Identifying and managing refractory migraine: barriers and opportunities?

Ultra-late response (> 24 weeks) to anti-CGRP monoclonal antibodies in migraine: a multicenter, prospective, observational study

OBJECTIVE

Nearly 60% of migraine patients treated with monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway experience a ≥ 50% reduction in monthly migraine days (MMD) at 12 weeks compared to baseline (responders). However, approximately half of the patients not responding to anti-CGRP mAbs ≤ 12 weeks do respond ≤ 24 weeks (late responders). We assessed frequency and characteristics of patients responding to anti-CGRP mAbs only > 24 weeks (ultra-late responders).

METHODS

In this multicenter (n = 16), prospective, observational, real-life study, we enrolled all consecutive adults affected by high-frequency episodic migraine (HFEM: ≥ 8 days/month) or chronic migraine (CM), with ≥ 3 prior therapeutic failures, treated with any anti-CGRP mAbs for ≥ 48 weeks. We defined responders patients with a ≥ 50% response rate ≤ 12 weeks, late responders those with a ≥ 50% response rate ≤ 24 weeks, and ultra-late responders those achieving a ≥ 50% response only > 24 weeks.

RESULTS

A total of 572 migraine patients completed ≥ 48 weeks of anti-CGRP mAbs treatment. Responders accounted for 60.5% (346/572), late responders for 15% (86/572), and ultra-late responders for 15.7% (90/572). Among ultra-late responders, 7.3% (42/572) maintained the ≥ 50% response rate across all subsequent time intervals (weeks 28, 32, 36, 40, 44, and 48) and were considered persistent ultra-late responders, while 8.4% (48/572) missed the ≥ 50% response rate at ≥ 1 subsequent time interval and were classified as fluctuating ultra-late responders. Fifty patients (8.7%) did not respond at any time interval ≤ 48 weeks. Ultra-late responders differed from responders for higher BMI (p = 0.033), longer duration of medication overuse (p < 0.001), lower NRS (p = 0.017) and HIT-6 scores (p = 0.002), higher frequency of dopaminergic symptoms (p = 0.002), less common unilateral pain-either alone (p = 0.010) or in combination with UAS (p = 0.023), allodynia (p = 0.043), or UAS and allodynia (p = 0.012)-a higher number of comorbidities (p = 0.012), psychiatric comorbidities (p = 0.010) and a higher proportion of patients with ≥ 1 comorbidity (p = 0.020).

CONCLUSION

Two-thirds of patients not responding to anti-CGRP mAbs ≤ 24 weeks do respond later, while non-responders ≤ 48 weeks are quite rare (8.7%). These findings suggest to rethink the duration of migraine prophylaxis and the definition of resistant and refractory migraine, currently based on the response after 2-3 months of treatment.

Real-world effectiveness and satisfaction with intravenous eptinezumab treatment in patients with chronic migraine: REVIEW, an observational, multi-site, US-based study

BACKGROUND

Despite recent advancements in migraine treatment, some patients continue to endure significant disease burden. Due to the controlled nature of randomized trials in migraine prevention, many real-world patients with comorbidities or prior exposure to certain therapies are excluded. Capturing evidence of the effectiveness of treatment in real-world clinical settings can further shape treatment paradigms. The objective of this study was to develop a comprehensive understanding of both patients' and physicians' real-world experiences with eptinezumab for chronic migraine (CM).

METHODS

REVIEW (Real-world EVidence and Insights into Experiences With eptinezumab) is an observational, multi-site (n = 4), US-based study designed to evaluate real-world experiences of patients treated with eptinezumab and their treating physicians. Patients were ≥ 18 years of age, with a diagnosis of CM, who had completed ≥ 2 consecutive eptinezumab infusion cycles (≥ 6 months of exposure). The study included a retrospective chart review, a patient survey, and a semi-structured physician interview that assessed patient and/or physician satisfaction with elements of daily living / well-being, migraine symptomology, and perspectives of the eptinezumab infusion experience.

RESULTS

Of the 94 patients enrolled, 83% (78/94) were female, the mean age was 49.2 years, and the mean time since migraine diagnosis was 15.4 years. Before eptinezumab treatment, patients experienced a mean of 8 self-reported "good" days/month, which increased to 18 after treatment. Most patients took, on average, ≥ 10 days/month of prescription and/or over-the-counter medication (81% [75/93] and 66% [61/93], respectively) to treat migraine attacks before eptinezumab treatment, which dropped to 26% (24/93) and 23% (21/93) following eptinezumab treatment. Prior to receiving eptinezumab, 62% (58/93) of patients indicated being at least slightly concerned about infusions; after eptinezumab infusion, this dropped to 14% (13/93). These patient survey findings were consistent with physician responses.

CONCLUSION

This real-world evidence study demonstrated high overall satisfaction with the effectiveness of eptinezumab treatment for CM among most patients and their physicians.

Resistant and refractory migraine: clinical presentation, pathophysiology, and management

Migraine is a leading cause of disability worldwide. A minority of individuals with migraine develop resistant or refractory conditions characterised by ≥ 8 monthly days of debilitating headaches and inadequate response, intolerance, or contraindication to ≥3 or all preventive drug classes, respectively. Resistant and refractory migraine are emerging clinical definitions stemming from better knowledge of the pathophysiology of migraine and from the advent of migraine-specific preventive treatments. Resistant migraine mostly results from drug failures, while refractory migraine has complex and still unknown mechanisms that impair the efficacy of preventive treatments. Individuals with resistant migraine can be treated with migraine-specific preventive drugs. The management of refractory migraine is challenging and often unsuccessful, being based on combinations of different drugs and non-pharmacological treatment. Future research should aim to identify individuals at risk of developing treatment failures, prevent the condition, investigate the mechanisms of refractoriness to treatments, and find effective treatment strategies.

