Long-term follow-up after flunarizine or nimodipine discontinuation in migraine patients

The sense of stopping migraine prophylaxis

INTRODUCTION

Migraine prophylactic therapy has changed over recent years with the development and approval of monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway. As new therapies emerged, leading headache societies have been providing guidelines on the initiation and escalation of such therapies. However, there is a lack of robust evidence looking at the duration of successful prophylaxis and the effects of therapy discontinuation. In this narrative review we explore both the biological and clinical rationale for prophylactic therapy discontinuation to provide a basis for clinical decision-making.

METHODS

Three different literature search strategies were conducted for this narrative review. These include i) stopping rules in comorbidities of migraine in which overlapping preventives are prescribed, notably depression and epilepsy; ii) stopping rules of oral treatment and botox; iii) stopping rules of antibodies targeting the CGRP (receptor). Keywords were utilized in the following databases: Embase, Medline ALL, Web of Science Core collection, Cochran Central Register of Controlled Trials, and Google Scholar.

DISCUSSION

Reasons to guide decision-making in stopping prophylactic migraine therapies include adverse events, efficacy failure, drug holiday following long-term administration, and patient-specific reasons. Certain guidelines contain both positive and negative stopping rules. Following withdrawal of migraine prophylaxis, migraine burden may return to pre-treatment level, remain unchanged, or lie somewhere in-between. The current suggestion to discontinue CGRP(-receptor) targeted mAbs after 6 to 12 months is based on expert opinion, as opposed to robust scientific evidence. Current guidelines advise the clinician to assess the success of CGRP(-receptor) targeted mAbs after three months. Based on excellent tolerability data and the absence of scientific data, we propose if no other reasons apply, to stop the use of mAbs when the number of migraine days decreases to four or fewer migraine days per month. There is a higher likelihood of developing side effects with oral migraine preventatives, and so we suggest stopping these drugs according to the national guidelines if they are well tolerated.

CONCLUSION

Translational and basic studies are warranted to investigate the long-term effects of a preventive drug after its discontinuation, starting from what is known about the biology of migraine. In addition, observational studies and, eventually, clinical trials focusing on the effect of discontinuation of migraine prophylactic therapies, are essential to substantiate evidence-based recommendations on stopping rules for both oral preventives and CGRP(-receptor) targeted therapies in migraine.

[Consensus statement of the migraine and headache societies (DMKG, ÖKSG, and SKG) on the duration of pharmacological migraine prophylaxis]

Migraine is the most common neurological disorder and can be associated with a high degree of disability. In addition to non-pharmacological approaches to reduce migraine frequency, pharmacological migraine preventatives are available. Evidence-based guidelines from the German Migraine and Headache Society (DMKG), and German Society for Neurology (DGN), Austrian Headache Society (ÖKSG), and Swiss Headache Society (SKG) are available for indication and application. For therapy-relevant questions such as the duration of a pharmacological migraine prevention, no conclusions can be drawn from currently available study data. The aim of this review is to present a therapy consensus statement that integrates the current data situation and, where data are lacking, expert opinions. The resulting current recommendations on the duration of therapy for pharmacological migraine prophylaxis are shown here.

[Consensus statement of the migraine and headache societies (DMKG, ÖKSG, and SKG) on the duration of pharmacological migraine prophylaxis]

Migraine is the most common neurological disorder and can be associated with a high degree of disability. In addition to non-pharmacological approaches to reduce migraine frequency, pharmacological migraine preventatives are available. Evidence-based guidelines from the German Migraine and Headache Society (DMKG), and German Society for Neurology (DGN), Austrian Headache Society (ÖKSG), and Swiss Headache Society (SKG) are available for indication and application. For therapy-relevant questions such as the duration of a pharmacological migraine prevention, no conclusions can be drawn from currently available study data. The aim of this review is to present a therapy consensus statement that integrates the current data situation and, where data are lacking, expert opinions. The resulting current recommendations on the duration of therapy for pharmacological migraine prophylaxis are shown here.

Real-world evidence following a mandatory treatment break after a 1-year prophylactic treatment with calcitonin gene-related peptide (pathway) monoclonal antibodies

BACKGROUND

Current German and European guidelines suggest migraine patients undertake a treatment break after 9 to 12 months of treatment with CGRP (pathway) monoclonal antibodies.

METHODS

Clinical routine data of highly resistant migraine patients were analyzed before treatment with CGRP monoclonal antibodies (baseline), after 12 months of treatment, and following a treatment break between November 2018 and December 2020 in the West German Headache Centre, University Hospital Essen, Germany. Monthly migraine days (MMD), monthly headache days (MHD), and days of acute medication intake (AMD) were assessed.

