Preventive therapy with galcanezumab for two consecutive cluster bouts in patients with episodic cluster headache: an observational multicenter study.

BACKGROUND: Cluster headache is a severe and disabling primary headache disorder. Galcanezumab is a monoclonal antibody against calcitonin gene-related peptide and a preventive therapy for episodic cluster headache. However, the approval and insurance coverage for episodic cluster headache differ in each country. Additionally, the consistency of efficacy of galcanezumab therapy has not yet been evaluated. This study aimed to assess the efficacy and safety of 240 mg of galcanezumab therapy for consecutive cluster bouts in patients with episodic cluster headache. METHODS: The study enrolled patients with episodic cluster headache who received two courses of galcanezumab therapy at three university hospitals in Republic of Korea between February 2020 and April 2022. The efficacy and safety of galcanezumab were analyzed by comparing daily headache frequency, the number of headache days, and headache intensity and adverse effects during the one-week period before and the third week after galcanezumab injection for each episode of cluster bouts. Paired t-test was used for comparing repeated data from different episodes of cluster bout. RESULTS: Sixteen patients were enrolled in this study. Fourteen patients received galcanezumab therapy for two consecutive cluster bouts. Galcanezumab was administered 24 days and 11 days after the first and second cluster bouts, respectively. The proportion of patients with 50% or more reduction in frequency of daily headache at week 3 from baseline was 86% and 64% during the first and second episodes, respectively. The proportion of patients who received transitional therapy before galcanezumab therapy was higher in the first episode of cluster bout than that in the second episode of cluster bout. No serious adverse reactions or significant differences in adverse effects between cluster bouts were noticed. Two patients received a second galcanezumab therapy during the pre-cluster period, and their cluster periods ended without typical cluster headache attacks 10-60 days after galcanezumab therapy. CONCLUSIONS: This exploratory analysis suggests that galcanezumab may be effective as a preventive therapy in subsequent cluster bouts. Patients with episodic cluster headaches who underwent galcanezumab therapy tended to receive a second round of treatment in the early stages of their next cluster bout without transitional therapy.

Current treatment options for cluster headache: limitations and the unmet need for better and specific treatments-a consensus article.

AIM: Treatment for cluster headache is currently based on a trial-and-error approach. The available preventive treatment is unspecific and based on few and small studies not adhering to modern standards. Therefore, the authors collaborated to discuss acute and preventive treatment in cluster headache, addressing the unmet need of safe and tolerable preventive medication from the perspectives of people with cluster headache and society, headache specialist and cardiologist. FINDINGS: The impact of cluster headache on personal life is substantial. Mean annual direct and indirect costs of cluster headache are more than 11,000 Euros per patient. For acute treatment, the main problems are treatment response, availability, costs and, for triptans, contraindications and the maximum use allowed. Intermediate treatment with steroids and greater occipital nerve blocks are effective but cannot be used continuously. Preventive treatment is sparsely studied and overall limited by relatively low efficacy and side effects. Neurostimulation is a relevant option for treatment-refractory chronic patients. From a cardiologist's perspective use of verapamil and triptans may be worrisome and regular follow-up is essential when using verapamil and lithium. CONCLUSION: We find that there is a great and unmet need to pursue novel and targeted preventive modalities to suppress the horrific pain attacks for people with cluster headache.

Preventive treatment of refractory chronic cluster headache: systematic review and meta-analysis.

