Response Predictors in Chronic Migraine: Medication Overuse and Depressive Symptoms Negatively Impact Onabotulinumtoxin-A Treatment

Improvement of comorbid anxiety and depression in patients with migraine treated with injectable preventive calcitonin gene-related peptide antagonists: Review of clinical evidence

Background

Migraine is often associated with depression and anxiety, leading to a diminished quality of life. Calcitonin gene-related peptide (CGRP) antagonists have shown promise in treating migraines, but their effects on concurrent depression and anxiety have not been clarified.

Methods

A literature review was conducted on ClinicalTrials.gov, PubMed, Ovid Medline, and EMBASE focusing on phase 3 clinical trials, post-hoc analysis studies, and real-world evidence (RWE) published in the past 5 years. The review primarily utilized patient-reported outcome tools, such as the Patient Health Questionnaire-9, Hamilton Depression Rating Scale, Beck Depression Inventory-II, generalized anxiety disorder (GAD)-7, and Hamilton Anxiety Rating Scale (HARS), to assess anxiety and depression in relation to CGRP-targeted monoclonal antibodies.

Results

Out of 260 studies, 17 met the inclusion criteria. Eptinezumab lacked sufficient evidence regarding its impact on depression and anxiety. While sufficient evidence on its effect on comorbid anxiety was not available, fremanezumab was shown to significantly improve comorbid depression in one study while not achieving statistical significance in another. Erenumab and galcanezumab showed significant improvement in comorbid depression, implying possible benefits in patients with migraine. Galcanezumab showed faster relief from depressive symptoms than other injectable CGRP antagonists. Galcanezumab also exhibited improvements in GAD-7 scores for anxiety, although not statistically significant, whereas RWE showed promising HARS scores for both galcanezumab and erenumab.

Conclusions

Galcanezumab and erenumab appear to be more effective in improving concurrent depressive and anxiety symptoms in migraine patients than fremanezumab. Notably, these psychometric questionnaires were not the primary outcome measures of the trials and were not specifically designed to investigate the effects of these medications on depression or anxiety. Further research is needed to fully understand the impact of CGRP antagonists on mental health disorders associated with migraines. These findings have implications for enhancing the overall well-being and quality of life in individuals with migraines and comorbid psychiatric conditions.

Depression and treatment with anti-calcitonin gene related peptide (CGRP) (ligand or receptor) antibodies for migraine

BACKGROUND AND PURPOSE

The aim was to evaluate the effect of anti-calcitonin gene related peptide (CGRP) (ligand or receptor) antibodies on depressive symptoms in subjects with migraine and to determine whether depressive symptoms predict treatment response.

METHODS

Patients with migraine treated with erenumab and fremanezumab at the Leiden Headache Centre completed daily E-headache diaries. A control group was included. Depressive symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS) and the Center for Epidemiological Studies Depression Scale (CES-D) questionnaires at baseline (T0) and after 3 months (T1). First, the effect of treatment on the reduction in HADS-D and CES-D scores was assessed, with reduction in depression scores as the dependent variable and reduction in monthly migraine days (MMD) and treatment with anti-CGRP medication as independent variables. Second, depression as a predictor of treatment response was investigated, using the absolute reduction in MMD as a dependent variable and age, gender, MMD, active depression, impact, stress and locus of control scores as independent variables.

RESULTS

In total, n = 108 patients were treated with erenumab, n = 90 with fremanezumab and n = 68 were without active treatment. Treatment with anti-CGRP medication was positively associated with a reduction in the HADS-D (β = 1.65, p = 0.01) compared to control, independent of MMD reduction. However, the same effect was not found for the CES-D (β = 2.15, p = 0.21). Active depression predicted poorer response to erenumab (p = 0.02) but not to fremanezumab (p = 0.09).

CONCLUSION

Anti-CGRP (ligand or receptor) monoclonals lead to improvement of depressive symptoms in individuals with migraine, independent of migraine reduction. Depression may predict treatment response to erenumab but not to fremanezumab.

Breaking the cycle: unraveling the diagnostic, pathophysiological and treatment challenges of refractory migraine

Background

Refractory migraine is a poorly described complication of migraine in which migraine has chronified and become resistant to standard treatments. The true prevalence is unknown, but medication resistance is common in headache clinic patient populations. Given the lack of response to treatment, this patient population is extremely difficult to treat with limited guidance in the literature.

Objective

To review the diagnostic, pathophysiological, and management challenges in the refractory migraine population.

Discussion

There are no accepted, or even ICHD-3 appendix, diagnostic criteria for refractory migraine though several proposed criteria exist. Current proposed criteria often have low bars for refractoriness while also not meeting the needs of pediatrics, lower socioeconomic status, and developing nations. Pathophysiology is unknown but can be hypothesized as a persistent "on" state as a progression from chronic migraine with increasing central sensitization, but there may be heterogeneity in the underlying pathophysiology. No guidelines exist for treatment of refractory migraine; once all guideline-based treatments are tried, treatment consists of n-of-1 treatment trials paired with non-pharmacologic management.

Conclusion

Refractory migraine is poorly described diagnostically, its pathophysiology can only be guessed at by extension of chronic migraine, and treatment is more the art than science of medicine. Navigating care of this refractory population will require multidisciplinary care models and an emphasis on future research to answer these unknowns.

Neurological and psychiatric comorbidities of migraine: Concepts and future perspectives

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Searching for the Predictors of Response to BoNT-A in Migraine Using Machine Learning Approaches

OnabotulinumtoxinA (BonT-A) reduces migraine frequency in a considerable portion of patients with migraine. So far, predictive characteristics of response are lacking. Here, we applied machine learning (ML) algorithms to identify clinical characteristics able to predict treatment response. We collected demographic and clinical data of patients with chronic migraine (CM) or high-frequency episodic migraine (HFEM) treated with BoNT-A at our clinic in the last 5 years. Patients received BoNT-A according to the PREEMPT (Phase III Research Evaluating Migraine Prophylaxis Therapy) paradigm and were classified according to the monthly migraine days reduction in the 12 weeks after the fourth BoNT-A cycle, as compared to baseline. Data were used as input features to run ML algorithms. Of the 212 patients enrolled, 35 qualified as excellent responders to BoNT-A administration and 38 as nonresponders. None of the anamnestic characteristics were able to discriminate responders from nonresponders in the CM group. Nevertheless, a pattern of four features (age at onset of migraine, opioid use, anxiety subscore at the hospital anxiety and depression scale (HADS-a) and Migraine Disability Assessment (MIDAS) score correctly predicted response in HFEM. Our findings suggest that routine anamnestic features acquired in real-life settings cannot accurately predict BoNT-A response in migraine and call for a more complex modality of patient profiling.

