TEV-48125 for the preventive treatment of chronic migraine: Efficacy at early time points

Efficacy and Safety of Anti-CGRP Monoclonal Antibodies in Prevention of Chronic Migraine: A Bayesian Network Meta-analysis

Due to the unmet needs in the management of migraine, a primary headache, and disabling disorder, the past decade has focused on developing monoclonal antibodies (mAbs) against the calcitonin-gene-related peptide (CGRP) as migraine prophylactic agents. The objective of the study was to evaluate the efficacy and safety of various anti-CGRP mAbs in the prevention of chronic migraine. Network meta-analysis (NMA) was performed using the Bayesian framework to estimate the efficacy and safety of mAbs after performing a literature search in PubMed, MEDLINE, Cochrane database, and International Clinical Trial Registry Platform (ICTRP). The outcomes calculated were in terms of mean difference (MD) or odds ratio (OR) with a 95% credible interval (95%CrI). Network graphs were constructed and node-split analysis was done to analyze the inconsistency. The NMA included a total of 10 clinical trials. Galacanezumab (120 mg) (MD: -2.7; 95%CrI: -4.8 to -0.83) was found to be better than other mAbs in terms of the difference in mean migraine days (MMD). Fremanezumab quarterly dose administration showed the best response (OR: 2.9; 95%CrI: 1.9 to 4.6) in terms of responder rate. Eptinezumab was found to be safer (OR: 0.88; 95%CrI: 0.61-1.3) as compared to other mAbs in terms of the rate of adverse events. Fremanezumab (quarterly) ranked better in terms of response rate, and eptinezumab was found to be the safest in the prophylactic management of migraine. Galacenequmab was better at reducing MMD. Further studies are needed to evaluate the long-term safety, efficacy, and use of mAbs in migraine patients.

Migraine: Advances in the Pathogenesis and Treatment

This article presents a comprehensive review on migraine, a prevalent neurological disorder characterized by chronic headaches, by focusing on their pathogenesis and treatment advances. By examining molecular markers and leveraging imaging techniques, the research identifies key mechanisms and triggers in migraine pathology, thereby improving our understanding of its pathophysiology. Special emphasis is given to the role of calcitonin gene-related peptide (CGRP) in migraine development. CGRP not only contributes to symptoms but also represents a promising therapeutic target, with inhibitors showing effectiveness in migraine management. The article further explores traditional medical treatments, scrutinizing the mechanisms, benefits, and limitations of commonly prescribed medications. This provides a segue into an analysis of emerging therapeutic strategies and their potential to enhance migraine management. Finally, the paper delves into neuromodulation as an innovative treatment modality. Clinical studies indicating its effectiveness in migraine management are reviewed, and the advantages and limitations of this technique are discussed. In summary, the article aims to enhance the understanding of migraine pathogenesis and present novel therapeutic possibilities that could revolutionize patient care.

Gender bias in clinical trials of biological agents for migraine: A systematic review

Migraine is considered one of the most disabling diseases. Currently, there are few studies on clinical migraine treatment based on sex-related differences, despite the important role of sex in migraine. Our aim was to evaluate gender bias in published clinical trials on monoclonal antibodies (erenumab, galcanezumab, fremanezumab and eptinezumab). We performed a systematic review of controlled clinical trials of erenumab, galcanezumab, fremanezumab and eptinezumab, searching the PubMed/MEDLINE database for articles published before December 2021. The search identified 760 articles, 25 of which met the inclusion criteria. Of all the patients included in these trials, 85.1% were women. Only one study had female lead authors. Two of the 25 studies included a sex-based analysis of the primary endpoint. None of the articles discussed the results separately for men and for women. The proportion of men recruited in trials is scarce and more studies are needed to guarantee the safety and tolerability of monoclonal antibodies used in male migraine. As observed in our study, despite the high number of women recruited, only 2 studies analysed the results separately by sex. Thus, a potential risk of gender bias was found in these clinical trials.

Fremanezumab for Chronic Migraine Prevention in Japanese Patients: Subgroup Analysis from Two International Trials

Purpose

Fremanezumab monoclonal antibody therapy has demonstrated efficacy for chronic migraine (CM) with rapid onset and good tolerability. This subgroup analysis of two clinical trials (Japanese and Korean CM Phase 2b/3 [NCT03303079] and HALO CM Phase 3 [NCT02621931]) aimed to evaluate the efficacy and safety of fremanezumab in Japanese patients.

Patients and Methods

Both trials randomly assigned eligible patients at baseline (1:1:1 ratio) to subcutaneous monthly fremanezumab, quarterly fremanezumab, or placebo at 4-week intervals. The primary endpoint was the mean change from baseline in the monthly (28-day) average number of headache days of at least moderate severity during the 12-week period after the first dose of study medication (analyzed by ANCOVA over 12 weeks and MMRM over initial 4 weeks). Secondary endpoints examined other aspects of efficacy, including medication use and disability.

Results

A total of 479 and 109 patients were Japanese in the Japanese and Korean CM Phase 2b/3 and HALO CM trials, respectively. Baseline and treatment characteristics were generally similar between treatment groups for both trials. Results of subgroup analyses for the primary endpoint according to ANCOVA demonstrated the superiority of fremanezumab over placebo in Japanese patients (quarterly fremanezumab, p=0.0005; monthly fremanezumab, p=0.0002 in both trials). Results using the MMRM analysis confirmed the rapid onset of action in this population. Results of the secondary endpoints further supported the efficacy of fremanezumab in Japanese patients. Fremanezumab was well tolerated with nasopharyngitis and injection-site reactions representing the most common adverse events in all treatment groups.

Conclusion

Despite the limitations of subgroup analyses, these consistent results confirm the efficacy and tolerability of fremanezumab in Japanese patients with CM.

Calcitonin gene-related peptide in migraine: from pathophysiology to treatment

INTRODUCTION

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.

DEVELOPMENT

The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.

CONCLUSIONS

The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.

The importance of an early onset of migraine prevention: an evidence-based, hypothesis-driven scoping literature review

Recently approved migraine preventive therapies facilitate rapid control of migraine activity, potentially improving patients’ lives and minimizing the societal burden of migraine. This review synthesizes available evidence on rates and timing of early onset of migraine prevention and identifies patient-level outcomes related to early onset prevention. This evidence-based scoping review identified all available clinical trial evidence regarding the early onset of prevention of migraine, under the hypothesis ‘Patients with migraine (episodic or chronic) report additional benefits when receiving an approved migraine preventive treatment that demonstrates an early onset of prevention’. Early onset of prevention was defined as migraine preventive benefits within 30 days post-administration. PubMed, EMBASE, and CINAHL were searched for publications between 1988 and 2020. Overall, 16 publications described 18 studies. All studies were conducted in approved treatments [four anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies and one chemodenervation agent] in patients with episodic/chronic migraine; no publications were identified for traditional oral agents for early migraine prevention. Compared to placebo, erenumab (three studies) reduced weekly migraine days within 1 week; fremanezumab (six studies) increased reports of no headache of at least moderate severity on Day 1 and significantly reduced migraine frequency within 1 week; galcanezumab (three studies) significantly reduced the mean number of patients with migraine beginning Day 1 and each day of the first week; eptinezumab (four studies) significantly reduced migraine attack likelihood on Day 1 by > 50% versus baseline; and onabotulinumtoxinA (two studies) reduced headache and migraine days within 1 week. Four publications described function, disability, and quality of life improvements as early as Week 4; none reported cost–benefit. Anti-CGRP monoclonal antibodies (erenumab, fremanezumab, galcanezumab, and eptinezumab) and a chemodenervation agent (onabotulinumtoxinA) provide clinically relevant benefits during the first treatment week. Literature describing clinically relevant benefits regarding early onset of prevention in patients with migraine is limited.