BACKGROUND: Preventive treatment for refractory chronic cluster headache (rCCH) is challenging and many therapies have been tried. OBJECTIVE: To study what could be considered the therapy of choice in rCCH through a systematic review and meta-analysis. METHODS: This review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol was registered in PROSPERO (ID CRD42021290983). A systematic search was performed in MEDLINE, Embase, Cochrane, clinicaltrials.gov, and the WHO's-International-Clinical-Trials-Registry-Platform. Studies on the preventive treatment for rCCH as defined by the European Headache Federation consensus statement were included. A meta-analysis of the pooled response rate was conducted for the different therapies. RESULTS: Of 336 results, 45 were eligible for inclusion. Most articles studied the effect of neuromodulation as a preventive treatment for rCCH. The most studied neuromodulation technique was occipital nerve stimulation (ONS), with a pooled response rate in the meta-analysis of 57.3% (95% CI 0.481-0.665). Deep brain stimulation (DBS) was the second most studied treatment with a pooled response rate of 77.0% (95% CI 0.594-0.957). DBS results were more heterogeneous than ONS, which could be related to the different stimulation targets in DBS studies, and reported more serious adverse events than in ONS studies. The remaining therapies (anti-CGRP pathway drugs, warfarin, ketamine-magnesium infusions, serial occipital nerve blocks, clomiphene, onabotulinum toxin A, ketogenic diet, sphenopalatine ganglion radiofrequency or stimulation, vagus nerve stimulation, percutaneous bioelectric current stimulation, upper cervical cord stimulation, and vidian neurectomy) present weaker results or have less quality of evidence. CONCLUSIONS: The results of this systematic review and meta-analysis suggest that ONS could be the first therapeutic strategy for patients with rCCH based on the current evidence.

Real-world experience with 240 mg of galcanezumab for the preventive treatment of cluster headache.

BACKGROUND: Galcanezumab of 300 mg monthly is the FDA approved preventive medication for cluster headache (CH) during the cluster period. Compared to the 120 mg galcanezumab syringe for the treatment of migraines, the 100 mg syringe for CH has globally not been as widely available. The aim of our study was to investigate the preventive efficacy and tolerability of two 120 mg galcanezumab doses for episodic CH in clinical practices. METHODS: We evaluated patients with CH who received at least 1 dose of 240 mg (2 prefilled syringe of 120 mg) of galcanezumab in the 3 university hospitals from February 2020 to September 2021. In the patients with episodic CH, the efficacy and safety data of galcanezumab were analyzed regarding to the presence of the conventional preventive therapy at the timing of therapy of galcanezumab. The data of other subtypes of CH were separately described. RESULTS: In 47 patients with episodic CH, galcanezumab was started median 18 days after the onset of current bout (range 1-62 days) and 4 patients (10.8%) received second dose of galcanezumab. The median time to the first occurrence of 100% reduction from baseline in CH attacks per week after galcanezumab therapy was 17 days (25% to 75% quartile range: 5.0 ~ 29.5) in all patients with episodic CH, 15.5 days (3.8 ~ 22.1) in 36 patients with galcanezumab therapy add-on conventional preventive therapy, 21.0 days (12.0 ~ 31.5) in 11 patients started galcanezumab as initial preventive therapy. Among 33 patients with headache diary, the proportion of patients with 50% or more reduction in weekly CH attacks at week 3 from baseline were 78.8%. There was no significant difference in the proportion of patients with a reduction of at least 50% in weekly frequency of CH attacks at week 3 between 24 patients received galcanezumab therapy add-on conventional preventive therapy and 9 patient who received initial galcanezumab therapy. (83.3%, vs 66.7%, p = 0.36). There were no significant differences in proportion of "very much better or "much better" between 36 patients received galcanezumab therapy add-on conventional preventive therapy and 11 patient who received initial GT (86.1%, vs 63.6%, p = 0.18). CONCLUSION: One 240 mg dose of galcanezumab with/without conventional therapy for the prevention of CH is considered effective and safe in clinical practices, as seen in the clinical trial of galcanezumab.

Challenges and complexities in designing cluster headache prevention clinical trials: A narrative review.

OBJECTIVE: To provide a review of challenges in clinical trials for the preventive treatment of cluster headache (CH) and highlight considerations for future studies. BACKGROUND: Current guidelines for preventive treatment of CH are largely based on off-label therapies supported by a limited number of small randomized controlled trials. Guidelines for clinical trial design for CH treatments from the International Headache Society were last issued in 1995. METHODS/RESULTS: Randomized controlled clinical trials were identified in the European and/or United States clinical trial registries with a search term of "cluster headache," and manually reviewed. Cumulatively, there were 27 unique placebo-controlled prevention trials for episodic and/or chronic CH, of which 12 were either ongoing, not yet recruiting, or the status was unknown. Of the remaining 15 trials, 5 were terminated early and 7 of the 10 completed trials enrolled fewer patients than planned or did not report the planned sample size. A systematic search of PubMed was also utilized to identify published manuscripts reporting results from placebo-controlled preventive trials of CH. This search yielded 16 publications, of which 7 were registered. Through critical review of trial data and published manuscripts, challenges and complexities encountered in clinical trials for the preventive treatment of CH were identified. For example, the excruciating pain associated with CH demands a suitably limited baseline duration, rapid treatment efficacy onset, and poses a specific issue regarding duration of investigational treatment period and length of exposure to placebo. In episodic CH, spontaneous remission as part of natural history, and the unpredictability and irregularity of cluster periods across patients present additional key challenges. CONCLUSIONS: Optimal CH trial design should balance sound methodology to demonstrate efficacy of a potential treatment with patient needs and the natural history of the disease, including unique outcome measures and endpoint timings for chronic versus episodic CH.

