Mode and site of action of therapies targeting CGRP signaling

CaV3.2 T-type calcium channels contribute to CGRP- induced allodynia in a rodent model of experimental migraine

BACKGROUND

Migraine is a painful neurological syndrome characterized by attacks of throbbing headache, of moderate to severe intensity, which is associated with photo- and phono- sensitivity as well as nausea and vomiting. It affects about 15% of the world's population being 2-3 times more prevalent in females. The calcitonin gene-related peptide (CGRP) is a key mediator in the pathophysiology of migraine, and a significant advance in the field has been the development of anti-CGRP therapies. The trigeminal ganglion (TG) is thought to be an important site of action for these drugs. Moreover, experimental migraine can be induced by CGRP injection in the TG. The signaling pathway induced by CGRP in the TG is not fully understood, but studies suggest that voltage-gated calcium channels contribute to CGRP effects relevant to migraine.

OBJECTIVE

We hypothesised that CGRP injection in the TG enhances CaV3.2 T-type calcium channel currents to contribute to the development of periorbital mechanical allodynia.

RESULTS

A Co-Immunoprecipitation assay in tsA-201 cells revealed that CaV3.2 channels form a complex with RAMP-1, a component of the CGRP receptor. Constitutive CGRPR activity was able to inhibit CaV3.2 channels and induce a depolarizing shift in both activation and inactivation curves. Incubation of TG neurons with CGRP increased T-type current density by ~ 3.6 fold, an effect that was not observed in TG neurons from CaV3.2 knockout mice. Incubation of TG neurons with Z944, a pan T-type channel blocker, resulted in an approximately 80% inhibition of T-type currents. In vivo, this treatment abolished the development of periorbital mechanical allodynia induced by CGRP in male and female mice. Likewise, CaV3.2 knockout mice did not develop periorbital mechanical allodynia after intraganglionic CGRP injection. Finally, we demonstrated that the CGRP effect depends on the activation of its canonical GPCR, followed by protein kinase A activation.

CONCLUSION

The present study suggests that CGRP modulates CaV3.2 in the TG, an effect possibly mediated by the canonical CGRP receptor and PKA activation. The increase in T-type currents in the TG may represent a contributing factor for the initiation and maintenance of the headache pain during migraine.

Combining treatments for migraine prophylaxis: the state-of-the-art

Combination treatments for migraine prophylaxis present a promising approach to addressing the diverse and complex mechanisms underlying migraine. This review explores the potential of combining oral conventional prophylactics, onabotulinumtoxin A, monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway, and small molecule CGRP receptor antagonists (gepants). Among the most promising strategies, dual CGRP inhibition through mAbs and gepants may enhance efficacy by targeting both the CGRP peptide and its receptor, while the combination of onabotulinumtoxin A with CGRP treatments offers synergistic pain relief. Oral non-CGRP treatments, which are accessible and often prescribed for patients with comorbid conditions, provide an affordable and practical option in combination regimens. Despite the potential of these combinations, there is a lack of evidence to support their widespread inclusion in clinical guidelines. The high cost of certain combinations, such as onabotulinumtoxin A with a CGRP mAb or dual anti-CGRP mAbs, presents feasibility challenges. Further large-scale trials are needed to establish safe and effective combination protocols and solidify their role in clinical practice, particularly for treatment-resistant patients.

Rimegepant for the acute and preventive treatment of migraine: a narrative review of the evidence

INTRODUCTION

Rimegepant is an oral small-molecule calcitonin gene-related peptide receptor antagonist approved in several countries for acute treatment of migraine and preventive treatment of episodic migraine in adults. This review summarizes the evidence, published to date, for the use of rimegepant as an acute or preventive treatment of migraine.

AREAS COVERED

A brief overview of migraine, the pharmacokinetics of rimegepant, and the mechanism of action of rimegepant are provided. Evidence evaluating rimegepant as an acute or preventive treatment of migraine is then summarized in more detail, based on a literature search for full-length publications related to clinical or real-world use of rimegepant.

EXPERT OPINION

Several clinical trials established rimegepant as a safe and effective treatment (acute and preventive) of migraine in adults. There are few head-to-head studies with other migraine treatments to determine relative efficacy. However, the favorable safety profile of rimegepant makes it appropriate for many patients, particularly those with contraindication, intolerance, or inadequate response to other classes of standard-of-care migraine treatments. Additional studies on the efficacy and cost-effectiveness relative to other treatments may further define the role of rimegepant in migraine treatment.

