Optimising migraine treatment: from drug-drug interactions to personalized medicine

Pharmacogenomic study-A pilot study of the effect of pharmacogenomic phenotypes on the adequate dosing of verapamil for migraine prevention

OBJECTIVE

To investigate factors affecting the efficacy and tolerability of verapamil for migraine prevention using individual pharmacogenomic phenotypes.

BACKGROUND

Verapamil has a wide range of dosing in headache disorders without reliable tools to predict the optimal doses for an individual.

METHODS

This is a retrospective chart review examining adults with existing pharmacogenomic reports at Mayo Clinic who had used verapamil for migraine. Effects of six cytochrome P450 phenotypes on the doses of verapamil for migraine prevention were assessed.

RESULTS

Our final analysis included 33 migraine patients (82% with aura). The mean minimum effective and maximum tolerable doses of verapamil were 178.2(20-320) mg and 227.9(20-480) mg. A variety of CYP2C9, CYP2D6, and CYP3A5 phenotypes were found, without significant association with the verapamil doses after adjusting for age, sex, body mass index, and smoking status.

CONCLUSIONS

We demonstrated a wide range of effective and tolerable verapamil doses used for migraine in a cohort with various pharmacogenomic phenotypes.

Genetics of migraine: complexity, implications, and potential clinical applications

Migraine is a common neurological disorder with large burden in terms of disability for individuals and costs for society. Accurate diagnosis and effective treatments remain priorities. Understanding the genetic factors that contribute to migraine risk and symptom manifestation could improve individual management. Migraine has a strong genetic basis that includes both monogenic and polygenic forms. Some distinct, rare, familial migraine subtypes are caused by pathogenic variants in genes involved in ion transport and neurotransmitter release, suggesting an underlying vulnerability of the excitatory-inhibitory balance in the brain, which might be exacerbated by disruption of homoeostasis and lead to migraine. For more prevalent migraine subtypes, genetic studies have identified many susceptibility loci, implicating genes involved in both neuronal and vascular pathways. Genetic factors can also reveal the nature of relationships between migraine and its associated biomarkers and comorbidities and could potentially be used to identify new therapeutic targets and predict treatment response.

New management strategies for primary headache disorders: Insights from P4 medicine

Primary headache disorder is the main cause of headache attacks, leading to significant disability and impaired quality of life. This disorder is increasingly recognized as a heterogeneous condition with a complex network of genetic, environmental, and lifestyle factors. However, the timely diagnosis and effective treatment of these headaches remain challenging. Precision medicine is a potential strategy based on P4 (predictive, preventive, personalized, and participatory) medicine that may bring new insights for headache care. Recent machine learning advances and widely available molecular biology and imaging data have increased the usefulness of this medical strategy. Precision medicine emphasizes classifying headaches according to their risk factors, clinical presentation, and therapy responsiveness to provide individualized headache management. Furthermore, early preventive strategies, mainly utilizing predictive tools, are critical in reducing headache attacks and improving the quality of life of individuals with headaches. The current review comprehensively discusses the potential application value of P4 medicine in headache management.

Efficacy of tDCS in chronic migraine: A multiprotocol randomized controlled trial

OBJECTIVE

Given the prevalence and complicated pathophysiology of migraine, unknown or varied mechanisms of action of available monotherapies or add-on therapies, and their broad range of adverse effects, it is imperative to manage migraine symptoms using a non-invasive, multifunctional, and alternate monotherapy with no negative impacts.

METHODS

We used a single-blind, randomized, sham-controlled design with baseline, post-test, and 24-weeks follow-up measurements to assess the efficacy of transcranial Direct Current Stimulation (tDCS) in chronic migraine. A total of 150 participants were randomly assigned to the five groups (i.e., allocation ratio of 1:1:1:1:1). Each group received tDCS-intervention for 11 consecutive-weeks (25 sessions; each session = two consecutive montages; each montage = a 20 min duration, 2000 μA intensity).

RESULTS

The multivariate analysis of variance showed significant (p <.05) reductions in chronic migraine symptoms in the four intervention groups. Compared with the sham (η² < 0.18) and other protocols (two = η² > 0.42; three = η² > 0.40; four = η² > 0.51), protocol one [l. anode at the right ventrolateral prefrontal cortices, cathode at the left dorsomedial and superior frontal gyrus-first montage; anode at the right primary motor area, cathode at the medial crosstalk of hemispheres-second montage] showed a larger effect size (η² > 0.59) in the present trial.

CONCLUSIONS

With the applied protocols of the present trial, tDCS can be used as an effective intervention for the prophylactic and therapeutic treatment of chronic migraine. However, while the second protocol was the least effective, the first was the most effective at reducing migraine symptoms.

SIGNIFICANCE

To our knowledge, the present trial is the first study to cover the gaps of the earlier ones, including the parameters like the site of stimulation, electrode range distribution and field intensity, number of sessions, session design, and sample size.

