Triptans in migraine: a comparative review of pharmacology, pharmacokinetics and efficacy

Substituent-Dependent, Switchable Synthesis of Nonaromatic and Aromatic Heterocyclic Sulfones Using Visible Light

In this Letter, we described a visible-light-induced switchable synthesis of nonaromatic and aromatic sulfonyl heterocycles. The product selectivity between 2,5-dihydropyrrole and pyrrole can be tuned by altering the substituent on the N atom of 1,6-diyne. We highlight the intricacy and efficiency of this approach in constructing molecular frameworks under mild conditions with a high functional group tolerance. This study elucidates the mechanism underlying product selectivity, highlighting its potential as a compelling alternative to traditional synthetic techniques.

Sustainable C-H Methylation Employing Dimethyl Carbonate

The use of CO2 and CO2-derived chemicals offers society sustainable and biocompatible chemistry for a variety of applications, ranging from materials to medicines. In this context, dimethyl carbonate (DMC) stands out owing to its low toxicity, high biodegradability, tunable reactivity, and sustainable production. Further, the ability of DMC to act as an ambient electrophile at varied temperatures and reaction conditions in order to produce methoxycarbonylated (via BAC2) and methylated products (via BAL2) is very promising. While the methylation of hetero-H (N-, O-, and S-methylation) with DMC is established and well-reviewed, the C-H methylation reaction with DMC is limited, and there is no specific literature detailing the C-methylation reaction using DMC, creating new opportunities as well as challenges in the same domain. In this context, the present perspective focuses on the new breakthroughs, recent advances, and trends in C-H methylation reactions employing DMC. A critical analysis of the mechanistic course of reactions under each category was undertaken. We believe this timely perspective will offer an in-depth analysis of existing literature with critical remarks, which will certainly inspire fellow researchers across disciplines to understand and pursue cutting-edge research in the area of C-H methylation (alkylation) using DMC and related organic carbonates.

Engineering the L-tryptophan metabolism for efficient de novo biosynthesis of tryptophol in Saccharomyces cerevisiae

Tryptophol (IET) is a metabolite derived from L-tryptophan that can be isolated from plants, bacteria, and fungi and has a wide range of biological activities in living systems. Despite the fact that IET biosynthesis pathways exist naturally in living organisms, industrial-scale production of IET and its derivatives is solely based on environmentally unfriendly chemical conversion. With diminishing petroleum reserves and a significant increase in global demand in all major commercial segments, it becomes essential to develop new technologies to produce chemicals from renewable resources and under mild conditions, such as microbial fermentation. Here we characterized and engineered the less-studied L-tryptophan pathway and IET biosynthesis in the baker's yeast Saccharomyces cerevisiae, with the goal of investigating microbial fermentation as an alternative/green strategy to produce IET. In detail, we divided the aromatic amino acids (AAAs) metabolism related to IET synthesis into the shikimate pathway, the L-tryptophan pathway, the competing L-tyrosine/L-phenylalanine pathways, and the Ehrlich pathway based on a modular engineering concept. Through stepwise engineering of these modules, we obtained a yeast mutant capable of producing IET up to 1.04 g/L through fed-batch fermentation, a ~ 650-fold improvement over the wild-type strain. Besides, our engineering process also revealed many insights about the regulation of AAAs metabolism in S. cerevisiae. Finally, during our engineering process, we also discovered yeast mutants that accumulate anthranilate and L-tryptophan, both of which are precursors of various valuable secondary metabolites from fungi and plants. These strains could be developed to the chassis for natural product biosynthesis upon introducing heterologous pathways.

Visible light-induced cascade sulfonylation/annulation of ortho-allyloxy chalcones with sodium sulfinates for the synthesis of sulfonated chromane derivatives

A visible-light-induced radical cascade reaction for the synthesis of structurally diverse sulfonated chromanes is described. The protocol involves the addition of sulfonyl radicals to ortho-allyloxy chalcones and intramolecular Michael addition reactions in the presence of eosin Y as a photocatalyst. Additionally, this protocol shows that it is also an effective method to construct seven-membered oxygen-containing heterocycles. The method features a wide substrate scope, the use of easily accessible materials and excellent functional group tolerance with high to excellent yields. Control experiments and mechanistic studies indicate that a visible light-induced radical cascade process is involved in the transformation.

Assessment of pharmacokinetic and pharmacodynamic interactions between zavegepant and sumatriptan: A phase 1, randomized, placebo-controlled study in healthy adults

OBJECTIVE

To evaluate the pharmacodynamic (PD) and pharmacokinetic (PK) interactions between zavegepant and sumatriptan in healthy adults.

BACKGROUND

Zavegepant is a high-affinity, selective, small-molecule calcitonin gene-related peptide receptor antagonist administered as a nasal spray approved in the United States for the acute treatment of migraine. Triptans, including sumatriptan, are a different class of drugs for acute migraine treatment and are associated with a risk of increased blood pressure (BP). Hence, it is important to study the drug-drug interactions between zavegepant and sumatriptan due to potential coadministration in clinical settings.