Effects of acute and preventive therapies for episodic and chronic cluster headache: A scoping review of the literature.

BACKGROUND: Cluster headache is the most common primary headache disorder of the trigeminal autonomic cephalalgias, and it is highly disabling. OBJECTIVE: We undertake a scoping review to characterize therapies to prevent and acutely treat cluster headache, characterize trial methodology utilized in studies, and recommend future trial "good practices." We also assess homogeneity of studies and feasibility for future network meta-analyses (NMAs) to compare acute and preventive treatments for cluster headache. METHODS: A priori protocol for this scoping review was registered and available on Open Science Forum. We sought studies that enrolled adult patients with cluster headache as identified by accepted diagnostic criteria. Both randomized controlled trials (RCTs) and observational studies (with a control group) were included. The interventions of interest were medications, procedures, devices, surgeries, and behavioral/psychological interventions, whereas comparators of interest were placebo, sham, or other active treatments. Outcomes were predefined; however, we did not exclude studies lacking these outcomes. A systemic search was conducted in Ovid Medline, Embase, and Cochrane. We performed a targeted search for conference abstracts from journals prominent in the field. RESULTS: We identified 56 studies: 45 RCTs, four studies only available in clinical trial registries, and seven observational studies. Of the 45 RCTs, 20 focused on acute therapies and 25 on preventive therapies. Overall, we determined that it is feasible to pursue a NMA for acute therapy focusing on 15 or 30-min headache reduction for acute trials, as we identified 11 trials in the combined population of patients with either episodic or chronic cluster headache (2 trials in populations with chronic cluster headache were also found). For preventive therapy of cluster headache, we identified trials with common outcomes that may be considered for NMA, however, as these trials had differences in treatment effect modifiers that could not be corrected, NMAs appear infeasible for this indication. We identified new studies looking at noninvasive vagal nerve stimulation, sphenopalatine ganglion stimulation, prednisone, and oxygen published since the most recent systematic review in the field, although these acute treatments were previously identified as effective. However, for calcitonin gene-related peptide (CGRP) monoclonal antibodies, galcanezumab demonstrated effectiveness in episodic cluster headache, but a lack of effectiveness in chronic cluster headache, and fremanezumab was not effective for episodic nor chronic cluster headache. This finding highlights that CGRP monoclonal antibodies may not show a class effect in cluster headache prevention and need to be considered individually. CONCLUSIONS: We describe the treatment landscape of cluster headache for both acute and preventive treatments. Last, we present the NMAs we will undertake in acute therapies of cluster headache.