Calcitonin gene-related peptide in migraine: from pathophysiology to treatment

INTRODUCTION

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.

DEVELOPMENT

The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.

CONCLUSIONS

The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.

Early response to eptinezumab indicates high likelihood of continued response in patients with chronic migraine

Background

A clinical ability to describe the response trajectory of patients receiving preventive migraine treatment could expedite and improve therapeutic management decisions. This post hoc analysis of the PROMISE-2 study evaluated the consistency and predictive power of Month 1 treatment response on later response in patients with chronic migraine.

Methods

PROMISE-2 was a double-blind, placebo-controlled trial that randomized adults with chronic migraine to eptinezumab 100 mg, 300 mg, or placebo administered IV every 12 weeks for up to 24 weeks (2 infusions over 6 study months). Migraine responder rates (MRRs) were calculated from monthly migraine days over 4-week intervals compared with baseline. Patients were grouped by MRR during Month 1 (< 25%, 25–< 50%, 50–< 75%, and ≥ 75%), with the number of subsequent study months (Months 2–6) with ≥50% and ≥ 75% MRR calculated in each subgroup. A similar analysis was conducted using Patient Global Impression of Change (PGIC) rating to define Month 1 subgroups (very much improved, much improved, minimally improved, and no change/worse) and rates of very much improved or much improved PGIC during Months 2–6.

Results

In the eptinezumab 100 mg, 300 mg, and placebo groups, respectively, 194/356 (54.5%), 212/350 (60.6%), and 132/366 (36.1%) patients were ≥ 50% migraine responders during Month 1. More eptinezumab-treated patients were ≥ 75% migraine responders (100 mg, 110/356 [30.9%]; 300 mg, 129/350 [36.9%]; placebo, 57/366 [15.6%]) and more placebo-treated patients were < 25% migraine responders (eptinezumab 100 mg, 103/356 [28.9%]; 300 mg, 80/350 [22.9%]; placebo, 153/366 [41.8%]). Among patients who achieved ≥75% migraine response in Month 1, more than one-third attained ≥75% migraine response for all 5 subsequent study months and more than two-thirds achieved ≥75% migraine response for ≥3 months. More than two-thirds of those in the very much improved (PGIC) subgroup at Month 1 were much or very much improved for all 5 subsequent months.

Conclusions

In this post hoc analysis of data from PROMISE-2, more eptinezumab-treated than placebo-treated patients were early (Month 1) responders, and most early responders went on to achieve a high level of response for at least half of the 24-week treatment period. Potential for later response in early non-responders was also observed.

Trial registration

ClinicalTrials.gov identifier: NCT02974153; registered November 23, 2016.

The importance of an early onset of migraine preventive disease control: A roundtable discussion

Background:

Newly approved migraine preventive therapies have allowed for rapid control of migraine activity, offering potential to minimize the burden of migraine. This report summarizes a roundtable discussion convened to analyze evidence for early onset of prevention, ascertain its clinical relevance, and provide guidance for healthcare professionals in crafting goals and treatment expectations for patients with migraine initiating preventive therapy.

Methods:

A virtual roundtable meeting of migraine clinicians, researchers, and patient advocates convened in October 2020. Participants reviewed and discussed data summarizing patient and healthcare professional perceptions of migraine prevention and evidence from the peer-reviewed and gray literature to develop corresponding recommendations.

Summary:

Evidence from clinical studies of anti-calcitonin gene-related peptide monoclonal antibodies (erenumab, fremanezumab, galcanezumab, and eptinezumab) and the chemodenervation agent onabotulinumtoxinA indicate that patients may experience reduction of migraine activity within 7 days of drug administration and early attainment of disease control is associated with improvements in clinically important outcomes. The roundtable of experts proposes that early onset be defined as demonstration of preventive benefits within 1 week of treatment initiation. We recommend focusing discussion with patients around “disease control” and potential benefits of early onset of prevention, so patients can set realistic preventive therapy goals and expectations.

Comparative Effectiveness and Tolerability of the Pharmacology of Monoclonal Antibodies Targeting the Calcitonin Gene-Related Peptide and Its Receptor for the Prevention of Chronic Migraine: a Network Meta-analysis of Randomized Controlled Trials

Monoclonal antibodies (mAbs) acting on the calcitonin gene-related peptide (CGRP) or on its receptor are new therapeutic biologics to prevent chronic migraine (CM). Four mAbs acting on the CGRP or on its receptor are new therapeutic biologics to prevent CM. The aim of current network meta-analysis (NMA) was to compare the efficacy and acceptability of CGRP mAbs with onabotulinumtoxinA or topiramate for CM. We included randomized controlled trials (RCTs) examining CGRP mAbs and onabotulinumtoxinA or topiramate in patients with CM. All network meta-analytic procedures were conducted using the frequentist model. The primary outcomes were changes in the monthly migraine days and the 50% response rate. The safety was evaluated with acceptability (i.e., drop-out rate) and rate of any adverse event. This NMA of thirteen RCTs, which, in total, consisted of 5634 participants, demonstrated that a single 300 mg of eptinezumab (mean difference =  - 2.60 days, 95% confidence intervals (95% CIs) =  - 4.43 to - 0.77 compared with placebo) demonstrated the best improvement in monthly migraine days among all interventions. In addition, 675 mg fremanezumab in the first month followed by 225 mg in the second and third months (odds ratio (OR) = 2.96, 95% CIs = 2.20 to 3.97 compared to placebo) was associated with the best response rate among all the interventions. Monthly 140 mg erenumab (MD =  - 2.50 days, 95% CIs =  - 3.83 to - 1.17 compared with placebo) was the best choice for reducing the number of acute migraine-specific medication use days. The safety analysis revealed that loading dose of 240 mg galcanezumab and monthly 240 mg (OR = 0.43, 95% CIs = 0.22 to 0.84) was associated with the lowest drop-out rate; loading dose fremanezumab 675 mg and monthly 675 mg (OR = 1.44, 95% CIs = 1.10 to 1.89), loading dose of 240 mg galcanezumab and monthly 120 mg (OR = 1.37, 95% CIs = 1.02 to 1.84), and single dose of fremanezumab 675 mg (OR = 1.35, 95% CIs = 1.00 to 1.83) were associated with significantly higher rates of AEs than the placebo/control groups. Our NMA indicated that all four CGRP mAbs demonstrated excellent safety, acceptability, and efficacy profiles compared to the traditional prophylaxis for CM. However, because there are several limitations, the findings of the current NMA should be taken into consideration with caution.

Efficacy and safety of fremanezumab for episodic migraine prevention: Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial in Japanese and Korean patients

OBJECTIVE

To evaluate the efficacy and safety of two dosing regimens of fremanezumab in Japanese and Korean patients with episodic migraine.

BACKGROUND

Episodic migraine, which accounts for more than 90% of migraine cases, is inadequately addressed by widely available preventive therapies. Fremanezumab, a monoclonal antibody that selectively targets the trigeminal sensory neuropeptide calcitonin gene-related peptide involved in migraine pathogenesis, has demonstrated efficacy in international Phase 3 trials of patients with both chronic and episodic migraine.