METHODS

This was a Phase 1, single-center, partially blind, randomized, placebo-controlled, single-arm study. Eligible participants were males aged ≥ 18 and ≤ 40 years or females aged ≥ 18 and ≤ 50 years. On Day 1, participants received sumatriptan 2 × 6 mg subcutaneous injections (1 h apart) and were then randomized (6:1 ratio) to receive zavegepant 2 × 10 mg nasal spray (1 in each nostril) or placebo on Days 2 and 3. On Day 4, zavegepant or placebo was coadministered with sumatriptan after the second sumatriptan injection. BP, PK, and safety were evaluated at pre-specified time points.

RESULTS

Forty-two participants enrolled in the study received at least one dose of any treatment and were included in the safety analyses. Forty-one participants who completed the study were included in the BP and PK analyses. The mean (standard deviation) time-weighted average (TWA) of mean arterial pressure (MAP [sumatriptan + zavegepant 87.2 (6.8) vs. sumatriptan 86.9 (6.0)]), diastolic BP (DBP [sumatriptan + zavegepant 72.3 (6.8) vs. sumatriptan 72.1 (6.2)]), and systolic BP (SBP [sumatriptan + zavegepant 116.8 (10.2) vs. sumatriptan 116.2 (8.6)]) did not change following zavegepant and sumatriptan coadministration on Day 4 compared to sumatriptan alone on Day 1. Statistical comparisons of the TWA of MAP, DBP, and SBP between sumatriptan and zavegepant coadministration and sumatriptan alone were similar; the differences observed were 0.04 mmHg for MAP (90% confidence interval [CI]: -0.69, 0.77 mmHg), 0.00 mmHg for DBP (90% CI: -0.76, 0.76 mmHg), and 0.33 mmHg for SBP (90% CI: -0.97, 1.63 mmHg). Sumatriptan PK after sumatriptan and zavegepant coadministration versus sumatriptan alone was similar; the comparison ratios were 102.5% (90% CI: 100.7%, 104.2%) for AUC0-inf and 104.1% (90% CI: 98.0%, 110.6%) for Cmax. A small difference in zavegepant PK exposure after sumatriptan and zavegepant coadministration versus zavegepant alone was not considered clinically relevant: the comparison ratios were 112.4% (90% CI: 103.4%, 122.3%) for AUC0-24 and 96.7% (90% CI: 88.9%, 105.2%) for Cmax. Overall, 90% (38/42) of participants experienced ≥ 1 treatment-emergent adverse event that was mild or moderate in severity. All treatments were generally safe and well tolerated.

CONCLUSION

Coadministration of zavegepant with sumatriptan was safe and without PD or PK interactions in healthy adults.

Efficacy and Safety of Rimegepant 75 mg Oral Tablet, a CGRP Receptor Antagonist, for the Acute Treatment of Migraine: A Randomized, Double-Blind, Placebo-Controlled Trial

Purpose

This study compared the efficacy, tolerability, and safety of rimegepant 75 mg oral tablet - a small molecule calcitonin-gene receptor peptide (CGRP) receptor antagonist - with placebo in the acute treatment of migraine.

Methods

This double-blind, randomized, placebo-controlled trial enrolled adults aged ≥18 years with at least a 1-year history of migraine. Participants randomized to rimegepant 75 mg oral tablet or placebo treated a single migraine attack of moderate or severe pain intensity. The coprimary endpoints, pain freedom and freedom from the most bothersome symptom ([MBS] nausea, photophobia, or phonophobia) at 2 hours postdose, were evaluated using Mantel-Haenszel risk estimation.

Results

Of the 1485 participants enrolled, 1162 (78.2%) were randomized to rimegepant (n = 582) or placebo (n = 580). Most participants (85.5%) were female; the population had a mean (SD) age of 41.6 (12.2) years and a history of 4.7 (1.8) migraine attacks per month. At 2 hours postdose, rimegepant-treated participants had higher pain freedom rates (19.2% [104/543] vs 14.2% [77/541]; risk difference 4.9; 95% confidence interval [CI] 0.5 to 9.3; P=0.0298) and MBS freedom rates (36.6% [199/543] vs 27.7% [150/541]; risk difference 8.9; 95% CI 3.4 to 14.4; P=0.0016) than placebo-treated participants. Rimegepant-treated participants also had higher rates of pain relief (56.0% [304/543] vs 45.7% [247/541]; risk difference 10.3; 95% CI 4.4 to 16.2, P=0.0006) at 2 hours postdose. The most common adverse events were nausea (0.9% [5/546] vs 1.1% [6/549]) and dizziness (0.7% [4/546] vs 0.4% [2/549]). No signal of drug-induced liver injury due to rimegepant was identified.

