Efficacy and safety of erenumab (AMG334) in episodic migraine patients with prior preventive treatment failure: A subgroup analysis of a randomized, double-blind, placebo-controlled study

Comparing the Efficacy and Safety of Galcanezumab Versus Rimegepant for Prevention of Episodic Migraine: Results from a Randomized, Controlled Clinical Trial

INTRODUCTION

There have been no prior trials directly comparing the efficacy of different calcitonin gene-related peptide (CGRP) antagonists for migraine prevention. Reported are the results from the first head-to-head study of two CGRP antagonists, galcanezumab (monoclonal antibody) versus rimegepant (gepant), for the prevention of episodic migraine.

METHODS

In this 3-month, double-blind, double-dummy study, participants were randomized (1:1) to subcutaneous (SC) galcanezumab 120 mg per month (after a 240 mg loading dose) and a placebo oral disintegrating tablet (ODT) every other day (q.o.d.) or to rimegepant 75 mg ODT q.o.d. and a monthly SC placebo. The primary endpoint was the proportion of participants with a ≥ 50% reduction in migraine headache days per month from baseline across the 3-month double-blind treatment period. Key secondary endpoints were overall mean change from baseline in: migraine headache days per month across 3 months and at month 3, 2, and 1; migraine headache days per month with acute migraine medication use; Migraine-Specific Quality of Life Questionnaire Role Function-Restrictive domain score at month 3; and a ≥ 75% and 100% reduction from baseline in migraine headache days per month across 3 months.

RESULTS

Of 580 randomized participants (galcanezumab: 287, rimegepant: 293; mean age: 42 years), 83% were female and 81% Caucasian. Galcanezumab was not superior to rimegepant in achieving a ≥ 50% reduction from baseline in migraine headache days per month (62% versus 61% respectively; P = 0.70). Given the pre-specified multiple testing procedure, key secondary endpoints cannot be considered statistically significant. Overall, treatment-emergent adverse events were reported by 21% of participants, with no significant differences between study intervention groups.

CONCLUSIONS

Galcanezumab was not superior to rimegepant for the primary endpoint; however, both interventions demonstrated efficacy as preventive treatments in participants with episodic migraine. The efficacy and safety profiles observed in galcanezumab-treated participants were consistent with previous studies.

TRIAL REGISTRATION

ClinTrials.gov-NCT05127486 (I5Q-MC-CGBD).

Double-blind, randomized, placebo-controlled study to evaluate erenumab-specific central effects: an fMRI study

OBJECTIVE

Given the findings of central effects of erenumab in the literature, we aimed to conduct a rigorous placebo-controlled, double-blind, randomized study to elucidate whether the observed changes are directly attributable to the drug.

METHODS

We recruited 44 patients with migraine, randomly assigning them to either the erenumab 70 mg or the placebo group. 40 patients underwent fMRI scanning using a trigeminal nociceptive paradigm both, pre- and four weeks post-treatment. Participants kept a headache diary throughout the whole study period of two months in total. A clinical response was defined as a ≥30% reduction in headache frequency at follow-up. Details of this study have been preregistered in the open science framework: https://osf.io/ygf3t .

RESULTS

Seven participants of the verum group (n=33.33%) and 4 of the placebo group (21.05%) experienced improvements in migraine activity, characterized by a minimum of 30% reduction in monthly headache frequency compared to baseline. The imaging data show an interaction between the verum medication and the response. Whilst numbers were too small for individual analyses (Verum vs. Placebo and Responder vs. Non-Responder), the variance-weighted analysis (Verum vs Placebo, scan before vs after weighted for response) revealed specific decrease in thalamic, opercular and putamen activity.

INTERPRETATION

The central effects of erenumab could be reproduced in a placebo randomized design, further confirming its central role in migraine modulation. The mechanism, whether direct or secondary to peripheral mode of action, needs further exploration. It is important to note that the response rate to erenumab 70mg in this study was not as substantial as anticipated in 2019, when this study was planned. This resulted in a too small sample size for a subgroup analysis based on the responder status was associated with both the verum drug and the relative reduction in headache days.

Placebo and nocebo in the treatment of migraine: How much does real world effectiveness depend on contextual effects?

PURPOSE

Treatments in medicine impact individuals beyond their intended effects, due to phenomena such as the placebo and nocebo effects. The placebo effect arises from the positive expectation of a treatment being beneficial, while the nocebo effect stems from the negative expectation of a treatment causing harm. Both in real-world practice and clinical trials, treatments can lead to outcomes unrelated to their intended mechanism of action, which we categorize as placebo and nocebo responses. These responses, combined with the inherent fluctuation in a condition's natural progression, regression to the mean, and random comorbidities, make up a significant part of the therapeutic experience. Particularly in pain management, placebo and nocebo effects play a substantial role. By addressing modifiable contextual factors such as patient expectations, lifestyle choices, and the therapeutic relationship, healthcare providers can enhance the effectiveness of migraine treatments, paving the way for a more comprehensive, individualized approach to patient care. We must also consider non-modifiable factors like personal experiences, beliefs, and information from social media and the internet.

CONCLUSION

This review offers a summary of our current understanding of the placebo and nocebo effects in migraine management.

Impact of a reimbursement policy change on treatment with erenumab in migraine - a real-world experience from Germany

BACKGROUND

Monoclonal antibodies (mAbs) targeting the Calcitonin Gene-Related Peptide (CGRP) pathway are safe and effective treatments for migraine prevention. However, the high cost of these novel therapies has led to reimbursement policies requiring patients to try multiple traditional preventives before access. In Germany, a recent change in insurance policy significantly expanded coverage for the CGRP receptor mAb erenumab, enabling migraine patients who failed just one prior prophylactic medication to receive this mAb. Here, we compare the clinical response to treatment with erenumab in migraine patients treated using the old and new coverage policy.

METHODS

In this retrospective cohort study, we included CGRP-mAb naïve patients with episodic or chronic migraine, who started erenumab at our headache center according to either the old or the new insurance policy and received at least 3 consecutive injections. Headache diaries and electronic documentation were used to evaluate reductions in monthly headache and migraine days (MHD and MMD) and ≥ 50% and ≥ 30% responder rates at month 3 (weeks 9-12) of treatment.

RESULTS

We included 146 patients who received erenumab according to the old policy and 63 patients that were treated using the new policy. At weeks 9-12 of treatment, 37.7% of the old policy group had a 50% or greater reduction in MHD, compared to 63.5% of the new policy group (P < 0.001). Mean reduction in MHD was 5.02 days (SD = 5.46) and 6.67 days (SD = 5.32, P = 0.045) in the old and new policy cohort, respectively. After propensity score matching, the marginal effect of the new policy on treatment outcome was 2.29 days (standard error, SE: 0.715, P = 0.001) more reduction in MHD, and 30.1% (SE: 10.6%, P = 0.005) increase in ≥ 50% response rate for MHD.

CONCLUSIONS

Starting erenumab earlier in the course of migraine progression in a real-world setting may lead to a better response than starting after multiple failed prophylactic attempts. Continually gathering real-world evidence may help policymakers in deciding how readily to cover CGRP-targeted therapies in migraine prevention.

Erenumab efficacy in migraine headache prophylaxis: A systematic review

OBJECTIVE

This systematic review aims to show the efficiency of Erenumab in the preventive therapy of episodic and chronic migraine, which is still under research.

BACKGROUND

Migraine is a chronic neurovascular disorder that causes disability and a social burden. There are various medications used for migraine prevention regimens, most of which have unwanted side effects and aren't often quite effective. Erenumab is a monoclonal antibody that targets calcitonin gene-related peptide receptors and was recently approved by the Food and Drug Administration for migraine prevention.

METHODS

For this systematic review, we searched through Scopus and PubMed databases using "Erenumab" or "AMG 334" and "migraine" as keywords, and all the studies from 2016 to March 18, 2022, were included. Original English articles assessing any outcomes referring to the efficacy of Erenumab in migraine headache treatment were included in this study.

RESULTS

We found 53 out of 605 papers eligible to be investigated. Erenumab in both dosages of 70 mg and 140 mg could decrease the mean of monthly migraine days and monthly acute migraine-specific medication days. Erenumab also has a higher rate of ≥ 50 %, ≥ 75 %, and 100 % reduction in monthly migraine days from the baseline in different regions. The efficacy of Erenumab was initiated in the first week of administration and sustained throughout and after treatment. Erenumab was also potent in the treatment of migraine with allodynia, aura, prior preventive therapy failure, medication overuse headache, and menstrual migraine. Erenumab also had favorable outcomes in combination therapy with other preventive drugs like Onabotulinumtoxin-A.

