Safety and tolerability of atogepant for the preventive treatment of migraine: a post hoc analysis of pooled data from four clinical trials

BACKGROUND

Conventional, non-specific preventive migraine treatments often demonstrate low rates of treatment persistence due to poor efficacy or tolerability. Effective, well-tolerated preventive treatments are needed to reduce migraine symptoms, improve function, and enhance quality of life. Atogepant is a migraine-specific oral calcitonin gene-related peptide receptor antagonist that is indicated for the preventive treatment of migraine in adults. This analysis evaluated the safety and tolerability profile of atogepant for the preventive treatment of migraine, including adverse events (AEs) of interest, such as constipation, nausea, hepatic safety, weight changes, and cardiac disorders.

METHODS

This post hoc analysis was performed using data pooled from 2 (12-week) randomized, double-blind, placebo-controlled trials (RCTs) and 2 (40- and 52-week) open-label long-term safety (LTS) trials of oral atogepant for episodic migraine (EM).

RESULTS

The safety population included 1550 participants from the pooled RCTs (atogepant, n = 1142; placebo, n = 408) and 1424 participants from the pooled LTS trials (atogepant, n = 1228; standard care [SC], n = 196). In total, 643/1142 (56.3%) atogepant participants and 218/408 (53.4%) placebo participants experienced ≥ 1 treatment-emergent AEs (TEAEs) in the RCTs. In the LTS trials, 792/1228 (64.5%) of atogepant participants and 154/196 (78.6%) of SC participants experienced ≥ 1 TEAEs. The most commonly reported TEAEs (≥ 5%) in participants who received atogepant once daily were upper respiratory tract infection (5.3% in RCTs, 7.7% in LTS trials), constipation (6.1% in RCTs, 5.0% in LTS trials), nausea (6.6% in RCTs, 4.6% in LTS trials), and urinary tract infection (3.4% in RCTs, 5.2% in LTS trials). Additionally, weight loss appeared to be dose- and duration-dependent. Most TEAEs were considered unrelated to study drug and few led to discontinuation.

CONCLUSIONS

Overall, atogepant is safe and well tolerated in pooled RCTs and LTS trials for the preventive treatment of EM in adults.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers: NCT02848326 (MD-01), NCT03777059 (ADVANCE), NCT03700320 (study 302), NCT03939312 (study 309).

Safety and Efficacy of Calcitonin Gene-related Peptide Receptor Antagonists and Selective Serotonin Receptor Agonist in the Management of Migraine: A Systematic Review and Meta-analysis

BACKGROUND

Recently, US Food and Drug Administration (FDA) has approved calcitonin gene-related peptide receptor antagonists (rimegepant, and ubrogepant), and selective serotonin receptor agonists (lasmiditan) in the management of migraine. However, the exact safety and efficacy profile of these drugs is unclear so far.

METHODS

The study's primary objective was to determine the exact safety and efficacy profile. The overall estimate was calculated in terms of risk ratios using a suitable model. The subgroup analysis was also performed to check the effect of individual drugs on the outcome, whereas sensitivity analysis was performed to check the effects of outliers on the outcome. All the analyses were performed using Rev Man 5. The drugs have shown significant improvement in efficacy parameters (pain freedom, most bothersome symptoms, phonophobia, nausea, and photophobia).

RESULTS

The subgroup analysis results have shown significant improvement in all efficacy parameters in the rimegepant and ubrogepant groups. The effect of ubrogepant on safety parameters was found to be non-significant, indicating a better safety profile of ubrogepant than lasmiditan.

CONCLUSION

The sensitivity analysis results have shown no effect of outliers on the efficacy parameters. Based on the available evidence, recently approved drugs are effective in the treatment of migraine, however, associated with few adverse drug reactions.

Fifty years of pain research and clinical advances: highlights and key trends

ABSTRACT

This article highlights advances in basic science preclinical pain research, clinical research, and psychological research occurring over the 50 years since the International Association for the Study of Pain was founded. It presents important findings and key trends in these 3 areas of pain science: basic science preclinical research, clinical research, and psychological research.