Conclusion

Rimegepant 75 mg oral tablet was effective in the acute treatment of migraine. Tolerability and safety were similar to placebo, with no evidence of hepatotoxicity.

Trial Registration

Clinicaltrials.gov Identifier: NCT03235479.

Triptans in the Acute Migraine Management of Children and Adolescents: An Update

PURPOSE OF REVIEW

To summarize recent findings regarding triptan use in the acute treatment of pediatric migraine.

RECENT FINDINGS

Prevalence of pediatric migraine is rising. The American Headache Society and American Academy of Neurology updated guidelines to provide evidence-based recommendations for the treatment of acute migraine in youth. In the setting of a dearth of new randomized controlled trials (RCTs), we review current guidelines, triptan use in the emergency department, and an era of secondary analyses. Measuring the efficacy of triptans in pediatric migraine has been challenged by high placebo response rates. Secondary analyses, combining data from multiple RCTs, support that triptans are safe and effective in the treatment of migraine. Triptans are a vital tool and the only FDA-approved migraine-specific treatment available in pediatrics. There is a need for further studies and funding support in pediatric headache medicine.

PACAP-38 related modulation of the cranial parasympathetic projection: A novel mechanism and therapeutic target in severe primary headache

BACKGROUND AND PURPOSE

Little is known of how cranial autonomic symptoms (CAS) in cluster headache and migraine may contribute to their severe headache phenotype. This strong association suggests the involvement of the cranial parasympathetic efferent pathway. To investigate its contribution, we studied the role of pituitary adenylate cyclase activating polypeptide-38 (PACAP-38), a potent sensory and parasympathetic neuropeptide, in modulating pre- and post-ganglionic cranial parasympathetic projection neurons, and their influence on headache-related trigeminal-autonomic responses.

EXPERIMENTAL APPROACH

Using PACAP-38 and PACAP-38 responsive receptor antagonists, electrophysiological, behavioural and facial neurovascular-blood flow was measured in rats to probe trigeminal- and parasympathetic-neuronal, periorbital thresholds and cranial-autonomic outcomes, as they relate to primary headaches.

KEY RESULTS

Sumatriptan attenuated the development of PACAP-38 mediated activation and sensitization of trigeminocervical neurons and related periorbital allodynia. PACAP-38 also caused activation and enhanced responses of dural-responsive pre-ganglionic pontine-superior salivatory parasympathetic neurons. Further, the PACAP-38 responsive receptor antagonists dissected a role of VPAC1 and PAC1 receptors in attenuating cranial-autonomic and trigeminal-neuronal responses to activation of the cranial parasympathetic projection, which requires post-ganglionic parasympathetic neurotransmission.

CONCLUSION AND IMPLICATIONS

Given the prevailing view that sumatriptan acts to some degree via a peripheral mechanism, our data support that PACAP-38 mediated receptor activation modulates headache-related cranial-autonomic and trigeminovascular responses via peripheral and central components of the cranial parasympathetic projection. This provides a mechanistic rationale for the association of CAS with more severe headache phenotypes in cluster headache and migraine, and supports the cranial parasympathetic projection as a potential novel locus for treatment by selectively targeting PACAP-38 or PACAP-38 responsive VPAC1 /PAC1 receptors.

The history and rationale of the development of new drugs for migraine treatment

Migraine is one of the most prevalent and disabling diseases in the world. Migraine attack treatments and prophylactic treatments of this disease are essential to lessen its individual, social, and economic impact. This is a narrative review of the main drugs used for treating migraine, as well as the experimental models and the theoretical frameworks that led to their development. Ergot derivatives, triptans, non-steroid anti-inflammatory drugs, tricyclic antidepressants, beta-blockers,: flunarizine,: valproic acid,: topiramate, onabotulinumtoxin A, ditans, monoclonal antibodies against CGRP and its receptor, and gepants are discussed. Possible therapeutic targets for the development of new drugs that are under development are also addressed. Many of the drugs currently in use for treating migraine were developed for the treatment of other diseases, but have proven effective for the treatment of migraine, expanding knowledge about the disease. With a better understanding of the pathophysiology of migraine, new drugs have been and continue to be developed specifically for the treatment of this disease.

Tryptamine: A privileged scaffold for the management of Alzheimer's disease

Alzheimer's disease (AD) is a chronic and irreversible neurodegenerative disease associated with aging. It is characterized by the progressive loss of memory and other cognitive functions. Although the exact etiology of AD is not well explored, several factors, such as the deposition of amyloid-β (Aβ) plaques, hyperphosphorylation of tau protein, presence of low levels of acetylcholine, and generation of oxidative stress, are key mediators in the progression of AD. Currently, the clinical treatment options for AD are limited and are based on cholinesterase (ChE) inhibitors (e.g., donepezil, rivastigmine, and galantamine), N-methyl- d-aspartic acid receptor antagonists (e.g., memantine), and the recently approved Aβ modulator (e.g., aducanumab). Tryptamine (2-(1H-indol-3-yl)ethan-1-amine) is a small molecule that contains an indole nucleus and an ethylamine side chain. It is also the active metabolite of tryptophan. It possesses a wide range of biological activities related to neurodegenerative disorders, such as ChE inhibition, Aβ aggregation inhibition, antioxidant effects, monoamine-oxidase inhibition, and neuroprotection. Several tryptamine-based hybrid analogs are currently being investigated as multifunctional agents for the development of novel hybrids for AD treatment. Thus, this review article aims to provide in-depth insights into the research progress and strategies for designing multifunctional agents used in Alzheimer's therapy.