A Retrospective Real-Life Multicenter Study on Concurrent Oral Preventive Treatments in Patients with Chronic Migraine Treated with OnabotulinumtoxinA

BACKGROUND AND OBJECTIVE

OnabotulinumtoxinA (BoNTA) is a relatively safe and effective treatment for chronic migraine. The local mode of action of BoNTA favors the combination of oral treatments with systemic action. However, little is known about the possible interactions with other preventive treatments. The objective of the study was to describe the use of oral preventive treatments in patients with chronic migraine treated with BoNTA in routine clinical care and discuss the tolerability and efficacy according to the presence or absence of concomitant oral treatments.

METHODS

In this multicenter, observational, retrospective, cohort study, we collected data from patients with chronic migraine receiving prophylactic treatment with BoNTA. Patients were eligible if aged ≥18 years, diagnosed with chronic migraine according to the International Classification of Headache Disorders, Third Edition criteria, and treated with BoNTA according to the PREEMPT paradigm. We documented the proportion of patients with at least one concomitant treatment prescribed specifically for migraine (CT+M) and their side effects during four BoNTA treatment cycles. Additionally, we collected monthly headache days and monthly acute medication days from the patients' headache diaries. Patients with CT+M were compared to those without concomitant treatment (CT-) using a nonparametric approach.

RESULTS

Our cohort included 181 patients taking BoNTA, of whom 77 (42.5%) received a CT+M. The most frequently prescribed concomitant treatments were antidepressants and antihypertensive drugs. Side effects in the CT+M group occurred in 14 patients (18.2%). Only in three of them (3.9%), the side effects had a significant interference with the patient's functioning (all in topiramate 200-mg/day users). Both CT+M and CT- groups had a significant reduction in monthly headache days of respectively - 6 (95% confidence interval - 9, - 3; p < 0.001; w = 0.200) during cycle 4 compared with baseline versus - 9 (95% confidence interval - 13, -6; p < 0.001; w = 0.469). However, the reduction in monthly headache days was significantly smaller in patients with CT+M after the fourth treatment cycle compared with patients with CT- (p = 0.004).

CONCLUSIONS

Prescription of oral concomitant preventive treatment is common in patients with chronic migraine receiving BoNTA. We did not identify any unexpected safety or tolerability issues in patients receiving BoNTA and a CT+M. However, patients with a CT+M experienced a smaller reduction in monthly headache days when compared with those with CT-, which might be associated with a higher resistance to treatment in that subgroup of patients.

Safety of Onabotulinumtoxin A in Chronic Migraine: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Some 14% of global prevalence, based on high-income country populations, suffers from migraine. Chronic migraine is very disabling, being characterized by at least 15 headache days per month of which at least 8 days present the features of migraine. Onabotulinumtoxin A, targeting the machinery for exocytosis of neurotransmitters and neuropeptides, has been approved for use in chronic migraine since 2010. This systematic review and meta-analysis appraises the safety of onabotulinumtoxin A treatment for chronic migraine and the occurrence of treatment-related adverse events (TRAEs) in randomized, clinical studies in comparison with placebo or other comparators and preventative treatments according to the most updated Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 recommendations. The search retrieved 888 total records. Nine studies are included and seven were eligible for meta-analysis. The present study demonstrates that toxin produces more TRAEs than placebo, but less than oral topiramate, supporting the safety of onabotulinumtoxin A, and highlights the heterogeneity of the studies present in the literature (I² = 96%; p < 0.00001). This points to the need for further, adequately powered, randomized clinical trials assessing the safety of onabotulinumtoxin A in combination with the newest treatment options.

Efficacy and safety of two different botulinum toxin type A dilutions in chronic migraineurs

Botulinum toxin type A is an effective preventive therapy for chronic migraine. Although the guidelines suggest a 50U/ml dilution of OnabotulinumtoxinA (BoNT/A), many clinicians use more concentrated solutions. However, there are no studies regarding the effect and safety of 100U/ml BoNT/A dilution with the saline solution following the PREEMPT paradigm. Our primary goal was to evaluate the efficacy, in reducing migraine frequency, and safety of two different BoNT/A dilutions (100U/ml vs 50U/ml) in the treatment of Chronic migraine. Our secondary goal was to determine the predictors of BoNT/A response. We retrospectively collected data from 113 chronic migraine patients treated with 3 rounds of BoNT/A according to the PREEMPT protocol as a preventive therapy. Patients were divided into two groups, based on BoNT/A dilution: 50U/ml (49 patients) vs. 100U/ml (64 patients) of sodium chloride 0.9%. We compared the migraine days/month, intensity, and intake of symptomatic medications at the baseline with the data obtained after the treatment; moreover, we evaluated the occurrence of adverse effects observed in the two groups. There was no difference regarding efficacy and safety between the two groups except for eyelid ptosis, which was more common in the 50U/ml BoNT/A group (p 0.018). Unilateral localization of migraine was associated with a more favorable outcome (OR 5.593, C.I. 2.358-13.268; p < 0.001) while Major Depressive Disorder predicted a less favorable response (OR 0.213, C.I. 0.087-0.523; p < 0.001). In our study, BoNT/A dilution did not influence the response to the therapy, but 100U/ml dilution could reduce the risk of eyelid ptosis. Unilateral localization of migraine pain might predict a more favorable response to the therapy, while the presence of a Major Depressive Disorder might predict a less favorable response.

Clinical evaluation of super-responders vs. non-responders to CGRP(-receptor) monoclonal antibodies: a real-world experience

BACKGROUND

Clinical trials and real-world studies revealed a spectrum of response to CGRP(-receptor) monoclonal antibodies (mAbs) in migraine prophylaxis, ranging from no effect at all to total migraine freedom. In this study, we aimed to compare clinical characteristics between super-responders (SR) and non-responders (NR) to CGRP(-receptor) mAbs.