Calcitonin Gene-Related Peptide Monoclonal Antibodies and Risk of SARS-CoV-2 Infection and Severe COVID-19 Outcomes Among Veterans With Migraine Disorder

Importance

Calcitonin gene-related peptide (CGRP), a neuropeptide involved in migraine pathophysiology, is also a key neuroimmune modulator. CGRP antagonists may help mitigate the hyperinflammatory response observed in patients with COVID-19; however, findings from the literature are contradictory, and to date, no study has investigated the safety and effectiveness of CGRP antagonists against COVID-19.

Objective

To evaluate the association between CGRP monoclonal antibody (mAb) treatment and risk of SARS-CoV-2 infection and sequela hospitalization, requiring supplemental oxygen, use of mechanical ventilation, or death.

Design, Setting, and Participants

This retrospective cohort study analyzed the electronic health records of US veterans aged 18 to 65 years who were diagnosed with migraine disorder and were at risk of COVID-19 between January 20, 2020, and May 19, 2022.

Exposure

Initiation of CGRP mAbs.

Main Outcomes and Measures

The main outcome was cumulative incidence of SARS-CoV-2 infection. Odds of 30-day hospitalization, requiring supplemental oxygen, use of mechanical ventilation, or death were secondary outcomes.

Results

Among 8 178 652 eligible person-trials (354 294 veterans), 9992 (mean [SD] age, 46.0 [9.5] years; 53.9% male) initiated CGRP mAbs and 8 168 660 (mean [SD] age, 46.6 [10.2] years; 65.7% male) did not initiate CGRP mAbs. Over a 28-month follow-up period, 1247 initiators (12.5%) and 780 575 noninitiators (9.6%) tested positive for SARS-CoV-2. After censoring persons who deviated from treatment, the incidence was 7.4 cases per 1000 person-months among initiators and 6.9 per 1000 person-months among noninitiators. The inverse probability-weighted observational analogs of intention-to-treat and per-protocol hazard ratios were 0.95 (95% CI, 0.89-1.01) and 0.93 (95% CI, 0.86-1.02), respectively. No significant differences in the likelihood of hospitalization (odds ratio [OR], 0.93; 95% CI, 0.62-1.41), requiring supplemental oxygen (OR, 0.77; 95% CI, 0.45-1.30), use of mechanical ventilation (OR, 0.85; 95% CI, 0.26-2.84), or death (OR, 0.67; 95% CI, 0.09-5.23) were observed between CGRP mAb initiators and noninitiators who tested positive for SARS-CoV-2.

Conclusions and Relevance

In this cohort study, CGRP mAb treatment was not associated with positive SARS-CoV-2 test results or risk of severe COVID-19 outcomes, suggesting that CGRP mAbs may be used for migraine prevention during the COVID-19 pandemic. Given the few events of requiring supplemental oxygen, use of mechanical ventilation, and death, replication analysis in a larger sample of patients later in the course of disease is warranted.

Migraine Pathophysiology Revisited: Proposal of a New Molecular Theory of Migraine Pathophysiology and Headache Diagnostic Criteria

Various explanations for the pathophysiology of migraines have been proposed; however, none of these provide a complete explanation. The author critically reviews previous theories and proposes a new molecular theory of migraine pathophysiology. The diagnosis of primary headaches is generally based on clinical histories and symptoms only because there is no reliable diagnostic examination. The author proposes a new classification system and set of diagnostic criteria for headaches based on molecular markers.

CGRP and PACAP-38 play an important role in diagnosing pediatric migraine

Background

An increasing number of studies have suggested that the important role of vasoactive peptides, such as pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) and calcitonin gene-related peptide (CGRP), in the pathophysiology of migraine seems undeniable in adults, but studies in pediatric migraine patients remain scarce. We prospectively investigated CGRP and PACAP-38 plasma levels in children with migraine during ictal and interictal periods and compared the results between migraine patients with aura and without aura. We were the first to explore the diagnostic value of a combination of CGRP and PACAP-38.