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.

Late Response to Anti-CGRP Monoclonal Antibodies in Migraine: A Multicenter Prospective Observational Study

OBJECTIVES

To assess the frequency and characteristics of late responders (>12 weeks) to monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP).

METHODS

This is a multicenter (n = 16) prospective real-life study considering all consecutive adults with high-frequency or chronic migraine treated with anti-CGRP mAbs for ≥24 weeks. We defined responder patients with a ≥50% reduction from baseline in monthly migraine/headache days at weeks 9-12 and late responders as those achieving a ≥50% reduction only afterward.

RESULTS

A total of 771 people with migraine completed ≥24 weeks of anti-CGRP mAb treatment. Responders at 12 weeks were 65.6% (506/771) of the patients, while nonresponders were 34.4% (265/771). A total of 146 of the 265 nonresponders (55.1%) at 12 weeks responded afterward (late responders): they differed from responders for a higher BMI (+0.78, 95% CI [0.10; 1.45]; p = 0.024), more frequent treatment failures (+0.52, 95% CI [0.09; 0.95]; p = 0.017) and psychiatric comorbidities (+10.1%, 95% CI [0.1; 0.20]; p = 0.041), and less common unilateral pain, alone (-10,9%, 95% CI [-20.5; -1.2]; p = 0.025) or in combination with unilateral cranial autonomic symptoms (-12.3%, 95% CI [-20.2;-3.9]; p = 0.006) or allodynia (-10.7, 95% CI [-18.2; -3.2]; p = 0.01).

DISCUSSION

Half of nonresponders to anti-CGRP mAbs at 12 weeks are indeed late responders. Efficacy of anti-CGRP mAbs should be assessed at 24 weeks while treatment duration should be extended beyond 12 months.

Algorithm-based approach to headache

One of the most commonly encountered scenarios in any healthcare setting is a patient presenting with a headache. Yet, the assessment, diagnosis and treatment of headache disorders can be challenging and burdensome for even specialist doctors in medicine, psychiatry, oto-rhinology, neurology and so on. Apart from saving patient's and doctor's time as well as money, this article will buy leading time for better outcome and management of certain difficult headache disorders. The aim of this review is to simplify the approach to headache diagnosis for an early and proper referral. Literature search was done on PubMed and Google Scholar using key words. Only studies which were in English were considered. Sixty-one articles published from 1975 to 2022 were reviewed after screening for inclusion and exclusion criteria. It is very essential that a primary care physician is aware of the classification of headache. Red flag signs of high-risk headaches are essential for proper referral. It is also essential that we rule out secondary headaches as they are more life threatening. Vulnerable populations such as geriatric and paediatric populations require expert attention in case of headache disorders.

Medium-term real-world data for erenumab in 177 treatment resistant or difficult to treat chronic migraine patients: persistence and patient reported outcome measures after 17-30 months

BACKGROUND

Many migraine patients do not respond adequately to conventional preventive treatments and are therefore described as treatment/medically resistant or difficult to treat cases. Calcitonin gene-related peptide monoclonal antibodies are a relatively novel molecular treatment for episodic and chronic migraine that have been shown to be effective in short duration clinical trials in approximately 40-50% of all chronic migraine patients. Patient Related Outcome Measures (PROM) or Quality of Life (QoL) questionnaires are used to help measure response to treatment in migraine. Although some open label extension studies have become available for erenumab, there is a lack of real-world data pertaining to quality of life in the medium to long-term for chronic and treatment resistant migraine patients.

METHODS

A total of 177 treatment resistant CM patients were started on erenumab (70 mg or 140 mg subcutaneous injection every 4 weeks) in our three specialist Headache Clinics. Of these, 174 had their first injection between December 2018 and October 2019. All patients were evaluated with the following PROM: the Headache Impact Test- 6, Migraine Associated Disability Assessment test and Migraine-Specific QoL Questionnaire, before starting treatment with erenumab and at intervals of 3-12 months after starting treatment. The decision to continue treatment was based on subjective clinical improvement of at least 30% (as reported by the patient), supported with diaries and QoL questionnaires. We present here the QoL measurements for this group of 177 patients. Prior preventive migraine treatments included conventional oral prophylactic medications (such as topiramate, candesartan, propranolol, or amitriptyline), at least two cycles of PREEMPT protocol onabotulinumtoxin A or (in a small number of cases) neuromodulation with single pulse Transcranial Magnetic Stimulation.

RESULTS

Of the 177 patients who started treatment with erenumab, 68/177 (38.4%) stopped during the first year, either due to lack of efficacy (no significant benefit or only minimal improvement) and/or possible side effects. 109/177 (61.6%) patients reported clinically significant improvement after 6-12 months and wished to stay on treatment. Twelve of these 109 patients subsequently stopped treatment in the period between 1 year and up to June 2021 (mainly due to a worsening of their migraine). Therefore, a total of 97/177 patients (54.8%) remained on treatment as of June 2021 (duration of treatment 17-30 months, median of 25 months).

CONCLUSION

Approximately 55% of treatment resistant or difficult to treat CM patients who trialled erenumab in our clinics reported a subjective benefit and were still on treatment after 17-30 months.