Triptans utilization in Italian population: A real-life study in community pharmacies

The term Headache Disorders (HD) refers to a number of nervous system pathologies characterised by recurrent headaches. Despite the serious impact HD have on the health system, society, and the economy, these are an underestimated, underdiagnosed, and, hence, undertreated phenomenon. Triptans are the first-line therapy for the acute treatment of moderate to severe migraine but their utilization is still inadequate, perhaps also because in Italy no triptan can be bought without a medical prescription. In this article, the data from a 2016-2017 study has been further analysed with the aim of evaluating any associations between the use of triptans and the other series of variables identified in the questionnaire. This further analysis has been connected to the role that community pharmacies could play on this issue. The questionnaire was administered to 4,424 pharmacy users by 610 purposely trained pharmacists working in 514 pharmacies. The survey was carried out in 19 of the 20 Italian regions. The data shows that only 25% of patients suffering from HDs are prescribed triptans. Older patients, those with definite migraines, and those with a chronic disorder resort more frequently to this class of pharmaceuticals, as do those patients in care at a specialist headache centre. The multivariable analysis also confirmed these results. Our study, which performed a direct detection, in real life, on patients requesting pharmacological treatment for a migraine headache, therefore confirmed the need to investigate the reasons behind the low use and prescription of triptans in the Italian population. Moreover, any future studies should take advantage of community pharmacies, plan actions that would allow a series of evaluations over time of the requirements of migraineurs, and establish a process to put these patients under the care of the pharmacy to ensure adherence to therapy.

Migraine drugs

According to recent studies, migraine affects more than 1 billion people worldwide, making it one of the world’s most prevalent diseases. Although this highly debilitating illness has been known since ancient times, the first therapeutic drugs to treat migraine, ergotamine (Gynergen) and dihydroergotamine (Dihydergot), did not appear on the market until 1921 and 1946, respectively. Both drugs originated from Sandoz, the world’s leading pharmaceutical company in ergot alkaloid research at the time. Historically, ergot alkaloids had been primarily used in obstetrics, but with methysergide (1-methyl-lysergic acid 1′-hydroxy-butyl-(2S)-amide), it became apparent that they also held some potential in migraine treatment. Methysergide was the first effective prophylactic drug developed specifically to prevent migraine attacks in 1959. On the basis of significantly improved knowledge of migraine pathophysiology and the discovery of serotonin and its receptors, Glaxo was able to launch sumatriptan in 1992. It was the first member from the class of triptans, which are selective 5-HT1B/1D receptor agonists. Recent innovations in acute and preventive migraine therapy include lasmiditan, a selective 5-HT1F receptor agonist from Eli Lilly, the gepants, which are calcitonin gene-related peptide (CGRP) receptor antagonists discovered at Merck & Co and BMS, and anti-CGRP/receptor monoclonal antibodies from Amgen, Pfizer, Eli Lilly, and others.

Graphical abstract

Switching anti-CGRP(R) monoclonal antibodies in multi-assessed non-responder patients and implications for ineffectiveness criteria: A retrospective cohort study

BACKGROUND

A pharmacological class effect was initially proposed for monoclonal antibodies against the calcitonin gene related peptide pathway. However, preliminary evidence shows that switching patients who were non-responding to one monoclonal antibody to another could provide some benefit. Herein, we assess treatment response to an anti-calcitonin gene related peptide/receptor monoclonal antibody in patients who have failed to respond to anti-calcitonin gene related peptide/ligand monoclonal antibodies calcitonin gene related peptide/ligand monoclonal antibodies and vice versa. In addition, we select non-responders to the first anti- monoclonal antibody by three or five more stringent variables.

METHODS

Retrospective cohort study including outpatients treated consecutively with two anti-calcitonin gene related peptide monoclonal antibodies. Ineffectiveness to the first monoclonal antibody was assessed using three (MIDAS score, monthly headache days, and analgesic monthly days) variables or five (monthly headache days, MIDAS score, analgesic monthly days, analgesic monthly number and HIT-6 score) variables in the same cohort of patients. The primary endpoints were the absolute change from baseline in monthly headache days, response rate, and persistence in medication overuse at three months of treatment with the second anti-CGRP mAb.