Methods

Seventy-six migraine patients aged 4–18 years and seventy-seven age-matched healthy children were included in the study. Plasma vasoactive peptides were measured using the enzyme-linked immunosorbent assay (ELISA). Differences and correlations of groups were analyzed using the independent samples t-test, analysis of variance (ANOVA), Mann-Whitney U test, and multiple linear regression. We also performed logistic regression and receiver operating characteristic curve (ROC) analyses to evaluate the diagnostic value of CGRP and PACAP-38 in pediatric migraine.

Results

PACAP-38 and CGRP levels in migraine patients during the ictal and interictal periods were higher than those in controls (p < 0.001). PACAP-38 and CGRP levels in migraine patients with aura and without aura were higher than those in controls (p < 0.001). PACAP-38 and CGRP were independent risk factors in diagnosing pediatric migraine (adjusted OR (PACAP-38) =1.331, 95% CI: 1.177–1.506, p < 0.001; adjusted OR (CGRP) = 1.113, 95% CI: 1.064–1.165, p < 0.001). Area Under Curve (AUC) comparison: Combination (0.926) > CGRP (0.869) > PACAP-38 (0.867).

Conclusions

Our study found almost the same changes in CGRP and PACAP levels in pediatric migraine, suggesting that CGRP and PACAP-38 may work together to play an integral role in pediatric migraine. Higher CGRP levels were found in the ictal phase than in the interictal phase and with aura group than without aura group, indicating that CGRP may take part in the formation of pain and aura. Moreover, ROC and logistic regression analyses suggested that CGRP and PACAP-38 are good indicators to diagnose pediatric migraine, and the combination of CGRP and PACAP-38 was valuable in diagnosing pediatric migraine and differentiating pediatric migraine from non-migraine headaches.

Trial registration

The study has been registered at the Chinese Clinical Trial Registry (ChiCTR2100043157).

Brazilian descriptive study of 104 consecutive real-world migraine patients treated with monoclonal antibodies

BACKGROUND

Migraine is a highly disabling and prevalent neurological disorder. A peptide, calcitonin gene-related peptide, was identified as involved in migraine pathophysiology and monoclonal anti-CGRP antibodies have been developed.

AIM

To describe the clinical characteristics and therapeutic response of migraine patients treated with monoclonal antibodies.

METHOD

An observational, prospective, uncontrolled and descriptive study was carried out with a sample of 112 consecutive patients with episodic or chronic migraine treated with monoclonal antibodies. Eight patients did not return for the following medical consultation. They were excluded from the study.

RESULTS

A total of 104 patients were described. There was a predominance of episodic migraine. Before treatment, the average frequency of headache was 15.3±8.5 days per month, during the previous three months. Monoclonal antibodies were prescribed at the following frequency: erenumab (49%), galcanezumab (45.2%), and fremanezumab (5.8%). After the third month, the reduction in headache attacks was greater than 50% in 57.7% of patients. Adverse events were referred by 18.3% of patients, in this order of frequency: constipation (7.7%), insomnia (2.9%), vertigo (1.9%), erythema at the injection site (1.9%), arthralgia (1%), nasopharyngitis (1%), facial and hand edema (1%), irritation at the injection site (1%), and paresthesia at the injection site (1%).

CONCLUSIONS

This described analysis of migraine patients who used monoclonal antibodies presented one of the first Brazilian experiences with real-world patients. Our results may enlighten clinicians on the outcomes and ways of prescribing anti-CGRP antibodies.

Comparison of New Pharmacologic Agents With Triptans for Treatment of Migraine: A Systematic Review and Meta-analysis

IMPORTANCE

New therapeutic classes of migraine-specific treatment have been developed, including 5-hydroxytryptamine1F receptor agonists (lasmiditan) and calcitonin gene-related peptide antagonists (rimegepant and ubrogepant).