METHODS

We performed a retrospective cohort study at the Headache Center, Charité - Universitätsmedizin Berlin. The definition of super-response was a ≥ 75% reduction in monthly headache days (MHD) in the third month after treatment initiation compared to the month prior to treatment begin (baseline). Non-response was defined as ≤ 25% reduction in MHD after three months of treatment with a CGRP-receptor mAb and subsequent three months of treatment with CGRP mAb, or vice versa. We collected demographic data, migraine disease characteristics, migraine symptoms during the attacks in both study groups (SR/NR) as well as the general medical history. SR and NR were compared using Chi-square test for categorical variables, and t-test for continuous variables.

RESULTS

Between November 2018 and June 2022, n = 260 patients with migraine received preventive treatment with CGRP(-receptor) mAbs and provided complete headache documentation for the baseline phase and the third treatment month. Among those, we identified n = 29 SR (11%) and n = 26 NR (10%). SR reported more often especially vomiting (SR n = 12/25, 48% vs. NR n = 4/22, 18%; p = 0.031) and typical migraine characteristics such as unilateral localization, pulsating character, photophobia and nausea. A subjective good response to triptans was significantly higher in SR (n = 26/29, 90%) than in NR (n = 15/25, 60%, p = 0.010). NR suffered more frequently from chronic migraine (NR n = 24/26, 92% vs. SR n = 15/29, 52%; p = 0.001), medication overuse headache (NR n = 14/24, 58% versus SR n = 8/29, 28%; p = 0.024), and concomitant depression (NR n = 17/26, 65% vs. SR n = 8/29, 28%; p = 0.005).

CONCLUSION

Several clinical parameters differ between SR and NR to prophylactic CGRP(-R) mAbs. A thorough clinical evaluation prior to treatment initiation might help to achieve a more personalized management in patients with migraine.

Effectiveness and Safety of Chronic Migraine Preventive Treatments: A Systematic Literature Review

INTRODUCTION

Numerous medications are used for the preventive treatment of chronic migraine (CM), including oral treatments, onabotulinumtoxinA (onabotA; BOTOX), and calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs). Despite substantial clinical trial evidence, less is published about the real-world experience of these treatments based on data routinely collected from a variety of sources. This systematic review assessed real-world evidence on the effectiveness and safety of preventive treatments for CM in adults.

METHODS

A systematic search of MEDLINE, Embase, and the Cochrane library with back-referencing and supplementary searches retrieved data published between January 2010 and February 2020. Publications were screened, extracted, and quality assessed. Data were narratively synthesized. Search criteria included preventive medications for CM. Evidence was available for topiramate, onabotulinumtoxinA, CGRP mAbs (erenumab, galcanezumab, and fremanezumab). OnabotulinumtoxinA was most commonly assessed (55 studies), followed by erenumab (six studies), multiple CGRP mAbs (one study), and topiramate (one study). Long-term data (> 1 year) were available for onabotulinumtoxinA only, with erenumab reported up 6 months, topiramate up to 3 months, and multiple CGRP mAbs up to 12 months.

RESULTS

Substantial data demonstrated that onabotulinumtoxinA reduces the number/frequency of headaches, concomitant acute medication use, and impact of headaches on well-being and daily activity. More limited evidence showed benefits for the same parameters with erenumab. Single studies suggested topiramate and multiple CGRP mAbs decrease the number/frequency of headaches and impact of headaches. To date, onabotulinumtoxinA is the only preventive treatment for CM that has long-term safety data in real-world settings reporting treatment-related adverse events of up to 3 years.

CONCLUSION

While substantial real-world evidence supports the long-term effectiveness and safety of onabotulinumtoxinA, real-world data on other preventive treatments of CM are currently limited to short term effectiveness due to their more recent approvals.

Effectiveness of anti-CGRP monoclonal antibodies in the preventive treatment of migraine: A prospective study of 63 patients

INTRODUCTION

Calcitonine Gen-Related Peptide (CGRP) established a revolution in migraine pathophysiology knowledge and has led to the development of new drugs specifically targeting this disease.

METHODS

We present a prospective study in which 63 episodic and chronic migraine patients have been treated with anti-CGRP monoclonal antibodies describing their efficacy, security and relapses after their interruption. Response predictors have been analyzed such they can help us to create a better treatment plan.

RESULTS

Average age was 48.3 ± 11.81 years old, 84.1% of them being women. The average was of 15.59 migraine days per month (MDM). 63.5% of all patients suffered chronic migraine. The initial dose of Erenumab in all patient was 70 mg subcutaneous. This was increased to 140 mg in 47.6% of the patients. An MDM reduction between 49.85% and 59.53% was obtained within three to twelve months from the start of treatment. Constipation was present in 17.5% of the patients and 4.8% suffered injection site reaction. The treatment was changed to Galcanezumab in 17.9% of the patients. After interrupting the treatment, 23 patients relapsed with a good response on reintroduction of the treatment. It was not possible to establish a clear response predictor, however a statistically significant increase in the number of days of improvement was observed with more MDM at baseline level (p = 0.002).

CONCLUSIONS

Anti-CGRP monoclonal antibodies are effective, safe, and well tolerated drugs. We have observed that their discontinuation, in some cases can lead to frequent and early relapses so we strongly recommend to extend the treatment in those patients with a higher MDM.

Real-World Evaluation of the Tolerability to Onabotulinum Toxin A: The RETO Study

Onabotulinumtoxin A (onabotA) has shown efficacy in chronic migraine (CM), with good tolerability and a low rate of adverse effects, most of them not severe. The aim of this study is to evaluate tolerability and adverse effects of onabotA in clinical practice and to analyze if there is a relationship between tolerability to treatment administration, adverse effects' (AEs) occurrence and clinical response. We included patients with CM that received treatment with onabotA for the first time. Tolerability to treatment was evaluated by a 0-10 numeric rating scale (0: worst possible, 10: optimal tolerability). We assessed the presence of AEs by using a standardized questionnaire. Treatment response was based on the 50 and 75% responder rate between weeks 20 and 24, compared with the baseline, according to headache diaries. We analyzed whether the tolerability was associated with a higher frequency of AEs or a higher probability of clinical response. We included 105 patients, 87.7% female, with an age of 43.9 ± 10.7 years. Mean tolerability was 7.8/10 and 7.2/10 in the first and second onabotA administration, respectively. AEs were reported by (first-second) 71.4-68.6% patients. The percentage of patients with a 50% response was 56.3%. There was no association between tolerability and AEs' occurrence or clinical response.