RESULTS

In patients selected by three variables, a sustained reduction in monthly headache days, analgesic monthly days, MIDAS and HIT-6 scores was observed at month-3 of treatment with the second monoclonal antibody. Ten (45.4%) patients achieved at least a ≥30% response rate. No difference was reported switching anti-CGRP mAb against ligand or receptor. In the patient subgroup selected by five variables, only HIT-6 was reduced from baseline at month-3. However, a trend toward a reduction in monthly headache days, analgesic monthly days, and MIDAS score was observed at month-3.

CONCLUSIONS

Switching anti-calcitonin gene related peptide monoclonal antibodies in selected patients might be an option to achieve or improve clinical benefit. More studies are required to establish the effectiveness of switching these treatments.

Safety, tolerability, and efficacy of zavegepant 10 mg nasal spray for the acute treatment of migraine in the USA: a phase 3, double-blind, randomised, placebo-controlled multicentre trial

BACKGROUND

Intranasal formulations can provide treatment options for people with migraine in whom oral drugs are ineffective, slow-acting, or intolerable because of nausea and vomiting. Zavegepant, an intranasally administered small molecule calcitonin gene-related peptide (CGRP) receptor antagonist, was previously assessed in a phase 2/3 trial. This phase 3 trial aimed to compare the efficacy, tolerability, safety, and timecourse of response for zavegepant nasal spray with placebo in the acute treatment of migraine.

METHODS

This double-blind, randomised, placebo-controlled, multicentre phase 3 trial, conducted at 90 academic medical centres, headache clinics, and independent research facilities in the USA, recruited adults (aged ≥18 years) with a history of two to eight moderate or severe migraine attacks per month. Participants were randomly assigned (1:1) to zavegepant 10 mg nasal spray or matching placebo and self-treated a single migraine attack of moderate or severe pain intensity. Randomisation was stratified by the use or non-use of preventive medication. Study centre personnel entered eligible participants into the study using an interactive web response system that was operated and managed by an independent contract research organisation. All participants, investigators, and the funder were masked to group assignment. The coprimary endpoints, freedom from pain and freedom from the most bothersome symptom at 2 h after the treatment dose, were assessed in all randomly assigned participants who took the study medication, had a migraine attack of moderate or severe pain intensity at baseline, and provided at least one evaluable post-baseline efficacy datapoint. Safety was analysed in all randomly assigned participants who received at least one dose. The study is registered with ClinicalTrials.gov, number NCT04571060, and is closed to accrual.

FINDINGS

Between Oct 27, 2020, and Aug 20, 2021, 1978 participants were recruited and assessed for eligibility. 1405 participants were eligible (703 were assigned to zavegepant and 702 to placebo), and 1269 were included in the efficacy analysis set (623 in the zavegepant group and 646 in the placebo group). 2 h after the treatment dose, more participants in the zavegepant group than in the placebo group had pain freedom (147 [24%] of 623 participants vs 96 [15%] of 646 participants, risk difference 8·8 percentage points, 95% CI 4·5-13·1; p<0·0001) and freedom from their most bothersome symptom (247 [40%] vs 201 [31%], risk difference 8·7 percentage points, 3·4-13·9; p=0·0012). The most common adverse events in either treatment group (≥2%) were dysgeusia (129 [21%] of 629 in the zavegepant group vs 31 [5%] of 653 in the placebo group), nasal discomfort (23 [4%] vs five [1%]), and nausea (20 [3%] vs seven [1%]). No signal of hepatotoxicity due to zavegepant was identified.

INTERPRETATION

Zavegepant 10 mg nasal spray was efficacious in the acute treatment of migraine, with favourable tolerability and safety profiles. Additional trials are needed to establish the long-term safety and consistency of effect across attacks.

FUNDING

Biohaven Pharmaceuticals.

Photoinduced Vicinal 1,2-Difunctionalization of Olefins for the Synthesis of Alkyl Sulfonamides

Alkyl sulfonamides are an important class of bioactive molecules. Historical syntheses have relied on multistep sequences incorporating harsh reaction conditions. Photochemical methods have been limited to hydrosulfamoylation, installing only one substituent across an olefin. Herein, radical/polar crossover (RPC) is used to establish the first multicomponent 1,2-difunctionalization reaction incorporating a sulfonamide moiety and a second reaction partner. This protocol, exemplified on a range of olefins, utilizes various commercial sulfamoyl chlorides and organotrifluoroborates as coupling partners.

Lewis Acid-Promoted Three-Component Cyclization for the Construction of Functionalized Oxazoles

A simple and efficient synthetic strategy from amides, ynals, and sodium sulfinates via a Lewis acid-promoted three-component reaction has been reported. Thus, a broad range of various aryl (not alkyl)-substituted oxazoles could be synthesized via the formation of C-N, C-O, and C-S bonds in a one-pot process. In addition, this reaction possesses other unique advantages, such as transition metal-free catalysis, high step economy, good functional group tolerance, and good regioselectivity.