OBJECTIVE

To compare outcomes associated with the use of lasmiditan, rimegepant, and ubrogepant vs triptans for acute management of migraine headaches.

DATA SOURCES

The Cochrane Register of Controlled Trials, Embase, and PubMed were searched from inception to March 5, 2020.

STUDY SELECTION

Double-blind randomized clinical trials examining current available migraine-specific acute treatments were included.

DATA EXTRACTION AND SYNTHESIS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was applied to extract the data according to a predetermined list of variables of interest, and all network meta-analyses were conducted using a random-effects model.

MAIN OUTCOMES AND MEASURES

The primary outcome was the odds ratio (OR) for freedom from pain (hereafter referred to as pain freedom) at 2 hours after the dose, and the secondary outcomes were ORs for pain relief at 2 hours after the dose and any adverse events.

RESULTS

A total of 64 randomized clinical trials were included (46 442 participants; 74%-87% women; age range, 36-43 years). Most of the included treatments were associated with reduced pain at 2 hours compared with placebo. Most triptans were associated with higher ORs for pain freedom at 2 hours compared with lasmiditan (range: OR, 1.72 [95% CI, 1.06-2.80] to OR, 3.40 [95% CI, 2.12-5.44]), rimegepant (range: OR, 1.58 [95% CI, 1.07-2.33] to OR, 3.13 [95% CI, 2.16-4.52]), and ubrogepant (range: OR, 1.54 [95% CI, 1.00-2.37] to OR, 3.05 [95% CI, 2.02-4.60]). Most triptans were associated with higher ORs for pain relief at 2 hours compared with lasmiditan (range: OR, 1.46 [95% CI, 1.09-1.96] to OR, 3.31 [95% CI, 2.41-4.55]), rimegepant (range: OR, 1.33 [95% CI, 1.01-1.76] to OR, 3.01 [95% CI, 2.33-3.88]), and ubrogepant (range: OR, 1.38 [95% CI, 1.02-1.88] to OR, 3.13 [95% CI, 2.35-4.15]). The comparisons between lasmiditan, rimegepant, and ubrogepant were not statistically significant for both pain freedom and pain relief at 2 hours. Lasmiditan was associated with the highest risk of any adverse events, and certain triptans (rizatriptan, sumatriptan, and zolmitriptan) were also associated with a higher risk of any adverse events than the calcitonin gene-related peptide antagonists.

CONCLUSIONS AND RELEVANCE

For pain freedom or pain relief at 2 hours after the dose, lasmiditan, rimegepant, and ubrogepant were associated with higher ORs compared with placebo but lower ORs compared with most triptans. However, the lack of cardiovascular risks for these new classes of migraine-specific treatments may offer an alternative to triptans.

Atogepant for the Preventive Treatment of Migraine

BACKGROUND

Atogepant is an oral, small-molecule, calcitonin gene-related peptide receptor antagonist that is being investigated for the preventive treatment of migraine.

METHODS

In a phase 3, double-blind trial, we randomly assigned adults with 4 to 14 migraine days per month in a 1:1:1:1 ratio to receive a once-daily dose of oral atogepant (10 mg, 30 mg, or 60 mg) or placebo for 12 weeks. The primary end point was the change from baseline in the mean number of migraine days per month across the 12 weeks. Secondary end points included headache days per month, a reduction from baseline of at least 50% in the 3-month average of migraine days per month, quality of life, and scores on the Activity Impairment in Migraine-Diary (AIM-D).