CONCLUSION

Erenumab had remarkable efficacy in the short and long-term treatment of episodic and chronic migraine, notably the patients with difficult-to-treat migraine headaches.

An observational study on monoclonal antibodies against calcitonin-gene-related peptide and its receptor

BACKGROUND AND PURPOSE

Based on their pharmacological target, two classes of calcitonin-gene-related peptide (CGRP) monoclonal antibodies (mAbs) have been identified: antibodies against the CGRP ligand-galcanezumab, fremanezumab, eptinezumab-and antibodies against the CGRP receptor (CGRP-R), erenumab. The aim of the present study was to compare anti-CGRP versus anti-CGRP-R mAbs in patients with high frequency episodic and chronic migraine.

METHODS

All patients on monthly treatment with anti-CGRP mAbs with an available 6 months' follow-up at January 2022 were included. Data on efficacy outcome were collected following one (T1), three (T3) and six (T6) months of treatment, and included monthly headache/migraine days, the Migraine Disability Assessment Scale (MIDAS) and Headache Impact Test 6 (HIT-6) scores, pain intensity, analgesics consumption and response rates (>50% headache days reduction compared to baseline).

RESULTS

In all, 152 patients were enrolled, of whom 68 were in treatment with anti-CGRP mAbs (49 galcanezumab, 19 fremanezumab) and 84 with the anti-CGRP-R (erenumab). MIDAS scores were significantly lower in the anti-CGRP group at T1 and T3 (respectively p < 0.02 and p < 0.03) as well as the number of mean migraine days at T3 (p < 0.01). At T3 and T6 outcome measures were comparable, although a significantly higher percentage of super-responders was found in the anti-CGRP group (respectively p < 0.04 and p < 0.05), with a similar overall percentage of responders.

CONCLUSIONS

The present study on a real-world sample confirms the beneficial effect of both anti-CGRP and anti-CGRP-R mAbs, with a more favorable outcome for anti-CGRP antibodies.

Meta-regression to explain the placebo effects in clinical trials of anti-CGRP monoclonal antibodies for migraine prevention

Background: Commonly used methods of comparison (e.g. network meta-analyses) require common comparator(s) across trials, such as placebo in placebo-controlled trials. Recent literature indicates that route of administration differences across placebo arms of clinical trials in pain disorders may contribute to differences in placebo effect.Methods: We conducted a meta-regression on placebo data from pivotal clinical trials of anti-calcitonin gene-related peptide (anti-CGRP) monoclonal antibodies for migraine prevention to quantify the impact of route of administration, migraine type (episodic/chronic), and number of prior treatment failures on placebo reduction in monthly migraine days (MMDs) across weeks 1-12 of treatment. A systematic literature review of Embase, MEDLINE, the Cochrane Library, and grey literature conducted in June 2021 identified 14 relevant, randomized placebo-controlled trials for analysis.Results: After testing models with different covariates, a meta-regression was fitted to the extracted placebo data with the covariates of route of administration, migraine type, and proportion of patients with ≥2 prior preventive treatment failures. An intravenous route of administration for the placebo arm was a predictor for higher MMD reduction. Predictors of lower MMD reduction were migraine type (episodic migraine) and a higher proportion of patients having ≥2 failed preventive treatments.Conclusions: The efficacy of intravenous anti-CGRP monoclonal antibodies are likely underestimated, and differences in the route of administration of placebo may necessitate use of alternative methods that do not assume the presence of a common comparator when comparing anti-CGRP monoclonal antibodies in migraine prevention. Further research into the contextual effects of the placebo effect is warranted.

Monoclonal Antibodies against Calcitonin Gene-Related Peptide for Migraine Prophylaxis: A Systematic Review of Real-World Data

OBJECTIVE

To perform a systematic review of real-world outcomes for anti-CGRP-mAbs.

METHODS

Following the PRISMA guidelines, we searched PubMed for real-world data of erenumab, galcanezumab, fremanezumab, or eptinezumab in patients with migraines.

RESULTS

We identified 134 publications (89 retrospective), comprising 10 pharmaco-epidemiologic and 83 clinic-based studies, 38 case reports, and 3 other articles. None of the clinic-based studies provided follow-up data over more than one year in more than 200 patients. Findings suggest that there are reductions in health insurance claims and days with sick-leave as well as better treatment adherence with anti-CGRP-mAbs. Effectiveness, reported in 77 clinic-based studies, was comparable to randomized controlled trials. A treatment pause was associated with an increase in migraine frequency, and switching to another antibody resulted in a better response in some of the patients. Adverse events and safety issues were addressed in 86 papers, including 24 single case reports.

CONCLUSION

Real-world data on anti-CGRP-mAbs are limited by retrospective data collection, small patient numbers, and short follow-up periods. The majority of papers seem to support good effectiveness and tolerability of anti-CGRP-mAbs in the real-world setting. There is an unmet need for large prospective real-world studies providing long-term follow-ups of patients treated with anti-CGRP-mAbs.

Erenumab versus topiramate: post hoc efficacy analysis from the HER-MES study

OBJECTIVE

HER-MES was the first head-to-head, phase 4 trial to assess the tolerability and effectiveness of erenumab against standard of care treatment (topiramate). This post hoc analysis compared the efficacy of erenumab with topiramate in patients who completed the trial on study medication.

METHODS

Post hoc sensitivity analysis was performed using the full analysis set. Outcomes assessed included the proportion of patients with a ≥50% reduction in monthly migraine days (MMD) from baseline (50% responder rate), over the last 3 months (months 4, 5, and 6) of the double-blind treatment phase (DBTP), the 50% responder rate during the first month of the DBTP, and change from baseline in MMD during the DBTP. Multiple imputation was done for efficacy values of patients who discontinued study treatment.

RESULTS

Patients (N = 777) were randomly assigned (1:1) to either 70 or 140 mg/month erenumab (N = 389) or 50-100 mg/day topiramate (N = 388). Of these, 334 patients (85.9%) receiving erenumab, and 231 patients (59.5%) receiving topiramate completed the DBTP on study medication. Patients on study medication until the end of the DBTP received a mean dose of 119 mg/month for erenumab and 92 mg/day for topiramate. At month 1, a significantly greater proportion of patients receiving erenumab (39.2%) reported ≥50% reduction in MMD from baseline compared with those receiving topiramate (24.0%; p < 0.001). In the last 3 months, a significantly larger proportion of patients receiving erenumab (60.3%) achieved ≥50% reduction in MMD from baseline compared with those receiving topiramate (43.3%; p < 0.001). Patients receiving erenumab demonstrated significantly greater reductions in MMD during the last 3 months from baseline versus those receiving topiramate (- 6.13 vs - 4.90; 95% CI: - 1.87 to - 0.61; p < 0.001).

CONCLUSIONS

This post hoc analysis demonstrated significantly superior efficacy of erenumab versus topiramate in achieving a ≥50% reduction in MMD with an early onset of efficacy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03828539 .

Efficacy and safety of monoclonal antibody against calcitonin gene-related peptide or its receptor for migraine patients with prior preventive treatment failure: a network meta-analysis

Objective

The relative effects of monoclonal antibody against calcitonin gene-related peptide (CGRP) or its receptor for adult migraine patients with prior treatment failure remains uncertain. Therefore, this study systematically assessed the comparative effectiveness of different CGRP binding monoclonal antibodies (mAbs) for these patients.

Methods

Several online databases including Ovid MEDILNE, Ovid EMBASE, Cochrane Library, and ClinicalTrials.gov were systematically searched from inception to June 15, 2022. We included randomized clinical trials (RCT) of adult migraine patients with previous treatment failure that assessed any CGRP monoclonal antibody. The primary efficacy outcome was change in monthly migraine days (MMDs), and the primary safety outcome was treatment-emergent adverse events (TEAEs).

Results

Overall, seven studies totaling 3, 052 patients were included. Three-node analysis showed that CGRP mAbs was superior to CGRP receptor mAbs in reducing MMDs (MD: -1.55, 95% CrI: − 2.43 to − 0.44) and improving at least 50% response rates (RR: 1.52, 95% CrI: 1.04 to 2.21). Nine-node analysis showed galcanezumab 240 mg ranked first in reducing MMDs (MD -4.40, 95% CrI − 7.60 to − 1.19) and improving 50% response rates (RR: 4.18, 95% CrI: 2.63 to 6.67). Moreover, treatment with fremanezumab or eptinezumab 300 mg provides a significant advantage over erenumab 140 mg regarding an improved response rate of at least 50%. The analysis did not show difference in incidences of TEAEs and serious adverse events in any of the comparisons.