Effectiveness of onabotulinumtoxinA (BOTOX®) for the preventive treatment of chronic migraine: A meta-analysis on 10 years of real-world data

BACKGROUND

This meta-analysis evaluated the real-world effectiveness of onabotulinumtoxinA (BOTOX®), the first preventive treatment FDA-approved specifically for chronic migraine in 2010.

METHODS

We systematically reviewed onabotulinumtoxinA observational data in chronic migraine published between 1 January 2010 and 31 March 2021. Random-effects models evaluated available data for primary and secondary endpoints defined in onabotulinumtoxinA pivotal trials at approximately 24 weeks and 52 weeks.

RESULTS

Of the 44 full-text eligible studies (29 prospective; 13 retrospective; 2 other), seven evaluated change from baseline (mean[confidence interval]) at ∼24 weeks and ∼52 weeks, respectively, for onabotulinumtoxinA in: number of headache days/month: (-10.64 [-12.31, -8.97]; -10.32 [-14.92, -5.73]); number of days of acute headache pain medication intake per month (-7.40 [-13.04, -1.77]; overlapping CIs at 52 weeks); total Headache Impact Test-6 score (-11.70 [-13.86, -9.54]); -11.80 [14.70, -8.90]); and Migraine-Specific Quality-of-Life v2.1 score (MSQ; 23.60 [CI: 21.56, 25.64]; 30.90 [CI: 28.29, 33.51]). At ∼24 weeks onabotulinumtoxinA showed total Migraine Disability Assessment score of 44.74 [28.50, 60.99] and ≥50% reduction in migraine days response rate of 46.57% [29.50%, 63.65%]. A sensitivity analysis at study-end suggested durability of onabotulinumtoxinA effectiveness on MSQ.

CONCLUSION

The meta-analysis reflecting real-world practice broadly corroborated with evidence from pivotal and long-term open-label studies of onabotulinumtoxinA in chronic migraine preventive treatment.

Prediction and associated factors of non-steroidal anti-inflammatory drugs efficacy in migraine treatment

Background: The selection strategy of non-steroidal anti-inflammatory drugs (NSAIDs) for migraine is hard to judge whether it is effective, leading to unnecessary exposure to insufficient or lengthy treatment trials. The goal of the study was to investigate potential predictors of NSAIDs efficacy in migraine therapy and to explore their influence on efficacy. Methods: 610 migraine patients were recruited and assigned into responders and non-responders. Potential predictors among demographic and clinical characteristics for NSAIDs efficacy were extracted using multivariable logistic regression (LR) analysis, and were applied to construct prediction models via machine learning (ML) algorithms. Finally, Cochran-Mantel-Haenszel tests were used to examine the impact of each predictor on drug efficacy. Results: Multivariate LR analysis revealed migraine-related (disease duration, headache intensity and frequency) and psychiatric (anxiety, depression and sleep disorder) characteristics were predictive of NSAIDs efficacy. The accuracies of ML models using support vector machine, decision tree and multilayer perceptron were 0.712, 0.741, and 0.715, respectively. Cochran-Mantel-Haenszel test showed that, for variables with homogeneity of odds ratio, disease duration, frequency, anxiety, and depression and sleep disorder were associated with decreased likelihood of response to all NSAIDs. However, the variabilities in the efficacy of acetaminophen and celecoxib between patients with mild and severe headache intensity were not confirmed. Conclusion: Migraine-related and psychiatric parameters play a critical role in predicting the outcomes of acute migraine treatment. These models based on predictors could optimize drug selection and improve benefits from the start of treatment.

Is prednisone still a reasonable option in the treatment of withdrawal headache in patients with chronic migraine and medication overuse headache in the age of CGRP antibodies? A narrative review

OBJECTIVE

Along with the development of novel migraine therapies as the monoclonal antibodies against calcitonin gene-related peptide (CGRP) and its receptor, the question arises if the treatment of chronic migraine (CM) and medication overuse headache (MOH) must be reconsidered. Have previous therapeutic approaches, including glucocorticoids, lost their role in the management of this debilitating disorder? In this narrative review, we present an overview of the available treatment options in CM and MOH in light of CGRP antibodies as well as an evaluation of the role of glucocorticoids in withdrawal therapy.

BACKGROUND

Chronic migraine and medication overuse continues to be a difficult to treat condition. To date, potent treatment options are scarce and algorithms for advising patients with MOH are often still based on expert consensus rather than evidence-based medicine. For years and probably due to lack of effective alternatives, glucocorticoids have been used in MOH, especially to alleviate withdrawal symptoms caused by detoxification. Small case series report positive effects of steroids in this respective patient group; however, randomized controlled trials did not show a consistent benefit, although this may be due to methodological limitations. Because of these discrepancies, their role in MOH has been under debate ever since.

METHODS

We searched the electronic database PubMed for articles up to June 1, 2022 on the use of glucocorticoids in CM and MOH.

CONCLUSION

Despite popular use in clinical practice, there is currently still no scientific evidence for the efficacy of glucocorticoids in patients with CM and MOH. Treatment with monoclonal antibodies achieved high transition rates from medication overuse to non-overuse. However, further research is needed to evaluate the additional benefit of these new agents.