Management of Episodic Migraine with Neuromodulation: A Case Report

Migraine is a highly prevalent neurovascular disorder that affects approximately 15% of the global population. Migraine attacks are a complex cascade of neurologic events that lead to debilitating symptoms and are often associated with inhibitory behavior. The constellation of severe signs and symptoms during the ictal phase (headache attack) makes migraine the third most common cause of disability globally in both sexes under the age of 50. Misuse of pharmaceuticals, such as opiates, can lead to devastating outcomes and exacerbation of pain and headache attacks. A safe and well-tolerated non-pharmacological research approach is high-definition transcranial direct current stimulation over the M1.

Rate and Predictors of Intractable Status Migrainosus among Patients Aged 13-18 Years

Purpose

To assess associations for intractable status migrainosus in the pediatric inpatient setting.

Methods

A retrospective cohort study of 1,805 patients presenting to the pediatric hospital in Dayton, Ohio with status migrainosus from 2017 to 2022, was performed. Among 1,805 patients, 159 received 3 lines of sequentially more aggressive abortive migraine treatment and were included in this analysis. Responders and non-responders were categorized based on a visual analogue scale (VAS) of pain scores from time of admission to discharge with responders having a reduction of 50% or greater in VAS. Patient demographic information, migraine history, headache type, medication history, self-reported pain, anxiety level and co-morbidities were assessed.

Results

Out of 159 patients, 125 (78.6%) achieved the target pain control with decrease in VAS pain score by ≥ 50% from the baseline. The remaining 34/159 (21.4%) patients remained refractory to treatment. Non-responder patients had a longer hospital stay (6.1 days) and greater readmission rate within 7 days (17.6%) compared to responders (4.7 days and .8% respectively). Among the non-responder patients, 14/34 (41.2%) had attention-deficit/hyperactivity disorder (ADHD) compared to the responder group in which 17/125 (13.6%) had ADHD. Among patients who had comorbidity of anxiety, non-responders had greater severe generalized anxiety disorder (GAD-7 ≥15) (6/14, 42.9%) than responders (2/39, 5.1%).

Conclusion

ADHD and severe GAD are associated with poorer response to treatment in pediatric patients with refractory migraine admitted for inpatient therapy. This study highlights the prolonged hospital stay and modest clinical outcomes seen with intractable migraine in 13-18-year-old pediatric patients.

Two-year effectiveness of erenumab in resistant chronic migraine: a prospective real-world analysis

Background

Controlled and real-world evidence have demonstrated the efficacy of calcitonin gene related peptide (CGRP) monoclonal antibodies (MABs) in migraine. However, data on the over-one-year sustained effectiveness of CGRP MABs in resistant chronic migraine (CM) is sparse. 

Methods

This is a two-year real-world prospective analysis of an ongoing single centre audit conducted in patients with resistant CM. Patients received monthly erenumab for six months before assessing its effectiveness. Responders were considered those who achieved at least 30% reduction in monthly migraine days (MMD) by month 6, compared to baseline. Secondary outcomes were also analysed, including changes of the Headache Impact Test version 6 (HIT-6).

Results

One hundred sixty-four patients [135 (82.3%) females; mean age 46 SD 14) years] were included in the audit and 160 patients analysed. Patients had failed a mean of 8.4 preventive treatments at baseline. At month 6, 76 patients (48%) were 30% responders to erenumab, 50 patients (31%) were 50% responders and 25 (15%) were 75% responders. The mean reduction in MMD at month 6 was 7.5 days compared to baseline (P < 0.001). At month 12 and month 18, 61 patients (38%) and 52 patients (33%) remained 30% responders respectively. At month 24, 36 patients (23%) remained 30% responders, 25 patients (16%) and 13 patients (8%) were respectively 50% and 75% responders. Compared to 95% of patients at baseline, at months 6, 12 and 24, 46%, 29% and 16% of responders respectively had severe disability. At least one adverse event at month 6, 12, 18 and 24 was reported by 49%, 19%, 11% and 3% of patients. By month 6, 13% of patients discontinued the treatment because of side effects, often constipation.

Conclusions

Long-term sustained effectiveness of erenumab was reported only by a minority of resistant CM patients. Although more research in resistant migraine is needed, Erenumab can provide long-term meaningful reduction in migraine load and migraine-related disability in some patients.

Long-Term Follow-Up Safety and Effectiveness of CT-Guided Radiofrequency Thermocoagulation of Sphenopalatine Ganglion in Refractory Headache Treatment

OBJECTIVE

The purpose of this study was to evaluate the effectiveness and safety of computed tomography (CT)-guided radiofrequency thermocoagulation (RFTA) of the sphenopalatine ganglion (SPG) for patients with refractory headache.

METHODS

A total of 14 patients with refractory migraine and 10 patients with cluster headache (CH) who underwent CT-guided SPG RF between May 2019 and August 2021 at the Jiaxing First Hospital, located in Jiaxing City, Zhejiang Province, China, were included and analyzed in this retrospective cohort study. Pain score, sleep quality scores, and treatment effects were observed before operation as well as 1 day and 1, 3, 6, 12, and 24 months after surgery. Also, the incidence of facial numbness at different timepoints after operation was evaluated.