2022 Taiwan Guidelines for Acute and Preventive Treatment of Cluster Headaches.

The Treatment Guideline Subcommittee of the Taiwan Headache Society evaluated Taiwan's guidelines for the acute and preventive treatment of cluster headaches on the basis of the principles of evidence-based medicine. The subcommittee assessed the quality of clinical trials and levels of evidence and referred to the treatment guidelines of other countries. Over the course of several panel discussions, the subcommittee members reached a consensus regarding the major roles of, recommended levels of, clinical efficacy of, adverse events in, and clinical precautions for the acute and preventive treatment of cluster headaches. Thus, the subcommittee updated the previous version of the guidelines published in 2011. Most cluster headaches occurring in Taiwan are episodic, and very few patients develop chronic cluster headaches. Cluster headaches cause extreme pain over a short period and are accompanied by ipsilateral autonomic symptoms; therefore, immediate treatment can provide considerable relief. Treatment options can be categorized into acute and preventive types. Among the treatment methods currently available in Taiwan for cluster headaches, high-flow pure oxygen inhalation has demonstrated the best evidence and effectiveness for acute attacks, followed by triptan nasal spray; therefore, these are recommended as first-line treatments. Oral steroids and suboccipital steroid injections can be used as transitional preventative treatments. Verapamil is recommended as a first-line treatment for maintenance prophylaxis. Drugs such as lithium, topiramate, and calcitonin gene-related peptide (CGRP) monoclonal antibodies are recommended as secondline treatments. Noninvasive vagus nerve stimulation is the recommended instrumental therapy. The effectiveness of surgical treatment, such as sphenopalatine ganglion stimulation, is supported by a high level of evidence; nevertheless, because few patients have chronic cluster headaches in Taiwan, no clinical records are available for use as a reference. Transitional prophylaxis and maintenance prophylaxis can be used simultaneously according to the individual condition of the patient, and the transitional prophylaxis can be gradually discontinued once the maintenance prophylaxis takes effect. Steroids should not be used for more than 2 weeks as transitional prophylaxis. Maintenance prophylaxis should be administered until the end of the bout period (no attacks for 2 weeks) and then gradually tapered off. Key words: cluster headaches, oxygen therapy, triptans, steroids, CGRP monoclonal antibodies, noninvasive vagus nerve stimulation.

Drug Treatment of Cluster Headache.

Cluster headache belongs to the group of trigeminal autonomic headaches. This review summarizes drug therapy of cluster attacks and prophylactic treatment. Neurostimulation methods are not addressed. The therapy for acute cluster attacks includes inhalation of 100% oxygen, subcutaneous administration of sumatriptan, and intranasal application of sumatriptan or zolmitriptan. Bridging therapy, which is used until oral prophylactic therapy is effective, is performed either with oral prednisolone or with a pharmacological block of the major occipital nerves. Best documented drugs for preventive treatment of cluster headache are verapamil and lithium, and possibly effective drugs are gabapentin, topiramate, divalproex sodium, and melatonin. The efficacy of monoclonal antibodies to the calcitonin gene-related peptide so far has been only demonstrated for episodic cluster headache. Several drug therapies are being investigated including ketamine, onabotulinumtoxinA, lysergic acid, and sodium oxybate.

Recently available and emerging therapeutic strategies for the acute and prophylactic management of cluster headache: a systematic review and expert opinion.

Introduction: Although it causes a huge burden to sufferers, cluster headache (CH), remains an undertreated condition, partly due to the absence of established acute and prophylactic treatment options. New therapeutic approaches providing fast and safe relief from CH are needed. Areas covered: A systematic review was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendation on recently published (last 5 years) papers on CH treatment. The authors also collected preliminary results from ongoing trials on emerging therapeutic/preventive pharmacological and interventional approaches for CH. Studies and results are reviewed and discussed. Expert opinion: The complexity of CH pathophysiology prevents the definition of reliable acute and preventive treatments. In the real-world clinical setting, several treatments are combined to provide relief to patients and increase their quality of life. Drugs targeting neuropeptides or their receptors within the trigeminovascular network are of particular interest to prevent CH attacks. Calcitonin gene-related peptide (CGRP) blockade seems attractive and promising, but studies on anti-CGRP monoclonal antibodies indicated rather modest or even absence of a prophylactic effect. A deeper insight into CH pathophysiology, and combined approaches may lead the path to new, more effective, and personalized CH therapies.

Safety and efficacy of prednisone versus placebo in short-term prevention of episodic cluster headache: a multicentre, double-blind, randomised controlled trial.