Conclusions

It appears that CGRP mAbs, especially galcanezumab 240 mg, monthly fremanezumab, and eptinezumab 300 mg, seem to be the best choice for the treatment of migraine patients with previous treatment failures. This finding also calls for future research that examine the associations between these medications in migraine therapy among the same patient group to testify the present findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01472-2.

Real-world experience of erenumab in patients with chronic or episodic migraine in the UAE

Background

Erenumab is a fully human monoclonal antibody and a highly potent, first-in-class calcitonin gene-related peptide receptor inhibitor approved for migraine prevention in adults. Randomised, placebo-controlled trials show that erenumab treatment results in clinically meaningful responses, including significant reductions in monthly migraine days. Real-world evidence of the effectiveness of erenumab in patients with migraine is accruing, but gaps remain, and findings may vary according to region. We evaluated the usage patterns and effectiveness of erenumab in real-world settings in patients with migraine in the United Arab Emirates (UAE).

Methods

This retrospective, observational real-world study enrolled patients ≥ 18 years with migraine who were prescribed erenumab in the UAE. Data were collected at baseline and Months 1, 3 and 6. The primary study objective was to characterise usage patterns of erenumab in patients with chronic migraine (CM) or episodic migraine (EM) in real-world settings in the UAE.

Results

Of the 166 patients, 124 (74.7%) were females. The mean (standard deviation) age at migraine onset was 29 (7.93) years. Seventy-one patients (42.8%) had CM and 95 (57.2%) had EM.

In the overall population, the mean monthly headache/migraine days (MHD) at baseline was 15.7 (8.45) and mean change from baseline was − 8.2 (8.83) at Month 1, − 11.0 (9.15) at Month 3 and − 11.3 (8.90) at Month 6. The mean change from baseline in monthly acute migraine-specific medication days (MSMD) was − 9.0 (8.07) at Month 1, − 9.7 (8.73) at Month 3 and − 10.7 (8.95) at Month 6. At all time points, most patients achieved at least 50% reduction in MHD (80%–91%) and MSMD (84%–94%).

Similar reductions in MHD and MSMD and clinical benefit in CM or EM were seen with erenumab monotherapy or erenumab add-on therapy, with or without dose escalation and for treatment naïve or ≥ 1 previous preventive treatment failures, with additional clinical benefit in the erenumab add-on therapy and dose escalation to 140 mg subgroups.

Conclusion

In this real-world study on erenumab use in the UAE, patients prescribed erenumab achieved clinically meaningful reductions in MHD and MSMD at all assessed time points. Erenumab was well tolerated with no new safety events.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02710-5.

Advances in pharmacotherapy for the prophylactic treatment of resistant and refractory migraine

INTRODUCTION

Refractory migraine is associated with low quality of life and great socioeconomic burden. Despite high need for effective, tolerable preventive therapies, there has been little research on potential therapeutic options. Monoclonal antibodies (mAbs) against Calcitonin Gene-Related Peptide (CGRP) are the first preventive therapeutic approach for migraine based on the underlying pathophysiology.

AREAS COVERED

Following a brief introduction into the term 'refractory migraine,' the authors reviewavailable treatment options, focusing on current phase III trials of substances acting on the CGRP pathway.

EXPERT OPINION

No uniform definition for refractory migraine is available. The vast majority of proposals recommend treatment failure of 2-4 drug classes as a key diagnostic criterion. Phase III studies on CGRP-(receptor) mAbs demonstrated excellent efficacy and tolerability in patients with chronic and episodic migraine including subjects with multiple unsuccessful conventional therapy attempts. However, more comparator trials showing superiority of mAbs versus oral preventatives, such as the HER-MEs study are needed. In summary, with the CGRP antibodies, a group of drugs has entered the market which will most likely not only significantly improve the quality of life of many individual migraine patients but could also reduce indirect health-care costs associated with migraine by reducing recurrent medical consultations.

Assessment and Characteristics of Erenumab therapy on migraine management

Background

Methods

Results

Conclusion

The monoclonal CGRP-receptor blocking antibody erenumab has different effects on brainstem and cortical sensory-evoked responses

Objectives

It is unclear whether the electrophysiological effects of erenumab, a monoclonal antibody against the calcitonin gene-related peptide receptor, occur only at the periphery of the trigeminal system or centrally and at the cortical level.

Methods

We prospectively enrolled 20 patients with migraine who had failed at least two preventative treatments. We measured the nociceptive blink reflex and non-noxious somatosensory evoked potentials in all participants. The area under the curve and habituation of the second polysynaptic nociceptive blink reflex component (R2) as well as the amplitude and habituation of somatosensory evoked potentials N20-P25 were measured. Electrophysiological data were collected at baseline (T0), 28 days (T1), and 56 days (T2) before each injection of erenumab (70 mg).

Results

Erenumab reduced the patients’ mean monthly headache days, headache intensity, and acute medication intake considerably at T1 and T2 (all p < 0.05). The nociceptive blink reflex area under the curve was considerably lower at T1 and T2 than at baseline without changing the habituation slope. At T2, there was a significant increase in the delayed somatosensory evoked potentials amplitude reduction (habituation) but not in the initial cortical activation.

Conclusion

Our findings showed that erenumab, in addition to its well-known peripheral effects, can induce central effects earlier in the brainstem and later in the cortex. We cannot rule out whether these results are due to a direct effect of erenumab on the central nervous system or an indirect effect secondary to peripheral drug modulation.

Migraine Prevention with Erenumab: Focus on Patient Selection, Perspectives and Outcomes

Erenumab is a monoclonal antibody targeting the calcitonin gene-related peptide (CGRP) receptor suitable for episodic and chronic migraine prevention. Randomized clinical trials proved the superiority of erenumab to placebo in a strictly selected population, while real-world studies confirmed treatment efficacy in more severe forms of disease – most patients suffered from chronic migraine with medication overuse headache, had prior treatment failures, and long disease duration. According to guidelines, anti-CGRP pathway monoclonal antibodies should be reserved to patients who failed or have contraindication to several classes of preventive treatments. However, their ease of use, tolerability and efficacy make these monoclonal antibodies ideally suitable for most patients with migraine; cost-effectiveness needs to be considered when looking at expanding current prescription criteria. Also, data from open label extensions of randomized control trials confirmed sustained benefits of prolonged treatment up to 5 consecutive years without significant risk of adverse events. Further studies will provide insights on optimal treatment duration to achieve migraine remission and predictors of treatment response. In the present work, we aimed at reviewing design and results of the main studies on erenumab and discussing treatment use in the current migraine prevention scenario; we also summarized the main ongoing research projects and provided clinical perspectives for the future.

Two-year efficacy and safety of erenumab in participants with episodic migraine and 2-4 prior preventive treatment failures: results from the LIBERTY study

OBJECTIVE

To evaluate individual and group long-term efficacy and safety of erenumab in individuals with episodic migraine (EM) for whom 2-4 prior preventatives had failed.

METHODS

Participants completing the 12-week double-blind treatment phase (DBTP) of the LIBERTY study could continue into an open-label extension phase (OLEP) receiving erenumab 140 mg monthly for up to 3 years. Main outcomes assessed at week 112 were: ≥50%, ≥75% and 100% reduction in monthly migraine days (MMD) as group responder rate and individual responder rates, MMD change from baseline, safety and tolerability.

RESULTS

Overall 240/246 (97.6%) entered the OLEP (118 continuing erenumab, 122 switching from placebo). In total 181/240 (75.4%) reached 112 weeks, 24.6% discontinued, mainly due to lack of efficacy (44.0%), participant decision (37.0%) and adverse events (AEs; 12.0%). The ≥50% responder rate was 57.2% (99/173) at 112 weeks. Of ≥50% responders at the end of the DBTP, 36/52 (69.2%) remained responders at ≥50% and 22/52 (42.3%) at >80% of visits. Of the non-responders at the end of the DBTP, 60/185 (32.4%) converted to ≥50% responders in at least half the visits and 24/185 (13.0%) converted to ≥50% responders in >80% of visits. Change from baseline at 112 weeks in mean (SD) MMD was -4.2 (5.0) days. Common AEs (≥10%) were nasopharyngitis, influenza and back pain.