Drugs and Conditions That May Mimic Hemolysis

OBJECTIVES

Visual inspection of posttransfusion plasma for hemolysis is a key laboratory method in the investigation of possible acute hemolytic transfusion reactions (AHTRs). Many substances and physiologic conditions can mimic hemolysis in vitro. Isolated reports describe specific cases of interference, but a comprehensive listing is lacking.

METHODS

Using an illustrative case, we summarize available literature on substances and conditions that may mimic hemolysis in vitro. We further describe other substances and conditions that may discolor plasma but are unlikely to be mistaken for hemolysis on visual inspection.

RESULTS

At least 11 substances and conditions have been reported to discolor plasma, in colors ranging from orange to red to brown, including relatively common therapies (eg, eltrombopag, hydroxocobalamin, iron dextran). Other substances are unlikely to be encountered in everyday practice but may mimic hemolysis in particular patient populations. Additional substances may cause plasma discoloration, ranging from blue to green to white, and are associated with a wide variety of therapies and conditions.

CONCLUSIONS

An awareness of the possible preanalytic confounding factors that may mimic hemolysis can aid in the workup of a suspected AHTR. Review of the medical record, use of ancillary testing, and consideration for nonimmune causes of hemolysis can aid in ruling out AHTR.

Variability in recurrence rates with acute treatments for migraine: why recurrence is not an appropriate outcome measure

BACKGROUND

Headache recurrence is a common feature of acute therapies, whether approved or still in development, and continues to be a significant problem for both the patient and the clinician. Further complicating this issue is lack of standardization in definitions of recurrence used in clinical trials, as well as disparity in patient characteristics, rendering a comparison of different acute medications challenging. Recurrence has serious clinical implications, which can include an increased risk for new-onset chronic migraine and/or development of medication overuse headache. The aim of this review is to illustrate variability of recurrence rates depending on prevailing definitions in the literature for widely used acute treatments for migraine and to emphasize sustained response as a clinically relevant endpoint for measuring prolonged efficacy. BODY: A literature search of PubMed for articles of approved acute therapies for migraine that reported recurrence rates was performed. Study drugs of interest included select triptans, gepants, lasmiditan, and dihydroergotamine mesylate. An unpublished post hoc analysis of an investigational dihydroergotamine mesylate product that evaluated recurrence rates using several different definitions of recurrence common in the literature is also included. Depending on the criteria established by the clinical trial and the definition of recurrence used, rates of recurrence vary considerably across different acute therapies for migraine, making it difficult to compare results of different trials to assess the sustained (i.e., over a single attack) and the prolonged (i.e., over multiple attacks) efficacy of a particular study medication.

CONCLUSION

A standardized definition of recurrence is necessary to help physicians evaluate recurrence rates of different abortive agents for migraine. Sustained pain relief or freedom may be more comprehensive efficacy outcome measures than recurrence. Future efficacy studies should be encouraged to use the recommended definition of sustained pain freedom set by the International Headache Society.

A Halogen-Atom Transfer (XAT)-Based Approach to Indole Synthesis Using Aryl Diazonium Salts and Alkyl Iodides

Indoles are among the most important N-heterocycles in pharmaceuticals. Here, we present an alternative to the classic Fischer indole synthesis based on the radical coupling between aryl diazoniums and alkyl iodides. This iron-mediated strategy features a double role for the aryl diazoniums that sequentially activate the alkyl iodides through halogen-atom transfer and then serve as radical acceptors. The process operates under mild conditions and enables the preparation of densely functionalized indoles.

European Headache Federation (EHF) consensus on the definition of effective treatment of a migraine attack and of triptan failure

Background

Triptans are migraine-specific acute treatments. A well-accepted definition of triptan failure is needed in clinical practice and for research. The primary aim of the present Consensus was to provide a definition of triptan failure. To develop this definition, we deemed necessary to develop as first a consensus definition of effective treatment of an acute migraine attack and of triptan-responder.

Main body

The Consensus process included a preliminary literature review, a Delphi round and a subsequent open discussion. According to the Consensus Panel, effective treatment of a migraine attack is to be defined on patient well-being featured by a) improvement of headache, b) relief of non-pain symptoms and c) absence of adverse events. An attack is considered effectively treated if patient’s well-being, as defined above, is restored within 2 hours and for at least 24 hours. An individual with migraine is considered as triptan-responder when the given triptan leads to effective acute attack treatment in at least three out of four migraine attacks. On the other hand, an individual with migraine is considered triptan non-responder in the presence of failure of a single triptan (not matching the definition of triptan-responder). The Consensus Panel defined an individual with migraine as triptan-resistant in the presence of failure of at least 2 triptans; triptan refractory, in the presence of failure to at least 3 triptans, including subcutaneous formulation; triptan ineligibile in the presence of an acknowledged contraindication to triptan use, as specified in the summary of product characteristics.