Advances in CGRP Monoclonal Antibodies as Migraine Therapy: A Narrative Review

Migraine is a potentially disabling disorder, yet it remains underdiagnosed and undertreated. The release of the neuropeptide calcitonin gene-related peptide (CGRP) in the trigemino-cerebrovascular system plays a vital role in the evolution of migraine. It enhances peripheral sensitization by mediating neurogenic inflammation and also influences central sensitization. The majority of the drug classes available for migraine prophylaxis are nonspecific and associated with numerous side effects and drug interactions. Anti-CGRP monoclonal antibodies (mAb) are an innovative therapeutic class that fulfills the need for more efficacious and tolerable preventive therapy. While erenumab is a mAb to the CGRP receptor, eptinezumab, fremanezumab, and galcanezumab bind to the CGRP molecule. They decrease the number of headache days and improve disability. Upper respiratory tract infection, nausea, constipation, pain at the site of injection, and fatigue are the associated side effects. CGRP mAbs are an excellent advancement in translational research and are a promising addition in migraine therapy. This article discusses the recent advances in the development of the CGRP mAbs.

Polymorphisms of the Proinflammatory Cytokine Genes Modulate the Response to NSAIDs but Not to Triptans in Migraine Attacks

Migraine is a common neurovascular disorder characterized by recurrent episodes of headache and associated neurological symptoms. At present, a significant portion of patients do not obtain a satisfactory response to acute pain-relieving therapies, including NSAIDs and triptans. In this context, pharmacogenetics plays a key role in the understanding of such a diverse response. In order to investigate whether functional polymorphisms in proinflammatory cytokine genes (IL-1α, IL-1β, IL-1RN; IL-6 and TNF-α) may influence the response to acute treatment, 313 consecutive patients with episodic migraine without aura were enrolled. Pain relief by administration of NSAIDs or triptans for three consecutive migraine attacks was evaluated. We found a significant association between A allele of the TNF-α promoter (−308 A/G) and a lack of efficacy after NSAID administration (p < 0.01, OR 2.51, 95% CI: 1.33 < OR < 4.75 compared to the G allele). Remaining polymorphisms had no significant effect on pain relief. Our study showed that a functional polymorphism in the TNF-α gene significantly modulates the clinical response to NSAID administration in acute attacks. Patients with higher production of the active cytokine during stress showed a significantly lower anti-migraine effect. Our results further support a role for TNF-α in the pathophysiological mechanisms of migraine attack.

Reaching the Nadir of Medication Overuse in Chronic Migraine

The introduction of new drug classes for chronic migraine, such as monoclonal antibodies for calcitonin-gene-related peptide or its receptor (CGRPr), or antagonists of the same CGRP, have opened a new scenario in a selected population of individuals with migraine, and those presenting with chronic form of migraine in association with medication overuse. Medication overuse is now considered a complication of chronic migraine and, in fact, the treatment with CGRP(r)-MAbs of chronic migraine with medication overuse results in a clinical improvement of chronic migraine itself, accompanied by a parallel and obvious reduction in the intake of specific and non-specific acute migraine drugs. Education on the correct use of these drugs will be an essential tool to reduce the disability and costs of people suffering from CM complicated by MO, considering the long-term safety of the new therapies targeting the CGRP pathways. Only in this way can medication overuse risk can be reduced at its nadir in the scenario of chronicity of migraines.

Prescription Advice Based on Data of Drug-Drug-Gene Interaction of Patients with Polypharmacy

Purpose

Pharmacogenetic counselling is a complex task and requires the efforts of an interdisciplinary team, which cannot be implemented in most cases. Therefore, simple rules could help to minimize the risk of medications incompatible with each other or with frequent genetic variants.

Patients and Methods

One hundred and eighty-four multi-morbid Caucasian patients suffering from side effects or inefficient therapy were enrolled and genotyped. Their medication was analyzed by a team of specialists using Drug-PIN^® (medication support system) and individual recommendations for 34 drug classes were generated.

Results

In each of the critical drug classes, 50% of the drugs cannot be recommended to be prescribed in typical drug cocktails. PPIs and SSRI/SNRIs represent the most critical drug classes without showing a single favorable drug. Among the well-tolerated drugs (not recommended for less than 5% of the patients) are metamizole, celecoxib, olmesartan and famotidine. For each drug class, a ranking of active ingredients according to their suitability is presented.

Conclusion

Genotyping and its profound analysis are not available in many settings today. The consideration of frequent alterations of metabolic elimination routes and drug–drug–gene interactions by using simple rankings can help to avoid many incompatibilities, side effects and inefficient therapies.

Drug Safety in Episodic Migraine Management in Adults Part 1: Acute Treatments

PURPOSE OF REVIEW

The aim of this review is to aid in choosing safe options when assessing potential risks of acute migraine treatments based on known mechanisms of action and anticipated safety concerns.

RECENT FINDINGS

Part 1 highlights safety issues associated with commonly used medications to treat acute migraine attacks. Strategies to mitigate cardiovascular and gastrointestinal risks of nonsteroidal anti-inflammatory drugs, evaluation of cardiovascular risks of triptan and ergot alkaloids, and precautions with use of antiemetics and the novel drugs gepants and ditans are discussed to help practitioners in clinical decision-making. When available, we included recommendations from professional societies and data from pharmacovigilance systems. While guidelines on efficacy are available, one must also consider the possible risks and adverse effects of a drug when creating treatment plans.