RESULTS

Complete clinical data from 46 migraine patients (14 episodic migraine (EM), 32 chronic migraine (CM) patients) treated with erenumab (n = 40), galcanezumab (n = 4), and fremanezumab (n = 2) were analyzed. The mean number of MMDs among EM and CM patients after 12 months of CGRP antibody treatment increased during the treatment break by 5.18 (SE 0.92, p < .001) and 5.06 (SE 1.22, p = .003) days, respectively. There was an increased intake of acute medications among episodic (4.72, SE 0.87, p = .004) and chronic migraine patients (3.01, SE 1.08, p = .013) during treatment break. Eighty-three percent of patients (n = 38) were dissatisfied with the mandatory treatment break. All patients continued with a CGRP (pathway) monoclonal antibody after the mandatory treatment break.

CONCLUSION

A mandatory break in CGRP (pathway) monoclonal antibody therapy had a negative short-term impact on migraine patients.

Predictors of Sustained Response and Effects of Anti-CGRP Antibodies Discontinuation and Reinitiation in Resistant Chronic Migraine

BACKGROUND

Guidelines for migraine prophylaxis suggest stopping medication after 6-12 months to reevaluate treatment appropriateness. The Italian Medicines Agency (AIFA) set a mandatory regulation to stop anti-CGRP (calcitonin gene related protein) pathway monoclonal antibody (anti-CGRP mAbs) treatments for 3 months after 12-months of treatment. Herein, we assess the effects of discontinuation and retreatment of anti-CGRP mAbs in resistant chronic migraine patients, evaluating predictive factors of sustained response.

METHODS

A monocentric prospective cohort study, enrolling 44 severe (resistant to ≥3 preventive treatments) chronic migraine patients (all with medication-overuse), treated with erenumab (54.5%) or galcanezumab (45.5%) for 12-months, who discontinued treatment for three months and then restarted for one month.

RESULTS

Overall, patients reported an increasing deteriorating trend during the three months of discontinuation. Monthly migraine days (MMDs), number of analgesics, days with at least one analgesic used, a ≥50% response rate (reduction in MMDs), and MIDAS and HIT-6 total scores, remained lower than baseline values, but increased if compared to month-12 of treatment. All outcome measures decreased again during the month of retreatment. Patients who did not meet criteria for restarting treatment had lower MIDAS (p=0.03) and HIT-6 (p=0.01) scores at baseline and better outcome measures during discontinuation compared to patients who restarted treatment.

CONCLUSIONS

In most patients, the 3-month discontinuation of anti-CGRP mAbs resulted in progressive migraine deterioration that was rapidly reverted by retreatment. However, one-fourth of patients, who reported better quality of life indices before treatment, showed a sustained benefit during discontinuation and did not need retreatment.

Migraine evolution after the cessation of CGRP(-receptor) antibody prophylaxis: a prospective, longitudinal cohort study

BACKGROUND

National and international guidelines recommend stopping migraine prophylaxis with CGRP(-receptor) monoclonal antibodies after 6-12 months of successful therapy. In this study, we aimed to analyze the course of migraine for four months after the cessation of CGRP(-receptor) antibodies use.

METHODS

This longitudinal cohort study included patients with migraine who received a CGRP-(receptor) antibody for ≥8 months before treatment cessation. We analyzed headache data in the four-week period prior to mAb treatment initiation (baseline), in the month before the last mAb injection, in weeks 5-8 and 13-16 after last treatment. Primary endpoint of the study was the change of monthly migraine days from the month before last treatment to weeks 13-16. Secondary endpoints were changes in monthly headache days and monthly days with acute medication use.

RESULTS

A total of 62 patients equally distributed between prophylaxis with the CGRP-receptor antibody erenumab and the CGRP antibodies galcanezumab or fremanezumab participated in the study. Patients reported 8.2 ± 6.6 monthly migraine days in the month before last treatment. Monthly migraine days gradually increased to 10.3 ± 6.8 in weeks 5-8 (p = 0.001) and to 12.5 ± 6.6 in weeks 13-16 (p < 0.001) after drug cessation. Monthly migraine days in weeks 13-16 were not different from baseline values (-0.8 ± 5.4; p > 0.999). Monthly headache days and monthly days with acute medication use showed a similar pattern.

CONCLUSIONS

The cessation of CGRP(-receptor) antibodies migraine prophylaxis was associated with a significant increase of migraine frequency and acute medication intake over time.

Prognosis Following Discontinuation of OnabotulinumA Therapy in "Super-responding" Chronic Migraine Patients

OBJECTIVE

To determine whether the successful treatment of chronic migraine (CM) with onabotulinumA (BotoxA) may be followed by a continued respite from headache once therapy has been discontinued.

BACKGROUND

The optimal duration of prophylactic therapy for migraine generally and for CM treated with BotoxA specifically is unknown.