CONCLUSIONS

Efficacy was sustained over 112 weeks in individuals with difficult-to-treat EM for whom 2-4 prior migraine preventives had failed. Erenumab treatment was safe and well tolerated, in-line with previous studies.

TRIAL REGISTRATION NUMBER

NCT03096834.

Real-World Evidence for Control of Chronic Migraine Patients Receiving CGRP Monoclonal Antibody Therapy Added to OnabotulinumtoxinA: A Retrospective Chart Review

INTRODUCTION

Combination use of onabotulinumtoxinA and calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) has the potential to be more effective than either therapy alone for migraine prevention.

METHODS

This retrospective, longitudinal chart review included adults with chronic migraine treated at one clinical site with ≥ 2 consecutive cycles of onabotulinumtoxinA and ≥ 1 month of subsequent combination treatment with CGRP mAbs. Charts at time of mAb prescription (baseline) and up to four visits ~ 3, 6, 9, and 12 months post-baseline were reviewed for safety, tolerability, and outcome measures (monthly headache days [MHDs], headache intensity, and migraine-related disability [MIDAS]).

RESULTS

Of 300 charts reviewed, 257 patients met eligibility criteria (mean age: 50 years; 82% women). Average headache frequency was 21.5 MHDs before initiation of onabotulinumtoxinA and 12.1 MHDs before adding CGRP mAb therapy. Prescribed mAbs were erenumab (78%), fremanezumab (6%), and galcanezumab (16%). Over the entire study, patients discontinued CGRP mAb more frequently than onabotulinumtoxinA (23 vs. 3%). Adverse events occurred in 28% of patients, most commonly constipation (9%). Compared with onabotulinumtoxinA alone (baseline), MHDs decreased significantly at all visits (mean decrease: 3.5-4.0 MHDs over ~ 6-12 months of combination treatment); 45.1% of patients had clinically meaningful improvement in migraine-related disability (≥ 5-point reduction in MIDAS score) after ~ 6 months.

CONCLUSIONS

In this real-world study, combination treatment with onabotulinumtoxinA and CGRP mAbs was well tolerated, with no new safety signals identified, and was associated with additional clinically meaningful benefits. More real-world and controlled trials should be considered to further assess safety and potential benefits of combination treatment. Video abstract: Real-world data suggests that CGRP inhibitors improve onabotulinumtoxinA efficacy for chronic migraine (MP4 20,067 kb).

Hypervigilance, Allostatic Load, and Migraine Prevention: Antibodies to CGRP or Receptor

Migraine involves brain hypersensitivity with episodic dysfunction triggered by behavioral or physiological stressors. During an acute migraine attack the trigeminal nerve is activated (peripheral sensitization). This leads to central sensitization with activation of the central pathways including the trigeminal nucleus caudalis, the trigemino-thalamic tract, and the thalamus. In episodic migraine the sensitization process ends with the individual act, but with chronic migraine central sensitization may continue interictally. Increased allostatic load, the consequence of chronic, repeated exposure to stressors, leads to central sensitization, lowering the threshold for future neuronal activation (hypervigilance). Ostensibly innocuous stressors are then sufficient to trigger an attack. Medications that reduce sensitization may help patients who are hypervigilant and help to balance allostatic load. Acute treatments and drugs for migraine prevention have traditionally been used to reduce attack duration and frequency. However, since many patients do not fully respond, an unmet treatment need remains. Calcitonin gene-related peptide (CGRP) is a vasoactive neuropeptide involved in nociception and in the sensitization of peripheral and central neurons of the trigeminovascular system, which is implicated in migraine pathophysiology. Elevated CGRP levels are associated with dysregulated signaling in the trigeminovascular system, leading to maladaptive responses to behavioral or physiological stressors. CGRP may, therefore, play a key role in the underlying pathophysiology of migraine. Increased understanding of the role of CGRP in migraine led to the development of small-molecule antagonists (gepants) and monoclonal antibodies (mAbs) that target either CGRP or the receptor (CGRP-R) to restore homeostasis, reducing the frequency, duration, and severity of attacks. In clinical trials, US Food and Drug Administration-approved anti-CGRP-R/CGRP mAbs were well tolerated and effective as preventive migraine treatments. Here, we explore the role of CGRP in migraine pathophysiology and the use of gepants or mAbs to suppress CGRP-R signaling via inhibition of the CGRP ligand or receptor.

Efficacy and safety of erenumab in Japanese migraine patients with prior preventive treatment failure or concomitant preventive treatment: subgroup analyses of a phase 3, randomized trial

Background

These subgroup analyses of a Phase 3, randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of erenumab 70 mg in Japanese migraine patients with/without prior preventive treatment failure(s) (“failed-yes” and “failed-no” subgroups) and with/without concomitant preventive treatment (“concomitant preventive-yes” and “concomitant preventive-no” subgroups).

Methods

Overall, 261 patients were randomized; 130 and 131 patients to erenumab 70 mg and placebo, respectively. Subgroup analyses evaluated the change from baseline to Months 4–6 in mean monthly migraine days (MMD) (primary endpoint), achievement of a ≥50% reduction in mean MMD, and change from baseline in mean monthly acute migraine-specific medication (MSM) treatment days. Treatment-emergent adverse events were also evaluated.

Results

Of the 261 patients randomized, 117 (44.8%) and 92 (35.3%) patients were in the failed-yes and concomitant preventive-yes subgroups, respectively. Erenumab 70 mg demonstrated consistent efficacy across all subgroups, with greater reductions from baseline in mean MMD versus placebo at Months 4–6 (treatment difference versus placebo [95% CI], failed-yes: − 1.9 [− 3.3, − 0.4]; failed-no: − 1.4 [− 2.6, − 0.3]; concomitant preventive-yes: − 1.7 [− 3.3, 0.0]; concomitant preventive-no: − 1.6 [− 2.6, − 0.5]). Similar results were seen for achievement of ≥50% reduction in mean MMD and change from baseline in mean monthly acute MSM treatment days. The safety profile of erenumab 70 mg was similar across subgroups, and similar to placebo in each subgroup.

Conclusion

Erenumab was associated with clinically relevant improvements in all efficacy endpoints and was well tolerated across all subgroups of Japanese migraine patients with/without prior preventive treatment failure(s) and with/without concomitant preventive treatment.

Trial registration

Clinicaltrials.gov. NCT03812224. Registered January 23, 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01313-8.

Optimal dose of erenumab for preventive treatment of episodic migraine: a systematic review and meta-analysis

Background:

Erenumab is a novel monoclonal calcitonin gene-related peptide receptor antibody that is used for the preventive treatment of migraine.

Objectives:

This study aimed to evaluate the overall safety, efficacy, and dose-response relationship of erenumab in patients with episodic migraine and patients with prior migraine treatment failures.

Methods:

We searched randomized clinical trials on PUBMED, EMBASE database, and Cochrane Library database. A pair-wise meta-analysis and Bayesian network analysis were performed.

Results:

For efficacy outcomes, the network meta-analysis suggests that in comparison to erenumab 70 mg, participants who received erenumab 140 mg reported a significant decrease in monthly acute Migraine-Specific Medication Days (MSMD) and 50% increase in response rate, and erenumab was most likely to be ranked first for Monthly Migraine Days (MMD), MSMD, and 50% response rate. For safety outcomes, the network meta-analysis has found no significant difference between the 70 mg group and the 140 mg group measured by adverse events and serious adverse events. In the 140 mg erenumab group, a significant decreased in MMD and MSMD and 50% and 75% increased in response rate were reported in patients with ≥ 2 treatment failures compared to placebo. For safety outcomes, no significant difference was found between the 140 mg erenumab group and the placebo group.

Conclusion:

Erenumab was effective in patients with episodic migraine. A total of 140 mg erenumab was associated with better efficacy outcomes without any increased risk for developing adverse events compared to 70 mg erenumab. Furthermore, 140 mg erenumab was effective in patients with prior migraine treatment failures.

Reduction in acute migraine-specific and non-specific medication use in patients treated with erenumab: post-hoc analyses of episodic and chronic migraine clinical trials

Background

In patients with migraine, overuse of acute medication, including migraine-specific medication (MSM) such as triptans and ergots, can lead to adverse health outcomes, including development of medication overuse headache. Here, we examined the effect of erenumab on reducing acute medication use, in particular MSM, in patients with episodic migraine (EM) and chronic migraine (CM).