Anti‑CGRP monoclonal antibodies in resistant migraine: preliminary real-world effectiveness and clinical predictors of response at two years

BACKGROUND

Monoclonal antibodies targeting calcitonin gene-related peptide (anti-CGRP mAbs) have shown clinical effectiveness and safety in randomized clinical studies. However, long-term studies in clinical practice remain limited.

AIM

To assess the long-term effectiveness, clinical predictors and safety of three anti-CGRP mAbs (erenumab, galcanezumab, fremanezumab) in resistant migraine patients.

METHOD

A single-center retrospective study was conducted from December 2019 to June 2023 involving 120 resistant migraine patients who received at least a month of anti-CGRP mAbs treatment. Patients completed a headache diary that included monthly acute medication intake (MAM), monthly migraine days (MMD), adverse events as well as completed Patient-Reported Outcome questionnaires (MIDAS [Migraine Disability Assessment] and Headache Impact Test 6 [HIT-6]). The number of patients achieving a ≥ 50% reduction in monthly migraine days was determined and classified as ≥ 50% responders, and baseline parameters and logistic regression between responders and non-responders were analyzed to identify potential predictors of response. Adverse events were registered in every follow-up.

RESULTS

Treatment with anti-CGRP mAbs led to reductions in MIDAS, HIT-6, MMD and MAM from baseline to 6-24 months. At 6-12 months, responders (61% and 57%, respectively) exhibited lower baseline MMD and MAM. Medication overuse  was associated with non-responders from 6 to 24 months and it was identified as a negative predictor of treatment effectiveness (OR 0.23, 95% CI 0.07-0.74; p = 0.014).

CONCLUSION

Anti-CGRP mAbs prove effectiveness and safety over a 24-month period in a RM population. Patients with no medication overuse and lower basal MMDs and MAM may respond better to anti-CGRP mAbs.

Magnetoencephalography studies in migraine and headache disorders: A systematic review

BACKGROUND

Understanding the neural mechanisms underlying migraine and other primary headache disorders is critical for the development of long-term cures. Magnetoencephalography (MEG), an imaging modality that measures neuronal currents and cortical excitability with high temporal and superior spatial resolution, has been increasingly used in neurological research. Initial MEG studies showed promise in directly recording cortical spreading depression-a cortical correlate of migraine with aura. However, lately MEG technology has highly evolved with greater potential to reveal underlying pathophysiology of migraine and primary headache disorders, and aid in the identification of biomarkers.

OBJECTIVE

To systematically review the use of MEG in migraine and other primary headache disorders and summarize findings.

METHODS

We conducted a systematic search and selection of MEG studies in migraine and primary headache disorders from inception until June 8, 2023, in Medline, Embase, Cochrane, and Scopus databases. Peer-reviewed English articles reporting the use of MEG for clinical or research purposes in migraine and primary headache disorders were selected.

RESULTS

We found 560 articles and included 38 in this review after screening. Twelve studies investigated resting-state, while others investigated a sensory modality using an evoked or event-related paradigm with a total of 35 cohort and 3 case studies. Thirty-two studies focused exclusively on migraine, while the rest reported other primary headache disorders.

CONCLUSION

The findings show an evolution of MEG from a 7- to a 306-channel system and analysis evolving from sensor-level evoked responses to more advanced source-level connectivity measures. A relatively few MEG studies portrayed migraine and primary headache disorders as a sensory abnormality, especially of the visual system. We found heterogeneity in the datasets, data reporting standards (due to constantly evolving MEG technology and analysis methods), and patient characteristics. Studies were inadequately powered and there was no evidence of blinding procedures to avoid selection bias in case-control studies, which could have led to false-positive findings. More studies are needed to investigate the affective-cognitive aspects that exacerbate pain and disability in migraine and primary headache disorders.

Rimegepant and atogepant: novel drugs providing innovative opportunities in the management of migraine

INTRODUCTION

Rimegepant and atogepant, two innovative oral medications for the treatment of migraine, are gaining prominence in the treatment of migraine. However, outside of specialist headache centers, these novel medications remain subjectively underutilized. While multiple rationales exist describing their underutilization, a leading factor is the complexity and clinical flexibility attributed to the individual members of the gepant medication class.