Excellent Response to OnabotulinumtoxinA: Different Definitions, Different Predictors

The identification of patients who can benefit the most from the available preventive treatments is important in chronic migraine. We explored the rate of excellent responders to onabotulinumtoxinA in a multicenter European study and explored the predictors of such response, according to different definitions. A pooled analysis on chronic migraineurs treated with onabotulinumtoxinA and followed-up for, at least, 9 months was performed. Excellent responders were defined either as patients with a ≥75% decrease in monthly headache days (percent-based excellent responders) or as patients with <4 monthly headache days (frequency-based excellent responders). The characteristics of excellent responders at the baseline were compared with the ones of patients with a <30% decrease in monthly headache days. Percent-based excellent responders represented about 10% of the sample, whilst frequency-based excellent responders were about 5% of the sample. Compared with non-responders, percent-based excellent responders had a higher prevalence of medication overuse and a higher excellent response rate even after the 1st and the 2nd injection. Females were less like to be frequency-based excellent responders. Chronic migraine sufferers without medication overuse and of female sex may find fewer benefits with onabotulinumtoxinA. Additionally, the excellent response status is identifiable after the first cycle.

Is There a Gender Difference in the Response to onabotulinumtoxinA in Chronic Migraine? Insights from a Real-Life European Multicenter Study on 2879 Patients

INTRODUCTION

Migraine is mostly a female disorder because of its lower prevalence in men. Less than 20% of patients included in the available studies on migraine treatments are men; hence, the evidence on migraine treatments might not apply to men. The aims of the present study were to provide reliable information on the effectiveness of onabotulinumtoxinA (BT-A) for chronic migraine in men and to compare clinical benefits between men and women.

METHODS

We performed a pooled patient-level gender-specific analysis of real-life data on BT-A for chronic migraine of patients followed-up to 9 months. We reported the 50% responder rates during each BT-A cycle, defined as percentage of reduction in monthly headache days (MHDs) compared to baseline, along with 75% and 30% responder rates. We also reported the mean decrease in MHDs and in days of acute medication use (DAMs) during each BT-A cycle as compared to baseline. We also evaluated the reasons for stopping the treatment within the third cycle.

RESULTS

We included an overall cohort of 2879 patients, 522 of whom (18.1%) were men. In men, 50% responder rates were 27.7% during the first BT-A cycle, 29.2% during the second, and 35.6% during the third cycle; in women, the corresponding rates were 26.6%, 33.5%, and 41.0%. In the overall cohort, responder rates did not differ between men and women during the first two cycles; during the third cycle, the distribution was different (P < 0.001) mostly because of higher rates of treatment stopping and non-responders in men. In the propensity score matched cohort, the trend was maintained but lost its statistical significance. Both men and women had a significant decrease in MHDs and in DAMs with BT-A treatment (P < 0.001). There were no gender differences in those changes with the only exception of MHD decrease which, during the third cycle, was lower in men than in women (7.4 vs 8.2 days, P = 0.016 in the overall cohort and 9.1 vs 12.5 days, P = 0.009 in the propensity score matched cohort). At the end of follow-up, 152 men and 485 women stopped BT-A treatment (29.1% vs 20.6%; P < 0.001). The relative proportion of patients stopping treatment because of inadequate response (less than 30% decrease in MHDs from baseline) was higher in men than in women (42.8% vs 39.6%), while the proportion of patients stopping because of adverse events was higher in women than in men (5.6% vs 0%; P = 0.031).

CONCLUSIONS

Our pooled analysis suggests that the response to BT-A is significant in both men and women with a small gender difference in favor of women. Men tended to stop the treatment more frequently than women. We emphasize the need for more gender-specific data on migraine treatments from randomized controlled trials and observational studies.

Refractory migraine profile in CGRP-monoclonal antibodies scenario

Objective

Refractory migraine (Ref‐M) represents a conundrum that headache experts have to face with. We aim to investigate whether a peculiar profile may characterize patients with Ref‐M according to 2020 European Headache Federation criteria. Furthermore, to substantiate a dysfunctional dopaminergic pathway involvement in these patients, we explored the effectiveness of olanzapine.

Materials & Methods

Eighty‐four patients (fitting previous Ref‐M criteria of the 2014) were treated with erenumab for six months. Differences between clinical and demographic features of responder (Ref‐M according to 2014 criteria) and not‐responder (Ref‐M according to 2020 criteria) patients to CGRP‐mAbs were investigated and their predictive values assessed. In fifteen patients with Ref‐M not responders to CGRP‐mAbs, olanzapine was administered (5 mg/die) for 3 months and frequency and pain intensity of migraine attacks were estimated.

Results

Patients with Ref‐M not responsive to CGRP‐mAbs (29/84) when compared with Ref‐M responsive to CGRP‐mAbs showed higher baseline frequency of migraine attacks, medication overuse and pain catastrophizing scale (PCS) scores. Logistic regression analyses showed that frequency of attacks, medication overuse and PCS score represent independent negative predictors of CGRP‐mAbs response. A ≥50% reduction of headache days/month was observed after olanzapine treatment in 67% of patients with Ref‐M not responsive to CGRP‐mAbs.

Conclusions

We outline that higher frequency of migraine attacks, medication overuse and pain catastrophizing characterize patients with Ref‐M not responsive to CGRP‐mAbs. In this frame, olanzapine effectiveness on frequency and pain intensity of migraine attacks supports the hypothesis that migraine refractoriness may be subtended by a prominent involvement of the dopaminergic pathway.

Predictors of response to erenumab after 12 months of treatment

OBJECTIVE

Erenumab is a monoclonal antibody acting against calcitonin gene-related peptide receptor and approved for the preventive treatment of chronic migraine. The aim of the present study is to identify clinical predictors of good response in patients with chronic migraine and medication overuse-headache.

MATERIAL AND METHODS

This was a retrospective single-center not funded study. Enrolled patients were affected by chronic migraine and medication overuse-headache treated with erenumab monthly, up to 1 year. At 1 year, patients were classified as good responders if they displayed a ≥50% reduction in the number of headache days per months compared to the baseline.

RESULTS

After 1 year, a significant improvement in the number of headache days per months, analgesic consumption, 6-items headache impact test, and migraine disability assessment questionnaire scores were obtained compared to the baseline. Patients who obtained a ≥50% reduction in the number of headache days per month compared to the baseline displayed a longer history of medication overuse-headache, a higher number of painkillers taken per month at the baseline and a higher number of failed preventive treatments in the past.

CONCLUSIONS

Patients with longer medication overuse-headache duration, higher analgesic intake, and a higher number of previous preventive treatment failures may receive less benefit with erenumab.