METHODS

This Phase 3 randomized, placebo-controlled trial randomly assigned patients with episodic migraine to receive subcutaneous fremanezumab monthly (225 mg at baseline, week 4, and week 8), fremanezumab quarterly (675 mg at baseline and placebo at weeks 4 and 8), or matching placebo. The primary endpoint was the mean change from baseline in the monthly average number of migraine days during the 12-week treatment period after the first dose.

RESULTS

Of 357 patients enrolled (safety set, n = 356; full analysis set, n = 354), the least-squares mean (±standard error) reductions in the average number of migraine days per month during 12 weeks were significantly greater with fremanezumab monthly (-4.0 ± 0.4, n = 121) and fremanezumab quarterly (-4.0 ± 0.4, n = 117) than with placebo (-1.0 ± 0.4, n = 116; p < 0.0001 for both comparisons). The proportion of patients reaching at least a 50% reduction in the monthly average number of migraine days during the 12-week period after initial administration was also significantly improved with fremanezumab (fremanezumab monthly, 41.3%; fremanezumab quarterly, 45.3%; placebo, 11.2%; p < 0.0001 for both comparisons) as were other secondary endpoints (p < 0.001 for all comparisons between fremanezumab and placebo). Injection-site reactions were more common in fremanezumab-treated patients (fremanezumab monthly, 25.6%; fremanezumab quarterly, 29.7%; placebo, 21.4%).

CONCLUSION

Fremanezumab prevents episodic migraine in Japanese and Korean patients to a similar extent than in previously reported populations with no new safety concerns.

CGRP and migraine; from bench to bedside

Migraine treatment has reached a new era with the development of drugs that target the trigeminal neuropeptide calcitonin gene-related peptide (CGRP) or its receptor. The CGRP related therapies offer considerable improvements over existing drugs as they are the first to be designed to act on the trigeminal pain system, more specific and with few adverse events. Small molecule CGRP receptor antagonists, such as rimegepant and ubrogepant, are effective for the acute treatment of migraine headache. In contrast, monoclonal antibodies against CGRP or the CGRP receptor are beneficial for the prophylactic treatments in chronic migraine. Here I will provide a historical overview of the long path that led to their successful development. In addition, I will discuss aspects on the biology of CGRP signalling, the role of CGRP in migraine headache, the efficacy of CGRP targeted treatment, and synthesize what currently is known about the role of CGRP in the trigeminovascular system.

Efficacy and safety of fremanezumab for chronic migraine prevention: Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial in Japanese and Korean patients

OBJECTIVE

To determine the efficacy and safety of fremanezumab administration in Japanese and Korean patients with chronic migraine (CM).

BACKGROUND

Available preventive treatments for CM are limited by various efficacy and safety issues. Fremanezumab, a monoclonal antibody that targets the calcitonin gene-related peptide pathway involved in migraine pathogenesis, has been shown to be effective and well tolerated in large-scale, international Phase 3 trials.

METHODS

Randomized, placebo-controlled trial of patients with CM who received subcutaneous fremanezumab monthly (675 mg at baseline and 225 mg at weeks 4 and 8), fremanezumab quarterly (675 mg at baseline and placebo at weeks 4 and 8), or matching placebo. Primary endpoint was the mean change from baseline in the monthly (28-day) average number of headache days of at least moderate severity during the 12 weeks after the first dose.

RESULTS

Among 571 patients randomized (safety set, n = 569; full analysis set, n = 566), the least-squares mean (±standard error [SE]) reduction in the average number of headache days of at least moderate severity per month during 12 weeks was significantly greater with fremanezumab monthly (-4.1 ± 0.4) and fremanezumab quarterly (-4.1 ± 0.4) than with placebo (-2.4 ± 0.4). The difference from the placebo group in the mean change (95% confidence interval [CI]) was -1.7 days (-2.54, -0.80) for the fremanezumab monthly group and -1.7 days (-2.55, -0.82) for the fremanezumab quarterly group (p < 0.001 vs. placebo for both fremanezumab groups). The percentage of patients with a ≥50% reduction in the average number of headache days of at least moderate severity per month (response rate) was higher with fremanezumab monthly (29.0%) and fremanezumab quarterly (29.1%) than with placebo (13.2%) in addition to other improvements in secondary endpoints, including reduction of acute medication use (mean change from baseline during 12-week period ± SE: fremanezumab monthly, -3.7 ± 0.4; fremanezumab quarterly, -3.9 ± 0.4; placebo, -2.4 ± 0.4) and improvements in disability scores (mean change from baseline in six-item Headache Impact Test score at 4 weeks after third injection ± SE: fremanezumab monthly, -8.1 ± 0.7; fremanezumab quarterly, -8.0 ± 0.7; placebo, -6.5 ± 0.7). Fremanezumab was well tolerated with a similar incidence of adverse events including injection-site reactions as placebo (patients with at least one treatment-emergent adverse event: fremanezumab total, n = 232 [61.4%]; placebo, n = 118 [61.8%]).

CONCLUSION

Fremanezumab effectively prevents CM in Japanese and Korean patients and was well tolerated. No safety signal was detected.

Improvements in pain, medication use and quality of life in onabotulinumtoxinA-resistant chronic migraine patients following erenumab treatment - real world outcomes

Background

The CGRP antagonists offer a novel therapeutic approach in migraine. Their utility in patients with severe forms of chronic migraine is a subject of particular interest. We present outcomes of 9 months of erenumab treatment in a cohort of patients with difficult-to-control chronic migraine, all of whom had prior unsatisfactory response to onabotulinumtoxinA.

Methods

We offered erenumab to 98 patients with a prior unsatisfactory response to onabotulinumtoxinA. Eighty of 98 had trialled greater occipital nerve injections (82%), 32/98 peripheral neurostimulation (33%) and 18/98 intravenous dihydroergotamine (18%). Thirty eight of 98 (39%) met the definition of triptan overuse and 43/98 (44%) analgesic overuse. All patients met the EHF criteria for ‘resistant migraine’. Outcome measures (recorded monthly) included days with headache limiting activities of daily living (“red”), not limiting (“amber”), headache free (“green”), and requiring triptans or other analgesics. Quality of life scores - headache impact test 6 (HIT-6), patient health questionnaire 9 (PHQ-9) and pain disability index (PDI) - were also measured.

Results

Mean number of red days improved by − 6.4 days (SE 0.67, 95%CI − 7.7 to − 5.1, p=0.001) at 3 months; − 6.8 days (SE 0.96, 95%CI − 8.80 to − 4.9, p=0.001) at 6 months and − 6.5 days (SE 0.86, 95%CI − 8.3 to − 4.8, p=0.001) at 9 months. Repeated measures ANOVA confirmed improvements in the number of red (p=0.001), green (p=0.001), triptan (p=0.001) and painkiller days (p=0.001) as well as scores of the HIT-6 (p=0.001), PHQ-9 (p=0.001), and PDI (p=0.001) across the duration of study.

Conclusion

We observed improvements in pain, medication use and quality of life in onabotulinumtoxinA-resistant chronic migraine patients following erenumab treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-020-01214-2.

Eptinezumab Demonstrated Efficacy in Sustained Prevention of Episodic and Chronic Migraine Beginning on Day 1 After Dosing

Objective

To determine the onset of preventive efficacy with eptinezumab in patients with migraine.

Background

Eptinezumab is a monoclonal antibody inhibiting calcitonin gene‐related peptide approved as an intravenously administered treatment for the prevention of migraine.