CURRENT PERSPECTIVES ON MITOCHONDRIAL DYSFUNCTION IN MIGRAINE

Mitochondria is an autonomous organelle that plays a crucial role in the metabolic aspects of a cell. Cortical Spreading Depression (CSD) and fluctuations in the cerebral blood flow have for long been mechanisms underlying migraine. It is a neurovascular disorder with a unilateral manifestation of disturbing, throbbing and pulsating head pain. Migraine affects 2.6 and 21.7% of the general population and is the major cause of partial disability in the age group 15-49. Higher mutation rates, imbalance in concentration of physiologically relevant molecules, oxidative stress biomarkers have been the main themes of discussion in determining the role of mitochondrial disability in migraine. The correlation of migraine with other disorders like hemiplegic migraine, MELAS, TTH, CVS, ischemic stroke and hypertension has helped in the assessment of the physiological and morphogenetic basis of migraine. Here, we have reviewed the different nuances of mitochondrial dysfunction and migraine. The different mtDNA polymorphisms that can affect the generation and transmission of nerve impulse has been highlighted and supported with research findings. In addition to this, the genetic basis of migraine pathogenesis as a consequence of mutations in nuclear DNA that can in turn affect the synthesis of defective mitochondrial proteins is discussed along with a brief overview of epigenetic profile. This review gives an overview of the pathophysiology of migraine and explores mitochondrial dysfunction as a potential underlying mechanism. Also, therapeutic supplements for managing migraine have been discussed at different junctures in this paper.

P-Glycoprotein and Breast Cancer Resistance Protein Transporter Inhibition by Cyclosporine and Quinidine on the Pharmacokinetics of Oral Rimegepant in Healthy Subjects

Rimegepant (Nurtec ODT)—an orally administered, small‐molecule calcitonin gene–related peptide receptor antagonist indicated for the acute and preventive treatment of migraine—is a substrate for both the P‐glycoprotein and breast cancer resistance protein transporters in vitro. We evaluated the effects of concomitant administration of strong inhibitors of these transporters on the pharmacokinetics of rimegepant in healthy subjects. This single‐center, open‐label, randomized study was conducted in 2 parts, both of which were 2‐period, 2‐sequence, crossover studies. Part 1 (n = 15) evaluated the effect of a single oral dose of 200‐mg cyclosporine, a strong inhibitor of the P‐glycoprotein and breast cancer resistance protein transporters, on the pharmacokinetics of rimegepant 75 mg. Part 2 (n = 12) evaluated the effect of a single oral dose of 600‐mg quinidine, a strong selective P‐glycoprotein transporter, on the pharmacokinetics of rimegepant 75 mg. Coadministration with cyclosporine showed an increase in rimegepant area under the plasma concentration–time curve from time 0 to infinity and maximum observed concentration based on geometric mean ratios (90% confidence intervals [CIs]) of 1.6 (1.49‐1.72) and 1.41 (1.27‐1.57), respectively, versus rimegepant alone. Coadministration with quinidine showed an increase in rimegepant area under the plasma concentration–time curve from time 0 to infinity and maximum observed concentration geometric mean ratios (90% CIs) of 1.55 (1.40‐1.72) and 1.67 (1.46‐1.91), respectively, versus rimegepant alone. Strong P‐glycoprotein inhibitors (cyclosporine, quinidine) increased rimegepant exposures (>50%, <2‐fold). In parts 1 and 2, rimegepant coadministration was well tolerated and safe. The similar effect of cyclosporine and quinidine coadministration on rimegepant exposure suggests that inhibition of breast cancer resistance protein inhibition may have less influence on rimegepant exposure.

Pharmacogenetics in Primary Headache Disorders

Primary headache disorders, such as migraine, tension-type headache (TTH), and cluster headache, belong to the most common neurological disorders affecting a high percentage of people worldwide. Headache induces a high burden for the affected individuals on the personal level, with a strong impact on life quality, daily life management, and causes immense costs for the healthcare systems. Although a relatively broad spectrum of different pharmacological classes for the treatment of headache disorders are available, treatment effectiveness is often limited by high variances in therapy responses. Genetic variants can influence the individual treatment success by influencing pharmacokinetics or pharmacodynamics of the therapeutic as investigated in the research field of pharmacogenetics. This review summarizes the current knowledge on important primary headache disorders, including migraine, TTH, and cluster headache. We also summarize current acute and preventive treatment options for the three headache disorders based on drug classes and compounds taking important therapy guidelines into consideration. Importantly, the work summarizes and discusses the role of genetic polymorphisms regarding their impact on metabolism safety and the effect of therapeutics that are used to treat migraine, cluster headache, and TTH exploring drug classes such as nonsteroidal anti-inflammatory drugs, triptans, antidepressants, anticonvulsants, calcium channel blockers, drugs with effect on the renin-angiotensin system, and novel headache therapeutics such as ditans, anti-calcitonin-gene-related peptide antibodies, and gepants. Genetic variants in important phase I-, II-, and III-associated genes such as cytochrome P450 genes, UGT genes, and different transporter genes are scrutinized as well as variants in genes important for pharmacodynamics and several functions outside the pharmacokinetic and pharmacodynamic spectrum. Finally, the article evaluates the potential and limitations of pharmacogenetic approaches for individual therapy adjustments in headache disorders.