Identification of predictors of response to Erenumab in a cohort of patients with migraine

Background:

The migraine-specific monoclonal antibody Erenumab targeting the calcitonin gene related peptide receptor is an effective and well tolerated preventive treatment of episodic and chronic migraine. However, its price limits its use as a first line therapy against migraine. Therefore, identifying patients who will adequately respond to such treatment is paramount.

Methods:

In this retrospective, real-life cohort study, 172 adult patients with refractory episodic or chronic migraine treated with Erenumab were included. To identify the predictors of response to Erenumab, bivariate subgroup analysis of several potential factors was performed, and multivariate logistic regression modeling was done to obtain Odds Ratio (OR).

Results:

Of the 172 patients, 57.0% achieved a successful treatment response (reduction of monthly migraine days by ≥50%). Statistically significant predictors of a treatment response were the presence of chronic migraine, tension-type headache, and a positive response to triptan with an odd ratio of 0.473 (95% CI, 0.235–0.952), 0.485 (95% CI, 0.245–0.962) and 3.985 (95% CI, 1.811–8.770), respectively (P < 0.05).

Conclusions:

Successful Erenumab treatment response rate was 57.0% in this retrospective cohort. As chronic migraine and tension-type headache were negative predictors of Erenumab response while triptan response was a positive predictor, this data suggests the potential for Erenumab monotherapy without the need for traditional preventive treatment in refractory migraine sufferers improving side effect profile and treatment adherence for a cohort of patients difficult to treat.

OnabotulinumtoxinA in Migraine: A Review of the Literature and Factors Associated with Efficacy

The efficacy of onabotulinumtoxinA (OnaB-A) as a preventative treatment for chronic migraine, emerging fortuitously from clinical observation is now supported by class one evidence and over two decades of real-world clinical data. There is still limited ability to predict a clinically meaningful response to OnaB-A for individual patients, however. This review summarises briefly the proposed mechanism of OnaB-A in chronic migraine, the literature of predictors of clinical response, and recent developments in the field.

Daily Headache in Chronic Migraine Is a Predictive Factor of Response in Patients Who Had Completed Three Sessions of OnabotulinumtoxinA

OnabotulinumtoxinA is one of the main preventive treatments for chronic migraine. Despite that up to one third of patients with chronic migraine suffer from daily headache, these individuals have hardly been studied. We conducted a prospective cohort study, including patients with chronic migraine and treated with OnabotulinumtoxinA according to the PREEMPT paradigm. The primary endpoint was to assess whether patients with chronic migraine and daily headache had a different response after three sessions of OnabotulinutoxinA than patients without daily headache. The secondary endpoint was to analyse the presence of predictive factors that could be associated with a higher response to OnabotulinumtoxinA. Patients with daily headache had a reduction of 14.9 (SD: 9.7) headache days per month, patients with 22–29 headache days a reduction of 10.6 (SD: 9.9) days, and patients with 15–21 headache days a reduction of 8.6 (SD: 7.1) days (p < 0.001). In the univariate regression analysis, a higher number of headache days per month at baseline was associated with higher odds of reduction in the number of headache days per month after OnabotulinumtoxinaA treatment (OR: 0.474, 95% CI: 0.278–0.670, p < 0.001). This association was maintained in the multivariate regression analysis (OR: 0.540, 95% CI: 0.333–0.746, p < 0.001). In our sample, daily headache was not associated with a worse response to OnabotulinumtoxinA treatment. A higher frequency of headache at baseline was a predictor of better response to OnabotulinumtoxinA treatment.

Cognitive Function and White Matter Lesions in Medication-Overuse Headache

Purpose

This study was designed to investigate the cognitive function and the white matter lesions (WMLs) and the relationship between them in medication-overuse headache (MOH) patients.

Methods

Subjects were enrolled and performed Montreal Cognitive Assessment (MoCA, Chinese-Beijing Version), Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD-24), and Pittsburgh Sleep Quality Index (PSQI) to evaluate the general cognitive function, anxiety, depression and sleep quality, and they were divided into three groups according to the MoCA scores: healthy controls, MOH with normal cognition group and MOH with cognitive impairment group. All the participants underwent MRI scans and images were obtained for WML evaluation with Fazekas scale.

Results

One hundred thirty-four participants were enrolled into this study, 46 of them for healthy controls, and 88 for MOH patients, 40 of the MOH patients for MOH with cognitive impairment group, and 48 for MOH with normal cognition group. MOH patients had significantly lower MoCA scores, including the scores of visuospatial and executive function, attention, and orientation, while they had significantly greater HAMA scores, HAMD-24 scores, PSQI scores, and deep white matter hyperintensity scores compared to healthy controls. And in MOH patients, the age, disease duration, monthly headache days, and periventricular white matter hyperintensity scores in patients with cognitive impairment were greater than those in patients with normal cognition. Moreover, the MoCA scores were negatively related to age, disease duration, monthly headache days, and Fazekas scale scores, and disease duration and monthly headache days were significant predictors of cognitive impairment in MOH patients.

Conclusion

MOH patients showed cognitive impairment and increased WML burden. And in MOH patients, cognitive function was negatively related to WML burden, and disease duration and monthly headache days were potential predictors of cognitive impairment. Prompt and effective treatment to stop the progression of the disease may alleviate cognitive impairment in MOH patients.

Early Management of OnabotulinumtoxinA Treatment in Chronic Migraine: Insights from a Real-Life European Multicenter Study

Introduction

OnabotulinumtoxinA (BT-A) quarterly was the first treatment approved specifically for chronic migraine (CM). It is unclear whether three cycles are better than two to assess early BT-A response.

Methods

We performed a retrospective analysis on real-life prospectively collected data in 16 European headache centers. All the centers provided data on patients treated with BT-A for CM over the first three cycles of treatment. For each treatment cycle we defined patients as “good responders” if reporting a ≥ 50% reduction in monthly headache days compared with the three months before starting BT-A, “partial responders” if reporting a 30–49% reduction in monthly headache days, and “non-responders” if reporting a < 30% reduction in monthly headache days or stopping the treatment before the third cycle.