BACKGROUND: Prednisone is commonly used for initial short-term therapy of episodic cluster headaches before preventive medication such as verapamil becomes effective, but this strategy has not been tested in large randomised trials. We aimed to access the safety and efficacy of this treatment approach. METHODS: This study was a multicentre, randomised, double-blind, placebo-controlled trial done in ten specialised headache centres in Germany. Patients with episodic cluster headaches who were aged between 18 and 65 years and within a current pain episode for not more than 30 days, received 100 mg oral prednisone for 5 days followed by tapering of 20 mg every 3 days, or matching placebo (17 days total exposure). All patients received oral verapamil for long-term prevention, starting with 40 mg three times daily and increasing to 120 mg three times daily by day 19; patients then continued with verapamil 120 mg throughout the study. Randomisation was computer-generated at a 1:1 ratio by use of an interactive web-response system, with stratification according to age, sex, and participating site. Participants, investigators, and those assessing outcomes were unaware of treatment allocation. The primary endpoint was the mean number of attacks within the first week of treatment with prednisone compared with placebo. An attack was defined as a unilateral headache with moderate-to-severe intensity of at least five on a numerical rating scale. All efficacy and safety analyses were done in the modified intention-to-treat (mITT) population, which consisted of all patients who had been randomly assigned to a trial group and received at least one dose of prednisone or placebo. The study was stopped early due to slow recruitment and expired funding. The study was registered with EudraCT (2011-006204-13) and with the German Clinical Trials Register (DRKS00004716). FINDINGS: Between April 5, 2013, and Jan 11, 2018, 118 patients were enrolled in the study. Two patients dropped out immediately and 116 patients were randomly assigned (57 patients to prednisone and 59 patients to placebo); 109 patients were included in the mITT analysis (53 patients assigned to prednisone and 56 patients assigned to placebo). Participants in the prednisone group had a mean of 7·1 (SD 6·5) attacks within the first week compared with 9·5 (6·0) attacks in the placebo group (difference -2·4 attacks, 95% CI -4·8 to -0·03; p=0·002). Two serious adverse events occurred, both in the placebo group (inguinal hernia and severe deterioration of cluster headache). A total of 270 adverse events were observed: in the prednisone group, 37 (71%) of 52 patients reported 135 adverse events (most common were headache, palpitations, dizziness, and nausea) and in the placebo group, 39 (71%) of 55 patients had 135 adverse events (most common were nausea, dizziness, and headache). INTERPRETATION: Oral prednisone was an effective short-term preventive therapy in our population of patients with episodic cluster headache. Our findings support the use of prednisone as a first-line treatment in parallel to the up-titration of verapamil, although the efficacy of prednisone alongside other long-term prevention requires additional investigation. FUNDING: German Federal Ministry for Education and Research.

Cluster headache: state of the art of pharmacological treatments and therapeutic perspectives.

Cluster headache (CH) is the most common form of trigeminal autonomic cephalalgia. Current treatments have several limitations, and new drugs are required. This article first briefly reviews present acute and preventive treatments in CH, their mechanism of action and limitations, then describes the state of the art in recent clinical drug trials since 2015, and ends with a critique of trials in the CH field. Research is limited by lack of knowledge of pathophysiology and lack of animal models. In the past 5 years, no brand-new treatment has emerged, but promising drugs, such as CGRP(R) antibodies, are under study. According to the literature and guidelines, clinicians and researchers should be aware of many limitations in study protocols: concomitant medication, patient sample size, patients' protocol compliance, and study designs that tend to restrict patient recruitment.

Drug profile: galcanezumab for prevention of cluster headache.

Introduction: Cluster headache [CH] is a severely disabling trigeminal autonomic cephalalgia [TAC]. Approximately 1 in 1,000 adults are affected by CH. Calcitonin gene-related peptide [CGRP] is an important mediator in the pathophysiology of CH. Galcanezumab is a monoclonal antibody with an affinity for the CGRP peptide, FDA approved for the prevention of episodic CH. Areas covered: Search words queried were 'cluster headache,' 'cluster headache, and CGRP,' 'cluster headache, and galcanezumab.' Over 99 articles in Pubmed and prescribing information for galcanezumab were reviewed. Some of the data pertaining to CH trials with fremanezumab were reviewed using clinical trials.org. Expert opinion: Galcanezumab has shown benefit in decreasing the weekly frequency of CH attacks across week 1 through week 3 in patients with CH; 8.7 attacks in the galcanezumab group, as compared with 5.2 in the placebo group (95% confidence interval, 0.2 to 6.7; P = 0.04). It has a favorable risk-benefit ratio. The prevention of CH with CGRP inhibition represents a novel advance for a condition with a significant unmet need. The negative trial results of galcanezumab for chronic cluster headache [CCH] may be due to the refractory nature and sheds light on the critical need to investigate the underlying biology and therapeutic options.

