Unmet Needs in the Acute Treatment of Migraine

Migraine represents the most common neurologic disorder, ranking second among the world's causes of disability [expressed as years lived with disability (YLDs)]. Patients often do not receive the best therapy because of safety issues, tolerance, and prescription accessibility. General practitioners are not always educated about the disease, and specialists are few and often difficult to reach. Therapies are limited and have many side effects that can impede the prescription. Prophylactic therapy is recommended in case of four or more headaches a month, eight or more headache days a month, debilitating headaches, and medication-overuse headaches. The available therapeutic options are in constant development. The classic one consists of non-specific drugs: β-blockers, tricyclics, antiepileptics, and botulinum toxin. Monoclonal antibodies targeting the calcitonin gene receptor (CGRP) peptide or its receptor are the only ones specifically designed to treat migraine. Their efficiency and convenient safety profile have been demonstrated in a number of trials versus both placebo and classic therapies. The treatment of acute migraine attack consists of medications designed to affect the painful symptoms. For over 30 years, the cornerstones of treatment in clinical practice have continued to be represented by triptans and non-steroidal anti-inflammatory drugs (NSAIDs), with the well-know related adverse effects. Opioids are used inappropriately and overprescribed. Polytherapy is strongly not recommended but is still a common practice because treatment is not optimized and thus not efficient. Great promise comes from gepants, also targeting CGRP, and ditans, 5-HT1F receptor agonists. They seem to outweigh the risk of medication overuse headache because of their efficacy and rapid onset and have no cardiovascular contraindications. Nonetheless, these points remain to be confirmed. Although therapies have been implemented in the last years, significant unmet treatment needs remain a reality in patients' lives. This commentary aims to identify the most important unmet needs in the acute treatment of migraine, analyzing the current status of available therapies and their limits. We also analyzed some of the prophylactic therapies available, especially focusing on anti-CGRP monoclonal antibodies, to better understand the importance of setting a therapeutic strategy that includes the two modes, both acute and prophylactic, to reach the best result. We hope that having an overview of the shortcomings will help to provide constructive ideas for improvement.

Unmet Needs in Preventive Treatment of Migraine

Migraine represents the most common cause of work disability in young women and the second one in the general population. Preventive treatment can reduce the frequency of attacks and their intensity, consequently improving the quality of life. Despite this, global health systems have shown important gaps in addressing optimal management of preventive therapy. Despite numerous adverse effects of traditional medications for migraine prevention being well known, these medications continue to be considered the standard of care for prophylaxis of this disease in many contexts. On the other hand, the widespread use of calcitonin gene-related peptide (CGRP) receptor antagonists, which have marked a breakthrough in prophylactic therapy of migraine, has been limited because of their high cost. We also highlight important shortcomings in migraine management by general practitioners (GPs) and poor patient education on the disease with a consequent delay in referring selected patients to dedicated headache centres. Over the next few years, we expect the headache medicine community to mobilize to address these gaps in preventive treatment of migraine.

Atogepant for migraine

Atogepant is a selective oral, small-molecule calcitonin gene-related peptide (CGRP) receptor antagonist that has been approved for preventive treatment of migraine. CGRP is a neuropeptide involved in vasodilation and cerebrovascular regulation. CGRP is the most potent vasoactive constituent of the cerebrovascular trigeminal neuronal system and has a key role in migraine. Medications targeting CGRP are being used as migraine preventive and abortive treatments.

Information on migraine drugs in commonly available Indian drug information sources - Whether we satisfied the community needs?

Drug information can be obtained from various drug information sources that were available as government (National Formulary of India [NFI]; Central Drugs Standard Control Organization [CDSCO]), as well as commercial documents (Current Index of Medical Specialties [CIMS] and Monthly Index of Medical Specialties [MIMS]). Irrational drug usage may happen due to wide variation in the information available in these sources. In this study, we tried to assess these variations in a sample of drugs for the acute-specific management of migraine with ergot and Triptans antimigraine drugs in drug information sources such as NFI, CIMS, MIMS, and CDSCO. Scoring was done for various drug information based on the completeness of information about drugs used in acute-specific management of migraine. The scores for the completeness of drug information about the selected antimigraine drugs are 18.37% for CIMS (Ergotamine, Sumatriptan, Rizatriptan, and Zolmitriptan), 21.1% for NFI (Dihydroergotamine, Sumatriptan), 72.79% for MIMS (Ergotamine tartrate, Sumatriptan, Rizatriptan, Naratriptan, zolmitriptan, Almotriptan) and 21.77% for CDSCO (Ergotamine tartrate, Sumatriptan, Rizatriptan, Naratriptan, Zolmitriptan, eletriptan and almotriptan). The information for the antimigraine drugs available from various sources found to so much deficient. Necessary steps need to be taken in case of government public or hard documents to streamline drug information available with them as well the commercial documents as to provide reliable drug information uniformly for promoting rational use of the drug.

Current Status of Drug Delivery Approaches and Assay of Anti-Migraine Drugs

Migraine is a chronic, painful, neurological disorder that affects approximately 15% of the population worldwide. It is a form of neurovascular headache: a disorder in which neural events result in the dilation of blood vessels that, in turn, results in pain and further nerve activation. The pathogenesis of migraine is not completely understood, but it is thought that both central and peripheral stimulations can play a role in migraine. Experimental pharmacological evidence suggests that some drugs can have actions in migraine treatment and oral drug delivery is the first choice for these drugs. However, the oral absorption of many drugs is delayed during migraine attacks. Therefore, there may be an advantage to other drug delivery routes, such as parenteral and intranasal. Moreover, nanoparticles can be used for improved drug delivery of anti-migraine agents as they can protect the encapsulated drug from biological and/or chemical degradation, and extracellular transport by P-gp efflux proteins. Various analytical studies have been performed to sensitive and selective assays of antimigraine drugs from commercial and real samples. Anti-migraines, either single or combined with other drugs, can be easily detected by several analytical methods, such as ultraviolet spectrometry, visible spectrometry, high-performance liquid chromatography, liquid chromatography-mass spectrometry, and high-performance thin layer chromatography. This review focuses on the status of antimigraine drug delivery technologies and possible routes for drug delivery. Moreover, it will present their analytical assays with different methods.