Results

We included 2879 patients. Seven hundred and eighty-four (64.6%) of the 1213 patients reporting a good response during the first and/or the second cycle had a good response during the third cycle; 309 (49.3%) of the 627 patients reporting a partial response (but no good response) during the first and/or the second cycle had a good response during the third cycle; only 65 (6.3%) of the 1039 patients who did not respond during both the first two cycles achieved a good response during the third cycle. Multivariate analyses showed that partial or good response during the first or the second cycle were independently associated with good response during the third cycle.

Conclusions

Our data suggest that patients with CM responding to BT-A during the first two cycles will likely benefit from the third cycle of treatment, while the probability that non-responders to the first two cycles start responding during the third cycle is low. These results can help guide the individual decision to stop or continue treatment after the second cycle in patients who have not responded to the first two cycles.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00253-0.

Efficacy of Galcanezumab for Migraine Prevention in Patients With a Medical History of Anxiety and/or Depression: A Post Hoc Analysis of the Phase 3, Randomized, Double-Blind, Placebo-Controlled REGAIN, and Pooled EVOLVE-1 and EVOLVE-2 Studies

OBJECTIVE

This post hoc analysis evaluated the efficacy of galcanezumab for the prevention of migraine in patients with and without comorbid anxiety and/or depression.

BACKGROUND

Patients with migraine have a higher risk of anxiety and/or depression. Given the high prevalence of psychiatric symptoms and their potential negative prognostic impact, determining the efficacy of migraine treatments in patients with these comorbidities is important.

METHODS

The results of 2 phase 3 episodic migraine studies of patients with 4-14 migraine headache days (MHD) per month were pooled. A third chronic migraine study, which was evaluated separately, enrolled patients with ≥15 headache days per month, of which ≥8 had migraine-like features. Patients in all 3 studies were randomized 2:1:1 to placebo, galcanezumab 120 mg, or galcanezumab 240 mg. The efficacy of galcanezumab on migraine was measured in subgroups of patients with anxiety and/or depression (current or past) and patients without. A repeated measures model was used to compare treatment groups within each subgroup and to test for consistency of treatment effect across the anxiety/depression subgroups (subgroup-by-treatment interaction) during the double-blind treatment phases.

RESULTS

Among 1773 intent-to-treat patients with episodic migraine, both doses of galcanezumab demonstrated statistically significant improvements relative to placebo in overall number of MHD for the subgroups of patients with anxiety and/or depression (mean change difference from placebo [95% CI]: -2.07 [-2.81, -1.33] for galcanezumab 120 mg [P < .001], -1.91 [-2.78, -1.04] for 240 mg [P < .001]) and without anxiety and/or depression (mean change difference from placebo [95% CI]: -1.92 [-2.36, -1.47] for 120 mg [P < .001], -1.77 [-2.20, -1.33] for 240 mg [P < .001]), as was observed for the secondary outcomes of MHD with acute medication use and functional impairment. Among 1113 intent-to-treat patients with chronic migraine, those with anxiety and/or depression had significant reductions in overall MHD frequency with the 240-mg dose (mean change difference from placebo [95% CI]: -1.92 [-3.52, -0.33]; P = .018), whereas significant reductions were observed at both the 120-mg (mean change difference from placebo [95% CI]: -2.29 [-3.26, -1.31]; P < .001) and 240-mg (-1.85 [-2.83, -0.87]; P < .001) doses in patients without anxiety and/or depressions. Significant reductions (P < .01) in MHD with acute medication use were observed at both doses within both anxiety/depression subgroups and for overall functional impairment for patients without anxiety and/or depression, though neither dose significantly reduced overall functional impairment beyond placebo in the subgroup with anxiety and/or depression. In the episodic and chronic migraine studies, the subgroup-by-treatment interaction was not statistically significant for MHD, MHD with acute medication use, or functional impairment (chronic study only), suggesting a lack of evidence of differential effect between subgroups. Furthermore, differences between subgroups in the mean change differences from placebo, as well as overlapping 95% confidence intervals for the subgroups, indicated lack of a clinical or statistical difference between subgroups for these outcome variables. There was a significantly higher percentage of patients with episodic migraine attaining ≥50%, ≥75%, and 100% reductions, and a higher percentage of patients with chronic migraine attaining ≥50% and ≥75% reductions from baseline with galcanezumab compared with placebo, regardless of medical history of anxiety and/or depression.

CONCLUSIONS

A medical history of anxiety and/or depression does not seem to interfere with response to galcanezumab among patients with episodic migraine, and both doses of galcanezumab appear efficacious for these individuals regardless of this psychiatric history. Among patients with chronic migraine and comorbid anxiety and/or depression, the 240-mg dose, but not the 120-mg dose, significantly decreased overall MHD, but neither dose resulted in significantly greater functional improvement. Patients with migraine and comorbid anxiety and/or depression often require additional interventions, and this may be more important in chronic migraine.

Perceived Ineffectiveness of Pharmacological Treatments for Dysmenorrhea

Background: Dysmenorrhea affects most reproductive-aged women. Common dysmenorrhea treatments vary in their effectiveness across individuals. Little is known about factors associated with perceived treatment ineffectiveness. The objectives of this study were to describe the perceived ineffectiveness of common pharmacological treatments for dysmenorrhea and investigate factors associated with perceived treatment ineffectiveness. Materials and Methods: In this cross-sectional study, 678 women with dysmenorrhea (aged 14-42) provided data on perceived treatment ineffectiveness, dysmenorrhea symptom-based phenotypes, demographics, clinical factors, and psychobehavioral characteristics. We used Fisher's exact tests to compare treatment ineffectiveness across three symptom-based phenotypes. We used logistic regressions to explore associations of phenotype, demographic, clinical, and psychobehavioral correlates of perceived treatment ineffectiveness. Results: Percentages perceiving treatments as ineffective were 29.3%-35.6% nonsteroidal anti-inflammatory drugs, 49.9% acetaminophen, and 39.3% combined oral contraceptive pills (OCPs). Factors associated with perceived ineffectiveness varied across treatments and included symptom-based phenotypes, clinical, and psychobehavioral factors. For ibuprofen and acetaminophen, women with severe (vs. mild) pain phenotype and higher number of chronic pain conditions were more likely to perceive the treatments as ineffective. For OCPs, women with severe pain (vs. mild) phenotype, comorbid gynecological condition, less anxiety, and worse depressive symptoms were more likely to perceive the treatment as ineffective. Conclusion: A significant percentage of women reported ineffectiveness of dysmenorrhea treatments. Phenotypes, clinical, and psychobehavioral factors were associated with treatment ineffectiveness. Future research should test if symptom-based phenotypes are associated with treatment effectiveness in clinical trials and investigate other factors that affect dysmenorrhea treatment effectiveness, so treatments can be tailored to individuals.