AREAS COVERED

This review provides a brief review of the current uses, common adverse events, and potential areas of future clinical innovation attributed to rimegepant and atogepant. A database search for the term 'Rimegepant OR Atogepant' was completed, yielding 240 individual results. Following multiple rounds of assessment that aimed to determine relevance of each individual result, 42 studies were included in the synthesis of this review.

EXPERT OPINION

Rimegepant and atogepant are exciting medications that demonstrate significant clinical innovation within the field of migraine therapy. While current indications are clear, data is lacking regarding the future expanded roles of these medications. Current areas of potential therapeutic innovation for rimegepant and atogepant include the pediatric population, in pregnancy and breastfeeding, in cluster headache and post-traumatic headache, and in patients that previously discontinued calcitonin gene-related peptide (CGRP) monoclonal antibody (mAb) therapy.

Understanding the efficacy and tolerability of migraine treatment: a deep dive into CGRP antagonists

INTRODUCTION

The discovery of the role of the calcitonin gene-related peptide (CGPR) in migraine pathogenesis ushered in a new era in headache medicine. This evidence led to the development of small-molecule CGRP receptor antagonists and monoclonal antibodies targeting either CGRP or its receptor.

AREAS COVERED

We will present selected aspects of the role of CGRP in the pathogenesis of migraine, the efficacy of CGRP-targeted treatment, and the still-open questions regarding the practical application of CGRP antagonists in headache medicine.

EXPERT OPINION

CGRP-targeting drugs represent a transformative approach to migraine treatment, offering superior efficacy and tolerability compared to traditional therapies, they are a helpful addition to the treatment arsenal but also have their flaws and require further observation. Their availability provides new hope for migraine patients, particularly those who have not responded adequately to conventional treatments. Future directions for migraine care planning, especially for chronic migraine and medication-overuse headache, should include universal access to these specific and effective forms of therapy to prevent complications from the disease and its negative effects in many aspects of a patient's life.

Hallmarks of primary headache: part 1 - migraine

BACKGROUND AND AIM

Migraine is a common disabling conditions which, globally, affects 15.2% of the population. It is the second cause of health loss in terms of years lived with disability, the first among women. Despite being so common, it is poorly recognised and too often undertreated. Specialty centres and neurologists with specific expertise on headache disorders have the knowledge to provide specific care: however, those who do not regularly treat patients with migraine will benefit from a synopsis on the most relevant and updated information about this condition. This paper presents a comprehensive view on the hallmarks of migraine, from genetics and diagnostic markers, up to treatments and societal impact, and reports the elements that identify migraine specific features.

MAIN RESULTS

The most relevant hallmark of migraine is that it has common and individual features together. Besides the known clinical manifestations, migraine presentation is heterogeneous with regard to frequency of attacks, presence of aura, response to therapy, associated comorbidities or other symptoms, which likely reflect migraine heterogeneous genetic and molecular basis. The amount of therapies for acute and for prophylactic treatment is really wide, and one of the difficulties is with finding the best treatment for the single patient. In addition to this, patients carry out different daily life activities, and might show lifestyle habits which are not entirely adequate to manage migraine day by day. Education will be more and more important as a strategy of brain health promotion, because this will enable reducing the amount of subjects needing specialty care, thus leaving it to those who require it in reason of refractory condition or presence of comorbidities.

CONCLUSIONS

Recognizing the hallmarks of migraine and the features of single patients enables prescribing specific pharmacological and non-pharmacological treatments. Medical research on headaches today particularly suffers from the syndrome of single-disease approach, but it is important to have a cross-sectional and joint vision with other close specialties, in order to treat our patients with a comprehensive approach that a heterogeneous condition like migraine requires.

A real-world adverse events study of rimegepant from the FAERS database

BACKGROUND

The primary objective of this research is to conduct an exhaustive evaluation of rimegepant with the Food and Drug Administration Adverse Event Reporting System (FAERS) repository.

RESEARCH DESIGN AND METHODS

This study downloaded the reporting files related to rimegepant from the second quarter of 2020 to the first quarter of 2024. Disproportionality analysis was utilized to explore the relationship between rimegepant and adverse drug events (ADEs).