RESULTS

A total of 2270 participants were screened, 910 were enrolled, and 873 were included in the efficacy analysis; 214 were assigned to the 10-mg atogepant group, 223 to the 30-mg atogepant group, 222 to the 60-mg atogepant group, and 214 to the placebo group. The mean number of migraine days per month at baseline ranged from 7.5 to 7.9 in the four groups. The changes from baseline across 12 weeks were -3.7 days with 10-mg atogepant, -3.9 days with 30-mg atogepant, -4.2 days with 60-mg atogepant, and -2.5 days with placebo. The mean differences from placebo in the change from baseline were -1.2 days with 10-mg atogepant (95% confidence interval [CI], -1.8 to -0.6), -1.4 days with 30-mg atogepant (95% CI, -1.9 to -0.8), and -1.7 days with 60-mg atogepant (95% CI, -2.3 to -1.2) (P<0.001 for all comparisons with placebo). Results for the secondary end points favored atogepant over placebo with the exceptions of the AIM-D Performance of Daily Activities score and the AIM-D Physical Impairment score for the 10-mg dose. The most common adverse events were constipation (6.9 to 7.7% across atogepant doses) and nausea (4.4 to 6.1% across atogepant doses). Serious adverse events included one case each of asthma and optic neuritis in the 10-mg atogepant group.

CONCLUSIONS

Oral atogepant once daily was effective in reducing the number of migraine days and headache days over a period of 12 weeks. Adverse events included constipation and nausea. Longer and larger trials are needed to determine the effect and safety of atogepant for migraine prevention. (Funded by Allergan; ADVANCE ClinicalTrials.gov number, NCT03777059.).

Acute Treatment of Migraine: What has Changed in Pharmacotherapies?

Background

Migraine is the most prevalent neurological disorder and the leading cause of disability in individuals under 50 years of age. Two types of migraine therapies have been defined: acute therapy (abortive or symptomatic treatment), the purpose of which is to interrupt migraine attacks, and preventive treatment (prophylactic treatment), the purpose of which is to reduce the frequency and severity of migraine attacks.

Objective

This paper reviews research advances in new agents for acute therapy of migraine.

Material and Methods

This review provides an overview of emerging new drugs for acute treatment of migraine based on clinical evidence and summarizes the milestones of different stages of clinical development.

Results

Two new formulations of sumatriptan, DFN-11 (3 mg doses of subcutaneous sumatriptan) and DFN-02 (a nasal spray of sumatriptan 10 mg and a permeation-enhancing excipient), have been developed, and both of them showed a fast-onset action with efficacy for acute treatment of migraine with fewer adverse events. New drug discovery programs shifted the focus to the development of ditans, a group of antimigraine drugs targeting 5-HT_1F receptors. Only lasmiditan has progressed to phase III clinical trials and was finally approved by the Food and Drug Administration (FDA) for acute migraine treatment. The other target for acute therapy is CGRP receptor antagonists, namely, gepants. Ubrogepant and rimegepant demonstrated statistically significant efficacy, and both were recently approved by the FDA. These 5-HT_1F receptor agonists and CGRP receptor antagonists did not cause vasoconstriction, offering advantages over the current mainstay of specific acute migraine treatment.

Conclusions

Overall, these new agents have expanded the available acute therapies for migraine treatment and will likely change the strategy with which we treat patients with migraine in the future.

Safety and efficacy of ubrogepant in participants with major cardiovascular risk factors in two single-attack phase 3 randomized trials: ACHIEVE I and II

OBJECTIVE

To examine the safety and efficacy of ubrogepant for acute treatment of migraine across cardiovascular (CV) disease risk categories.

METHODS

ACHIEVE I and II were multicenter, double-blind, single-attack, phase 3 trials in adults with migraine, with or without aura. Participants were randomized 1:1:1 to placebo or ubrogepant (50 or 100 mg in ACHIEVE I; 25 or 50 mg in ACHIEVE II), to treat one migraine attack of moderate or severe headache pain intensity. This post-hoc analysis pooled data from ubrogepant 50 mg and placebo groups from the ACHIEVE trials to examine the safety and efficacy of ubrogepant by baseline cardiovascular disease risk factors. Using a cardiovascular risk assessment algorithm, participants were categorized as having no cardiovascular risk, low cardiovascular risk or moderate-high cardiovascular risk at baseline. Treatment-emergent adverse events were documented 48 h and 30 days after taking the trial medication. Co-primary efficacy outcomes were 2-h pain freedom and 2-h absence of most bothersome migraine-associated symptom.