Exploring Emotional Distress, Psychological Traits and Attitudes in Patients with Chronic Migraine Undergoing OnabotulinumtoxinA Prophylaxis versus Withdrawal Treatment

This explorative cross-sectional study aims at exploring emotional distress, psychological profiles, and the attitude towards receiving psychological support in eighty-seven patients with chronic migraine (CM) undergoing OnabotulinumtoxinA prophylactic treatment (OBT-A, n = 40) or withdrawal treatment (WT, n = 47). The outcomes were explored through a specific battery of questionnaires. 25% of patients undergoing OBT-A and almost half of the patients undergoing WT reported psychological distress of at least moderate-severe level, respectively. Coping strategies, self-efficacy, and perceived social support were similar in the two groups. Patients undergoing OBT-A presented lower psychological inflexibility than patients undergoing WT. Predictors of higher psychological distress were low perceived social support by friends, low self-efficacy, and higher avoidance strategies. In both groups, most of the patients evaluated receiving psychological support to be useful (79%). The potential beneficial effects of OBT-A on the severity of symptoms and psychological distress might further support its role in the multidisciplinary management of patients with CM. Identifying patients with psychological vulnerabilities who may benefit from psychological support is relevant in patients with CM.

Iron Deposits in Periaqueductal Gray Matter Are Associated with Poor Response to OnabotulinumtoxinA in Chronic Migraine

Previous studies have reported increased brain deposits of iron in patients with chronic migraine (CM). This study aims to determine the relation between iron deposits and outcome after treatment with OnabotulinumtoxinA (OnabotA). Demographic and clinical data were collected for this study through a prospective cohort study including 62 CM patients treated with OnabotA in the Hospital Clínico Universitario de Santiago de Compostela (Spain). Demographic and clinical variables were registered. Selected biomarkers in plasma during interictal periods (calcitonin gene-related peptide (CGRP) and pentraxin-3 (PTX3)) and neuroimaging changes (iron deposits in the red nucleus (RN), substantia nigra (SN), globus pallidus (GP), and periaqueductal gray matter (PAG), and white matter lesions (WML)) were determined. Subjects were classified in responders (≥50% reduction in headache days) or non-responders (<50%). Responders to treatment were younger (mean age difference = 12.2; 95% confidence interval (CI): 5.4–18.9, p = 0.001), showed higher serum levels of CGRP (≥50 ng/mL) and PTX3 (≥1000 pg/mL) and smaller iron deposits in the GP and PAG (mean difference = 805.0; 95% CI: 37.9–1572.1 μL, p = 0.040 and mean difference = 69.8; 95% CI: 31.0–108.6 μL, p = 0.008; respectively). Differences in PAG iron deposits remained significant after adjusting for age (mean difference = 65.7; 95% CI: 22.8–108.6 μL, p = 0.003) and were associated with poor response to OnabotA after adjustment for clinical and biochemical variables (odds ratio (OR) = 0.963; 95% CI: 0.927–0.997, p = 0.041). We conclude that larger PAG iron deposits are associated with poor response to OnabotA in CM.

Sustained response to onabotulinumtoxin A in patients with chronic migraine: real-life data

Background

Treatment with onabotulinumtoxin A (BT-A) is safe and effective for chronic migraine (CM). Several studies assessed possible predictors of response to treatment with BT-A, but there is little knowledge on the frequency and predictors of sustained response. The aim of this study was to evaluate sustained response to BT-A in patients with CM.

Main body

In this prospective open-label study, 115 patients with CM and treated with BT-A were consecutively enrolled in two Italian headache centers and followed up for 15 months. Anytime responders were defined as those patients who achieved a ≥ 50% reduction in headache days during any three-month treatment cycle compared with the 3 months prior to initiation of BT-A treatment. Sustained responders were defined as those who achieved a ≥ 50% reduction in headache days within the third treatment cycle and maintained response until the end of follow-up. Non-responders were defined as those patients who never achieved a ≥ 50% reduction in headache days during the follow-up. Headache characteristics prior to BT-A treatment were assessed in order to evaluate their ability in predicting treatment response.

The 115 enrolled patients (84.3% female; median age 50 years) had a median migraine duration of 30 years (interquartile range 22–38). At the end of follow-up, 66 patients (57.4%) were classified as anytime responders. Among the 51 patients who achieved a clinical response within the third month of treatment, 33 (64.7%) were sustained responders. Patients with sustained response had a lower CM duration (median 31 vs 65 months; P = 0.030) and a lower number of headache days (median 25 vs 30; P = 0.013) at baseline compared with non-responders.

Conclusions

About two thirds of patients who gain ≥50% response to BT-A within the third cycle of treatment maintain this positive response over time. More recent onset of CM and more headache-free days at baseline are associated with sustained response. We suggest not to delay preventive treatment of CM with BT-A, in order to increase the likelihood to achieve sustained clinical response.

The Use of Botulinum Toxin in the Management of Headache Disorders

Tremendous progress has been made in the past decades for the treatment of headache disorders. Chronic migraine is the most disabling type of headache and requires the use of acute and preventive medications, many of which are associated with adverse events that limit patient adherence. Botulinum toxin (BoNT) serotype A, a neurotoxin derived from certain strains of Clostridium, disrupts neuropeptide secretion and receptor translocation related to trigeminal nociception, thereby preventing pain sensitization through peripheral and possibly central mechanisms. Ever since the first randomized controlled trial on onabotulinumtoxinA (onabotA) for migraine was published two decades ago, onabotA has been the only BoNT formulation approved for use in the prevention of chronic migraine. Superior tolerability and efficacy have been demonstrated on multiple migraine endpoints in many controlled trials and real-life studies. OnabotA is a safe and efficacious treatment for chronic migraine and possibly high-frequency episodic migraine. Further research is still needed to understand its mechanism of action to fully develop its therapeutic potential.