Conclusions

The novel definitions can be useful in clinical practice for the assessment of acute attack treatments patients with migraine. They may be helpful in identifying people not responding to triptans and in need for novel acute migraine treatments. The definitions will also be of help in standardizing research on migraine acute care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01502-z.

Value of Combination Therapy With Antiepileptic Drugs (AEDs) for Migraine to Prevent Ischemic Stroke in Young Women

The aim of this study was to systematically assess the efficacy of a combination of levetiracetam and sumatriptan as a preventive treatment for migraine and stroke in young women.

This was a retrospective study with 342 female patients, who experienced migraines. All patients were divided into three groups: Group A (124 patients (36.2%) with triptan (sumatriptan) monotherapy), Group B (111 patients (32.4%) with a combined triptan and antiepileptic drug (AED) therapy with levetiracetam (LEV)), and Group C (107 (31.2%) patients with placebo treatment), in a 1.4:1.1:1 ratio respectively.

Significant differences were found in Group B when compared with Groups A and C with respect to the use of combination hormonal contraception, smoking, a family history of migraine, and seizures.

The results of this study suggested that combination treatment with levetiracetam and sumatriptan was more effective in preventing migraines and reducing the risk of stroke in young women than sumatriptan monotherapy.

Rongalite as C1 Synthon and Sulfone Source: A Practical Sulfonylmethylation Based on the Separate-Embedding Strategy

Rongalite has been used in several challenging synthetic transformations with operationally simple and effective protocols. However, the employment of multiple characteristics of rongalite in synthetic chemistry is comparatively little known. Herein we report a separate-embedding type sulfonylmethylation of sulfoxonium ylides in which rongalite concurrently acted as a sulfone source, C1 synthon, radical initiator, and potential reducing reagent for the first time. Notably, this facile and easy-handling reaction does not require a catalyst or prefunctionalized sulfonylmethylation reagents.

Design, synthesis and biological evaluation of pyridinylmethylenepiperidine derivatives as potent 5-HT1F receptor agonists for migraine therapy

Migraine is a common neurovascular disease which has been classified as the sixth most disabling disorder. Current migraine therapy was triptans, however, riptans can cause contraction of blood vessels. Therefore, novel drugs without cardiovascular effects emerged, such as CGRP and selective 5-HT1F receptor agonists. In this work, a series of pyridinylmethylenepiperidine derivatives were designed, synthesized and evaluated for their 5-HT1F receptor agonist activity. The results in vitro showed that compound C1-C6 displayed potent agonist activities compared with positive drug lasmiditan. Pharmacokinetic properties in rat indicated that 2,4,6-trifluoro-N-(6-(fluoro(1-methylpiperidin-4-ylidene)methyl)pyridin-2-yl)benzamide (C5) possessed high AUC and good bioavailability. In two rodent models of migraine, C5 significantly inhibited dural plasma protein extravasation and c-fos expression in the trigeminal nucleus caudalis. Moreover, C5 showed no effect on vasoconstriction. Through these studies, we identified C5 as a potent 5-HT1F receptor agonist for migraine therapy.

Palladium-Catalyzed Methylsulfonylation of Alkyl Halides Using Dimethyl Sulfite as SO2 Surrogate and Methyl Source

A novel and efficient method for the synthesis of methyl sulfone derivatives via palladium-catalyzed methylsulfonylation of alkyl halides with dimethyl sulfite has been described. A variety of aryl and alkyl iodides underwent the sulfonylation smoothly to furnish methyl sulfites in moderate to excellent yields.

The impact of CGRPergic monoclonal antibodies on prophylactic antimigraine therapy and potential adverse events

Migraine is a prevalent medical condition and the second most disabling neurological disorder. Regarding its pathophysiology, calcitonin gene-related peptide (CGRP) plays a key role, and, consequently, specific antimigraine pharmacotherapy has been designed to target this system. Hence, apart from the gepants, the recently developed monoclonal antibodies (mAbs) are a novel approach to treat this disorder. In this review we consider the current knowledge on the mechanisms of action, specificity, safety, and efficacy of the above mAbs as prophylactic antimigraine agents, and examine the possible adverse events that these agents may trigger. Antimigraine mAbs act as direct scavengers of CGRP (galcanezumab, fremanezumab, and eptinezumab) or against the CGRP receptor (erenumab). Due to their long half-lives, these molecules have revolutionized the prophylactic treatment of this neurovascular disorder. Moreover, because of their physicochemical properties, these agents are hepato-friendly and do not cross the blood-brain barrier (highlighting the relevance of peripheral mechanisms in migraine). Nevertheless, apart from potential cardiovascular side effects, the interaction with AMY₁ receptors and immunogenicity induced by autoantibodies against mAbs could be a concern for the safety of long-term treatment with these molecules.