METHODS

We conducted a prospective cohort study evaluating a series of patients with CM at a university-affiliated headache subspecialty clinic in Reno, Nevada, all of whom were treated according to a uniform protocol involving serial injections of BotoxA. We followed all positively responding patients who met our stopping rule for a minimum of 6 months after discontinuation of BotoxA, and we assessed the incidence of clinical worsening in that group.

RESULTS

A total of 105/131 patients (80%) for whom complete follow-up was available reported no clinical worsening or need to resume prophylactic therapy over the 6 months following discontinuation of BotoxA therapy. Patients with pre-treatment baseline chronic daily headache (CDH) of greater than 6 months duration were more likely to report clinical deterioration within 6 months of stopping treatment, as compared to patients with CDH of less than 6 months. A greater number of BotoxA treatments required to achieve our stopping rule correlated with clinical deterioration within 6 months of stopping treatment.

CONCLUSIONS

In many CM patients who experience an especially positive response to serial BotoxA injection therapy, clinical improvement may be sustained for a period of at least 6 months following discontinuation of prophylactic therapy.

The Effectiveness of Acupuncture Combined with Tuina Therapy in Patients with Migraine

BACKGROUND

This study aimed to explore the effectiveness of acupuncture combined with tuina therapy in patients with migraine.

METHODS

A prospective, randomized controlled assessor-blind clinical trial was performed between January 2017 and May 2018, and 135 patients were assigned into acupuncture combined with tuina (A), acupuncture (B), and control (flunarizine hydrochloride) (C) groups, each with 45 patients. Treatments were performed for 12 weeks and a 4-week follow-up. Frequency of attacks, severity of pain, duration of migraine, associated symptoms, patient-reported outcome (PRO) scores, and frequency of analgesic consumption were assessed.

RESULTS

The total effective rate was 95.6, 88.9, and 75.6% for group A, B, and C, respectively, with a significant reduction in attack frequency, severity of pain, duration of migraine, and associated symptoms at post-treatment and follow-up compared to pre-treatment. The PRO scores and frequency of analgesic consumption were significantly improved (group A, p < 0.01; groups B and C, - p < 0.05). The differences in pre-/post-treatment and in pre-treatment/follow-up in groups A and B were significantly improved compared to group C (A vs. C, p < 0.01; B vs. C, A vs. B, p < 0.05). No significant adverse events occurred.

CONCLUSION

Acupuncture combined with tuina could significantly increase the therapeutic effect of acupuncture in migraine treatment.

Discovery and Development of Calcium Channel Blockers

In the mid 1960s, experimental work on molecules under screening as coronary dilators allowed the discovery of the mechanism of calcium entry blockade by drugs later named calcium channel blockers. This paper summarizes scientific research on these small molecules interacting directly with L-type voltage-operated calcium channels. It also reports on experimental approaches translated into understanding of their therapeutic actions. The importance of calcium in muscle contraction was discovered by Sidney Ringer who reported this fact in 1883. Interest in the intracellular role of calcium arose 60 years later out of Kamada (Japan) and Heibrunn (USA) experiments in the early 1940s. Studies on pharmacology of calcium function were initiated in the mid 1960s and their therapeutic applications globally occurred in the the 1980s. The first part of this report deals with basic pharmacology in the cardiovascular system particularly in isolated arteries. In the section entitled from calcium antagonists to calcium channel blockers, it is recalled that drugs of a series of diphenylpiperazines screened in vivo on coronary bed precontracted by angiotensin were initially named calcium antagonists on the basis of their effect in depolarized arteries contracted by calcium. Studies on arteries contracted by catecholamines showed that the vasorelaxation resulted from blockade of calcium entry. Radiochemical and electrophysiological studies performed with dihydropyridines allowed their cellular targets to be identified with L-type voltage-operated calcium channels. The modulated receptor theory helped the understanding of their variation in affinity dependent on arterial cell membrane potential and promoted the terminology calcium channel blocker (CCB) of which the various chemical families are introduced in the paper. In the section entitled tissue selectivity of CCBs, it is shown that characteristics of the drug, properties of the tissue, and of the stimuli are important factors of their action. The high sensitivity of hypertensive animals is explained by the partial depolarization of their arteries. It is noted that they are arteriolar dilators and that they cannot be simply considered as vasodilators. The second part of this report provides key information about clinical usefulness of CCBs. A section is devoted to the controversy on their safety closed by the Allhat trial (2002). Sections are dedicated to their effect in cardiac ischemia, in cardiac arrhythmias, in atherosclerosis, in hypertension, and its complications. CCBs appear as the most commonly used for the treatment of cardiovascular diseases. As far as hypertension is concerned, globally the prevalence in adults aged 25 years and over was around 40% in 2008. Usefulness of CCBs is discussed on the basis of large clinical trials. At therapeutic dosage, they reduce the elevated blood pressure of hypertensive patients but don't change blood pressure of normotensive subjects, as was observed in animals. Those active on both L- and T-type channels are efficient in nephropathy. Alteration of cognitive function is a complication of hypertension recognized nowadays as eventually leading to dementia. This question is discussed together with the efficacy of CCBs in cognitive pathology. In the section entitled beyond the cardiovascular system, CCBs actions in migraine, neuropathic pain, and subarachnoid hemorrhage are reported. The final conclusions refer to long-term effects discovered in experimental animals that have not yet been clearly reported as being important in human pharmacotherapy.