Ubrogepant Is Safe and Efficacious in Participants Taking Concomitant Preventive Medication for Migraine: A Pooled Analysis of Phase 3 Trials

INTRODUCTION

Ubrogepant is a calcitonin gene-related peptide receptor antagonist indicated for acute treatment of migraine that can be used to treat breakthrough attacks in individuals taking preventive treatment for migraine. We evaluated the impact of preventive medication use on the efficacy and safety of ubrogepant for the acute treatment of migraine.

METHODS

This was an analysis of pooled efficacy data from the ACHIEVE I and ACHIEVE II phase 3 trials, in which efficacy of ubrogepant was assessed at 2 h after taking study medication for pain freedom, absence of most bothersome symptom (MBS), and pain relief. In addition, a long-term safety (LTS) extension trial was completed where safety was assessed on the basis of incidence and severity of treatment-emergent adverse events (TEAEs). Outcomes were compared between participants with or without prior (within 6 months) preventive medication use (anticonvulsants, beta blockers, antidepressants, or onabotulinumtoxinA). For efficacy analyses, data were pooled across ACHIEVE trials for the 50 mg and placebo groups; for safety analyses, data for all dose groups (50 mg and 100 mg) in the LTS trial were pooled.

RESULTS

Preventive treatments were used by 417 of 2247 (18.6%) participants analyzed in the ACHIEVE trials and by 143 of 813 (17.5%) participants in the LTS trial. Responder rates for all outcomes were similar between participants with or without preventive treatment within each dose group (p > 0.05). No significant differences were noted across the different preventive medications. Rates and types of TEAEs were similar between participants with or without preventive treatment. No serious treatment-related adverse events were reported.

CONCLUSION

Efficacy and safety of ubrogepant for the acute treatment of migraine were similar between participants with or without prior or current use of concomitant preventive medication.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers: NCT02828020 (ACHIEVE I), NCT02867709 (ACHIEVE II), and NCT02873221 (long-term safety trial).

Newer Horizon for Treatment of Acute Attack of Migraine: Lasmiditan and Ubrogepant

Migraine is characterized by severe, intermittent headache attacks with associated symptoms including nausea, vomiting, phonophobia, and photophobia. Still Triptans (selective 5-HT_1B/D agonists) are considered as the first-line therapy in acute attack of migraine. Recently two new drugs Lasmiditan and Ubrogepant were approved by United States Food and Drug Administration in acute attack of migraine with or without aura in adults. Lasmiditan is a highly selective 5-HT_1F receptor agonist which demonstrated superiority to placebo in the acute treatment of migraine in adults with moderate/severe migraine disability in two similarly designed phase-3 trials, SAMURAI and SPARTAN. Ubrogepant is a novel small molecule oral calcitonin gene-related peptide receptor antagonist. The approval was supported by two pivotal phase-3, randomized, double-blind, placebo-controlled trials (ACHIEVE I and ACHIEVE II) that evaluated the efficacy, safety, tolerability. Hopefully, these two drugs may soon be a new addition to the mounting armory of drugs against migraine and may fulfill a substantial unmet need.

A review of migraine genetics: gathering genomic and transcriptomic factors

Migraine is a common and complex neurologic disorder that affects approximately 15-18% of the general population. Although the cause of migraine is unknown, some genetic studies have focused on unravelling rare and common variants underlying the pathophysiological mechanisms of this disorder. This review covers the advances in the last decade on migraine genetics, throughout the history of genetic methodologies used, including recent application of next-generation sequencing techniques. A thorough review of the literature interweaves the genomic and transcriptomic factors that will allow a better understanding of the mechanisms underlying migraine pathophysiology, concluding with the clinical utility landscape of genetic information and future consideration to creating a new frontier toward advancing the field of personalized medicine.

Individualized Drugs' Selection by Evaluation of Drug Properties, Pharmacogenomics and Clinical Parameters: Performance of a Bioinformatic Tool Compared to a Clinically Established Counselling Process

Purpose

Inefficacy and safety concerns are main medications’ problems, especially in the case of poly-therapies, when drug–drug interactions may alter the expected drug disposition. Ongoing efforts are aimed to establish drug selection processes aimed to preemptive evaluation of a plethora of factors affecting patient’s specific drug response, including pharmacogenomic markers, in order to minimize prescription of improper medications. In previous years, we established at the University Hospital Sant’Andrea of Rome, Italy, a Precision Medicine Service based on a multi-disciplinary experts’ team. The team is in charge to produce a drug therapy counselling report, including pharmacogenomic, pharmacokinetic and pharmacodynamic considerations. In this study, we aimed to evaluate the performance of this established “manual” process of therapy selection with a novel bioinformatic tool, the Drug-PIN system.

Patients and Methods

A total of 200 patients diagnosed with Major Depressive Disorders or a depressive episode in Bipolar Disorder, with at least three previous failed treatments, who underwent pharmacogenomic profiling and therapy counselling in the Sant’Andrea Hospital from 2017 to 2020. The baseline poly-therapy of these patients was re-evaluated and optimized by Drug-PIN. Results of the Drug-PIN poly-therapy evaluation/optimization were compared with the results of the original poly-therapy evaluation/optimization by therapy counselling. To compare the results between the two processes, the risk associated with each poly-therapy was classified as low, moderate, or high.