Methods

The current post-hoc analyses were based on data from the double-blind treatment phase (DBTP) of two erenumab studies, a pivotal EM (N = 955) and a pivotal CM (N = 667) trial, and their respective extensions. Patients were administered subcutaneous placebo or erenumab (70 or 140 mg) once monthly. Daily acute headache medication use (including MSM and non-MSM) was recorded using an electronic diary during a 4-week pretreatment baseline period until the end of the treatment period. Outcome measures included change in monthly acute headache medication days (HMD) in acute headache medication users at baseline, and changes in monthly MSM days (MSMD) in MSM users at baseline and non-MSMD in non-MSM users at baseline.

Results

In total, 60 and 78 % of patients (all acute headache medication users) with EM and CM used MSM at baseline, respectively. For acute headache medication users, the change in mean monthly acute HMD over Months 4, 5 and 6 compared with the pre-DBTP was 1.5, 2.5, and 3.0 for placebo, erenumab 70 mg and 140 mg, respectively for the EM study. The respective change in monthly MSMD in MSM users was 0.5, 2.1 and 2.8, and in monthly non-MSMD in non-MSM users was 2.3, 2.6, and 2.7. In the acute headache medication users at baseline, the change in monthly acute HMD at Month 3 compared with pre-DBTP was 3.4, 5.5, and 6.5 for placebo, erenumab 70 mg and 140 mg, respectively for the CM study. The respective change in monthly MSMD in MSM users was 2.1, 4.5, and 5.4, and in monthly non-MSMD in non-MSM users was 5.9, 6.4, and 6.6. Reductions in MSMD versus placebo were sustained in the extension periods of both studies. Erenumab was also associated with a higher proportion of MSM users achieving ≥ 50 %, ≥ 75 and 100 % reduction from baseline in monthly MSMD versus placebo in both EM and CM.

Conclusions

In both EM and CM, treatment with erenumab is associated with a significant and sustained reduction in the use of acute headache medication, in particular MSM.

Trial registrations

NCT02456740; NCT02066415; NCT02174861.

Role of Monoclonal Antibodies against Calcitonin Gene-Related Peptide (CGRP) in Episodic Migraine Prevention: Where Do We Stand Today?

Background

Medications targeting the calcitonin gene-related peptide (CGRP) pathway are exciting and novel therapeutic options in the treatment of migraine.

Objective

In this article, we have reviewed the role of these CGRP monoclonal antibodies in patients with episodic migraine.

Materials and Methods

We did an extensive literature search for all phase 2 and 3 studies involving CGRP monoclonal antibodies in episodic migraine.

Results

Erenumab, fremanezumab, galcanezumab, and eptinezumab have all undergone phase 3 trials and have been found to be effective for episodic and chronic migraine. They have the advantage of being targeted therapies for migraine with very favorable adverse effect profiles comparable to placebo. Importantly, they are effective in subgroups of patients who have failed previous preventive therapies.

Conclusion

Increasing use of these medications will certainly revolutionize the treatment and outlook for patients with migraine all over the world.

Emerging Targets for Migraine Treatment

Background

While understanding the pathophysiology of migraine has led to CGRP-based treatments, other potential targets have also been implicated in migraine.

Objectives

To catalog new promising targets for the treatment of migraine.

Methods

We completed a literature review focusing on 5HT_1F, PACAP, melatonin, and orexins.

Results

The 5HT_1F receptor agonist lasmiditan, following two positive randomized placebo-controlled trials, was FDA-approved for the acute treatment of migraine. PACAP-38 has shown analogous evidence to what was obtained for CGRP with its localization in key structures, provocation tests, and positive studies when antagonizing its receptor in animal models, although a PAC-1 receptor monoclonal antibody study was negative. Melatonin has undergone several randomized controlled trials showing a positive trend. Filorexant is the only dual orexin receptor antagonist, which was tested in humans with negative results.

Conclusions

Further and ongoing studies will determine the utility of these new therapies with lasmiditan and melatonin having demonstrated efficacy for the treatment of migraine.

Fremanezumab for the Preventive Treatment of Migraine: Subgroup Analysis by Number of Prior Preventive Treatments with Inadequate Response

OBJECTIVE

To evaluate the efficacy of monthly or quarterly fremanezumab in patients with chronic migraine or episodic migraine and documented inadequate response to 2, 3, or 4 classes of prior migraine preventive medications.

METHODS

This is an exploratory analysis of a randomized, double-blind, placebo-controlled, phase 3b trial for patients with chronic migraine or episodic migraine and inadequate response to 2 to 4 prior migraine preventive medication classes randomized (1:1:1) to fremanezumab (quarterly or monthly) or placebo. In this exploratory analysis, changes from baseline in the monthly average number of migraine days during 12 weeks of double-blind treatment and adverse events were evaluated for predefined subgroups of patients by number of prior preventive medication classes with inadequate response.

RESULTS

Overall, 414, 265, and 153 patients had inadequate response to 2, 3, and 4 preventive medication classes, respectively. Changes from baseline in monthly average migraine days during 12 weeks were significantly greater with fremanezumab compared with placebo for patients with documented inadequate response to 2 classes (least-squares mean difference vs placebo [95% confidence interval]: quarterly, -2.9 [-3.83, -1.98]; monthly, -3.7 [-4.63, -2.75]), 3 classes (quarterly, -3.3 [-4.65, -1.95]; monthly, -3.0 [-4.25, -1.66]), and 4 classes (quarterly, -5.3 [-7.38, -3.22]; monthly, -5.4 [-7.35, -3.48]) of migraine preventive medications (all p < 0.001). No significant treatment-by-subgroup interactions were observed for any outcome (p interaction > 0.20 for all). Adverse events were comparable for placebo and fremanezumab.

CONCLUSION

Significant improvements in efficacy were observed with fremanezumab compared with placebo, even in patients who had previously experienced inadequate response to 4 different classes of migraine preventive medications.ClinicalTrials.gov identifier: NCT03308968.

Effect of erenumab on functional outcomes in patients with episodic migraine in whom 2-4 preventives were not useful: results from the LIBERTY study

OBJECTIVE

To evaluate the effect of erenumab on patient-reported, functional outcomes in patients with episodic migraine (EM) in whom 2-4 preventives were not useful from the Phase 3b LIBERTY study.

METHODS

As previously reported, 246 patients with EM with 2-4 prior failed preventives were randomised 1:1 to subcutaneous erenumab 140 mg or placebo every 4 weeks for 12 weeks. This analysis evaluated Migraine Physical Function Impact Diary (MPFID), Headache Impact Test (HIT-6) and Work Productivity and Activity Impairment (WPAI) scores at Week 12. P values were nominal without multiplicity adjustment.

RESULTS

Erenumab significantly improved MPFID-Physical Impairment (PI) and Everyday Activities (EA) scores versus placebo (treatment difference (TD) (95% CI) MPFID-PI: -3.5 (-5.7 to -1.2) (p=0.003); MPFID-EA: -3.9 (-6.1 to -1.7)) (p<0.001) at 12 weeks. Patients on erenumab were more likely to have a ≥5-point reduction in MPFID score (OR vs placebo (95% CI) MPFID-EA: 2.1 (1.2 to 3.6); MPFID-PI: 2.5 (1.4 to 4.5)). A similar trend was observed for HIT-6 (TD: -3.0; p<0.001); significantly higher proportions of patients on erenumab reported a ≥5-point reduction (OR (95% CI): 2.4 (1.4 to 4.1)). In three out of four WPAI domains, erenumab showed improvement versus placebo.

CONCLUSION

At 12 weeks, erenumab was efficacious on functional outcomes in patients with EM in whom 2-4 preventives were not useful.

TRIAL REGISTRATION DETAILS

ClinicalTrials.gov identifier: NCT03096834.

Pituitary adenylate cyclase-activating polypeptide/vasoactive intestinal peptide (Part 2): biology and clinical importance in central nervous system and inflammatory disorders

PURPOSE OF REVIEW

To discuss recent advances of vasoactive intestinal peptide/pituitary adenylate cyclase-activating polypeptide (VIP/PACAP) receptors in the selected central nervous system (CNS) and inflammatory disorders.