RESULTS

This study analyzed 6659 ADE reports associated with rimegepant as the primary suspected (PS) drug. In the disproportionate analysis of system organ classes (SOCs), the significant signal for rimegepant was general disorders and administration site conditions.On the preferred terms level, 35 ADEs were identified following the exclusion. The top five ADEs with high signal strengths were medication overuse headache, nasal edema, tension headache, performance status decreased, and motion sickness. The most frequent ADEs were nausea, feeling abnormal, abdominal pain upper, somnolence, and hypersensitivity. In addition, we need to pay attention to the ADEs not mentioned in the instruction and clinically significant: vertigo, hyperacusis, somnolence, Raynaud's phenomenon, motion sickness, panic attack, and fear.

CONCLUSIONS

This study highlights previously unrecognized safety concerns associated with the use of rimegepant. These novel safety aspects suggest that while these treatments can be effective, additional risks may need further exploration.

The role of nitric oxide and neuroendocrine system in pain generation

Previous studies have indicated a complex interplay between the nitric oxide (NO) pain signaling pathways and hormonal signaling pathways in the body. This article delineates the role of nitric oxide signaling in neuropathic and inflammatory pain generation and subsequently discusses how the neuroendocrine system is involved in pain generation. Hormonal systems including the hypothalamic-pituitary axis (HPA) generation of cortisol, the renin-angiotensin-aldosterone system, calcitonin, melatonin, and sex hormones could potentially contribute to the generation of nitric oxide involved in the sensation of pain. Further research is necessary to clarify this relationship and may reveal therapeutic targets involving NO signaling that alleviate neuropathic and inflammatory pain.

Calcitonin gene-related peptide and intermedin induce phosphorylation of p44/42 MAPK in primary human lymphatic endothelial cells in vitro

Calcitonin gene-related peptide (CGRP) and adrenomedullin 2/intermedin (AM2/IMD) play important roles in several pathologies, including cardiovascular disease, migraine and cancer. The efficacy of drugs targeting CGRP signalling axis for the treatment of migraine patients is sometimes offset by side effects (e.g. inflammation and microvascular complications, including aberrant neovascularisation in the skin). Recent studies using animal models implicate CGRP in lymphangiogenesis and lymphatic vessel function. However, whether CGRP or AM2/IMD can act directly on lymphatic endothelial cells is unknown. Here, we found that CGRP and AM2/IMD induced p44/42 MAPK phosphorylation in a time- and dose-dependent manner in primary human dermal lymphatic endothelial cells (HDLEC) in vitro, and thus directly affected these cells. These new findings reveal CGRP and AM2/IMD as novel regulators of LEC biology and warrant further investigation of their roles in the context of pathologies associated with lymphatic function in the skin and other organs, and therapies targeting CGRP signalling axis.

Voltage-gated Calcium Channels as Potential Therapeutic Targets in Migraine

Migraine is a complex and highly incapacitating neurological disorder that affects around 15% of the general population with greater incidence in women, often at the most productive age of life. Migraine physiopathology is still not fully understood, but it involves multiple mediators and events in the trigeminovascular system and the central nervous system. The identification of calcitonin gene-related peptide as a key mediator in migraine physiopathology has led to the development of effective and highly selective antimigraine therapies. However, this treatment is neither accessible nor effective for all migraine sufferers. Thus, a better understanding of migraine mechanisms and the identification of potential targets are still clearly warranted. Voltage-gated calcium channels (VGCCs) are widely distributed in the trigeminovascular system, and there is accumulating evidence of their contribution to the mechanisms associated with headache pain. Several drugs used in migraine abortive or prophylactic treatment target VGCCs, which probably contributes to their analgesic effect. This review aims to summarize the current evidence of VGGC contribution to migraine physiopathology and to discuss how current pharmacological options for migraine treatment interfere with VGGC function. PERSPECTIVE: Calcitonin gene-related peptide (CGRP) represents a major migraine mediator, but few studies have investigated the relationship between CGRP and VGCCs. CGRP release is calcium channel-dependent and VGGCs are key players in familial migraine. Further studies are needed to determine whether VGCCs are suitable molecular targets for treating migraine.