Results

The number of baseline poly-therapies classified in low-, moderate- or high-risk did not change significantly between manual system or Drug-PIN system. As the counselling process, also the Drug-PIN system produces a significant decrease in the predicted treatment-associated risk.

Conclusion

Drug-PIN substantially replicates the output of the counselling process, allowing a substantial reduction in the time needed for therapy evaluation. Availability of an effective bioinformatic tool for proper drug selection is expected to exponentially increase the actuation of targeted therapy strategies.

Role of CGRP pathway polymorphisms in migraine: a systematic review and impact on CGRP mAbs migraine therapy

Background

the interest of clinical reaseach in polymorphisms and epigenetics in migraine has been growing over the years. Due to the new era of preventative migraine treatment opened by monoclonal antibodies (mAbs) targeting the signaling of the calcitonin-gene related peptide (CGRP), the present systematic review aims at identifying genetic variants occurring along the CGRP pathway and at verifying whether these can affect the clinical features and the course of disease and the responsiveness of patients to therapy.

Methods

the literature search has been conducted consulting the most relevant scientific databases, i.e. PubMed/MEDLINE, Scopus, Web of Science, the Human Genome Epidemiology (HuGE) Published Literature database (Public Health Genomics Knowledge Base) and Clinicaltrials.gov from database inception until April 1, 2021. The process of identification and selection of the studies included in the analysis has followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) criteria for systematic reviews and meta-analyses and the guidance from the Human Genome Epidemiology Network for reporting gene-disease associations.

Results

the search has retrieved 800 results, among which only 7 studies have met the eligibility criteria for inclusion in the analysis. The latter are case-control studies of genetic association and an exploratory analysis and two polymorphisms have been detected as the most recurring: the rs3781719 (T > C) of the CALC A gene encoding CGRP and the rs7590387 of the gene encoding the receptor activity-modifying protein (RAMP) 1 (C > G). Only one study assessing the methylation pattern with regard to CGRP pathway has been found from the search. No genetic association studies investigating the possible effect of genetic variants affecting CGRP signaling on the responsiveness to the most recent pharmacological approaches, i.e. anti-CGRP(R) mAbs, gepants and ditans, have been published. According to the Human Genome Epidemiology (HuGE) systematic reviews and meta-analyses risk-of-bias score for genetic association studies, the heterogeneity between and across studies and the small sample size do not allow to draw conclusions and prompt future studies.

Conclusions

adequately powered, good quality genetic association studies are needed to understand the impact of genetic variants affecting the pathway of CGRP on migraine susceptibility and clinical manifestation and to predict the response to therapy in terms of efficacy and safety.

Safety and tolerability of preventive treatment options for chronic migraine

INTRODUCTION

Relative to migraine generally, chronic migraine (CM) imposes greater disability, healthcare utilization and socioeconomic burden. Six therapies currently possess a credible evidence base for prevention/suppression of CM. This review is intended to provide an assessment of their relative utility, defined as a blend of safety, tolerability and efficacy, focusing in particular on their safety and tolerability.Areas Covered: We discuss all six medications currently FDA-approved for migraine prevention which also specifically possess credible evidence of efficacy in treating CM. While we do address the efficacy of each, our primary emphasis involves assessment of safety and tolerability data derived from clinical trials and post-marketing experience.Expert Opinion: Recent research involving CM has led to the identification of highly targeted and typically well-tolerated therapies. For patients who experience obstacles to accessing these newer therapies, topiramate is available as an evidence-based alternative, but contraindications, drug-drug interactions and poor tolerability may limit or prevent its use. Although data to support such intervention presently is limited, clinically challenging CM cases may benefit from combination therapy. 'Real world' studies are needed to evaluate such polytherapy, along with studies intended to assess the long-term safety of the individual therapies and their use during pregnancy and breast-feeding.

CGRP Receptor Antagonists and 5-HT1F Receptor Agonist in the Treatment of Migraine

Discovering that calcitonin-related peptide (CGRP) plays a key role in the complex pathophysiology of migraine has allowed us to make great strides in the development of new approaches for acute and preventive treatment. This evidence has led to the development of small molecules antagonist molecules of the CGRP receptor ("gepants") and of a new class of medications called "Ditans". This review presents the data from clinical trials reporting the efficacy, safety, and tolerability of the new drugs used in the treatment of migraines. Evidences show that therapeutic approaches targeted to CGRP have the potential to transform the clinical management of migraine, even though its appropriate place has yet to be determined with accuracy.

Early Management of OnabotulinumtoxinA Treatment in Chronic Migraine: Insights from a Real-Life European Multicenter Study

Introduction

OnabotulinumtoxinA (BT-A) quarterly was the first treatment approved specifically for chronic migraine (CM). It is unclear whether three cycles are better than two to assess early BT-A response.

Methods

We performed a retrospective analysis on real-life prospectively collected data in 16 European headache centers. All the centers provided data on patients treated with BT-A for CM over the first three cycles of treatment. For each treatment cycle we defined patients as “good responders” if reporting a ≥ 50% reduction in monthly headache days compared with the three months before starting BT-A, “partial responders” if reporting a 30–49% reduction in monthly headache days, and “non-responders” if reporting a < 30% reduction in monthly headache days or stopping the treatment before the third cycle.