RESULTS

Overall, 3358 participants were randomized in the ACHIEVE trials (n = 2901 safety population; n = 2682 modified intent-to-treat population). In the safety population, 11% of participants were categorized as moderate-high (n = 311), 32% low (n = 920), and 58% no cardiovascular risk factors (n = 1670). The proportion of ubrogepant participants reporting a treatment-emergent adverse event was comparable across risk categories and similar to placebo. The treatment effects of ubrogepant versus placebo were consistent across cardiovascular risk categories for all efficacy outcomes.

CONCLUSION

The safety and efficacy of ubrogepant for the acute treatment of a single migraine attack did not differ by the presence of major cardiovascular risk factors. No evidence of increased treatment-emergent adverse events or cardiac system organ class adverse events with ≥2 major cardiovascular risk factors and no safety concerns were identified.Trial Registration: ACHIEVE I ClinicalTrials.gov number, NCT02828020; ACHIEVE II ClinicalTrials.gov number, NCT02867709.

Pain pharmacogenetics

Pain is a significant problem in medicine. The use of PGx markers to personalize postoperative analgesia can increase its effectiveness and avoid undesirable reactions. This article describes the mechanisms of nociception and antinociception and shows the pathophysiological mechanisms of pain in the human body. The main subject of this article is pharmacogenetic approach to the selection of anesthetics. Current review presents data for local and general anesthetics, opioids, and non-steroidal anti-inflammatory drugs. None of the anesthetics currently has clinical guidelines for pharmacogenetic testing. This literature review summarizes the results of original research available, to date, and draws attention to this area.

Migraine and Sleep in Children: A Bidirectional Relationship

Migraine and sleep disorders in children exhibit a bidirectional relationship. This relationship is based on shared pathophysiology. Migraine involves activation of the trigeminal vascular system. Nociceptive neurons that innervate the dura release various vasoactive peptides. Calcitonin gene-related peptide is the most active of these peptides. Neural pathways that are involved in sleep generation are divided into those responsible for circadian rhythm, wake promotion, non-rapid eye movement, and rapid eye movement sleep activation. Sleep state switches are a critical component of these systems. The cerebral structures, networks, and neurochemical systems that are involved in migraine align closely with those responsible for the regulation of sleep. Neurochemical systems that are involved with both the pathogenesis of migraine and regulation of sleep include adenosine, melatonin, orexin, and calcitonin gene-related peptide. Sleep disorders represent the most common comorbidity with migraine in childhood. The prevalence of parasomnias, obstructive sleep apnea, and sleep-related movement disorders is significantly greater in children migraineurs. Infantile colic is a precursor of childhood migraine. Treatment of comorbid sleep disorders is important for the appropriate management of children with migraine. Sleep-based behavioral interventions can be of substantial benefit. These interventions are particularly important in children due to limited evidence for effective migraine pharmacotherapy.

Gepants for abortive treatment of migraine: A network meta-analysis

OBJECTIVES

To evaluate and compare the efficacy and safety of gepants for abortive treatment of migraine by network meta-analysis.

MATERIALS & METHODS

Publications, which were randomized controlled trials (RCTs) about gepants for abortive treatment of migraine, were acquired from Pubmed and Cochrane Library. The literatures screening and quality assessment followed the Cochrane handbook. Review manager 5.3 and Addis v1.16.8 were utilized for data analyzing.

