access program, erenumab shows a good effectiveness profile and an excellent tolerability in migraine prevention in our cohort of refractory patients.

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.

Efficacy and safety of fremanezumab in patients with episodic and chronic migraine with documented inadequate response to 2 to 4 classes of migraine preventive medications over 6 months of treatment in the phase 3b FOCUS study

Background

Fremanezumab, a fully humanized monoclonal antibody (IgG2Δa) selectively targets the calcitonin gene-related peptide and has proven efficacy for the preventive treatment of migraine. In this study, we evaluated the long-term efficacy, safety, and tolerability of monthly and quarterly fremanezumab.

Methods

Episodic migraine and chronic migraine patients completing the 12-week double-blind period of the FOCUS trial entered the 12-week open-label extension and received 3 monthly doses of fremanezumab (225 mg). Changes from baseline in monthly migraine days, monthly headache days of at least moderate severity, days of acute headache medication use, days with photophobia/phonophobia, days with nausea or vomiting, disability scores, and proportion of patients achieving a ≥50% or  ≥75% reduction in monthly migraine days were evaluated.

Results

Of the 807 patients who completed the 12-week double-blind treatment period and entered the open-label extension, 772 patients completed the study. In the placebo, quarterly fremanezumab, and monthly fremanezumab dosing regimens, respectively, patients had fewer average monthly migraine days (mean [standard deviation] change from baseline: − 4.7 [5.4]; − 5.1 [4.7]; − 5.5 [5.0]), monthly headache days of at least moderate severity (− 4.5 [5.0]; − 4.8 [4.5]; − 5.2 [4.9]), days per month of acute headache medication use (− 4.3 [5.2]; − 4.9 [4.6]; − 4.8 [4.9]), days with photophobia/phonophobia (− 3.1 [5.3]; − 3.4 [5.3]; − 4.0 [5.2]), and days with nausea or vomiting (− 2.3 [4.6]; − 3.1 [4.5]; − 3.0 [4.4]). During the 12-week open-label extension, 38%, 45%, and 46% of patients, respectively, achieved a ≥50% reduction and 16%, 15%, and 20%, respectively, achieved a ≥75% reduction in monthly migraine days. Disability scores were substantially improved in all 3 treatment groups. There were low rates of adverse events leading to discontinuation (<1%).

Conclusion

Fremanezumab demonstrated sustained efficacy up to 6 months and was well tolerated in patients with episodic migraine or chronic migraine and documented inadequate response to multiple migraine preventive medication classes.

Trial registration

ClinicalTrials.gov NCT03308968 (FOCUS).

Monoaminergic Receptors as Modulators of the Perivascular Sympathetic and Sensory CGRPergic Outflows

Blood pressure is a highly controlled cardiovascular parameter that normally guarantees an adequate blood supply to all body tissues. This parameter is mainly regulated by peripheral vascular resistance and is maintained by local mediators (i.e., autacoids), and by the nervous and endocrine systems. Regarding the nervous system, blood pressure can be modulated at the central level by regulating the autonomic output. However, at peripheral level, there exists a modulation by activation of prejunctional monoaminergic receptors in autonomic- or sensory-perivascular fibers. These modulatory mechanisms on resistance blood vessels exert an effect on the release of neuroactive substances from the autonomic or sensory fibers that modify blood pressure. Certainly, resistance blood vessels are innervated by perivascular: (i) autonomic sympathetic fibers (producing vasoconstriction mainly by noradrenaline release); and (ii) peptidergic sensory fibers [producing vasodilatation mainly by calcitonin gene-related peptide (CGRP) release]. In the last years, by using pithed rats, several monoaminergic mechanisms for controlling both the sympathetic and sensory perivascular outflows have been elucidated. Additionally, several studies have shown the functions of many monoaminergic auto-receptors and hetero-receptors expressed on perivascular fibers that modulate neurotransmitter release. On this basis, the present review: (i) summarizes the modulation of the peripheral vascular tone by adrenergic, serotoninergic, dopaminergic, and histaminergic receptors on perivascular autonomic (sympathetic) and sensory fibers, and (ii) highlights that these monoaminergic receptors are potential therapeutic targets for the development of novel medications to treat cardiovascular diseases (with some of them explored in clinical trials or already in clinical use).

Efficacy and safety of fremanezumab for chronic migraine prevention: Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial in Japanese and Korean patients

OBJECTIVE

To determine the efficacy and safety of fremanezumab administration in Japanese and Korean patients with chronic migraine (CM).

BACKGROUND

Available preventive treatments for CM are limited by various efficacy and safety issues. Fremanezumab, a monoclonal antibody that targets the calcitonin gene-related peptide pathway involved in migraine pathogenesis, has been shown to be effective and well tolerated in large-scale, international Phase 3 trials.

METHODS

Randomized, placebo-controlled trial of patients with CM who received subcutaneous fremanezumab monthly (675 mg at baseline and 225 mg at weeks 4 and 8), fremanezumab quarterly (675 mg at baseline and placebo at weeks 4 and 8), or matching placebo. Primary endpoint was the mean change from baseline in the monthly (28-day) average number of headache days of at least moderate severity during the 12 weeks after the first dose.