RESULTS

The frequency and duration of attacks decreased after treatment in patients with migraine, and the shortening of the cluster period and the prolongation of the remission period after treatment in patients with CH indicated that the treatment was effective. The numeric rating scale (NRS) ranged from 0 to 10, where 0 meant no pain and 10 meant the worst imaginable pain. The NRS of patients at 1 day and 1, 3, 6, 12, and 24 months after surgery was significantly lower than before operation (P < 0.05). The treatment of patients with migraine and CH was effective. The overall incidence of numbness in patients with migraine and the total incidence of numbness in patients with CH was recorded. The total incidence of numbness decreased gradually, but no significant difference was detected in the incidence of numbness between the two groups (P > 0.05). No serious adverse reactions, such as orthostatic hypertension, intracranial infection, and visual disturbance, occurred in the patients after operation.

CONCLUSION

CT-guided RFTA of the SPG significantly relieves headache symptoms in patients with refractory migraine and CH. It has the advantages of rapid onset, long duration, and a safe and reliable treatment process, making it worthy of clinical application.

Recently approved and emerging drug options for migraine prophylaxis

INTRODUCTION

: Migraine occupies the first position regarding to the disability caused in female working population (15-49 years). Research in the field of prophylaxis of this pathology has made enormous strides in recent years.

AREAS COVERED

In this narrative review we retrace the most important scientific evidence regarding recently approved and emerging drug for prophylactic treatment of migraine. The purpose of this article is in fact to evaluate currently approved or emerging pharmacological agents for migraine prophylaxis. This review is based on literature published in peer review journal obtained through PubMed, Cochrane library, Clinicaltrials.gov and US FDA.

EXPERT OPINION

: Monoclonal antibodies (mAbs) that target the calcitonin gene-related peptide signalling pathway (CGRP) have marked an innovation in prophylactic migraine therapy. The combination of Onabotulinumtoxin-A (OBTA) and mAbs appears to be an effective, but costly, therapeutic option for resistant cases. New classes of molecules like gepants and ditans seem to give exceptional results. In addition, new prophylactic drugs are emerging with several targets: the pituitary adenylate cyclase-activating polypeptide (PACAP), ion channels, several receptors coupled to G proteins, orexin, and glutamate. All these therapies will implement and improve migraine management, as well as personalized medicine for each patient.

A Markov Analysis of Surgical versus Medical Management of Chronic Migraines

BACKGROUND

Refractory chronic migraine is a common and debilitating neurologic condition, affecting over 8 million people in the United States. It is associated with billions of dollars in lost productivity annually. Novel medical (anti-calcitonin gene-related peptide antibodies) and surgical treatment modalities have emerged for chronic migraine in recent years. The current study investigated the cost-utility of surgical versus medical management of refractory chronic migraine.

METHODS

A Markov cohort analysis using hybrid Monte Carlo patient simulation was performed to compare surgical decompression versus erenumab for the treatment of refractory chronic migraine in adults. Both societal and payer perspectives were considered. Primary model outcomes included incremental cost-effectiveness ratio, or cost per quality-adjusted life-year gained.

RESULTS

Over a 5-year period, migraine surgery was associated with an increase of 0.2 quality-adjusted life-year per patient when compared to erenumab. In terms of costs, the results demonstrated a $19,337 decrease in direct medical costs and a $491 decrease in indirect costs (productivity lost) for the surgery cohort compared to erenumab. Because surgery improved quality of life and decreased costs compared to erenumab, even when considering revision surgery needs, surgery was the overall dominant treatment in terms of cost-effectiveness. Sensitivity analyses demonstrated that surgery was cost-effective compared to erenumab when patients required therapy for at least 1 year.

CONCLUSIONS

Surgical deactivation of migraine trigger sites may pose a cost-effective approach to treating refractory chronic migraine in adults. This is especially the case when patients are anticipated to require therapy for more than 1 year.

Predictors of clinical response to erenumab in patients with migraine

Background:

Anti-CGRP monoclonal antibodies have emerged as efficacious preventive therapies for some, but not all patients with migraine. It is not yet fully understood what predicts treatment response.

Objective:

To identify factors associated with good or poor response to erenumab, the first available CGRP monoclonal antibody.

Methods:

A chart review of patients with migraine from a large headache center who received at least three 4-weekly doses of erenumab between 2018 and 2020 was conducted. Clinical variables were compared between erenumab responders (defined as ≥30% reduction in monthly headache or migraine days at 3 months) and non-responders via logistic regression analyses.

Results:

Among 90 enrolled patients, 62.2% were erenumab responders and 37.8% non-responders. A significantly larger proportion of non-responders were unemployed (58.8% vs. 28.6%), had complex diagnosis (chronic migraine overlapping another primary or secondary headache) (47.1% vs. 14.3%), higher monthly headache days (30 vs. 25.5) and migraine days (20 vs. 12), a higher frequency of daily headache (76.5% vs. 48.2%), and failed more preventive therapies (5.5 vs. 3). Based on logistic regressions, erenumab responsiveness did not significantly associate with duration of migraine, presence of aura, medication overuse, number of concurrent preventives, response to onabotulinumtoxinA or triptans, or certain comorbidities and substance use.

Conclusions:

This work may help improve selection of patients who may benefit from erenumab, but further prospective research studies are needed.