Treatment Outcomes in Patients Treated With Galcanezumab vs Placebo: Post Hoc Analyses From a Phase 3 Randomized Study in Patients With Episodic Cluster Headache.

BACKGROUND: Cluster headache (CH) is a highly disabling primary headache disorder. To date, characterization of outcomes in the preventive treatment of episodic CH, including precise definitions of clinically meaningful attack frequency reduction and impact on acute treatment management, is lacking. METHODS: This was a Phase 3, randomized, double-blind, placebo-controlled study in patients (men or women aged 18-65 years) diagnosed with episodic CH as defined by the International Classification of Headache Disorders-3 beta criteria. In this post hoc analysis, we evaluated the median time-to-first occurrence of ≥50, ≥75, or 100% reduction from baseline in CH attack frequency, and impact on acute medication use. An anchor-based assessment of clinically relevant attack frequency reduction using the Patient Global Impression of Improvement (PGI-I) scores at Week 4 was also assessed. RESULTS: The median time-to-first occurrence of ≥50, ≥75, or 100% reduction from baseline in CH attacks was consistently shorter (9-10 days sooner) with galcanezumab vs placebo (median [95% confidence interval, 95% CI]: ≥50%, 5 days [4.0 to 7.0] vs 14 days [6.0 to 19.0]; ≥75%, 11 days [7.0 to 16.0] vs 21 days [13.0 to 26.0]; 100%, 22 days [16.0 to 37.0] vs 32 days [23.0 to 34.0]). Mean reduction from baseline in the overall frequency of weekly pooled acute medication use across Weeks 1-3 was significantly greater with galcanezumab vs placebo (11.0 vs 5.5; odds ratio, OR [95% CI]: 5.52 [1.02, 10.01]; P value = .017). Patients reporting "much better" on the PGI-I experienced a median weekly CH attack reduction of approximately 43% from baseline across Weeks 1-3. The overall odds of achieving an attack reduction threshold of 43% across Weeks 1-3 was significantly higher with galcanezumab vs placebo (Weeks 1-3: OR [95% CI], 2.60 [1.3 to 5.3]). CONCLUSIONS: Faster median time-to-first occurrence of response rates, lower frequency of pooled acute medications use, and a greater proportion of patients achieving a response anchored by patient-reported improvement were observed for galcanezumab vs placebo.

Deep Brain Stimulation for Chronic Cluster Headache: Meta-Analysis of Individual Patient Data.

OBJECTIVE: Deep brain stimulation (DBS) is a treatment option for refractory chronic cluster headache (CCH). Despite several recent prospective case series reporting a good outcome, the effectiveness and the optimal stimulation target of DBS for CCH remain unclear. We aimed to obtain precise estimates and predictors of long-term pain relief in an individual patient data meta-analysis. Furthermore, we aimed to construct a probabilistic stimulation map of effective DBS. METHODS: We invited investigators of published cohorts of patients undergoing DBS for CCH, identified by a systematic review of MEDLINE from inception to Febuary 15, 2019, to provide individual patient data on baseline covariates, pre- and postoperative headache scores at median (12-month) and long-term follow-up, in addition to individual imaging data to obtain individual electrode positions. We calculated a stimulation map using voxel-wise statistical analysis. We used multiple regression analysis to estimate predictors of pain relief. RESULTS: Among 40 patients from four different cohorts representing ~50% of all previously published cases, we found a significant 77% mean reduction in headache attack frequency over a mean follow-up of 44 months, with an overall response rate of 75%. Positive outcome was not associated with baseline covariates. We identified 2 hotspots of stimulation covering the midbrain ventral and retrorubral tegmentum. INTERPRETATION: This study supports the hypothesis that DBS provides long-term pain relief for the majority of CCH patients. Our stimulation map of the region of influence of therapeutic DBS identified an optimal anatomical target site that can help surgeons to guide their surgical planning in the future. ANN NEUROL 2020;88:956-969.

Galcanezumab for the prevention of cluster headache.