RECENT FINDINGS

Recent studies provide evidence that PACAP plays an important role in a number of CNS disorders, particularly the pathogenesis of headaches (migraine, etc.) as well as posttraumatic stress disorder and drug/alcohol/smoking addiction. VIP has important therapeutic effects in a number of autoimmune/inflammatory disorder such as rheumatoid arthritis. In some cases, these insights have advanced to therapeutic trials.

SUMMARY

Recent insights from studies of VIP/PACAP and their receptors in both CNS disorders (migraine, posttraumatic stress disorder, addiction [drugs, alcohol, smoking]) and inflammatory disorders [such as rheumatoid arthritis] are suggesting new treatment approaches. The elucidation of the importance of VIP/PACAP system in these disorders combined recent development of specific drugs acting on this system (i.e., monoclonal VIP/PACAP antibodies) will likely lead to importance novel treatment approaches in these diseases.

Targets for migraine treatment: beyond calcitonin gene-related peptide

PURPOSE OF REVIEW

Despite the development of several medications for the acute and preventive treatment of migraine, there are still many patients in whom lack of efficacy, tolerability, interactions or contraindications make other options necessary. CGRP-based drugs have opened the door to a new era of migraine-targeted treatments. Beyond CGRP, there are other promising targets covered here.

RECENT FINDINGS

For the acute treatment of migraine, 5-HT1F receptor agonists, ditans, are now available. Unlike triptans, 5-HT1B/1D receptor agonists, cardiovascular disease is not a contraindication for the use of ditans. The first study on a monoclonal antibody targeting PAC1 receptor was negative, although this may not be the end for the pituitary adenylate cyclase-activating polypeptide (PACAP) pathway as a target.

SUMMARY

Following positive phase-III clinical trials, lasmiditan is the first ditan to be FDA-approved. PACAP has experimental evidence suggesting a role in migraine pathophysiology. As for CGRP, the presence of PACAP in key migraine structures along with positive provocative tests for both PACAP-38 and PACAP-27 indicate this pathway may still be a pharmacological target. Glutamate-based targets have long been considered in migraine. Two clinical trials with memantine, an NMDA-R antagonist, for the preventive treatment of migraine have now been published. The hypothalamus has also been implicated in migraine pathophysiology: the potential role of orexins in migraine is discussed. Acid-sensing ion channels, as well as amylin-blocking drugs, may also become migraine treatments in the future: more research is warranted.

The impact of anti-CGRP monoclonal antibodies in resistant migraine patients: a real-world evidence observational study

OBJECTIVE

To evaluate the frequency and headache-related impact response to monoclonal antibodies against calcitonin gene-related peptide (CGRP) in a clinical sample of refractory migraine patients.

METHODS

We included migraine patients with ≥ 8 headache days/month that had failed at least three preventive medications. Demographic, medical and migraine history were collected. Patients completed an electronic headache diary including headache days/month, migraine days/month, headache pain intensity (0-3 numerical scale), use of analgesics and completed Patient-Reported Outcome questionnaires at baseline and after 12 weeks. Patients were classified into ≥ 50%, ≥ 75% and 100% responders according to the improvement in frequency.

RESULTS

We included 155 patients (109 erenumab and 46 galcanezumab). After 12 weeks, headache frequency decreased - 9.1 headache days/month and - 8.5 migraine days/month from baseline. A 39.5% had a ≥ 50% headache days/month reduction and a 51.6% ≥ 50% migraine days/month reduction. In the ≥ 50% migraine days/month-responders group, frequency reduction was - 13,9 migraine days/month from baseline and showed clear improvements for all patient-reported outcomes. A 14.2% and 26.5% had a ≥ 75% response in headache and migraine days/month, respectively, and 11.0% showed a 100% migraine days/month reduction. Patients who were not on other preventive medications had less severe disability and higher ratio of migraine over headache days/month were more likely of being a ≥ 50% migraine days/month-responder. We did not record any severe adverse events, being the most common constipation (20.0%), fatigue (7.1%) and a transient increase in blood pressure (5.2%).

CONCLUSIONS

In real-world clinical practice, monoclonal antibodies against CGRP proved to be effective treatments in resistant migraine patients.

Efficacy of ubrogepant based on prior exposure and response to triptans: A post hoc analysis

Objective

To determine the potential efficacy of ubrogepant for acute treatment of migraine based on historical experience with triptans.

Background

Although triptans have improved migraine treatment, their efficacy and tolerability may limit their utility in some individuals. Ubrogepant is a small‐molecule, oral calcitonin gene–related peptide receptor antagonist approved by the Food and Drug Administration for acute treatment of migraine in adults.

Methods

This post hoc analysis of pooled data from the pivotal trials ACHIEVE I and II, identically designed, randomized, double‐blind, phase 3, single‐attack trials of ubrogepant in adults with a history of migraine with/without aura, examined the efficacy and tolerability of ubrogepant 50 mg versus placebo based on participants’ historical experience with triptans: triptan responder, triptan‐insufficient responder, and triptan naïve. Co‐primary efficacy endpoints were pain freedom and absence of most bothersome migraine‐associated symptom (MBS) 2 h post initial dose. Adverse events (AEs) within historical triptan experience subgroups were evaluated.

Results

In the pooled analysis population (n = 1799), 682 (placebo, n = 350; ubrogepant 50 mg, n = 332), 451 (placebo, n = 223; ubrogepant, n = 228), and 666 (placebo, n = 339; ubrogepant, n = 327) participants were triptan responders, triptan‐insufficient responders, and triptan‐naïve, respectively. Response rates on co‐primary efficacy endpoints were higher for ubrogepant versus placebo across all groups. Treatment‐by‐subgroup interaction p values based on odds ratios for pain freedom (p = 0.290) and absence of MBS (p = 0.705) indicated no significant impact of historical triptan experience on ubrogepant efficacy. AE incidence for ubrogepant did not differ appreciably across historical triptan experience subgroups.

Conclusions

Ubrogepant efficacy and tolerability did not differ for the acute treatment of migraine in participants classified as triptan responders, triptan‐insufficient responders, and triptan‐naïve based on their historical experience with triptans.

Cost-Effectiveness of Erenumab for the Preventive Treatment of Migraine in Patients with Prior Treatment Failures in Sweden

BACKGROUND

Migraine is a common neurological disease that disproportionately affects females and has a peak incidence during productive years, resulting in significant burden.

OBJECTIVE

The aim of the study was to determine the cost effectiveness of erenumab for the preventive treatment of migraine.

METHODS

A hybrid decision-tree plus Markov model was developed to evaluate the cost effectiveness of erenumab as a migraine treatment compared with best supportive care only for patients experiencing at least 4 monthly migraine days for whom at least two prior preventive treatments had failed. Clinical efficacy data were based on results from four randomized controlled trials of erenumab against placebo. The primary outcomes were costs, migraine days, and quality-adjusted life-years (QALYs). An incremental cost-effectiveness ratio (ICER) was estimated as the cost per QALY gained. The cost per migraine day avoided was also estimated, as were disaggregated direct and indirect costs. The analysis was conducted from Swedish societal and healthcare system perspectives based on total migraine, chronic migraine and episodic migraine populations, using a discount rate of 3% applied to both costs and health benefits and using year 2019 values.

RESULTS

In the base-case deterministic analyses, erenumab treatment resulted in ICERs of Swedish krona (SEK) 34,696 (€3310) and SEK301,565 (€28,769) per QALY gained in the total migraine and episodic migraine populations, respectively. Erenumab was dominant in the chronic migraine population. In the total migraine population, the use of erenumab resulted in a net benefit to society of SEK81,739 (€7773) per patient, assuming a willingness-to-pay threshold of SEK300,000 (€28,528) per QALY.

CONCLUSIONS

Our analysis suggests that erenumab is a cost-effective treatment for migraine with a willingness-to-pay threshold of SEK300,000 per QALY.