Screening for Copy Number Variations of the 15q13.3 Hotspot in CHRNA7 Gene and Expression in Patients with Migraines

Background: a migraine is a neurological disease. Copy number variation (CNV) is a phenomenon in which parts of the genome are repeated. We investigated the effects of the CNV and gene expression at the location 15q13.3 in the Cholinergic Receptor Nicotinic Alpha 7 Subunit (CHRNA7) gene, which we believe to be effective in the migraine clinic. Methods: we evaluated changes in CHRNA7 gene expression levels and CNV of 15q13.3 in patients with migraine (n = 102, with aura, n = 43; without aura, n = 59) according to healthy controls (n = 120) by q-PCR. The data obtained were analyzed against the reference telomerase reverse transcriptase (TERT) gene with the double copy number by standard curve analysis. Copy numbers were graded as a normal copy (2), gain (2>), and loss (<2). Results: we analyzed using the 2^−ΔΔCT calculation method. The CHRNA7 gene was significantly downregulated in patients (p < 0.05). The analysis of CNV in the CHRNA7 gene was statistically significant in the patient group, according to healthy controls (p < 0.05). A decreased copy number indicates a dosage loss. However, no significant difference was observed among gain, normal, and loss copy numbers and expression values in patients (p > 0.05). The change in CNV was not associated with the downregulation of the CHRNA7 gene. Conclusion: Downregulation of the CHRNA7 gene may contribute to the formation of migraine by inactivation of the alpha-7 nicotinic receptor (α7nAChR). The association of CNV gains and losses with migraines will lead to better understanding of the molecular mechanisms and pathogenesis, to better define the disease, to be used as a treatment target.

OnabotulinumtoxinA for the prophylactic treatment of headaches in adult patients with chronic migraine: a safety evaluation

Introduction: Existing oral prophylaxis for chronic migraine (CM) are often ineffective or poorly tolerated. OnabotulinumtoxinA (onabotA) is approved for headache prophylaxis in CM and ameliorates headaches in patients refractory to multiple preventatives.Areas covered: We appraise evidence regarding action mechanisms, pharmacodynamics, and pharmacokinetics of onabotA in CM prophylaxis. We critically evaluate salient clinical and real-world studies demonstrating its efficacy in improving multiple aspects of CM. We discuss onabotA safety, tolerability, and adverse events (AEs) for CM prophylaxis from clinical trials, post-authorization studies and meta-analyses, including novel pregnancy safety data and comparisons with oral prophylactics. We explore areas of future interest, particularly onabotA safety and efficacy in the context of novel antibody-based prophylaxis.Expert opinion: Clinical and real-world evidence demonstrate onabotA safety, tolerability and efficacy for CM prophylaxis. Most AEs are mild/moderate and self-limiting, with few serious AEs and no treatment-related deaths. Common AEs include neck pain, ptosis, muscle weakness, and stiffness. Modifying existing responder-criteria enables more patients to benefit from onabotA. OnabotA shows superior safety and efficacy to oral preventatives, and appears safe in pregnancy. Future pregnancy-risk register will clarify pregnancy and lactation safety further. Future research comparing onabotA safety and efficacy with newly emergent antibody-based prophylaxis is keenly awaited.

Dietary alteration of n-3 and n-6 fatty acids for headache reduction in adults with migraine: randomized controlled trial

OBJECTIVE

To determine whether dietary interventions that increase n-3 fatty acids with and without reduction in n-6 linoleic acid can alter circulating lipid mediators implicated in headache pathogenesis, and decrease headache in adults with migraine.

DESIGN

Three arm, parallel group, randomized, modified double blind, controlled trial.

SETTING

Ambulatory, academic medical center in the United States over 16 weeks.

PARTICIPANTS

182 participants (88% women, mean age 38 years) with migraines on 5-20 days per month (67% met criteria for chronic migraine).

INTERVENTIONS

Three diets designed with eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and linoleic acid altered as controlled variables: H3 diet (n=61)-increase EPA+DHA to 1.5 g/day and maintain linoleic acid at around 7% of energy; H3-L6 diet (n=61)-increase n-3 EPA+DHA to 1.5 g/day and decrease linoleic acid to ≤1.8% of energy; control diet (n=60)-maintain EPA+DHA at <150 mg/day and linoleic acid at around 7% of energy. All participants received foods accounting for two thirds of daily food energy and continued usual care.

MAIN OUTCOME MEASURES

The primary endpoints (week 16) were the antinociceptive mediator 17-hydroxydocosahexaenoic acid (17-HDHA) in blood and the headache impact test (HIT-6), a six item questionnaire assessing headache impact on quality of life. Headache frequency was assessed daily with an electronic diary.

RESULTS

In intention-to-treat analyses (n=182), the H3-L6 and H3 diets increased circulating 17-HDHA (log ng/mL) compared with the control diet (baseline-adjusted mean difference 0.6, 95% confidence interval 0.2 to 0.9; 0.7, 0.4 to 1.1, respectively). The observed improvement in HIT-6 scores in the H3-L6 and H3 groups was not statistically significant (-1.6, -4.2 to 1.0, and -1.5, -4.2 to 1.2, respectively). Compared with the control diet, the H3-L6 and H3 diets decreased total headache hours per day (-1.7, -2.5 to -0.9, and -1.3, -2.1 to -0.5, respectively), moderate to severe headache hours per day (-0.8, -1.2 to -0.4, and -0.7, -1.1 to -0.3, respectively), and headache days per month (-4.0, -5.2 to -2.7, and -2.0, -3.3 to -0.7, respectively). The H3-L6 diet decreased headache days per month more than the H3 diet (-2.0, -3.2 to -0.8), suggesting additional benefit from lowering dietary linoleic acid. The H3-L6 and H3 diets altered n-3 and n-6 fatty acids and several of their nociceptive oxylipin derivatives in plasma, serum, erythrocytes or immune cells, but did not alter classic headache mediators calcitonin gene related peptide and prostaglandin E2.