INTRODUCTION: Cluster headache (CH) is among the worst painful conditions. The available therapies are scarce and not specific, leaving many patients unsatisfied because of poor efficacy and/or tolerability. Patients not responding to common treatments are offered semi-invasive and invasive procedures with uncertain results. Based on the current understanding of CH pathophysiology, new possible therapeutic approaches come from drugs interfering with Calcitonin Gene Related Peptide (CGRP). AREAS COVERED: After summarizing the evidence for CGRP involvement in CH pathophysiology, we review the published literature (PubMed) and information (clinicaltrials.gov, EudraCT, EMA and FDA websites) regarding a novel anti-CGRP monoclonal antibody, Galcanezumab, its pharmacological properties, development, and evidence for the treatment of CH. Publications regarding other indications (migraine) are considered for completeness and safety/tolerability profile. EXPERT OPINION: In one randomized clinical trial, Galcanezumab has proven to be effective and safe as a preventive treatment in episodic CH, with a favorable tolerability profile offering a potential new option in the therapeutic arsenal. Inefficacy of galcanezumab in chronic CH as well as the inefficacy of another monoclonal antibody against CGRP (fremanezumab) in both episodic and chronic CH question the scalability of the drug in CH management. Further, studies comparing galcanezumab to the current standard treatments are highly desirable.

Cluster headache therapies: pharmacology and mode of action.

INTRODUCTION: Cluster headache (CH) is the most common trigeminal autonomic cephalalgia with a significant need for novel treatment options. While the use of most of the acute CH medications is supported by clinical trials and based on a pathophysiological concept for the generation of pain, the scientific evidence for preventive CH medications is very limited. AREAS COVERED: This article reviews acute and preventive substances for the pharmacological treatment of CH with a focus on the mode of action of these drugs. We also summarized the clinical trial evidence and discuss future research directions. EXPERT OPINION: Recommendations for current pharmacological CH therapies, in particular for CH prevention, are often based on small open label studies with inconclusive results. Larger trials are missing. A shared pathophysiological mechanism of action of these preventatives does not exist. Future studies with CGRP(R) antibodies and novel substances with specific actions are needed and will thereby help to understanding the pathophysiology of CH.

Erenumab Efficacy on Comorbid Cluster Headache in Patients With Migraine: A Real-World Case Series.

BACKGROUND: Monoclonal antibodies (mABs) against calcitonin gene-related peptide (CGRP) or its receptor have emerged as effective and well-tolerated preventive medications for migraine. The key role played by CGRP has been recently demonstrated also in the pathophysiology of cluster headache (CH), paving the way for studies aimed to investigate the effectiveness of mABs targeting CGRP also in CH. However, no trials have been conducted so far to test the efficacy and tolerability of erenumab as CH preventive treatment. CASE SERIES: We describe the cases of 5 patients with both migraines and CH with previous failures of preventive treatments. All patients were treated with monthly erenumab (70 or 140 mg) showing good results not only on migraine but also on CH attacks frequency and intensity. Improvements of both intensity and frequency of CH attacks occurred only after at least 3 months of treatment, with monthly erenumab 140 mg, suggesting that longer treatment and higher doses are needed in CH in comparison to migraine. DISCUSSION AND CONCLUSION: Our findings support the efficacy and tolerability of monthly erenumab 140 mg as a preventive treatment in patients suffering from both migraines without aura and CH. We speculate that erenumab could represent a low-risk alternative for CH patients (with or without comorbid migraine) who did not tolerate common CH preventatives therapies or for whom the therapies were not successful. Certainly, randomized trials are needed to confirm these observations and we hope that our data, showing a delayed therapeutic effect only with the highest dose of erenumab (140 mg/month), can be taken into account in designing future trials.

Neuromodulation for the Acute and Preventive Therapy of Migraine and Cluster Headache.

Headache disorders are among the most common and disabling medical conditions worldwide. Pharmacologic acute and preventive treatments are often insufficient and poorly tolerated, and the majority of patients are unable to adhere to their migraine treatments due to these issues. With improvements in our understanding of migraine and cluster headache pathophysiology, neuromodulation devices have been developed as safe and effective acute and preventive treatment options. In this review, we focus on neuromodulation devices that have been studied for migraine and cluster headache, with special attention to those that have gained food and drug administration (FDA) clearance. We will also explore how these devices can be used in patients who might have limited pharmacologic options, including the elderly, children, and pregnant women.