Methods

Patients who received eptinezumab 100 mg, eptinezumab 300 mg, or placebo in PROMISE7‐1 (episodic migraine; 100 mg, n = 221; 300 mg, n = 222; placebo, n = 222) or PROMISE7‐2 (chronic migraine; 100 mg, n = 356; 300 mg, n = 350; placebo, n = 366) were included. Testing of the percentage of patients with a migraine on day 1 after dosing was prespecified and alpha‐controlled. In further exploration of this prespecified endpoint, a post hoc closed testing procedure, which controlled the false‐positive (type 1) error rate, provided a statistically rigorous evaluation of migraine prevention onset. The procedure involved up to 84 tests of significance, all of which were performed in sequence until the first nonsignificant result.

Results

For both studies, all tests for significance for eptinezumab 100 and 300 mg, from days 1‐84 through day 1 alone, achieved nominal significance (P < .05), indicating that eptinezumab was fully effective beginning on day 1. Over each interval, the treatment effect was comparable to the effect over weeks 1‐12. Mean changes from baseline in monthly migraine days for the primary endpoint period ranged from −3.9 to −4.9, −4.1 to −4.9, and −2.2 to −3.2 for eptinezumab 100, 300 mg, and placebo, respectively, in PROMISE7‐1 and from −7.2 to −8.0, −7.9 to −8.2, and −4.3 to −5.6, respectively, in PROMISE7‐2. The difference from placebo (95% confidence interval) in day 1 treatment effect was −2.2 (−4.1, −0.3) and −2.5 (−4.4, −0.6) days/month for eptinezumab 100 and 300 mg, respectively, in PROMISE7‐1, and was −3.8 (−5.6, −2.0) and −4.0 (−5.8, −2.1) days/month for 100 and 300 mg, respectively, in PROMISE7‐2.

Conclusions

The migraine preventive effect of eptinezumab is rapid and sustained in patients with episodic or chronic migraine, with onset of optimal preventive efficacy observed on the day following the initial dose.

Optimal treatment strategy of fremanezumab in migraine prevention: a systematic review with network meta-analysis of randomized clinical trials

Identifying the optimal fremanezumab treatment strategy is crucial in treating patients with migraines. The optimal strategy was investigated by assessing the cumulative 50% reduction rate (50%CRR), cumulative 75% reduction rate (75%CRR), reduction in the number of migraine days, treatment-related adverse events, and serious adverse events in patients treated with fremanezumab 225 mg monthly (225 mg), 675 mg monthly (675 mg), 900 mg monthly (900 mg), a single high dose of 675 mg (S675mg), 675 mg at baseline with 225 mg monthly (675/225 mg), and placebo. Biomedical databases were searched for randomized controlled trials on this topic, and data were individually extracted. Risk ratios and mean differences were used to present the pooled results. The surface under the cumulative ranking curve (SUCRA) was used to determine the effects of the medication strategies of fremanezumab. Five trials (n = 3404) were used to form a six-node network meta-analysis. All fremanezumab medication strategies displayed significantly higher cumulative 50% reduction rates than the placebo. The SUCRA revealed that treatment with 675 mg yielded the highest 50%CRR value (mean rank = 2.5). S675 mg was the only treatment with significantly higher 75%CRR reduction rate than placebo, whereas the SUCRA for 225 mg displayed the highest mean rank (2.2). Moreover, 225 mg (mean rank = 2.2) and S675 mg (mean rank = 2.2) presented lower probabilities of serious adverse events. Collectively, S675mg and 225 mg exhibited the optimal balance between efficacy and safety within three months. Long-term efficacy and safety remain unclear, and future studies should further evaluate the long-term outcomes.

Effect of Fremanezumab Monthly and Quarterly Doses on Efficacy Responses

OBJECTIVE

Exposure-response (E-R) models were developed to provide a description of the time-course of treatment effect for monthly and quarterly dosing regimens of fremanezumab.

BACKGROUND

Fremanezumab is a monoclonal antibody for preventive treatment of episodic migraine (EM) and chronic migraine (CM). In phase 2b and 3 clinical studies of fremanezumab, significant reductions in migraine and headache days and other clinical endpoints were observed for patients with EM and patients with CM. Development of E-R models relating individual-specific measures of drug exposure to clinical endpoints provides a more granular understanding of the expected effects of different doses on therapeutic outcomes by accounting for variability in pharmacokinetic (PK) properties.

METHODS

Data from 2 phase 2b and 2 phase 3 studies of adults with EM or CM were used. Individual exposures were calculated from a population PK model and related to monthly migraine days in EM and moderate-severe (M/S) headache days in CM. Model-based stochastic simulations were performed to compare predicted responses for the various treatment regimens.

RESULTS

The effect of average fremanezumab concentration compared to placebo on the reduction in migraine days and M/S headache days was predicted by the models to be similar for 225 mg monthly and 675 mg once quarterly over time for both EM and CM patients. Both regimens were associated with better response than placebo. A similar percent of EM and CM responders was predicted across the range of observed body weights.

CONCLUSIONS

Exposure-response evaluations showed that both monthly (225 mg) and quarterly (675 mg) fremanezumab dosing regimens were appropriate in achieving clinical benefit in adult patients with EM or CM.

Cost of fremanezumab, erenumab, galcanezumab and onabotulinumtoxinA associated adverse events, for migraine prophylaxis in Spain

Objective: To compare the cost of adverse events (AEs) associated with preventive treatment of migraine with fremanezumab, versus erenumab, galcanezumab, and onabotulinumtoxinA.Methods: A probabilistic modeling analysis was performed, using second-order Monte Carlo simulations, with 1,000 simulations, in patients with at least 4 days of migraine per month, from the perspective of the National Health System and a time horizon of 12 weeks. The frequency of AEs described in the clinical trials was analyzed with 12 weeks of treatment. Unit costs (€) of management of AEs were obtained from public health prices, expert panels, and published Spanish studies.Results: Fremanezumab would generate average savings of -€469 (95% CI -€303; -€674) versus erenumab, -€268 (95% CI -€171; -€391) versus galcanezumab, -€1,100 (95% CI -€704; -€1,608) or -€1,295 (95% CI -€835; -€1,893) versus onabotulinumtoxinA using real-life or clinical trial data, respectively.Conclusions: The different safety profile of treatment with fremanezumab, compared to erenumab, galcanezumab, and onabotulinumtoxinA, would generate savings in health-care resources in all the scenarios considered.

An Evidence-Based Review of Fremanezumab for the Treatment of Migraine

Migraine headache is a common, chronic, debilitating disease with a complex etiology. Current therapy for migraine headache comprises either treatments targeting acute migraine pain or prophylactic therapy aimed at increasing the length of time between migraine episodes. Recent evidence suggests that calcium gene-related peptide (CGRP) is a critical component in the pathogenesis of migraines. Fremanezumab, a monoclonal antibody against CGRP, was recently approved by the Food and Drug Administration (FDA) after multiple studies showed that it was well-tolerated, safe, and effective in the treatment of migraines. Further research is needed to elucidate the long-term effects of fremanezumab and CGRP-antagonists in general, and additional data is required in less healthy patients to estimate its effects in these populations and potentially increase the eligible group of recipients. This is a comprehensive review of the current literature on the efficacy and safety of fremanezumab for the treatment of chronic migraine. In this review we provide an update on the epidemiology, pathogenesis, diagnosis, and current treatment of migraine, and summarize the evidence for fremanezumab as a treatment for migraine.