RESULTS

Among 571 patients randomized (safety set, n = 569; full analysis set, n = 566), the least-squares mean (±standard error [SE]) reduction in the average number of headache days of at least moderate severity per month during 12 weeks was significantly greater with fremanezumab monthly (-4.1 ± 0.4) and fremanezumab quarterly (-4.1 ± 0.4) than with placebo (-2.4 ± 0.4). The difference from the placebo group in the mean change (95% confidence interval [CI]) was -1.7 days (-2.54, -0.80) for the fremanezumab monthly group and -1.7 days (-2.55, -0.82) for the fremanezumab quarterly group (p < 0.001 vs. placebo for both fremanezumab groups). The percentage of patients with a ≥50% reduction in the average number of headache days of at least moderate severity per month (response rate) was higher with fremanezumab monthly (29.0%) and fremanezumab quarterly (29.1%) than with placebo (13.2%) in addition to other improvements in secondary endpoints, including reduction of acute medication use (mean change from baseline during 12-week period ± SE: fremanezumab monthly, -3.7 ± 0.4; fremanezumab quarterly, -3.9 ± 0.4; placebo, -2.4 ± 0.4) and improvements in disability scores (mean change from baseline in six-item Headache Impact Test score at 4 weeks after third injection ± SE: fremanezumab monthly, -8.1 ± 0.7; fremanezumab quarterly, -8.0 ± 0.7; placebo, -6.5 ± 0.7). Fremanezumab was well tolerated with a similar incidence of adverse events including injection-site reactions as placebo (patients with at least one treatment-emergent adverse event: fremanezumab total, n = 232 [61.4%]; placebo, n = 118 [61.8%]).

CONCLUSION

Fremanezumab effectively prevents CM in Japanese and Korean patients and was well tolerated. No safety signal was detected.

CGRP-antibodies, topiramate and botulinum toxin type A in episodic and chronic migraine: A systematic review and meta-analysis

Background

The approval of monoclonal antibodies for prevention of migraine has revolutionized treatment for patients. Oral preventatives are still considered first line treatments as head-to-head trials comparing them with antibodies are lacking.

Methods

The main purpose of this study was to provide a comparative overview of the efficacy of three commonly prescribed migraine preventative medication classes. For this systematic review and meta-analysis, we searched the databases CENTRAL, EMBASE, and MEDLINE until 20 March 2020. We included RCTs reporting the 50% response rates for topiramate, Botulinum Toxin Type A and monoclonal antibodies against CGRP(r). Studies were excluded if response rates were not reported, treatment allocation was unclear, or if study quality was insufficient. Primary outcome measure were the 50% response rates. The pooled odds ratios with 95% confidence intervals were calculated with the random effects model. The study was registered at PROSPERO (CRD42020222880).

Findings

We identified 6552 reports. Thirty-two were eligible for our review. Studies assessing monoclonal antibodies included 13,302 patients and yielded pooled odds ratios for the 50% response rate of 2.30 (CI: 2.11–2.50). Topiramate had an overall effect estimate of 2.70 (CI: 1.97–3.69) with 1989 included patients and Botulinum Toxin Type A achieved 1.28 (CI: 0.98–1. 67) with 2472 patients included.

Interpretation

Topiramate, botulinum toxin type A and monoclonal antibodies showed higher odds ratios in achieving a 50% response rate compared to placebo. Topiramate numerically demonstrated the greatest effect size but also the highest drop-out rate.

Different routes of administration in chronic migraine prevention lead to different placebo responses: a meta-analysis

ABSTRACT

Placebo response is a powerful determinant of health outcomes in several disorders. Meta-analysis of clinical trials in pain conditions shows that it can contribute up to 75% of the overall treatment effect. Placebo response deriving from different routes of administration is poorly understood in primary headaches' pharmacological prevention. Thus, this meta-analysis aims to analyze how different routes of administration affect the placebo response in chronic migraine (CM). We conducted a meta-analysis with 7 randomized, double-blind, placebo-controlled clinical trials, with 5672 patients older than 18 years who suffer from CM without associated comorbidities. We compared those who received a placebo-administered agent for the preventive treatment of CM subcutaneous, endovenous, or oral against those who received multiple head injections. The primary outcome was reduction in the number of days with migraine in the month assessed at 12, 16, and 24 weeks of treatment compared with baseline. Our study shows that placebo responses were greater when botulinum toxin was applied to the head, followed by intravenous injection of the anti-calcitonin gene-related peptide monoclonal antibody eptinezumab. Oral topiramate and subcutaneous monoclonal showed no difference, being inferior to head injection. Administration route affects placebo responses in CM preventive treatment. Elucidating the underlying mechanisms that mediate a placebo response in migraine treatment is beneficial to clinical practice and drug development, especially when comparing drugs with different routes of administration, with the effect of application to the head being superior to the other routes in this study. In our study the placebo response accounted for approximately 75% of the therapeutic gain in the treatment of CM.