[CGRP: from neuropeptide to the therapeutic target (background and pathophysiology)]

Calcitonin gene-related peptide (CGRP) plays a pivotal role in migraine pathophysiology. The importance of CGRP in migraine became evident from numerous clinical studies investigating CGRP levels both interictally and ictally and reports on the efficacy of CGRP-based migraine therapies. In this paper, the above mentioned studies will be presented and the reader will be introduced to the development of CGRP-based medication. Finally, current study results on CGRP receptor antagonists, the so-called gepants, will be presented.

The preclinical discovery and development of atogepant for migraine prophylaxis

INTRODUCTION

Atogepant is a selective calcitonin gene-related peptide (CGRP) receptor antagonist that is utilized in adults for the prevention of episodic and chronic migraine. Cumulative findings support the involvement of CGRP in migraine pathophysiology, and atogepant functions by competitively antagonizing CGRP receptors, which results in the inhibition of trigeminovascular nociception. The mechanism of action addresses the cause of migraine pain, providing an effective preventive treatment option.

AREAS COVERED

The key milestones in its development, including preclinical achievements, phase I, II, and III clinical trials, and regulatory approvals are reviewed. Additionally, clinical efficacy, safety profile, and tolerability of atogepant are discussed. The literature review is based on a comprehensive search of English peer-reviewed articles from various electronic databases, including PubMed and ClinicalTrials.gov.

EXPERT OPINION

The development of atogepant represents a significant breakthrough in migraine prevention, particularly due to its improved safety profile that reduces the risk of liver injury, which was a major limitation of first-generation gepants. Drug-drug interaction studies with atogepant highlight the necessity for more inclusive study populations. Given that migraine disproportionately affects females, future clinical development programs should include diverse patient demographics to ensure the findings are generalizable to all individuals suffering from migraine.

An update on drug-drug interactions in older adults living with human immunodeficiency virus (HIV)

INTRODUCTION

People with HIV are living longer due to advances in antiretroviral therapy. With improved life expectancy comes an increased lifetime risk of comorbid conditions - such as cardiovascular disease and cancer - and polypharmacy. Older adults, particularly those living with HIV, are more vulnerable to drug interactions and adverse effects, resulting in negative health outcomes.

AREA COVERED

Antiretrovirals are involved in many potential drug interactions with medications used to treat common comorbidities and geriatric conditions in an aging population of people with HIV. We review the mechanisms and management of significant drug-drug interactions involving antiretroviral medications and non-antiretroviral medications commonly used among older people living with HIV. The management of these interactions may require dose adjustments, medication switches to alternatives, enhanced monitoring, and considerations of patient- and disease-specific factors.

EXPERT OPINION

Clinicians managing comorbid conditions among older people with HIV must be particularly vigilant to side effect profiles, drug-drug interactions, pill burden, and cost when optimizing treatment. To support healthier aging among people living with HIV, there is a growing need for antiretroviral stewardship, multidisciplinary care models, and advances that promote insight into the correlations between an individual, their conditions, and their medications.

Anti-calcitonin Gene-Related Peptide Monoclonal Antibodies in Migraine: Focus on Clinical Pharmacokinetics

The calcitonin gene-related peptide transmission was the target for recent development of drugs that effectively prevent attacks of both episodic and chronic migraine. The aim of this narrative review was to offer deeper insight into pharmacokinetics of monoclonal antibodies approved for prevention of migraine attacks. For this narrative review, relevant literature was searched for in MEDLINE and Google Scholar databases, covering periods 1966-2023 and 2006-2023, respectively. The ClinicalTrials.gov database was also searched for relevant clinical studies whose results had not been published previously in medical journals, covering the period 2000-2023. The monoclonal antibodies from this group are distributed mainly in the plasma and part of the extracellular space; they are neither metabolized in the liver nor excreted via the kidneys. The elimination of galcanezumab, eptinezumab and fremanezumab takes place only by a non-specific linear process via the reticuloendothelial system in the liver, while erenumab is eliminated by a non-specific process and by a specific, saturable process because of binding to receptors located on the cell membrane. Since the elimination processes do not have a large capacity, the half-life is about 2 weeks for erenumab and about 4 weeks for other monoclonal antibodies. Variability in the pharmacokinetics of these monoclonal antibodies is small in different subpopulations, and body weight is the only parameter to consider when choosing the dose of these drugs.