RESULTS

Totally, 15 RCTs were included in the network meta-analysis. The trials enrolled were with high quality. There are 7 treatments were analyzed: BI 44370 TA, MK-3207, olcegepant, rimegepant, telcagepant, ubrogepant, and placebo. Of these trials, 11,118 patients and 10,917 patients were assigned to one of 7 treatments randomly for efficacy assessment and safety assessment, respectively. In meta-analysis of direct comparisons, all gepants were superior to placebo in achieving pain freedom 2 hr postdose and only rimegepant and telcagepant were higher than placebo in incidence of any adverse events. In network meta-analysis, the rank best 3 drugs were olcegepant, BI 44370 TA, and MK-3207 for efficacy outcomes. And the rank best 3 drugs were BI 44370 TA, placebo, and ubrogepant for safety outcomes.

CONCLUSION

Gepants were effective for abortive treatment of migraine. The most effective treatment of gepants for migraine might be olcegepant which were administrated transvenously. And all of gepants were safe for migraine treatment with single dose.

NO up-regulates migraine-related CGRP via activation of an Akt/GSK-3β/NF-κB signaling cascade in trigeminal ganglion neurons

The release of the neuropeptide CGRP from the trigeminal ganglion neurons (TGNs) plays a central role in migraine. Whereas CGRP can activate NO release from ganglionic glial cells, NO in turn enhances CGRP release. However, it remains unclear how NO promotes CGRP release. Here, we report that the NO donor SNAP triggered CGRP release from cultured primary TGNs. This event was associated with GSK-3β activation and Akt inactivation. Immunofluorescent staining revealed that GSK-3β primarily located in neurons. Furthermore, GSK-3β inhibition resulted in a marked reduction in expression of CGRP as well as other migraine-related factors, including substance P, cholecystokinin, and prostaglandin E2. Last, exposure to SNAP also activated NF-κB, while NF-κB inhibition prevented the induction of CGRP by SNAP. Interestingly, this event was blocked by GSK-3β inhibition, in association with inhibition of NF-κB/p65 expression and nuclear translocation. Together, these findings argue that NO could stimulate TGNs to release of CGRP as well as other migraine-related factors, likely by activating GSK-3β, providing a novel mechanism underlying a potential feed-forward loop between NO and CGRP in migraine. They also raise a possibility that GSK-3β might act to trigger migraine through activation of NF-κB, suggesting a link between neuroinflammation and migraine.

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.

The need for new acutely acting antimigraine drugs: moving safely outside acute medication overuse

Background

The treatment of migraine is impeded by several difficulties, among which insufficient headache relief, side effects, and risk for developing medication overuse headache (MOH). Thus, new acutely acting antimigraine drugs are currently being developed, among which the small molecule CGRP receptor antagonists, gepants, and the 5-HT_1F receptor agonist lasmiditan. Whether treatment with these drugs carries the same risk for developing MOH is currently unknown.

Main body

Pathophysiological studies on MOH in animal models have suggested that decreased 5-hydroxytryptamine (5-HT, serotonin) levels, increased calcitonin-gene related peptide (CGRP) expression and changes in 5-HT receptor expression (lower 5-HT_1B/D and higher 5-HT_2A expression) may be involved in MOH. The decreased 5-HT may increase cortical spreading depression frequency and induce central sensitization in the cerebral cortex and caudal nucleus of the trigeminal tract. Additionally, low concentrations of 5-HT, a feature often observed in MOH patients, could increase CGRP expression. This provides a possible link between the pathways of 5-HT and CGRP, targets of lasmiditan and gepants, respectively. Since lasmiditan is a 5-HT_1F receptor agonist and gepants are CGRP receptor antagonists, they could have different risks for developing MOH because of the different (over) compensation mechanisms following prolonged agonist versus antagonist treatment.

Conclusion

The acute treatment of migraine will certainly improve with the advent of two novel classes of drugs, i.e., the 5-HT_1F receptor agonists (lasmiditan) and the small molecule CGRP receptor antagonists (gepants). Data on the effects of 5-HT_1F receptor agonism in relation to MOH, as well as the effects of chronic CGRP receptor blockade, are awaited with interest.