Recurrent extracranial carotid artery vasospasms: report of 2 cases

BACKGROUND AND PURPOSE

Spontaneous vasospasms of the submandibular internal carotid arteries are rarely observed. They are a highly dynamic process, recur frequently, and can be detected by serial ultrasound examinations.

SUMMARY OF CASES

We present 2 cases of recurrent extracranial vasospasms of the internal carotid artery as a cause of stroke. In both cases, arterial dissection was initially suspected, but no intramural hematoma was detected on magnetic resonance imaging. Duplex sonography demonstrated recurrent high-grade stenoses of both internal carotid arteries that resolved spontaneously within hours to days. The vasospasms were treated with calcium antagonists and in 1 patient with oral corticoids.

CONCLUSIONS

Extracranial vasospasms as a cause of stroke might be underestimated. Vasospasms of the internal carotid arteries should be considered in patients with recurring ischemic events in the absence of any other explanation. Antiphlogistic treatment in combination with calcium antagonists might be effective to reduce the frequency of vasospasms.

An analysis of the "carry-over effect" following successful short-term treatment of transformed migraine with divalproex sodium

OBJECTIVE

To determine whether successful short-term prophylactic treatment of transformed migraine may be followed by a continued respite from headaches once the treatment has been discontinued ("carry-over effect").

BACKGROUND

The optimal duration of prophylactic treatment for pervasive headache and for migraine, in particular, is unknown.

METHODS

We prospectively evaluated a series of patients with transformed migraine, all of whom were managed according to a uniform treatment protocol involving prophylactic therapy with divalproex sodium for a period not exceeding 12 weeks. All patients reporting a positive treatment response were followed for at least 2 months after the discontinuation of divalproex sodium, and the incidence of the carry-over effect in that group was assessed.

RESULTS

A short-term carry-over effect occurred in 12 (60%) of 20 patients, but more sustained relief occurred in only 8 (40%).

CONCLUSIONS

The successful short-term treatment of transformed migraine with divalproex sodium will often produce a short-term carry-over effect, but this response will be sustained only in a minority of patients.

Evidence based migraine prophylactic drug therapy

Prophylactic drug therapy is a major component of overall migraine management. However, because we do not know how currently used prophylactic drugs exert their beneficial effects in migraine, their use is based primarily on clinical trials. In general, prophylactic drugs are indicated when patients have three or more attacks a month and symptomatic medication use alone is not satisfactory. The choice of drug must be individualized, and is influenced by contraindications, potential side effects, the need to treat associated symptoms like tension-type headache and insomnia, and drug cost. Whether an individual patient will respond to a given drug cannot be predicted, but there are varying degrees of scientific evidence supporting the use of each prophylactic drug in migraine. This evidence is best for metoprolol, divalproex, amitriptyline, atenolol, flunarizine and naproxen. Based on placebo-controlled crossover studies, it would appear that at least some prophylactic drugs exert the greater part of their prophylactic effects very quickly, and that these also disappear very quickly once the drug is stopped. This may not apply to all prophylactic drugs and more research is needed. More well designed clinical trials are needed to guide our use of migraine prophylactic drugs. Although clinical experience is useful, placebo responses and variations in the migraine tendency over time can make interpretation of this experience difficult. Major advances will likely only occur once the pathogenesis of migraine and the mode of action of the prophylactic drugs is better understood.

Flunarizine in migraine prophylaxis: predictive factors for a positive response

The efficacy of flunarizine in migraine prophylaxis is confirmed in both open and controlled trials. However, it is unknown what factors may influence a good response to prophylaxis with flunarizine. The aim of this study was to determine the possible predictive factors for therapeutic responsiveness to 3 months' treatment with flunarizine. One-hundred headache patients treated with flunarizine were evaluated. We considered "responders" those patients who recorded a reduction in migraine frequency of 75% after treatment. Statistical analysis revealed four factors which might influence therapeutic responsiveness in our patients. Positive factors were a family history (p<0.01) and high intensity of pain (p<0.01); negative factors were frequent attacks (p<0.01) and a history of analgesic abuse (p<0.001). Patients with no previous history of analgesic abuse, low frequency of attacks at baseline, higher levels of migraine pain, and positive family history constitute the prototype of flunarizine long-term treatment responders.