Rimegepant for the treatment of migraine

Rimegepant is an oral calcitonin gene-related peptide (CGRP) receptor antagonist developed with a novel quick-dissolve oral tablet formulation for the acute treatment of migraine by Biohaven Pharmaceuticals, under license from Bristol Myers Squibb. The completed phase II and III trials showed its efficacy in terms of pain freedom, pain relief, release of migraine symptoms and lifestyle recovery, with an effect sustained up to 48 h. Significant clinical efficacy has been reported with a rimegepant single dose. Rimegepant was well tolerated and the few adverse events were mild or moderate and did not cause trial discontinuation. It received Food and Drug Administration (FDA) approval on February 27, 2020, for the acute treatment of migraine headache. Three clinical trials are currently ongoing to evaluate: i) the long-term safety as migraine acute treatment; ii) the efficacy and safety as a preventive treatment for migraine; and iii) the efficacy and safety for refractory trigeminal neuralgia. Future studies should be designed also to evaluate potential drug-drug interactions.

Ubrogepant to treat migraine

Migraine is the primary headache disorder affecting a significant population worldwide. Ubrogepant is an orally bioavailable calcitonin gene-related peptide (CGRP) receptor antagonist (gepant) approved by the U.S. Food and Drug Administration (FDA) for the acute treatment of migraine headaches with or without aura in adults. Ubrogepant is the first oral CGRP receptor antagonist approved for the acute treatment of migraine. CGRP is an important key mediator of migraine pain; CGRP levels have been shown to be significantly higher during a migraine attack. Two pivotal phase III clinical trials (ACHIEVE I and ACHIEVE II) demonstrated effectiveness and safety of ubrogepant in acute migraine attacks. Ubrogepant can be administered as 50- and 100-mg tablets, with a maximum dose of 200 mg within 48 h. Besides minimizing pain, the drug is equally effective in alleviating migraine-associated symptoms such as nausea, photophobia and sound sensitivity. Unlike other gepants, ubrogepant is free from hepatotoxicity at the therapeutic doses. In certain cases (1 in 5), a full relief of pain was achieved with a single dose of the drug. The molecule is not effective as a preventive migraine therapy. The present review discusses the background, preclinical and clinical pharmacology, indication and safety of ubrogepant for the treatment of migraine attacks.

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.

Antimigraine Drug Avitriptan Is a Ligand and Agonist of Human Aryl Hydrocarbon Receptor That Induces CYP1A1 in Hepatic and Intestinal Cells

The efforts for therapeutic targeting of the aryl hydrocarbon receptor (AhR) have emerged in recent years. We investigated the effects of available antimigraine triptan drugs, having an indole core in their structure, on AhR signaling in human hepatic and intestinal cells. Activation of AhR in reporter gene assays was observed for Avitriptan and to a lesser extent for Donitriptan, while other triptans were very weak or no activators of AhR. Using competitive binding assay and by homology docking, we identified Avitriptan as a low-affinity ligand of AhR. Avitriptan triggered nuclear translocation of AhR and increased binding of AhR in CYP1A1 promotor DNA, as revealed by immune-fluorescence microscopy and chromatin immune-precipitation assay, respectively. Strong induction of CYP1A1 mRNA was achieved by Avitriptan in wild type but not in AhR-knockout, immortalized human hepatocytes, implying that induction of CYP1A1 is AhR-dependent. Increased levels of CYP1A1 mRNA by Avitriptan were observed in human colon carcinoma cells LS180 but not in primary cultures of human hepatocytes. Collectively, we show that Avitriptan is a weak ligand and activator of human AhR, which induces the expression of CYP1A1 in a cell-type specific manner. Our data warrant the potential off-label therapeutic application of Avitriptan as an AhR-agonist drug.

Galcanezumab: a humanized monoclonal antibody for the prevention of migraine and cluster headache

Migraine is a common, painful and highly disabling neurological condition that has plagued mankind for millennia, but its pathophysiology remained largely obscure until recently. The clinical success of triptans for treating migraine and the discovery that calcitonin gene-related peptide (CGRP) plays a prominent role in migraine led to increased research interest into this disease. An important improvement has been the development of monoclonal antibodies, including galcanezumab, that bind to CGRP or to its receptor, preventing its activation. Subsequent clinical trials have reported that galcanezumab is safe and well tolerated, and is effective in reducing the frequency of migraine attacks in patients with episodic or chronic migraine. At the same time, increased study of the pathophysiology of cluster headache, a relatively rare condition with excruciatingly painful headache attacks (i.e., "suicide headaches"), led to the discovery that, as in migraine, CGRP plays an important role in its pathology. Clinical trials suggest that galcanezumab is safe and effective for the prevention of episodic cluster headache, and it is under study for chronic cluster headache. Galcanezumab is approved for the prevention of migraine in the U.S., the European Union, Canada and Mexico, and was also approved for the treatment of episodic cluster headache in the U.S.

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.