CONCLUSIONS

The H3-L6 and H3 interventions altered bioactive mediators implicated in headache pathogenesis and decreased frequency and severity of headaches, but did not significantly improve quality of life.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02012790.

Safety and Efficacy of 10 kHz Spinal Cord Stimulation for the Treatment of Refractory Chronic Migraine: A Prospective Long-Term Open-Label Study

BACKGROUND

Refractory chronic migraine (rCM) is a highly disabling condition for which novel safe and effective treatments are needed. Safety and long-term efficacy of paresthesia-free high cervical 10 kHz spinal cord stimulation (SCS) were here prospectively evaluated for the treatment of rCM.

MATERIALS AND METHODS

Twenty adults with rCM (mean numbers of preventive treatments failed: 12.2 ± 3.1) were enrolled in this single-center, open-label, prospective study and implanted with a 10 kHz SCS system (Senza™ system, Nevro Corp.), with the distal tip of the lead(s) positioned epidurally at the C2 vertebral level. Safety and effectiveness outcomes, such as adverse events, headache and migraine reductions, responder rates, Migraine Disability Assessment (MIDAS), Headache Impact Test-6 (HIT-6), and Migraine-Specific Quality-of-Life (MSQ), were captured up to 52 weeks after implantation.

RESULTS

Compared to baseline, at 52 weeks postimplantation, there was a significant reduction of mean monthly migraine days (MMD) by 9.3 days (p < 0.001). Sixty percent and 50% of patients obtained respectively at least 30% and at least 50% reduction in mean MMD. By week 52, 50% of patients' chronic pattern converted to an episodic pattern. The proportion of subjects classified with severe headache-related disability on the HIT-6, decreased from 100% to 60% at week 52. Meaningful improvements of headache-related quality of life measured by the MSQ scale were observed with mean gain of 24.9 ± 23.1 (p < 0.001) points at 52 weeks. No unanticipated adverse device effects occurred. No patients required any additional device surgical revision.

CONCLUSION

10 kHz SCS may a be safe and effective neurostimulation option for rCM patients. The paresthesia-free waveform constitutes an unprecedented advantage for future methodologically sound sham-controlled studies in headache neuromodulation.

Approach to Pediatric Intractable Migraine

PURPOSE OF REVIEW

Intractable migraine in children and adolescents is a significant cause of disability and decreased quality of life (QoL) in this population. Challenges include lack of unifying definition for intractable migraine, and limited data on best-practice management in this age group, with most current treatment pathways extrapolated from adult studies or expert consensus.

RECENT FINDINGS

A comprehensive approach in the evaluation and management of intractable migraine in this age group encompasses excluding secondary causes of headache; making an accurate diagnosis; identifying and appropriately managing modifiable risk factors; and initiating appropriate pharmacologic therapy to reduce disability, improve health-related quality of life, reduce risk of progression, and develop adaptive pain coping strategies. Several strategies for management of pediatric intractable migraine including use of acute medications, bridge therapy in outpatient setting, emerging therapies for preventive therapy, and a stepwise combination therapy for management of pediatric intractable migraine in emergency and inpatient setting are presented based on available clinical data, safety/tolerability, availability, cost-effectiveness, and expert consensus. This descriptive review of the available literature focuses on approach to therapy for acute intractable migraine in a pediatric population including outpatient, emergency department (ED), and inpatient management.

Galcanezumab for the prevention of high frequency episodic and chronic migraine in real life in Italy: a multicenter prospective cohort study (the GARLIT study)

Background

The clinical benefit of galcanezumab, demonstrated in randomized clinical trials (RCTs), remains to be quantified in real life. This study aimed at evaluating the effectiveness, safety and tolerability of galcanezumab in the prevention of high-frequency episodic migraine (HFEM) and chronic migraine (CM) in a real-life setting.

Methods

This multicenter prospective observational cohort study was conducted between November 2019 and January 2021 at 13 Italian headache centers. Consecutive adult HFEM and CM patients clinically eligible were enrolled and treated with galcanezumab subcutaneous injection 120 mg monthly with the first loading dose of 240 mg. The primary endpoint was the change in monthly migraine days (MMDs) in HFEM and monthly headache days (MHDs) in CM patients after 6 months of therapy (V6). Secondary endpoints were the Numerical Rating Scale (NRS), monthly painkiller intake (MPI), HIT-6 and MIDAS scores changes, ≥50% responder rates (RR), the conversion rate from CM to episodic migraine (EM) and Medication Overuse (MO) discontinuation.

Results

One hundred sixty-three patients (80.5% female, 47.1 ± 11.7 years, 79.8% CM) were included. At V6, MMDs reduced by 8 days in HFEM and MHDs by 13 days in CM patients (both p < .001). NRS, MPI, HIT-6 and MIDAS scores significantly decreased (p < .001). Ten patients (6.1%) dropped out for inefficacy and classified as non-responders. Patients with ≥50%RRs, i.e. responders, were 76.5% in the HFEM and 63.5% in the CM group at V6. Among CM patients, the V6 responders presented a lower body mass index (p = .018) and had failed a lower number of preventive treatments (p = .013) than non-responders. At V6, 77.2% of CM patients converted to EM, and 82.0% ceased MO. Adverse events, none serious, were reported in up to 10.3% of patients during evaluation times.