Calcitonin gene-related peptide (CGRP): role in migraine pathophysiology and therapeutic targeting

Introduction: The neuropeptide calcitonin gene-related peptide (CGRP) is recognized as a critical player in migraine pathophysiology. Excitement has grown regarding CGRP because of the development and clinical testing of drugs targeting CGRP or its receptor. While these drugs alleviate migraine symptoms in half of the patients, the remaining unresponsive half of this population creates an impetus to address unanswered questions that exist in this field.Areas covered: We describe the role of CGRP in migraine pathophysiology and CGRP-targeted therapeutics currently under development and in use. We also discuss how a second CGRP receptor may provide a new therapeutic target.Expert opinion: CGRP-targeting drugs have shown a remarkable safety profile. We speculate that this may reflect the redundancy of peptides within the CGRP family and a second CGRP receptor that may compensate for reduced CGRP activity. Furthermore, we propose that an inherent safety feature of peptide-blocking antibodies is attributed to the fundamental nature of peptide release, which occurs as a large bolus in short bursts of volume transmission. These facts support the development of more refined CGRP therapeutic drugs, as well as drugs that target other neuropeptides. We believe that the future of migraine research is bright with exciting advances on the horizon.

Fremanezumab in the treatment of migraines: evidence to date

Calcitonin gene-related peptide (CGRP) is a major player in migraine pathophysiology, and CGRP monoclonal antibodies including fremanezumab may be a safe effective preventive therapy. Phase IIb studies in episodic migraine (EM) and chronic migraine (CM) demonstrated efficacy at both the monthly 225 mg and quarterly 675 mg doses. The Phase III trials for EM and CM both showed a reduction in the primary endpoint of monthly migraine days (MMD). In the EM trial, the baseline MMD of 8.9 days was reduced to 5.3 at 12 weeks and to 4.0 days in the 6-month open-label extension (OLE) for monthly dosing. In the quarterly dosing, the baseline was 9.2 days reduced to 5.3 at 12 weeks and to 4.2 days in the OLE. In the CM data for monthly dosing, the baseline was 16.2 days decreased to 11.4 at 12 weeks then to 8.3 in the OLE. In the CM quarterly dosing, the baseline of 16.4 days was reduced to 11.9 at 12 weeks and 9.9 days in the OLE. Randomized controlled trials of fremanezumab in both episodic cluster and post-traumatic headache are underway, but the trial for chronic cluster headache was stopped for futility. The most common adverse events are injection site pain (24% vs 22% for placebo), induration (17% vs 13% for placebo), and erythema (16% vs 12% for placebo). Severe adverse events were reported in 3.9% of the fremanezumab vs 3.7% of the placebo. No changes in vitals or ECG were reported. The long-term effects are not known, but the American Headache Society recommends that CGRP monoclonal antibodies be considered in EM or CM depending on previous medication trials and headache disability/frequency. Further, post-market studies are required, but for EM and CM fremanezumab is a new option for migraine preventive treatment.

Onset of efficacy and duration of response of galcanezumab for the prevention of episodic migraine: a post-hoc analysis

BACKGROUND AND OBJECTIVE

As new migraine prevention treatments are developed, the onset of a preventive effect, how long it is maintained and whether patients initially non-responsive develop clinically meaningful responses with continued treatment can be assessed.

METHODS

Analyses were conducted post-hoc of a double-blind, placebo-controlled, phase II-a study in patients with episodic migraine receiving galcanezumab 150 mg or placebo biweekly for 12 weeks (Lancet Neurol 13:885, 2014). The number of migraine headache days per week, and onset of efficacy measured as the first week galacanezumab separated from placebo were determined. Patients with ≥50%, ≥75% and 100% reduction in migraine headache days from baseline at months 1, 2 and 3 were calculated and defined as sustained responses. Non-responders (<50% response) at month 1 or 2 who then showed ≥50%, ≥75% and 100% response at later time-points were calculated.

RESULTS

Patients were randomised to galcanezumab (n=107) or placebo (n=110). A significant (p=0.018) change of -0.89±0.11 (galcanezumab) vs -0.53±0.11 (placebo) migraine headache days indicated onset at week 1. Forty-seven per cent of galcanezumab and 25% of placebo patients responding at month 1 maintained response through months 2 and 3. Of non-responders at month 1, 27% on galcanezumab and 20% on placebo responded on months 2 and 3, and 50% of galcanezumab non-responders in months 1 and 2 responded on month 3, vs 24% on placebo.

CONCLUSIONS

The onset of efficacy of galcanezumab is within 1 week in a majority of patients, and patients receiving galcanezumab are twice more likely to maintain responses than placebo patients. Early non-responders may respond by month 2 or month 3.

TRIAL REGISTRATION NUMBER

NCT01625988.

Effects of Anti-Calcitonin Gene-Related Peptide for Migraines: A Systematic Review with Meta-Analysis of Randomized Clinical Trials

We aimed to evaluate the response rate of migraines by using anti-calcitonin gene-related peptide (anti-CGRP) for patients with migraines. We searched three main medical databases up to 29 March 2019. No restriction on language and publication time were applied. Eligible trials included randomized clinical trials investigating a 50%, 75%, and 100% response rate of migraine patients after anti-CGRP intervention. The collected data were dichotomous, and risk ratios (RRs) with a 95% confidence interval (CI) were used to present the quantitative synthesis results. The systematic review identified 16 eligible randomized clinical trials (RCTs) with 9439 patients. Eight of the 16 trials with 2516 patients reported a 50% response rate, and the pooled results showed a significant benefit from anti-CGRP. However, the effects seem to gradually reduce from the first month (RR 1.99, 95% CI 1.59 to 2.49) to the third month (RR 1.48, 95% CI 1.26 to 1.75) of treatment. The magnitude of effect was influenced by the type of anti-CGRP, according to the test for differences between subgroups (I-square = 53%). The funnel plots and Egger's tests did not show serious small study effects in the results. In conclusion, the current evidences confirmed that anti-CGRP treatment can reduce migraine pain in the short term (within three months), but the long-term effect should be investigated in the future. Moreover, its effects may be influenced by the type and dose of anti-CGRP. Therefore, future studies should make direct comparisons among anti-CGRP medications.

Fremanezumab for the preventive treatment of migraine in adults

Introduction: The Calcitonin Gene-Related Peptide (CGRP) has been implicated in migraine pathophysiology due to its role in neurogenic inflammation and transmission of trigeminovascular nociceptive signal. New molecules targeting CGRP and its receptor have been developed as migraine-specific preventative treatments. Fremanezumab (or TEV-48,125, LBR-101), a human monoclonal antibody against CGRP, has been recently approved for clinical use by FDA and EMA. Areas covered: This paper briefly discusses the calcitonin family of neurotransmitters and resultant activation pathways and in-depth the chemical properties, pharmacodynamics, pharmacokinetics, clinical efficacy and safety of Fremanezumab for the prophylactic treatment of migraine. Expert opinion: Fremanezumab, a migraine-specific drug, is effective and safe as a prophylactic treatment of chronic and episodic migraine. As a monoclonal antibody, it was not associated to liver toxicity and is not expected to interact with other drugs. The long half-life might improve patients' compliance. Long-term effects of CGRP block in cardiovascular, grastrointestinal and bone functions should be evaluated in ongoing trials, since CGRP is involved in multiple biological activities in the human body. Nevertheless, targeting CGRP itself allows the receptor binding with other ligands involved in several physiological functions. Thus, the long-term treatment with Fremanezumab is expected to be associated with a lower risk of severe adverse effects.

Are antimigraine drugs that influence CGRP levels justified?

