Calcitonin Gene-Related Peptide Receptor Antagonists (Gepants) for the Acute Treatment of Nausea in Episodic Migraine: A Systematic Review and Meta-Analysis

Calcitonin gene-related peptide receptor antagonism reduces motion sickness indicators in mouse migraine models

BACKGROUND

Migraine and vestibular migraine are disorders associated with a heightened motion sensitivity that provoke symptoms of motion-induced nausea and motion sickness. VM affects ∼3% of adults in the USA and affects three-fold more women than men. Triptans (selective serotonin receptor agonists) relieve migraine pain but lack efficacy for vertigo. Murine models of photophobia and allodynia have used injections of calcitonin gene-related peptide (CGRP) or other migraine triggers, such as sodium nitroprusside (SNP), to induce migraine sensitivities in mice to touch and light. Yet, there is limited research on whether these triggers affect motion-induced nausea in mice, and whether migraine blockers can reduce these migraine symptoms. We hypothesized that systemic delivery of CGRP or SNP will increase motion sickness susceptibility and motion-induced nausea in mouse models, and that migraine blockers can block these changes induced by systemically delivered CGRP or SNP.

METHODS

We investigated two measures of motion sickness assessment [motion sickness index (MSI) scoring and motion-induced thermoregulation] after intraperitoneal injections of either CGRP or SNP in C57BL/6J mice. The drugs olcegepant, sumatriptan and rizatriptan were used to assess the efficacy of migraine blockers.

RESULTS

MSI measures were confounded by CGRP's effect on gastric distress. However, analysis of tail vasodilatations as a surrogate for motion-induced nausea was robust for both migraine triggers. Only olcegepant treatment rescued tail vasodilatations.

CONCLUSIONS

These preclinical findings support the use of small molecule CGRP receptor antagonists for the treatment of motion-induced nausea of migraine, and show that triptan therapeutics are ineffective against motion-induced nausea of migraine.Trial Registration: Not Applicable.

Pathophysiology and Therapy of Associated Features of Migraine

Migraine is a complex and debilitating disorder that is broadly recognised by its characteristic headache. However, given the wide array of clinical presentations in migraineurs, the headache might not represent the main troublesome symptom and it can even go unnoticed. Understanding migraines exclusively as a pain process is simplistic and certainly hinders management. We describe the mechanisms behind some of the most disabling associated symptoms of migraine, including the relationship between the central and peripheral processes that take part in nausea, osmophobia, phonophobia, vertigo and allodynia. The rationale for the efficacy of the current therapeutic arsenal is also depicted in this article. The associated symptoms to migraine, apart from the painful component, are frequent, under-recognised and can be more deleterious than the headache itself. The clinical anamnesis of a headache patient should enquire about the associated symptoms, and treatment should be considered and individualised. Acknowledging the associated symptoms as a fundamental part of migraine has permitted a deeper and more coherent comprehension of the pathophysiology of migraine.

Peripheral N-methyl-D-aspartate receptor activation contributes to monosodium glutamate-induced headache but not nausea behaviours in rats

Monosodium glutamate induces behaviors thought to reflect headache and nausea in rats. We explored the effects of the N-methyl-d-aspartate receptor antagonist (2R)-amino-5-phosphonovaleric acid, the inotropic glutamate receptor antagonist kynurenic acid, and the CGRP receptor antagonist olcegepant, on monosodium glutamate-induced increases in nocifensive, headache-like and nausea behaviours. Effects of these antagonists on motor function were examined with a rotarod. The effect of the dopamine receptor antagonist metoclopramide and the serotonin 3 receptor antagonist ondansetron on nausea behaviour was also assessed. (2R)-amino-5-phosphonovaleric acid, and to a lesser extent, kynurenic acid and olcegepant, reduced nocifensive and headache-like behaviours evoked by monosodium glutamate. No alteration in motor function by (2R)-amino-5-phosphonovaleric acid, kynurenic acid or olcegepant was observed. No sex-related differences in the effectiveness of these agents were identified. Nausea behaviour was significantly more pronounced in male than in female rats. Olcegepant, ondansetron and metoclopramide ameliorated this nausea behaviour in male rats. Ondansetron and metoclopramide also reduced headache-like behaviour in male rats. These findings suggest that peripheral N-methyl-d-aspartate receptor activation underlies monosodium glutamate-induced headache-like behaviour but does not mediate the nausea behaviour in rats.