Results

We included 2879 patients. Seven hundred and eighty-four (64.6%) of the 1213 patients reporting a good response during the first and/or the second cycle had a good response during the third cycle; 309 (49.3%) of the 627 patients reporting a partial response (but no good response) during the first and/or the second cycle had a good response during the third cycle; only 65 (6.3%) of the 1039 patients who did not respond during both the first two cycles achieved a good response during the third cycle. Multivariate analyses showed that partial or good response during the first or the second cycle were independently associated with good response during the third cycle.

Conclusions

Our data suggest that patients with CM responding to BT-A during the first two cycles will likely benefit from the third cycle of treatment, while the probability that non-responders to the first two cycles start responding during the third cycle is low. These results can help guide the individual decision to stop or continue treatment after the second cycle in patients who have not responded to the first two cycles.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00253-0.

Non-interacting, Non-opioid, and Non-barbiturate Containing Acute Medication Combinations in Headache: A Pilot Combinatorics Approach Based on DrugBank Database

Background: Polypharmacy in abortive medications is often inevitable for patients with refractory headaches.

Objective: We seek to enumerate an exhaustive list of headaches abortive medications that are without drug-drug interactions.

Methods: We updated a list of acute medications based on the widely used Jefferson Headache Manual with novel abortive medications including ubrogepant, lasmiditan, and rimegepant. Opioids and barbiturate-containing products are excluded. From this resultant list of medications, we then conducted an exhaustive search of all pair-wise interactions via DrugBank's API. Using this interaction list, we filtered all possible two, three, and four drug combinations of abortive medications. The list of medications was then reapplied to DrugBank to verify the lack of known drug-drug interactions.

Results: There are 192 medication combinations that do not contain any drug-drug interactions. Most common elements in these combinations are ubrogepant, prochlorperazine, followed by tizanidine. There are 67 three-drug combinations that do not contain interactions. Only two of the four-drug combinations do not yield some form of drug-drug interactions.

Conclusion: This list of headaches abortive medications without drug-drug interactions is a useful tool for clinicians seeking to more effectively manage refractory headaches by implementing a rational polypharmacy.

Supersaturation of VEP in Migraine without Aura Patients Treated with Topiramate: An Anatomo-Functional Biomarker of the Disease

Migraine is a primary headache with high prevalence among the general population, characterized by functional hypersensitivity to both exogenous and endogenous stimuli particularly affecting the nociceptive system. The hyperresponsivity of cortical neurons could be due to a disequilibrium in the excitatory/inhibitory signaling. This study aimed to investigate the anatomo-functional pathway from the retina to the primary visual cortex using visual evoked potentials (VEP). Contrast gain protocol was used in 15 patients diagnosed with migraine without aura (at baseline and after 3 months of topiramate therapy) and 13 controls. A saturation (S) index was assessed to monitor the response of VEP’s amplitude to contrast gain. Non-linear nor monotone growth of VEP (S < 0.95) was defined as supersaturation. A greater percentage of migraine patients (53%) relative to controls (7%) showed this characteristic. A strong inverse correlation was found between the S index and the number of days separating the registration of VEP from the next migraine attack. Moreover, allodynia measured through the Allodynia Symptoms Check-list (ASC-12) correlates with the S index both at baseline and after 3 months of topiramate treatment. Other clinical characteristics were not related to supersaturation. Topiramate therapy, although effective, did not influence electrophysiological parameters suggesting a non-intracortical nor retinal origin of the supersaturation (with possible involvement of relay cells from the lateral geniculate nucleus). In conclusion, the elaboration of visual stimuli and visual cortex activity is different in migraine patients compared to controls. More data are necessary to confirm the potential use of the S index as a biomarker for the migraine cycle (association with the pain-phase) and cortical sensitization (allodynia).

Pharmacokinetics, Pharmacodynamics and Drug-Drug Interactions of New Anti-Migraine Drugs-Lasmiditan, Gepants, and Calcitonin-Gene-Related Peptide (CGRP) Receptor Monoclonal Antibodies

In the last few years, there have been significant advances in migraine management and prevention. Lasmiditan, ubrogepant, rimegepant and monoclonal antibodies (erenumab, fremanezumab, galcanezumab, and eptinezumab) are new drugs that were launched on the US pharmaceutical market; some of them also in Europe. This publication reviews the available worldwide references on the safety of these anti-migraine drugs with a focus on the possible drug–drug (DDI) or drug–food interactions. As is known, bioavailability of a drug and, hence, its pharmacological efficacy depend on its pharmacokinetics and pharmacodynamics, which may be altered by drug interactions. This paper discusses the interactions of gepants and lasmiditan with, i.a., serotonergic drugs, CYP3A4 inhibitors, and inducers or breast cancer resistant protein (BCRP) and P-glycoprotein (P-gp) inhibitors. In the case of monoclonal antibodies, the issue of pharmacodynamic interactions related to the modulation of the immune system functions was addressed. It also focuses on the effect of monoclonal antibodies on expression of class Fc gamma receptors (FcγR).