Monoclonal antibodies blocking CGRP transmission: An update on their added value in migraine prevention

The avenue of effective migraine therapies blocking calcitonin gene-related peptide (CGRP) transmission is the successful outcome of 35 years of translational research. Developed after short-acting, the small antagonists of the CGRP receptor (the "gepants"), the monoclonal antibodies blocking CGRP or its receptor (CGRP/rec mAbs) have changed the paradigm in migraine treatment. Contrary to the classical acute medications like triptans or nonsteroidal anti-inflammatory drugs (NSAIDs) with a transient effect, they act for long durations exclusively in the peripheral portion of the trigeminovascular system and can thus be assimilated to a durable attack treatment, unlike the classical preventives that chiefly act upstream on the central facets of migraine pathophysiology. Randomized controlled trials (RCT) of eptinezumab, erenumab, fremanezumab and galcanezumab have included collectively several thousands of patients, making them the most extensively studied class of preventive migraine treatments. Their results clearly indicate that CGRP/rec mAbs are significantly superior to placebo and have been comprehensively reviewed by Dodick [Cephalalgia 2019;39(3):445-458]. In this review we will briefly summarize the placebo-subtracted outcomes and number-needed-to-treat (NNT) of these pivotal RCTs and analyze new and post-hoc studies published afterwards focusing on effect size, effect onset and sustainability, response in subgroups of patients, safety and tolerability, and cost-effectiveness. We will also summarize our limited real-world experience with one of the CGRP/rec mAbs. Although methodological differences and lack of direct comparative trials preclude any reliable comparison, the overall impression is that there are only minor differences in efficacy and tolerability profiles between the four monoclonals: the average placebo-subtracted 50% responder rates for reduction in migraine headaches are 21.4% in episodic migraine (NNTs: 4-5), 17.4% in chronic migraine (NNTs: 4-8). Patients with an improvement exceeding 50% are rare, chronic migraineurs with continuous headache are unlikely to be responders and migraine auras are not improved. The effect starts within the first week after administration and is quasi maximal at one month. It is sustained for long time periods and may last for several months after treatment termination. CGRP/rec mAbs are effective even after prior preventive treatment failures and in patients with medication overuse, but the effect size might be smaller. They significantly reduce disability and health care resource utilization. The adverse effect profile of CGRP/rec mAbs is close to that of placebo with few minor exceptions and despite concerns related to the safeguarding role of CGRP in ischemia, no treatment-related vascular adverse events have been reported to date. Putting the CGRP/rec mAbs in perspective with available preventive migraine drug treatments, their major advantage seems not to be chiefly their superior efficacy but their unprecedented efficacy over adverse event ratio. Regarding cost-effectiveness, preliminary pharmaco-economic analyses of erenumab suggest that it is cost-effective for chronic migraine compared to no treatment or to onabotulinumtoxinA, but likely not for episodic migraine unless attack frequency is high, indirect costs are considered and its price is lowered.

Multidimensional assessment of the effects of erenumab in chronic migraine patients with previous unsuccessful preventive treatments: a comprehensive real-world experience

BACKGROUND

erenumab was safe and effective in clinical trials for the prevention of migraine. However, real-life data are still lacking. Here we report the clinical experience from an Italian real-world setting using erenumab in patients with chronic migraine experiencing previous unsuccessful preventive treatments.

METHODS

Seventy patients with chronic migraine and failure to ≥4 migraine preventive medication classes initially received monthly erenumab 70 mg s.c. Patients without a clinically meaningful improvement, considered as a > 30% reduction in headache days per month, after ≥3 months of therapy switched to monthly erenumab 140 mg. At the first administration and after 3 and 6 months, patients underwent extensive interviews to assess clinical parameters of disease severity and migraine-related disability and impact, and validated questionnaires to explore depression/anxiety, sleep, and quality of life (QoL). Finally, the Pain Catastrophizing Scale, Allodynia Symptom Checklist-12 and MIGraine attacks-Subjective COGnitive impairments scale (MIG-SCOG) were administered.

RESULTS

70% of patients were "responders" after the third administration of erenumab 70 mg, whereas 30% switched to erenumab 140 mg; 29% (6 pts) responded after the sixth administration. The headache-day frequency was reduced from 21.1 ± 0.7 to 11.4 ± 0.9 days after the third administration (p < 0.001) and to 8.9 ± 0.7 days after the sixth administration (p < 0.001). 53% and 70% of patients, respectively, showed a reduction of ≥50% of headache days/month after the third and the sixth administrations. Also improved were headache pain severity, migraine-related disability, and impact on daily living, QoL, pain catastrophizing and allodynia (all p < 0.001), quality of sleep, symptoms of depression or anxiety (p < 0.05) but not MIG-SCOG. There were no new adverse event signals.

CONCLUSION

These real-world data support monthly erenumab 70 or 140 mg s.c. as a safe and effective preventive treatment to reduce headache frequency and severity in chronic migraine patients experiencing previous unsuccessful preventive treatments.

Efficacy, tolerability, and safety of erenumab for the preventive treatment of persistent post-traumatic headache attributed to mild traumatic brain injury: an open-label study

BACKGROUND

Calcitonin gene-related peptide (CGRP) has recently been implicated in the pathogenesis of post-traumatic headache (PTH), which raises the prospect for therapeutic use of monoclonal antibodies targeting CGRP or its receptor. Therefore, we decided to assess the efficacy, tolerability, and safety of erenumab for prevention of persistent PTH attributed to mild traumatic brain injury.

METHODS

A single-center, non-randomized, single-arm, open-label study of erenumab for adults aged 18-65 years with persistent PTH. Patients were assigned to receive 140-mg erenumab monthly by two subcutaneous 1-mL injections, given every 4 weeks for 12 weeks. The primary outcome measure was the mean change in number of monthly headache days of moderate to severe intensity from baseline (4-week pretreatment period) to week 9 through 12. Tolerability and safety endpoints were adverse events (i.e. number and type).

RESULTS

Eighty-nine of 100 patients completed the open-label trial. At baseline, the mean monthly number of headache days of moderate to severe intensity was 15.7. By week 9 through 12, the number was reduced by 2.8 days. The most common adverse events were constipation (n = 30) and injection-site reactions (n = 15). Of 100 patients who received at least one dose of erenumab, two patients discontinued the treatment regimen due to adverse events.

CONCLUSIONS

Among patients with persistent PTH, erenumab resulted in a lower frequency of moderate to severe headache days in this 12-week open-label trial. In addition, erenumab was well-tolerated as discontinuations due to adverse events were low. Placebo-controlled randomized clinical trials are needed to adequately evaluate the efficacy and safety of erenumab in patients with persistent PTH.

TRIAL REGISTRATION

ClinicalTrials.Gov, NCT03974360. Registered on April 17, 2019 - Retrospectively registered.

The role of erenumab in the treatment of migraine

Calcitonin gene related peptide (CGRP) monoclonal antibodies (mAbs) have been the first class of specifically developed preventive treatments for migraine. Clinical trials data suggest superiority of the CGRP mAbs to placebo in terms of prevention of migraine symptoms, migraine-specific quality of life and headache related disability. Treatment-related side effects overall did not differ significantly from placebo and discontinuation rate due to side effects has been low across the clinical trials, perhaps in view of their peripheral mode of action. Along with their route and frequency of administration, these novel class of drugs may constitute an improvement compared with the established arsenal of migraine treatments. Erenumab is a fully human antibody and the only mAb acting on the CGRP pathway by blocking its receptor. It is the first of the CGRP mAb class approved by the US Food and Drug Administration (May 2018) and the European Medicines Agency (July 2018). Erenumab exists in two different doses (70 mg and 140 mg) and it is administered with monthly subcutaneous injections. This review summarises erenumab pharmacological characteristics, clinical trials data, focusing on the potential role of this treatment in clinical practice.

Novelty in Inflammation and Immunomodulation in Migraine

BACKGROUND

Migraine is a diffuse and disabling disease. Its pathophysiology is complex and involves both central and peripheral dysfunctions.

OBJECTIVE

This review will discuss the pathogenesis of migraine from the origin of the neuro-inflammatory theory, to the modern pathophysiological model and the latest therapies.

METHODS

PUBMED and EMBASE (up to May 2019) were searched for: migraine, inflammation, immunomodulation. An additional search was carried out from the bibliography of previous review articles.

RESULTS

Migraine was thought to be mainly a vascular disorder, according to the so-called "vascular theory". Based on animal models, a new hypothesis called "the neuro-inflammatory" was conceived at the end of the 20th century. The growing knowledge about the trigeminovascular system and its role in the inflammatory-pain pathway, allowed to identify other specific neurotransmitters, such as the Calcitonin Gene-Related Peptide and Pituitary Adenylate Cyclase-Activating Peptide. Evidence was provided that the inflammatory-pain system could become sensitised and, due to this sensitisation, the pain could also perpetuate, even in the absence of any triggers of the migraine attack. At last, brain immune cells modification during cortical spreading depression in migraine was demonstrated, along with the existence and function of the glymphatic system. The better comprehension of the immune system abnormalities allowed the development of new immunomodulating drugs: the monoclonal antibodies against the CGRP or the CGRP receptor. Moreover, new insights into the molecular mechanism of CGRP, and the function of C-fibres and Aδ-fibres, highlighted the mechanism of action of Botulinum Toxin type A in the treatment of chronic migraine.