Migraine is one of the most common disorders found in everyday clinical practice. Although migraines are not directly life-threatening or permanently disabling, the severity of the pain and symptoms that characterize a migraine attack often prevent normal work and cause difficulties in everyday life. Migraines also affect the patient's family, who often experience stress and depression in response to the patient's condition. Available therapy, used in both acute and chronic treatments, might not provide sufficient improvement. Due to problems like therapy inefficacy, side effects, and intolerance, patients often stop treatments. Recent studies have indicated that drugs that act through calcitonin gene-related peptide (CGRP) can significantly improve migraine therapy. Here, we review results from currently available clinical trials on CGRP receptor antagonists and anti-CGRP monoclonal antibodies.

Adherence to the 2008 IHS guidelines for controlled trials of drugs for the preventive treatment of chronic migraine in adults

Introduction

Since the definition of chronic migraine as a new disease entity in 2004, numerous clinical trials have examined the efficacy of preventive treatments in chronic migraine. Our aim was to assess the adherence of these trials to the Guidelines of the International Headache Society published in 2008.

Methods

We searched PubMed for controlled clinical trials investigating preventive treatment for chronic migraine in adults designed after the release of the Guidelines and published until December 2017. Trial quality was evaluated with a 13-item scoring system enlisting essential recommendations adapted from the Guidelines.

Results

Out of 3352 retrieved records, we included 16 papers in the analysis dealing with pharmacological treatment of chronic migraine. The median score was 6.5 (range 2–13). All trials were randomized, the large majority (81.25%) were placebo-controlled and double-blinded (87.5%). Adherence was lowest on i) a priori definition of outcomes (31.25%), ii) primary endpoint definition (37.5%%) and iii) trial registration (37.5%).

Discussion

Most clinical trials adhered to the recommendations of the IHS, whereas adherence to migraine-specific recommendations was lower. Greater awareness and adherence to the guidelines are essential to improve the quality of clinical trials, validity of publications and the generalizability of the results.

Therapeutic novelties in migraine: new drugs, new hope?

Background

In the past decade, migraine research has identified novel drug targets. In this review, we discuss recent data on emerging anti-migraine therapies.

Main body

The development of ditans, gepants and anti-calcitonin gene-related peptide monoclonal antibodies for the treatment of migraine is one of the greatest advances in the migraine field. Lasmiditan, rimegepant and ubrogepant will extend our therapeutic armamentarium for managing acute migraine attacks when triptans are not effective or contraindicated due to cardiovascular disorders. The monoclonal antibodies are migraine specific prophylactic drugs with high responder rates and favorable adverse event profiles. Furthermore, they offer convenient treatment regimens of 4- or 12-week intervals.

Conclusion

Collectively, novel migraine therapies represent a major progress in migraine treatment and will undoubtedly transform headache medicine.

Once-monthly galcanezumab for the prevention of migraine in adults: an evidence-based descriptive review and potential place in therapy

In the last 15 years relevant efforts have been made to demonstrate that calcitonin gene-related peptide (CGRP) antagonism is a valuable and druggable mechanism for treatment or prevention of migraine. Galcanezumab is one of the antibodies developed and studied to prevent migraine by targeting CGRP. The scope of this review is to report data currently available on galcanezumab. According to available data, galcanezumab is safe and efficacious in preventing migraine in episodic migraine patients, also reducing disability and functional impairment due to the disorder. In September 2018, galcanezumab was approved in the USA for the prevention of migraine in adults. The placement of galcanezumab into the current therapeutic scenario will be a revolution for migraine patients, and probably in a less near future also for patients affected by other primary headaches.

TRP Channels and Migraine: Recent Developments and New Therapeutic Opportunities

Migraine is the second-most disabling disease worldwide, and the second most common neurological disorder. Attacks can last many hours or days, and consist of multiple symptoms including headache, nausea, vomiting, hypersensitivity to stimuli such as light and sound, and in some cases, an aura is present. Mechanisms contributing to migraine are still poorly understood. However, transient receptor potential (TRP) channels have been repeatedly linked to the disorder, including TRPV1, TRPV4, TRPM8, and TRPA1, based on their activation by pathological stimuli related to attacks, or their modulation by drugs/natural products known to be efficacious for migraine. This review will provide a brief overview of migraine, including current therapeutics and the link to calcitonin gene-related peptide (CGRP), a neuropeptide strongly implicated in migraine pathophysiology. Discussion will then focus on recent developments in preclinical and clinical studies that implicate TRP channels in migraine pathophysiology or in the efficacy of therapeutics. Given the use of onabotulinum toxin A (BoNTA) to treat chronic migraine, and its poorly understood mechanism, this review will also cover possible contributions of TRP channels to BoNTA efficacy. Discussion will conclude with remaining questions that require future work to more fully evaluate TRP channels as novel therapeutic targets for migraine.

Recent Advances in Pharmacotherapy for Migraine Prevention: From Pathophysiology to New Drugs

Migraine is a common and disabling neurological disorder, with a significant socioeconomic burden. Its pathophysiology involves abnormalities in complex neuronal networks, interacting at different levels of the central and peripheral nervous system, resulting in the constellation of symptoms characteristic of a migraine attack. Management of migraine is individualised and often necessitates the commencement of preventive medication. Recent advancements in the understanding of the neurobiology of migraine have begun to account for some parts of the symptomatology, which has led to the development of novel target-based therapies that may revolutionise how migraine is treated in the future. This review will explore recent advances in the understanding of migraine pathophysiology, and pharmacotherapeutic developments for migraine prevention, with particular emphasis on novel treatments targeted at the calcitonin gene-related peptide (CGRP) pathway.

Neurovascular mechanisms of migraine and cluster headache

Vascular theories of migraine and cluster headache have dominated for many years the pathobiological concept of these disorders. This view is supported by observations that trigeminal activation induces a vascular response and that several vasodilating molecules trigger acute attacks of migraine and cluster headache in susceptible individuals. Over the past 30 years, this rationale has been questioned as it became clear that the actions of some of these molecules, in particular, calcitonin gene-related peptide and pituitary adenylate cyclase-activating peptide, extend far beyond the vasoactive effects, as they possess the ability to modulate nociceptive neuronal activity in several key regions of the trigeminovascular system. These findings have shifted our understanding of these disorders to a primarily neuronal origin with the vascular manifestations being the consequence rather than the origin of trigeminal activation. Nevertheless, the neurovascular component, or coupling, seems to be far more complex than initially thought, being involved in several accompanying features. The review will discuss in detail the anatomical basis and the functional role of the neurovascular mechanisms relevant to migraine and cluster headache.

CGRP and Migraine: The Role of Blocking Calcitonin Gene-Related Peptide Ligand and Receptor in the Management of Migraine

Migraine is a highly prevalent, complex neurological disorder. The burden of disease and the direct/indirect annual costs are enormous. Thus far, treatment options have been inadequate and mostly based on trial and error, leaving a significant unmet need for effective therapies. While the underlying pathophysiology of migraine is incompletely understood, blocking the calcitonin gene-related peptide (CGRP) using monoclonal antibodies targeting CGRP or its receptor and small molecule CGRP receptor antagonists (gepants) have emerged as a promising therapeutic opportunity for the management of migraine. In this review, we discuss new concepts in the pathophysiology of migraine and the role of CGRP, the current guidelines for treating migraine preventively, the medications that are being used, and their limitations. We then discuss small molecule CGRP receptor antagonists, monoclonal antibodies to CGRP ligand and receptor, as well as the detailed results of Phase II and III trials involving these novel treatments. We conclude with a discussion of the implications of blocking CGRP and its receptor.