Safety evaluation of oral calcitonin-gene-related peptide receptor antagonists in patients with acute migraine: a systematic review and meta-analysis

OBJECTIVE

Calcitonin gene-related peptide (CGRP) receptor antagonists have been suggested as novel treatments for acute migraine. This study aimed to use meta-analysis to compare the safety and tolerability of five existing oral CGRP receptor antagonists (BI44370TA, MK-3207, rimegepant, telcagepant, and ubrogepant) with that of a placebo or triptans against acute migraine.

METHODS

Five prominent databases were searched to identify randomized controlled trials on this topic. The primary safety outcomes of interest were any adverse events (AEs) and treatment-related adverse events (TRAEs), and secondary outcomes were individual events, namely diarrhea, dizziness, dry mouth, fatigue, nausea, paresthesia, somnolence, upper abdominal pain, and vomiting.

RESULTS

Fifteen studies met the eligibility criteria and were examined in detail. Although, compared to placebo, oral CGRP receptor antagonists significantly increased the incidence of any AEs (risk ratio [RR] = 1.15; 95% confidence interval [CI] = 1.07-1.23), there was no difference in the incidence of TRAEs (RR = 1.18; 95% CI = 1.00-1.38). Moreover, CGRP receptor antagonists were safer than triptans with respect to primary safety outcomes, such as any AEs (RR = 0.78; 95% CI = 0.63-0.98) and TRAEs (RR = 0.68; 95% CI = 0.58-0.79).

CONCLUSION

Despite oral CGRP receptor antagonists posing a significantly higher risk of AEs when compared to placebo, CGRP receptor antagonists have a favorable safety profile compared to triptans. Our findings inform strategies to enhance safety and tolerability in the treatment of acute migraine.

CGRP and CGRP-receptor as targets of migraine therapy: Brain Prize-2021

BACKGROUND

Migraine is a highly prevalent primary headache with an unclear pathomechanism. During the last 40 years numerous hypotheses have arisen, among them the theory of the trigeminovascular system is the primary one. It serves as a skeleton in successful preclinical studies and in the development of effective therapeutic options for migraine headache.

OBJECTIVE

The Brain Prize (awarded annually by the Lundbeck Foundation) is the most prestigious tribute in neuroscience. The winners in 2021 were Lars Edvinsson, Peter Goadsby, Michael Moskowitz and Jes Olesen. They are the fathers of the migraine pathomechanism which led to revolutionary new treatments. This review summarizes their landmark findings.

METHODS

Data related to this topic were reviewed from PubMed records published between 1979 and May 2021. Searches were based on preclinical and clinical studies in the covered field. The findings were listed in chronological order. From a therapeutic perspective, only randomized controlled trials and meta-analysis were discussed.

RESULTS

The calcitonin gene-related peptide-related pathogenesis of migraine is based on the activation of the trigeminovascular system. The therapeutic triad for migraine is triptans, gepants and calcitonin gene-related peptide-targeted monoclonal antibodies.

CONCLUSION

In the past 40 years, the systematic work of leading headache scientists has resulted in robust theoretical and therapeutic knowledge in the preclinical and clinical study of migraine.

Ditans vs Gepants: A Systematic Review and Indirect Network Meta-Analysis for Comparative Analysis of Efficacy and Safety

Background

An acute attack of migraine, incapacitates the migraineurs, and is widely prevalent. And to warden off its symptoms, recently two groups of drugs have been approved and launched.

Objective

The aim of this systematic review and indirect meta-analysis is to evaluate and summarize the effectiveness of these pharmacological interventions in managing the aforesaid disease.

Material and Methods

An extensive literature search was done through Cochrane library, Pub Med, clincialtrials.gov, for a period of 5 years (2015-2020), using key words: lasmiditan; ubrogepant; rimegepant; and acute migraine. Randomized double-blind phase III clinical trials, published in English language, were included which explored the efficacy and safety of these drugs. The outcomes of this meta-analysis included proportion of patients' headache, most bothersome symptoms free, and no disability at all at 2 h post-dose, with sustained pain freedom 2-24 h, and experiencing any adverse event. An indirect network meta-analysis was also conducted to determine the comparative effectiveness of these drugs.

Results

A total of seven RCTs involving 7266 patients were included. In general, the new drugs demonstrated better result in all the efficacy parameters. The adverse events were observed in treatment group compared to placebo. While in the indirect comparison, lasmiditan emerged to be superior in all the outcomes, except for sustained pain freedom 2-24 h (rimegepant was better). The adverse events were more with lasmiditan.

Conclusion

All the newer drugs have shown significant improvement in the outcomes analyzed. Lasmiditan appears to be superior among the newer drugs in efficacy; however it has more adverse effects.