Conclusions

Galcanezumab in real life was safe, well tolerated and seemed more effective than in RCTs. Normal weight and a low number of failed preventives were positively associated with galcanezumab effectiveness in CM patients.

Trial registration

ClinicalTrials.govNCT04803513.

Severe migraine and its control: A proposal for definitions and consequences for care

Currently many patients with severe migraine do not receive appropriate treatment and are never referred to specialist headache centres. On the other hand, specialist headache centres are frequently attended by patients whose migraines could be managed adequately in the community. One reason for this may be the absence of standardised definitions of migraine severity and control and of a treatment algorithm for orientating difficult-to-treat patients to specialist headache centres. Based on a review of the relevant literature and consensus meetings, proposals have been made for these items. We propose that migraine should be considered severe if headache frequency is at least eight migraine days per month or, if headaches are less frequent, the HIT-6 score is ≥60 or ≥50% of headaches require complete interruption of activity. The proposed definition of migraine control is defined on the basis of appropriate response to acute headache therapy and to preventative therapy. A treatment algorithm is proposed to assess migraine control regularly and to adapt therapy accordingly. These proposals may contribute to developing and testing strategies for management of severe disease with appropriate and effective preventive treatment strategies. With the anticipated introduction of new possibilities for migraine prevention in the near future, the time is ripe for a holistic approach to migraine management.

The impact of Pain-related emotions on migraine

The response to pain is highly individual and can be influenced by complex emotional perception. This study aims to investigate the status of the pain-related emotional response, and the influence on headache characteristics and disability in migraine. We studied the pain-related emotional response in 145 consecutive migraine patients using the Pain Anxiety Symptoms Scale (PASS), the Pain Catastrophizing Scale (PCS), and the Pain Sensitivity Questionnaire (PSQ) and compared them with 106 healthy controls. We investigated the relationship between emotional factors and migraine characteristics. The effect of pain-related emotion on migraine-related disability assessed with the Headache Impact Test-6 (HIT-6) and the Migraine Disability Assessment (MIDAS). Migraine patients showed significantly higher scores on total PASS (p < 0.001), PCS (p < 0.001) and PSQ (p = 0.002) compared to the healthy controls. The HIT-6 was weakly correlated with PASS (r = 0.390, p < 0.001) and PCS (r = 0.354, p < 0.001). PASS-Total (p = 0.001), headache frequency (p = 0.003), and HADS-Anxiety (p = 0.028) were independent variables associated with HIT-6. Headache frequency (p < 0.001) was an independent variable associated with MIDAS. The structural equation model indicated that headache severity has direct loading on emotion and subsequently influenced migraine-related disability. Disability has a significant effect on the frequency of abortive medication use. Migraine patients have altered emotional responses to pain perception. Pain-related anxiety made an important contribution to headache-related disability. The present results suggest that the management of disability by considering various pain-related emotional factors may be necessary for the therapeutic aspects of migraine.

Refractoriness to drugs in migraine may be the result of developing anti-drug antibodies

INTRODUCTION

Migraine is a common neurological disease and is listed second among the most disabling health conditions worldwide. Refractory migraine (RM) is a term used to emphasize the unresponsiveness of migraine to various treatment options, encompassing both episodic refractory and chronic refractory migraine. In this paper we discuss various known and possible mechanisms of pharmacological refractoriness in RM, such as possible involvement of the gut microbiome, the blood-brain barrier, migraine genetics and various mechanisms of pharmacokinetic and pharmacodynamic tolerance. Development of medication-overuse headache as a secondary disorder following migraine is also considered. We argue that the available literature is insufficient to fully explain the mechanisms of refractoriness and we present our hypothesis.

HYPOTHESIS

Refractoriness to drugs in migraine may be the result of developing anti-drug antibodies. Most migraine drugs are small molecules, which cannot elicit an immune response on their own due to their size. However, such molecules can bind to peptide carriers in their vicinity, greatly increasing their immunogenicity. A small molecule possessing this binding ability is called a hapten. Haptens form hapten-carrier complexes (HCCs), which can evoke powerful immune responses. Immune reactions to HCCs are known to be predominantly 'drug allergies' or type 1 drug hypersensitivity reactions', usually resulting from IgE or non-IgE mediated mast cell degranulation. We argue that the immune reaction to HCCs can take shape in developing neutralizing anti-drug antibodies (ADA) in the form of IgG and IgA class antibodies. Since biological therapeutics, such as various monoclonal antibodies, face the issue of ADA-induced drug tolerance, HCCs, being similar in the sense that they carry peptide antigens, are of sufficient size and may be considerably immunogenic, can be responded to in a similar way by producing neutralizing ADA. Furthermore, we argue that such responses are expected to happen more frequently than is thought, due to IgG and IgA being prevalent antibodies, which utilize their neutralizing capabilities on regular basis. Finally, it is important to consider that neutralization reactions in normal immune responses are typically asymptomatic, with the only clinical expression being progressive drug tolerance. These cases may be overshadowed by the life-threatening cases of drug allergy induced anaphylaxis, possibly leading to neutralization reactions being underrecognized.

DISCUSSION

This hypothesis aims to stimulate more research regarding drug resistance, and if it receives support from empirical evidence, it may help further elucidate the mechanisms underlying refractory diseases and contribute to the development of more effective treatment of many disorders.

Improvements across a range of patient-reported domains with fremanezumab treatment: results from a patient survey study

Background

The long-term safety and efficacy of fremanezumab were evaluated in a 52-week extension study (NCT02638103). Patient satisfaction with fremanezumab, dosing preferences, and patient-reported outcomes were assessed in a subpopulation who completed the extension study and consented to a follow-up questionnaire.