Impact of multiple treatment cycles with anti-CGRP monoclonal antibodies on migraine course: focus on discontinuation periods. Insights from the multicenter, prospective, I-GRAINE study

OBJECTIVES

While a single 12-month treatment cycle (TrC) with anti-CGRP mAbs is not disease-modifying for most patients, there is limited understanding of the effects of multiple TrCs on migraine course. We evaluated whether a second TrC might modify the migraine course by comparing the occurrence of migraine relapse after discontinuation of the second TrC to that following the cessation of the first TrC.

METHODS

In a real-life, multicenter, prospective study we considered all consecutive patients diagnosed with high-frequency episodic migraine (HFEM) or chronic migraine (CM) with > 3 treatment failures and treated with any anti-CGRP mAbs for ≥ 2 consecutive 12-month TrCs who were responders at week 12. The primary endpoint was the change in monthly migraine days (MMD) for HFEM or monthly headache days (MHD) for CM at the first month of treatment discontinuation after the second TrC (D2) compared to the first TrC (D1). Secondary endpoints included variations in monthly analgesic medications (MAM), Numeric Rating Scale (NRS), and Headache Impact Test (HIT-6) scores, ≥ 50%, ≥ 75%, and 100% response rates, and relapse from episodic migraine to CM and from no-medication overuse (MO) to MO at D2 vs. D1.

RESULTS

One-hundred-seventy-eight patients completed two 12-month TrCs with anti-CGRP mAbs. At D2, patients experienced a significant reduction in MMD (- 0.6, p = 0.028), MHD (- 2.6, p < 0.001), monthly analgesic medications (- 2.0, p < 0.001), and HIT-6 score (- 2.2, p < 0.001) compared to D1, indicating improved effectiveness. The ≥ 50% response rate at weeks 45-48 during the first TrC was 95.5%, while at weeks 45-48 of the second TrC was 99.4%. Corresponding rates at D1 was 20.2% whereas at D2 was 51.6% (p < 0.0001). No statistical difference emerged in ≥ 75% and 100% responders. The relapse rate from episodic migraine to CM at D2 was lower than at D1 (12.3% vs 30.4%; p = 0.0002) Fewer patients experienced relapse from no-MO to MO at D2 compared to D1 (29.5% vs 68.7%; p = 0.00001).

DISCUSSION

A second TrC with anti-CGRP mAbs demonstrated clinical improvements compared to the first one, as indicated by a milder migraine relapse at D2 compared to D1. Multiple TrCs with anti-CGRP mAbs could progressively modify migraine evolution by reducing CGRP-dependent neuroinflammatory nociceptive inputs to the brain.

Acute Treatment of Migraine: Expert Consensus Statements from the United Arab Emirates (UAE)

INTRODUCTION

Migraine, characterized by recurrent headaches and often accompanied by other symptoms like nausea, vomiting, and sensitivity to light and sound, significantly impacts patients' quality of life (QoL) and daily functioning. The global burden of migraines is reflected not only in terms of reduced QoL but also in the form of increased healthcare costs and missed work or school days. While UAE (United Arab Emirates)-specific consensus-based recommendations for the effective use of preventive calcitonin gene-related peptide (CGRP)-based migraine therapies have been published previously, an absence of such regional guidance on the management of acute migraine represents a gap that needs to be urgently addressed.

METHODS

A task force of eight neurologists from the UAE with expertise in migraine management conducted a comprehensive literature search and developed a set of expert statements on the management of acute migraine that were specific to the UAE context. To ensure diverse perspectives are considered, a Delphi panel comprising 16 neurologists plus the task force members was set up. Consensus was achieved using a modified Delphi survey method. Consensus was predefined as a median rating of 7 or higher without discordance (if > 25% of the Delphi panelists rate an expert statement as 3 or lower on the Likert scale). Expert statements achieving consensus were adopted.

RESULTS

The Modified Delphi method was used successfully to achieve consensus on all nine expert statements drafted by the task force. These consensus statements aim to provide a comprehensive guide for UAE healthcare professionals in treating acute migraine. The statements cover all aspects of acute migraine treatment, including what goals to set, the timing of treatment, treatment strategy to use in case of inadequate response to triptans, safety aspects of combining gepants for acute attacks with preventive CGRP-based therapies, special population (pregnant and pediatric patients) considerations, and the management of the most bothersome symptoms (MBS).