Scaling Approaches for Pediatric Dose Selection: The Fremanezumab (AJOVY®) Journey to Select a Phase 3 Dose Using Pharmacokinetic Data from a Phase 1 Study

Fremanezumab, a fully humanized IgG2Δa/kappa monoclonal antibody, selectively targets the calcitonin-gene-related peptide (CGRP) and prevents it from binding to the CGRP receptor. The safety, tolerability, pharmacokinetics (PK), and efficacy of fremanezumab for treating migraines administered as a once monthly 225 mg dose or a once quarterly 675 mg dose have been well characterized in adults. The fremanezumab exposure and body weight relationship supported the use of the approved 225 mg monthly adult dose for pediatric patients weighing ≥45 kg. In the pediatric Phase 3 program, a 120 mg dose for patients weighing <45 kg was determined using the results of an open-label study and a population PK modeling and simulation strategy. A thorough evaluation was conducted to further characterize the population PK of fremanezumab and assess the predictive performance of the adult population PK model when applied to the Phase 1 pediatric data, the predictive performance of alternative pediatric population PK models, and the predictive performance of the selected pediatric population PK model via a noncompartmental-based approach. This latter comparison to noncompartmental results provided additional evidence that the pediatric population PK model predicts the observed data well and supports the 120 mg monthly dose in patients weighing <45 kg.

Calcitonin Gene-Related Peptide Monoclonal Antibody Versus Botulinum Toxin for the Preventive Treatment of Chronic Migraine: Evidence From Indirect Treatment Comparison

Background: The previously approved botulinum toxin and nowadays promising calcitonin gene-related peptide (CGRP) monoclonal antibody have shown efficacy for preventing chronic migraine (CM). However, there is no direct evidence for their relative effectiveness and safety. In this study, we conducted an indirect treatment comparison to compare the efficacy and safety of CGRP monoclonal antibody with botulinum toxin for the preventive treatment of chronic migraine.

Methods: Up to August 31, 2020, we systematically searched PubMed, Embase, and Cochrane Library Central Register of Controlled Trials (Central). Weighted mean difference (WMD) and relative risk (RR) were used to evaluate clinical outcomes. Indirect treatment comparison (ITC) software was used to conduct indirect treatment comparison.

Results: Ten studies were pooled with 6,325 patients in our meta-analysis. Both botulinum toxin and CGRP monoclonal antibody demonstrated favorable efficacy in the change of migraine days, headache days, HIT-6 score, and 50% migraine responder rate compared with placebo. In indirect treatment comparison, CGRP monoclonal antibody was superior to botulinum toxin in the frequency of acute analgesics intake (WMD = −1.31, 95% CI: −3.394 to 0.774, p = 0.02113), the rate of treatment-related adverse events (AEs) (RR = 0.664, 95% CI: 0.469 to 0.939, p = 0.04047), and the rate of treatment-related serious adverse events (RR = 0.505, 95% CI: 0.005 to 46.98, p < 0.001).

Conclusion: For chronic migraine patients, CGRP monoclonal antibody was slightly better than botulinum toxin in terms of efficacy and safety. In the future, head-to-head trials would be better to evaluate the efficacy and safety between different medications in the prevention of chronic migraine.

Effects of fremanezumab in patients with chronic migraine and comorbid depression: Subgroup analysis of the randomized HALO CM study

Objective

To evaluate the efficacy of fremanezumab in patients with chronic migraine (CM) and moderate to severe depression.

Background

Fremanezumab, a fully humanized monoclonal antibody that selectively targets calcitonin gene–related peptide, has been approved for the preventive treatment of migraine in adults. CM and depression are highly comorbid.

Methods

The 12‐week, Phase 3 HALO trial randomized patients with CM to fremanezumab quarterly (675 mg/placebo/placebo), fremanezumab monthly (675/225/225 mg), or placebo. Post hoc analyses evaluated the effects of fremanezumab in patients with moderate to severe depression (baseline 9‐item Patient Health Questionnaire sum score ≥10) on monthly number of headache days of at least moderate severity; monthly migraine days; Patient Global Impression of Change (PGIC); 6‐item Headache Impact Test (HIT‐6) scores; and depression.

Results

For the 219/1121 (19.5%) patients with moderate to severe depression at baseline, fremanezumab was associated with a significant reduction in monthly number of headache days of at least moderate severity for active treatment versus placebo (least‐squares mean change ± standard error for quarterly dosing: −5.3 ± 0.77; for monthly dosing: −5.5 ± 0.72; and for placebo: −2.2 ± 0.81; both p < 0.001). More patients achieved a ≥50% reduction in headache days of at least moderate severity with fremanezumab (quarterly: 31/78 [39.7%]; monthly: 39/96 [40.6%]) than placebo (9/67 [13.4%]; both p < 0.001). Compared with placebo, fremanezumab improved PGIC and HIT‐6 scores.

Conclusions

Fremanezumab demonstrated efficacy in the preventive treatment of CM and reduced headache impact in patients with comorbid depression.