Methods

In the extension study (N = 1842), adults with migraine were randomized to quarterly or monthly fremanezumab. After completing active treatment, patients answered a survey evaluating patient satisfaction, treatment and dosing preferences, and changes in patient-reported outcomes.

Results

Of the 557 patients who could have been contacted upon completing the extension study, 302 consented and 253 completed the survey. The mean (standard deviation) satisfaction rating for fremanezumab was 6.1 (1.4; 1 = “extremely dissatisfied” to 7 = “extremely satisfied”). Most patients (175 [69.2%]) preferred quarterly over monthly fremanezumab dosing. Among patients taking antiepileptics (most common class of prior preventive medication; n = 130), 91.5% preferred fremanezumab. Patients reported improvements in anxiety (74 [67.9%]), sleep quality (143 [56.5%]), and quality of time spent with others (210 [83.0%]) with fremanezumab.

Conclusion

In this study, treatment satisfaction with fremanezumab was high, most patients preferred quarterly fremanezumab dosing, and fremanezumab was generally preferred to prior preventive medications.

Trial registration

ClinicalTrials.gov NCT02638103 (HALO LTS), registered December 22, 2015.

European headache federation consensus on the definition of resistant and refractory migraine : Developed with the endorsement of the European Migraine & Headache Alliance (EMHA)

INTRODUCTION

Despite advances in the management of headache disorders, some patients with migraine do not experience adequate pain relief with acute and preventive treatments. It is the aim of the present document to provide a definition of those migraines which are difficult-to-treat, to create awareness of existence of this group of patients, to help Healthcare Authorities in understanding the implications, and to create a basis to develop a better pathophysiological understanding and to support further therapeutic advances.

MAIN BODY

Definitions were established with a consensus process using the Delphi method. Patients with migraine with or without aura or with chronic migraine can be defined as having resistant migraine and refractory migraine according to previous preventative failures. Resistant migraine is defined by having failed at least 3 classes of migraine preventatives and suffer from at least 8 debilitating headache days per month for at least 3 consecutive months without improvement; definition can be based on review of medical charts. Refractory migraine is defined by having failed all of the available preventatives and suffer from at least 8 debilitating headache days per month for at least 6 consecutive months. Drug failure may include lack of efficacy or lack of tolerability. Debilitating headache is defined as headache causing serious impairment to conduct activities of daily living despite the use of pain-relief drugs with established efficacy at the recommended dose and taken early during the attack; failure of at least two different triptans is required.

CONCLUSIONS

We hope, that the updated EHF definition will be able to solve the conflicts that have limited the use of definitions which have been put forward in the past. Only with a widely accepted definition, progresses in difficult-to-treat migraine can be achieved. This new definition has also the aim to increase the understanding of the impact of the migraine as a disease with all of its social, legal and healthcare implications. It is the hope of the EHF Expert Consensus Group that the proposed criteria will stimulate further clinical, scientific and social attention to patients who suffer from migraine which is difficult-to-treat.

Dual Therapy With Anti-CGRP Monoclonal Antibodies and Botulinum Toxin for Migraine Prevention: Is There a Rationale?

OBJECTIVE

To narratively review the pathophysiological rationale of dual therapy with anti-calcitonin gene-related peptide monoclonal antibodies and botulinum toxin type A in treatment-resistant chronic migraine prevention.

BACKGROUND

For the prevention of chronic migraine, several pharmacological therapies are available, including oral medications, botulinum toxin type A, and the newly approved monoclonal antibodies targeting calcitonin gene-related peptide or its receptor. However, monotherapy does not yield benefits in some affected individuals, which raises the question of whether dual therapy with monoclonal antibodies and botulinum toxin type A hold promise in patients with treatment-resistant chronic migraine.

METHOD

We searched MEDLINE for articles published from database inception to December 31st, 2019. Publications were largely selected from the past 10 years but commonly referenced and highly regarded older publications were not excluded.

RESULTS

Preclinical data suggest that anti-calcitonin gene-related peptide monoclonal antibodies and botulinum toxin type A have synergistic effects within the trigeminovascular system. Of note, findings indicate that fremanezumab - an antibody targeting the calcitonin gene-related peptide - mainly prevents the activation of Aδ-fibers, whereas botulinum toxin type A prevents the activation of C-fibers.

CONCLUSION

There is currently only indirect preclinical evidence to support a rationale for dual therapy with anti-calcitonin gene-related peptide monoclonal antibodies and botulinum toxin type A for chronic migraine prevention. Rigorous studies evaluating clinical efficacy, safety, and cost-effectiveness are needed.

Managing Migraine in the Times of COVID-19 Pandemic

COVID-19 pandemic is an emerging, rapidly evolving situation. Migraine is one of the commonest and highly disabling chronic neurological diseases in the world. During the pandemic and lockdown, migraine patients are facing an enormous problem in getting optimum care because of difficulty in access, forced social isolation, and encountering a health system that is getting rapidly overwhelmed. It is important that they must be protected by minimizing their visits to the clinics and emergency departments. Paradoxically multiple triggers are in operation which is likely to increase their headache frequency. Hence physicians should be made aware of the new rules of the game in treating migraines during this time of the pandemic so that these patients get optimum treatment and care and don't feel left out. This review tries to answer a series of questions related to managing migraines in the times of COVID-19 pandemic.