CGRP ligand and receptor monoclonal antibodies for migraine prevention: Evidence review and clinical implications

Background: Monoclonal antibodies that target calcitonin gene-related peptide or the canonical calcitonin gene-related peptide receptor have emerged as effective and well tolerated for the preventive treatment of migraine. These large molecules appear ideally suited for migraine prevention. They have an extended biological half-life, are administered either monthly or quarterly either by subcutaneous injection or intravenous infusion, require minimal or no dose-titration and have the potential for a rapid onset of effect compared to conventional oral preventive drugs. There is high selectivity and they target an important mediator in the pathogenesis of migraine. Investigation: Phase II and pivotal phase III studies have all yielded positive results with a favorable adverse event profile. No serious treatment-related adverse outcomes have thus far been reported in controlled or long-term open-label extension studies. This tolerability profile promises to improve adherence and, possibly, long-term outcomes. Conclusions: Calcitonin gene-related peptide monoclonal antibodies are effective and well tolerated for the preventive treatment of migraine. They have distinct advantages over currently available oral preventive drugs. While treatment-related serious adverse events have not been observed in open-label extension studies, long-term outcomes and safety will require broad exposure in heterogeneous patient populations in clinical practice. In addition, their safety in women, especially during pregnancy, will require longitudinal surveillance. Given the overlapping mechanism(s), the effectiveness of existing (triptans) and emerging (calcitonin gene-related peptide receptor antagonists) acute therapies in those using a calcitonin gene-related peptide mAb will require further study.

European headache federation guideline on the use of monoclonal antibodies acting on the calcitonin gene related peptide or its receptor for migraine prevention

BACKGROUND AND AIM

Monoclonal antibodies acting on the calcitonin gene-related peptide or on its receptor are new drugs to prevent migraine. Four monoclonal antibodies have been developed: one targeting the calcitonin gene-related peptide receptor (erenumab) and three targeting the calcitonin gene-related peptide (eptinezumab, fremanezumab, and galcanezumab). The aim of this document by the European Headache Federation (EHF) is to provide an evidence-based and expert-based guideline on the use of the monoclonal antibodies acting on the calcitonin gene-related peptide for migraine prevention.

METHODS

The guideline was developed following the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. The working group identified relevant questions, performed systematic review and analysis of the literature, assessed the quality of available evidence, and wrote recommendations. Where the GRADE approach was not applicable, expert opinion was provided.

RESULTS

We found low to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in patients with episodic migraine and medium to high quality of evidence to recommend erenumab, fremanezumab, and galcanezumab in patients with chronic migraine. For several clinical questions, there was not enough evidence to provide recommendations using the GRADE approach and recommendations relied on experts' opinion.

CONCLUSION

Monoclonal antibodies acting on the calcitonin gene-related peptide are new drugs which can be recommended for migraine prevention. Real life data will be useful to improve the use of those drugs in clinical practice.

Emerging drugs for migraine treatment: an update

Introduction: Migraine is a very frequent and disabling neurological disorder. The current treatment options are old, generally poorly tolerated and not migraine-specific, reflecting the low priority of migraine research and highlighting the vast unmet need in its management. Areas covered: Advancement in the understanding of migraine pathophysiological mechanisms and identification of novel potentially meaningful targets have resulted in a multitude of emerging acute and preventive treatments. Here we review the known putative migraine pathophysiological mechanisms in order to understand the rationale of the most promising novel treatments targeting the Calcitonin-Gene-Related Peptide receptor and ligand and the 5 hydroxytryptamine (5-HT)1F receptor. Key findings on the phase II and phase III clinical trials on these treatments will be summarized. Furthermore, a critical analysis on failed trials of potentially meaningful targets such the nitric oxide and the orexinergic pathways will be conducted. Future perspective will be outlined. Expert opinion: The recent approval of Erenumab and Fremanezumab is a major milestone in the therapy of migraine since the approval of triptans. Several more studies are needed to fully understand the clinical potential, long-term safety and cost-effectiveness of these therapies. This paramount achievement should stimulate the development of further research in the migraine field.

From LBR-101 to Fremanezumab for Migraine

Calcitonin gene-related peptide (CGRP) is a neuropeptide of importance in migraine pathogenesis. Its central role in migraine was proven pharmacologically by the development of CGRP receptor antagonists. Monoclonal antibodies targeting CGRP or its receptor are effective in the preventive treatment of episodic and chronic migraine and are considered potential breakthroughs in their treatment. Fremanezumab (previously known as TEV-48125, LBR-101, or RN-307) is a humanized IgG2a monoclonal antibody that binds to CGRP. The development of this antibody validated the role of CGRP in chronic migraine and the drug has been recently approved in the US by the FDA, while it continues to be reviewed by other regulatory agencies. Herein we provide an in-depth review of its development. We start by summarizing its in vitro and in vivo pharmacology, and the phase I studies. We then review the late-stage clinical development, with a focus on its efficacy, safety, similarities, and uniqueness relative to other CGRP antibodies. We close by discussing lessons learned on the mechanisms of migraine and areas for future development and exploration.

Early onset of efficacy with erenumab in patients with episodic and chronic migraine

Background

Subcutaneous erenumab reduced monthly migraine days and increased the likelihood of achieving a ≥ 50% reduction at all monthly assessment points tested in 2 pivotal trials in episodic migraine (EM) and chronic migraine (CM). Early efficacy of migraine preventive medications is an important treatment characteristic to patients. Delays in achievement of efficacy can result in failed adherence. The objective of these post-hoc analyses were to evaluate efficacy in the first 4 weeks after initial subcutaneous administration of erenumab 70 mg, erenumab 140 mg, or placebo.

Methods

There is no generally accepted methodology to measure onset of action for migraine preventive medications. We used a comprehensive approach with data from both studies to evaluate change from baseline in weekly migraine days (WMD), achievement of ≥ 50% reduction in WMD, and proportion of patients experiencing migraine measured on a daily basis. The 7-day moving averages were overlaid with observed data.

Results

In both studies (EM: N = 955; CM: N = 667), there was evidence of onset of efficacy of erenumab vs. placebo during the first week of treatment, which in some cases reached nominal significance. For EM the changes in WMD were (least squares mean [LSM] [95% CI]): placebo, − 0.1 (− 0.3, 0.0); erenumab 70 mg, − 0.3 (− 0.5, − 0.2) p = 0.130; erenumab 140 mg, − 0.6 (− 0.7, − 0.4) p < 0.001. For CM the changes were: placebo, − 0.5 (− 0.8, − 0.3); erenumab 70 mg, − 0.9 (− 1.2, − 0.7) p = 0.047; erenumab 140 mg, − 0.8 (− 1.1, − 0.5) p = 0.18. Achievement of ≥ 50% reduction in WMD was observed as early as Week 1 (adjusted OR [95% CI] erenumab vs placebo) in EM: erenumab 70 mg, 1.3 (1.0, 1.9) p = 0.097; erenumab 140 mg, 2.0 (1.4, 2.7) p < 0.001. A similar outcome was observed for CM: erenumab 70 mg, 1.8 (1.1, 2.8) p = 0.011; erenumab 140 mg, 1.9 (1.2, 2.9) p = 0.009. Seven-day moving averages of observed data showed each treatment arm differed from placebo by Week 1 (OR [95% CI]): in EM Day 3 for erenumab 140 mg, 0.7 (0.5, 1.0) p = 0.031 and at Day 7 for 70 mg, 0.6 (0.4, 0.8) p = 0.002; in CM: Day 6 for erenumab 70 mg, 0.6 (0.4, 0.9) p = 0.022 and at Day 7 for 140 mg, 0.7 (0.4, 1.0); p = 0.038.