Migraine and Ischemic Stroke: Deciphering the Bidirectional Pathway

Migraine and stroke are common, disabling neurological conditions with several theories being proposed to explain this bidirectional relationship. Migraine is considered as a benign neurological disorder, but research has revealed a connection between migraine and stroke, predominantly those having migraine with aura (MA). Among migraineurs, females with MA are more susceptible to ischemic stroke and may have a migrainous infarction. Migrainous infarction mostly occurs in the posterior circulation of young women. Although there are several theories about the potential relationship between MA and stroke, the precise pathological process of migrainous infarction is not clear. It is assumed that cortical spreading depression (CSD) might be one of the essential factors for migrainous infarction. Other factors that may contribute to migrainous infarction may be genetic, hormonal fluctuation, hypercoagulation, and right to left cardiac shunts. Antimigraine drugs, such as ergot alkaloids and triptans, are widely used in migraine care. Still, they have been found to cause severe vasoconstriction, which may result in the development of ischemia. It is reported that patients with stroke develop migraines during the recovery phase. Both experimental and clinical data suggest that cerebral microembolism can act as a potential trigger for MA. Further studies are warranted for the treatment of migraine, which may lead to a decline in migraine-related stroke. In this present article, we have outlined various potential pathways that link migraine and stroke.

Targeting CGRP for migraine treatment: mechanisms, antibodies, small molecules, perspectives

INTRODUCTION

Calcitonin Gene-Related Peptide (CGRP) has gradually emerged as a suitable therapeutic target to treat migraine. Considering the social and economic burden of migraine, it is fundamental to optimize the disease management with efficacious and safe treatments. In this scenario, drugs targeting GCRP, monoclonal antibodies (MoAbs) and gepants, represent new therapeutic strategies.

AREAS COVERED

In the present work, the authors aim at appraising the main insights and implications of treatments targeting CGRP by reviewing pathophysiology and clinical information.

EXPERT OPINION

Anti-CGRP MoAbs are the first migraine-specific preventive treatments representing a suitable option especially for difficult-to-treat patients. They can be safely administered for long periods even in association with preventatives acting on different targets. Gepants are a safe alternative to triptans for the acute management of migraine and are currently being tested for prevention, thus representing the first transitional molecules for disease therapy. In the future, it might be possible to adapt the treatment according to patients' characteristics and disease phenotype even combining the two treatments targeting the CGRP pathway.

Headache medication and the COVID-19 pandemic

The world is currently dominated by the Corona Virus Disease 2019 (COVID-19) pandemic. Besides the obvious concerns about limitation of virus spread and providing the best possible care to infected patients, a concomitant concern has now arisen in view of a putative link between the use of certain drugs, such as Renin-Angiotensin System (RAS) inhibitors and ibuprofen, and an increased risk for COVID-19 infection. We here discuss this concern in relation to headache treatment and conclude that, based on current evidence, there is no reason to abandon treatment of headache patients with RAS inhibitors or ibuprofen.

Persistent Post-Traumatic Headache and Migraine: Pre-Clinical Comparisons

Background: Oftentimes, persistent post traumatic headache (PPTH) and migraine are phenotypically similar and the only clinical feature that differentiate them is the presence of a mild or moderate traumatic brain injury (mTBI). The aim of this study is to describe the differences in brain area and in biochemical cascade after concussion and to define the efficacy and safety of treatments in use. Methods: Sources were chosen in according to the International Classification of Headache Disorder (ICHD) criteria. Results: The articles demonstrated a significant difference between PPTH and migraine regarding static functional connectivity (sFC) and dynamic functional connectivity (dFC) in brain structure that could be used for exploring the pathophysiological mechanisms in PPTH. Many studies described a cascade of neuro-metabolic changes that occur after traumatic brain injury. These variations are associated to the mechanism occurring when developing a PPTH. Conclusions: The state of art of this important topic show how although the mechanisms underlying the development of the two different diseases are different, the treatment of common migraine is efficacious in patients that have developed a post traumatic form.

CGRP Inhibitors for Migraine

Migraine headaches remain a significant medical concern; lots of people are adversely affected. Many existing pharmacotherapies have disappointing results. The pathophysiology is related to calcitonin gene-related peptide (CGRP) pathways. There is hope for better efficacy from the now-available CGRP inhibitor drugs made available to patients suffering these cephalgias.

Profiling lasmiditan as a treatment option for migraine

Introduction: In recent years, research into acute migraine treatment has aimed to develop molecules capable of inhibiting trigeminal pathways, mediated by agonism to 5-HT1F receptors in order to avoid the vasoconstrictive action due to the stimulation of 5-HT 1B/1D receptors. A novel migraine drug class, called 'neurally acting anti-migraine agents', has been developed for the management of acute migraine attacks. Lasmiditan is the only compound of this drug class that has been evaluated in Phase III clinical trials.Areas covered: This review discusses lasmiditan including its pharmacokinetics, pharmacodynamics, efficacy and safety profile. Original research and review articles, relative to the period 2010-2019, were included in the reviewed literature.Expert opinion: The most recent phase III trials have demonstrated the efficacy of lasmiditan for acute migraine treatment, even if compared only with placebo. Nevertheless, the low rate of cardiovascular side effects with lasmiditan might offer a potential therapeutic option for migraine patients with cardiovascular disorders. With the lack of data on lasmiditan's pharmacokinetic features, several phase I clinical trials are still ongoing in order to evaluate half-life, metabolism, excretion and the potential production of active metabolites. Possible pharmacodynamic interaction with drugs acting on central nervous system should be evaluated in future studies.