Efficacy of galcanezumab in patients with episodic migraine and a history of preventive treatment failure: results from two global randomized clinical trials

BACKGROUND AND PURPOSE

The efficacy of galcanezumab, a monoclonal antibody for migraine prevention, has been demonstrated in two pivotal trials in patients with episodic migraine.

METHODS

EVOLVE-1 and EVOLVE-2 were identical phase 3, randomized, double-blind, placebo-controlled studies in patients with episodic migraine. Mean migraine headache days per month at baseline was 9. Patients were randomized 2:1:1 to monthly injections of placebo, galcanezumab 120 mg/240 mg during the 6-month double-blind treatment period. Key efficacy outcomes were assessed in subgroups amongst patients for whom, previously, for efficacy and/or safety/tolerability reasons (i) one or more (≥1) preventives failed, (ii) two or more (≥2) preventives failed and (iii) preventives were never used, or used but not failed (no prior failure).

RESULTS

In an integrated analysis of EVOLVE studies, galcanezumab 120 mg/240 mg versus placebo led to larger overall mean (SE) reductions in monthly migraine headache days across 6 months in patients with prior preventive failures (P < 0.001): ≥1 failure: 120 mg: -4.0 (0.4); 240 mg: -4.2 (0.5); placebo: -1.3 (0.4); ≥2 failures: 120 mg: -3.1 (0.7); 240 mg: -3.8 (0.8); placebo: -0.5 (0.6). Similar results were observed amongst patients with no prior failure, but the placebo response was larger: 120 mg: -4.7 (0.2); 240 mg: -4.5 (0.2); placebo: -3.0 (0.2) (P < 0.001 versus placebo). Significant improvements were observed with galcanezumab versus placebo for ≥50% and ≥75% reduction in monthly migraine headache days.

CONCLUSION

In patients with episodic migraine treated with galcanezumab, those with ≥1 or ≥2 prior preventive failures had significantly larger improvements, versus placebo, in efficacy outcomes. Similar results were observed in patients with no prior failure, with a larger placebo response.

Targeting calcitonin gene-related peptide: a new era in migraine therapy

Migraine is one of the most prevalent and disabling diseases worldwide, but until recently, few migraine-specific therapies had been developed. Extensive basic and clinical scientific investigation has provided strong evidence that the neuropeptide calcitonin gene-related peptide (CGRP) has a key role in migraine. This evidence led to the development of small molecule CGRP receptor antagonists and monoclonal antibodies targeting either CGRP or its receptor. Clinical trials investigating these therapies have consistently shown statistically significant efficacy for either the acute or preventive treatment of migraine. No serious safety or tolerability issues have been identified in the trials of the monoclonal antibody therapies. Although the appropriate place of these new migraine-specific therapies relative to other available acute and preventive treatments remains to be determined, a growing body of evidence shows that therapeutic approaches targeting CGRP have the potential to transform the clinical management of migraine.

Recent Advances in Pharmacotherapy for Episodic Migraine

In 2018, three calcitonin gene-related peptide (CGRP) pathway monoclonal antibodies, erenumab, fremanezumab and galcanezumab, were approved in various parts of the world, including Europe and the US, and another, eptinezumab, is pending, for the prevention of migraine. In this article, episodic migraine treatment is reviewed, although these medicines are approved and are just as effective for chronic migraine. These new medicines usher a new phase in the preventive management of migraine with migraine-specific treatments. Data from phase III trials of CGRP pathway monoclonal antibodies have shown they are efficacious, with adverse effect rates comparable to placebo. The combination of clear efficacy and excellent tolerability will be welcome in an area where poor adherence to current preventives is common. Rimegepant, ubrogepant and lasmiditan are migraine-specific acute therapies yet to be approved by regulators. Phase III data for the respective CGRP receptor antagonists, the gepants, and the serotonin 5-HT_1F receptor agonist, the ditan, have been positive and free of cardiovascular adverse effects. These medicines are not vasoconstrictors. When approved, they could meet the acute therapy demand of patients with cardiovascular risk factors where triptans are contraindicated. Beyond this, gepants will see the most disruptive development in migraine management in generations with medicines that can have both acute and preventive effects, the latter evidenced by data from the discontinued drug telcagepant and the early-phase drug atogepant. Moreover, one can expect no risk of medication overuse syndromes with gepants since the more patients take, the less migraines they have. During the next years, as experience with monoclonal antibodies grows in clinical practice, we can expect an evolution in migraine management to take shape. Clinicians will be able to offer treatment patients want rather than trying to fit migraineurs into therapeutic boxes for their management. Despite pessimistic susurrations of a largely addlepated form, many patients, and physicians, will welcome new options, and the challenges of new treatment paradigms, with optimism.

The appropriate dosing of erenumab for migraine prevention after multiple preventive treatment failures: a critical appraisal

Background

Erenumab, a fully human monoclonal antibody directed against the calcitonin gene-related peptide receptor, was approved for the prevention of episodic (EM) or chronic migraine (CM) at the monthly dose of 70 mg or 140 mg. We reviewed the available literature to understand if patients with prior preventive treatment failures benefit more from the 140 mg dose than the 70 mg.

Main body

We searched papers indexed in PubMed and conference abstracts published in the last 2 years which assessed the safety and efficacy of erenumab in patients with prior preventive treatment failures. We reviewed the results of 3 randomized controlled trials and their subgroup analyses and open-label extensions. The 140 mg monthly dose of erenumab had a numerical advantage over the 70 mg monthly dose in patients with prior preventive treatment failures, both in EM and CM (with or without medication overuse) during the double blind phases of the trials and their open-label extensions. The numerical difference between the two doses increased with the increase in the number of prior preventive treatment failures.

Conclusions

The available data suggest that erenumab 140 mg monthly might be preferred over the 70 mg monthly dose in patients with EM or CM and prior preventive treatment failures. Further data are needed to assess the long-term efficacy in clinical practice of the two doses of erenumab, while their safety profile is comparable.

Monoclonal antibodies for the prevention of migraine

Introduction: Calcitonin Gene-Related Peptide (CGRP) plays a crucial role in migraine pathophysiology. A novel specific treatment strategy for the prevention of migraine incorporates monoclonal antibodies (mAbs) against CGRP and its canonical receptor. Eptinezumab, fremanezumab and galcanezumab block CGRP mediated effects by binding to the peptide, while erenumab blocks the CGRP receptor.Areas covered: Following a brief overview of pharmacological characteristics, we will review phase III trials for the use of CGRP mAbs in the prevention of episodic and chronic migraine.Expert opinion: All four CGRP mAbs demonstrated an excellent safety, tolerability and efficacy profile in migraine patients. Across all trials mAbs showed superior efficacy for the reduction of monthly migraine days compared to placebo with a net benefit of 2.8 days. Neither cardiovascular nor immunological safety concerns have emerged from clinical trials. Fremanezumab, galcanezumab, and erenumab are approved in the USA and Europe. Based on trial data there is no reason why these mAbs should not become first-line therapies in future. For now, we advocate for the use of mAbs in migraine prevention for patients who failed a minimum of two standard oral treatments based on the novelty and costs of this approach. mAbs are also effective in patients with medication overuse and with comorbid depression or anxiety disorders. Taken together, mAbs are likely to usher in a new era in migraine prevention and provide significant value to patients.

Prophylactic Treatment of Pediatric Migraine: Is There Anything New in the Last Decade?

Migraine is a frequent and very disabling disease, especially at pediatric age. Despite this, there are few controlled data on the prophylactic treatment of primary headaches in this category of age. Given that the recently introduced calcitonin gene-related peptide (CGRP) inhibitors (CGRP-r) are still limited to adulthood, there is no drug with exclusive indication for migraine treatment in pediatric age. This raises several limitations in terms of adherence and effectiveness of the therapy. Moreover, the scenario is complicated by placebo response, which is larger in children and adolescents than in adults and often leads to an improvement in the attack frequency even in absence of any active pharmacological treatment. Our aim was to investigate the real evidence concerning the prophylactic therapy of pediatric migraine by reviewing the clinical studies published between 2010 and 2019.