CONCLUSIONS

Adopting these consensus statements on the treatment of acute migraine can help enhance patient care, improve outcomes, and standardize treatment practices in the UAE. The collaborative effort of experts with diverse experiences in developing these consensus statements will strengthen the credibility and applicability of these statements to various healthcare settings in the country.

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.

Real-world experience with calcitonin gene-related peptide-targeted antibodies for migraine prevention: a retrospective observational cohort study at two Japanese headache centers

BACKGROUND

Although randomized controlled trials (RCTs) have shown that calcitonin gene-related peptide (CGRP)-targeted monoclonal antibodies (CGRP mAbs) are an efficacious and safe therapeutic modality for migraine prevention, their clinical benefits have not been well validated in Japanese patients in the real-world setting. The present study aimed to evaluate the real-world efficacy and safety of galcanezumab, fremanezumab, and erenumab in Japanese patients with migraine.

METHODS

This observational retrospective cohort study was conducted at two headache centers in Japan. Patients with migraine who had experienced treatment failure with at least one traditional oral migraine preventive agent were treated with a CGRP mAb de novo. The primary efficacy endpoints were the changes from baseline in monthly migraine days (MMDs) and Headache Impact Test-6 (HIT-6) score after 3 dosing intervals (V3). We explored whether demographic and clinical characteristics predicted therapeutic outcomes at V3.

RESULTS

Sixty-eight patients who completed three doses of a CGRP mAb (85.3% female [58/68], mean age: 46.2 ± 13.1 years) were included in the analysis. There were 19 patients with chronic migraine. The baseline MMDs were 13.4 ± 6.0. After 3 doses, the MMDs significantly decreased to 7.4 ± 5.5 (p < 0.0001), and the 50% response rate was 50.0%. HIT-6 score was significantly reduced from 66.7 ± 5.4 to 56.2 ± 8.7 after 3 doses (P = 0.0001). There was a positive correlation between the changes in MMDs and HIT-6 score from baseline after 2 doses (p = 0.0189). Those who achieved a ≥ 50% therapeutic response after the first and second doses were significantly more likely to do so at V3 (crude odds ratio: 3.474 [95% CI: 1.037 to 10.4], p = 0.0467). The most frequent adverse event was constipation (7.4%). None of the adverse events were serious, and there was no need for treatment discontinuation.

CONCLUSIONS

This real-world study demonstrated that CGRP mAbs conferred Japanese patients with efficacious and safe migraine prevention, and an initial positive therapeutic response was predictive of subsequent favorable outcomes. Concomitant measurement of MMDs and HIT-6 score was useful in evaluating the efficacy of CGRP mAbs in migraine prevention.

Monoclonal Antibody Targeting CGRP Relieves Cisplatin-Induced Neuropathic Pain by Attenuating Neuroinflammation

Chemotherapy-induced neuropathic pain (CIPN) is a common side effect of antitumor chemotherapeutic agents. It describes a pathological state of pain related to the cumulative dosage of the drug, significantly limiting the efficacy of antitumor treatment. Sofas strategies alleviating CIPN still lack. Calcitonin gene-related peptide (CGRP) is a neuropeptide involved in many pathologic pains. In this study, we explored the effects of CGRP blocking on CIPN and potential mechanisms. Total dose of 20.7 mg/kg cisplatin was used to establish a CIPN mouse model. Mechanical and thermal hypersensitivity was measured using von Frey hairs and tail flick test. Western blot and immunofluorescence were utilized to evaluate the levels of CGRP and activated astrocytes in mouse spinal cord, respectively. In addition, real-time quantitative PCR (RT-qPCR) was used to detect the level of inflammatory cytokines such as IL-6, IL-1β, and NLRP3 in vitro and in vivo. There are markedly increased CGRP expression and astrocyte activation in the spinal cord of mice following cisplatin treatment. Pretreatment with a monoclonal antibody targeting CGRP (ZR8 mAb) effectively reduced cisplatin-induced mechanical hypersensitivity and thermal nociceptive sensitization and attenuated neuroinflammation as marked by downregulated expression of IL-6, IL-1β, and NLRP3 in the mice spinal cord and spleen. Lastly, ZR8 mAb does not interfere with the antitumor effects of cisplatin in tumor-bearing mice. Our findings indicate that neutralizing CGRP with monoclonal antibody could effectively alleviate CIPN by attenuating neuroinflammation. CGRP is a promising therapeutic target for CIPN.