A Phase I, Randomized, Single‑Blind, Placebo‑Controlled, Single Ascending Dose Study of the Safety, Tolerability, and Pharmacokinetics of Subcutaneous and Oral TRV250, a G Protein-Selective Delta Receptor Agonist, in Healthy Subjects

BACKGROUND

The delta opioid receptor (DOR) has been identified as a therapeutic target for migraine, with DOR agonists exhibiting low abuse potential compared with conventional µ-opioid agonists. TRV250 is a novel small molecule agonist of the DOR that is preferentially selective for G-protein signaling, with relatively little activation of the β-arrestin2 post-receptor signaling pathway. This selectivity provides reduced susceptibility to proconvulsant activity seen with non-selective DOR agonists. TRV250 significantly reduced nitroglycerin-evoked hyperalgesia in rodents, indicating a potential utility in acute migraine without the risk of seizure activity or abuse potential.

OBJECTIVE

This trial evaluated the safety, tolerability, and pharmacokinetics of ascending dose levels of TRV250 administered subcutaneously (SC) and the relative bioavailability of TRV250 administered orally compared with SC administration.

METHODS

This was a two-part, single ascending dose study. Part A included four cohorts of healthy adults (N = 38). Each cohort was dosed on three occasions (placebo and two different dose levels of TRV250, allocated in randomized order and administered by SC route). In Part B, a single cohort of nine subjects received an oral dose of either TRV250 (n = 7) or placebo (n = 2) in a fed or fasted state. Serial blood samples were obtained for pharmacokinetic determination across a 24-h post-dose period. Safety assessments included clinical laboratory measures, vital signs, 12-lead electrocardiogram (ECG), and electroencephalogram (EEG) pre- and post-dosing.

RESULTS

TRV250 was well tolerated. There were no serious adverse events (SAEs), and all AEs were mild in severity. Injection-site reactions and headache were the most common AEs. One subject was withdrawn from the study due to a TRV250-related AE of postural orthostatic tachycardia. There were no clinically relevant changes in physical examination, hematology, clinical chemistry, urinalysis, suicidal ideation, or vital signs, with the exception of orthostatic changes in some subjects. No subject experienced abnormalities in EEGs or experienced a change from baseline in heart-rate-corrected QT interval (QTcF) > 60 ms, or an absolute QTcF interval > 480 ms at any post-dosing observation. Peak and total plasma exposure to TRV250 increased in a dose-proportional manner following 0.1-30 mg SC doses, with the mean half-life ranging from 2.39 to 3.76 h. Oral bioavailability of TRV250 ranged from 14% (fasting) to 19% (fed) relative to SC dosing, while administration with food increased the AUC but decreased the rate of absorption as reflected by a modest delay in median time to maximum concentration and a slight reduction in maximum concentration.

CONCLUSION

The findings from the first-in-human study support further evaluation of TRV250, a G-protein selective DOR agonist, in the treatment of acute migraine.

The future of pharmacogenetics in the treatment of migraine

Migraine is considered one of the most disabling neurological disorder with a high socioeconomic burden. Pharmacological management includes many classes of drugs which in the most cases, are administrated in polytherapy. The therapeutic scheme of migraineurs is often affected by comorbidities which need concomitant medications, thus increasing the risk of side effects related to drug-drug interactions. Pharmacogenetics is a promising tool to achieve a personalized cure based on individual genetic profile while the availability of free online knowledge bases allows to check the potential DDIs of selected medications. Combining, these approaches may offer to clinicians a useful tool to improve the appropriateness of migraine polytherapy choice, aiming to increase the efficacy and reduce the toxicity of pharmacological treatments.

A Prospective Observational Cohort Study on Pharmacological Habitus, Headache-Related Disability and Psychological Profile in Patients with Chronic Migraine Undergoing OnabotulinumtoxinA Prophylactic Treatment

Chronic Migraine (CM) is a disabling neurologic condition with a severe impact on functioning and quality of life. Successful therapeutic management of patients with CM is complex, and differences in therapeutic response could be attributable to genetically determined factors, sensitivity to pharmacological treatment, psychosocial and relational factors affecting the patient’s compliance and approach on the therapeutic treatment. The aim of this prospective observational study was to explore self-efficacy, coping strategies, psychological distress and headache-related disability in a cohort of 40 patients with CM (mean age: 46.73; standard deviation 13.75) treated with OnabotulinumtoxinA and the relationship between these clinical and psychological aspects and acute medication consumption during OnabotulinumtoxinA prophylactic treatment. Patients presented an overall significant reduction in the Headache Index (HI) (p < 0.001), HI with severe intensity (p = 0.009), and total analgesic consumption (p = 0.003) after the prophylactic treatment. These results are in line with the literature. Despite this, higher nonsteroidal anti-inflammatory drugs consumption was associated with higher psychological distress, higher HI with severe and moderate intensity, and worse quality of life. Conversely, triptans consumption was correlated with HI of mild intensity, and problem-focused coping strategies. To conclude, the psychological profile, and in particular, the psychological distress and specific coping strategies might influence the self-management of acute medication.