Conclusion

Erenumab showed early onset of efficacy with separation from placebo within the first week of treatment in both chronic and episodic migraine patients.

The efficacy and safety of calcitonin gene-related peptide monoclonal antibody for episodic migraine: a meta-analysis

OBJECTIVE

This meta-analysis was performed to evaluate the efficacy and safety of monoclonal antibodies against calcitonin gene-related peptide (CGRP) for episodic migraine prevention.

METHODS

MEDLINE, EMBASE, Web of Science, and the Cochrane Library were searched from inception to April 2018. Studies considered to be eligible were randomized controlled trials about efficacy and safety of calcitonin gene-related peptide monoclonal antibody for episodic migraine prevention.

RESULTS

Eight randomized controlled trials involving 2292 patients were included. The outcomes of this meta-analysis presented that CGRP monoclonal antibodies for preventive treatment of episodic migraine significantly reduced the monthly migraine days from baseline [weighted mean difference (WMD) = - 1.52; 95%CI, - 1.92 to - 1.11; Z = 7.40; P < 0.001] and monthly acute migraine-specific medication consumption from baseline [WMD = - 1.45; 95%CI, - 2.17 to - 0.72; Z = 3.93; P < 0.001], as compared with placebo group. CGRP monoclonal antibodies for preventive treatment of episodic migraine significantly increased the ≥ 50% reduction from baseline in migraine days per month [RR = 1.54; 95%CI, 1.38 to1.71; Z = 7.88; P < 0.001]. The adverse events were similar between the CGRP monoclonal antibody group and placebo group (P = 0.998). The outcomes of subgroup analysis showed that erenumab, galcanezumab, and fremanezumab significantly reduced the monthly migraine days from baseline and increased the ≥ 50% reduction from baseline in migraine days per month. Both erenumab and fremanezumab significantly reduced from baseline.

CONCLUSIONS

Based on the results of this meta-analysis, CGRP monoclonal antibodies significantly reduced the monthly migraine days and acute migraine-specific medication. CGRP monoclonal antibodies were effective and safe for preventive treatment of episodic migraine.

Fremanezumab for preventive treatment of migraine: Functional status on headache-free days

Objective

To evaluate the effect of fremanezumab on the functional status on headache-free days in phase 2 episodic migraine (EM) and chronic migraine (CM) studies.

Methods

Functional status data were collected prospectively via the electronic headache diary on all headache-free days by patients answering questions regarding work/school/household chore performance, speed of work completion, concentration, and feeling of fatigue. Individuals with EM receiving monthly doses of fremanezumab 225 mg (n = 96) or 675 mg (n = 97) or placebo (n = 104) were compared. Individuals with CM receiving fremanezumab 675 mg followed by monthly 225 mg (n = 88) and 900 mg (n = 86) were also independently compared to those receiving placebo (n = 89).

Results

In patients with EM, compared to patients receiving placebo, those receiving fremanezumab experienced an increased number of headache-free days with normal function in work/school/household chore performance and concentration/mental fatigue measures compared to their baseline over the entire treatment period (all p < 0.005). An increased number of headache-free days with normal functional performance for some measures was also found in the CM group in those treated with fremanezumab.

Conclusion

There was an increased number of headache-free days with normal functional performance on all measures for the patients with EM and some measures for patients with CM in the fremanezumab-treated groups. Further research is required to confirm these findings in a prospective study and to clarify the underlying mechanism(s).

ClinicalTrials.gov identifier:

NCT02025556 and NCT02021773.

Classification of evidence

This study provides Class II evidence that for patients with migraine, fremanezumab increases normal functional performance on headache-free days.

New strategies for the treatment and prevention of primary headache disorders

The primary headache disorders, which include migraine, cluster headache and tension-type headache, are among the most common diseases and leading causes of disability worldwide. The available treatment options for primary headache disorders have unsatisfactory rates of efficacy, tolerability and patient adherence. In this Review, we discuss promising new approaches for the prevention of primary headache disorders, such as monoclonal antibodies targeting calcitonin gene-related peptide (CGRP) or its receptor, and small-molecule CGRP receptor antagonists. Neuromodulation approaches employing noninvasive or implantable devices also show promise for treating primary headache disorders. Noninvasive treatments, such as transcranial magnetic stimulation and transcutaneous peripheral nerve stimulation, are delivered by devices that patients can self-administer. Implantable devices targeting the occipital nerves, sphenopalatine ganglion or high cervical spinal cord are placed using percutaneous and/or surgical procedures, and are powered either wirelessly or by surgically implanted batteries. These new and emerging treatments have the potential to address unmet patient needs and reduce headache-associated disability.

Calcitonin Gene-Related Peptide-Targeted Therapies for Migraine and Cluster Headache: A Review

Calcitonin gene-related peptide (CGRP) is a signaling neuropeptide released from activated trigeminal sensory afferents in headache and facial pain disorders. There are a handful of CGRP-targeted therapies currently in phase 3 studies for migraine acute treatment or prevention. Currently, 4 monoclonal antibodies targeting either the CGRP ligand or receptor are being studied for migraine prevention: ALD403 (eptinezumab), AMG 334 (erenumab), LY2951742 (galcanezumab), and TEV-48125 (fremanezumab). Meanwhile, 1 small-molecule CGRP receptor antagonist (ubrogepant, MK-1602) is currently in phase 3 studies for the acute treatment of migraine. Two of these anti-CGRP monoclonal antibodies are in clinical trials for cluster headache prevention as well. Several other small-molecular CGRP receptor antagonists are in earlier stages of development for acute migraine treatment or prevention. In this review, we will discuss the growing body of clinical trials studying CGRP-targeted therapies for migraine and cluster headache.

The Biology of Monoclonal Antibodies: Focus on Calcitonin Gene-Related Peptide for Prophylactic Migraine Therapy

Calcitonin gene-related peptide (CGRP) is 37-amino-acid neuropeptide, crucially involved in migraine pathophysiology. Four monoclonal antibodies (mAbs) targeting the CGRP pathway are currently under evaluation for the prevention of episodic and chronic migraine: eptinezumab (ALD403), fremanezumab (TEV-48125), galcanezumab (LY2951742), and erenumab (AMG334). As reviewed in this article, all 4 antibodies have been proven effective, tolerable, and safe as migraine prophylactic treatments in phase II clinical trials. The mean decrease in migraine days per month was between 3.4 and 6.3 days/month after 8 to 12 weeks of treatment, and the placebo subtracted benefit ranged from 1 to 2.18 days. Notably, up to 32% of subjects experienced total migraine freedom after drug administration. Substance class-specific adverse events and treatment-related serious adverse event did not occur. Further long-term and large-scale trials are currently under way to verify the safety and efficacy profile of mAbs. In particular, the potential risk of vascular adverse events and the role of anti-drug antibodies deserve special attention. Anti-CGRP peptide and anti-CGRP receptor antibodies are the first effective treatments, which were specifically developed for the prevention of migraine. Their site of action in migraine prevention is most likely peripheral due to large molecule size, which prevents the penetration through the blood-brain barrier and thereby shows that peripheral components play a pivotal role in the pathophysiology of a CNS disease.