The locus of Action of CGRPergic Monoclonal Antibodies Against Migraine: Peripheral Over Central Mechanisms

Migraine is a complex neurovascular disorder characterized by attacks of moderate to severe unilateral headache, accompanied by photophobia among other neurological signs. Although an arsenal of antimigraine agents is currently available in the market, not all patients respond to them. As Calcitonin Gene-Related Peptide (CGRP) plays a key role in the pathophysiology of migraine, CGRP receptor antagonists (gepants) have been developed. Unfortunately, further pharmaceutical development (for olcegepant and telcagepant) was interrupted due to pharmacokinetic issues observed during the Randomized Clinical Trials (RCT). On this basis, the use of monoclonal antibodies (mAbs; immunoglobulins) against CGRP or its receptor has recently emerged as a novel pharmacotherapy to treat migraines. RCT showed that these mAbs are effective against migraines producing fewer adverse events. Presently, the U.S. Food and Drug Administration approved four mAbs, namely: (i) erenumab; (ii) fremanezumab; (iii) galcanezumab; and (iv) eptinezumab. In general, specific antimigraine compounds exert their action in the trigeminovascular system, but the locus of action (peripheral vs. central) of the mAbs remains elusive. Since these mAbs have a molecular weight of ∼150 kDa, some studies rule out the relevance of their central actions as they seem unlikely to cross the Blood-Brain Barrier (BBB). Considering the therapeutic relevance of this new class of antimigraine compounds, the present review has attempted to summarize and discuss the current evidence on the probable sites of action of these mAbs.

A Multicenter, Randomized, Double-Blind, Placebo-Controlled Study of the Efficacy, Tolerability, and Safety of Celecoxib Oral Solution (ELYXYB) in Acute Treatment of Episodic Migraine with or without Aura

Background

Safe, effective, oral therapies are needed for acute treatment of migraine. This clinical trial assessed the efficacy, tolerability, and safety of celecoxib oral solution (ELYXYB) in a single migraine attack associated with moderate-to-severe pain.

Methods

This was a phase III, randomized (1:1), double-blind, placebo-controlled trial, conducted at 41 US centers from December 2016 to October 2017. Adults with episodic migraine (with or without aura) for ≥1 year were treated with a single 4.8 mL dose of 120-mg celecoxib oral solution or placebo. Co-primary endpoints were the proportion of patients who were pain-free and free from the most bothersome migraine symptom (MBS) at 2 hours post-dose. The MBS was identified at screening from among nausea, photophobia, or phonophobia.

Results

Six hundred thirty-one patients were randomized (celecoxib oral solution, n=316; placebo, n=315; mean age 41 years, range 18-75; 84.3% female). One study site met prespecified outlier criteria (defined as a treatment effect estimate that was at least twice as large as all other sites) and was excluded from efficacy analyses. This site had a mean 2-hour pain freedom placebo response rate of 75% vs a combined mean of 23.5% for all other sites. In subsequent analysis, 2-hour post-dose pain freedom response rates were significantly higher in the celecoxib oral solution group vs placebo (32.8%, [27.2%, 38.8%]) vs 23.5%, [18.5%, 29.2%]; P=0.020). For 2-hour post-dose MBS freedom, response rates were significantly higher in the celecoxib oral solution group vs placebo (58.1% [51.4%, 64.5%] vs 43.9% [37.2%, 50.7%]; P=0.003). A total of 10.7% (31/289) of patients treated with celecoxib oral solution and 9.9% (28/283) of placebo-treated patients reported a treatment-emergent adverse event (TEAE). Study drug-related TEAEs were reported by 7.3% (21/289) and 7.4% (21/283) of celecoxib oral solution and placebo patients, respectively; the most common were nausea (celecoxib oral solution: 1.4% [4/289] vs placebo: 1.8% [5/283]) and dysgeusia (celecoxib oral solution: 1.7% [5/289] vs placebo: 1.1% [3/283]). No serious TEAEs, deaths, or drug-related TEAEs leading to withdrawal were reported.

Conclusion

Celecoxib oral solution is a safe, effective COX-2-selective nonsteroidal anti-inflammatory drug for the treatment of acute migraine. In this analysis, celecoxib oral solution was significantly more effective than placebo and was also associated with a low rate of gastric TEAEs. Celecoxib oral solution may provide a convenient, alternate option to currently available treatments.

Trial Registration

ClinicalTrials.gov Identifier: NCT03009019; registered January 4, 2017; retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03009019.

Naratriptan is as effective as sumatriptan for the treatment of migraine attacks when used properly. A mini-review

BACKGROUND

Naratriptan, marketed in a low oral dose of 2.5 mg, is generally regarded as a less-effective triptan with a slower onset of action than most other triptans in the treatment of migraine attacks. In this review, naratriptan will be compared with sumatriptan, the standard triptan.

METHODS

Papers on pharmacodynamics and pharmacokinetics and results from comparative clinical trials with oral and subcutaneous naratriptan versus other triptans were retrieved from PubMed.

RESULTS

Naratriptan and sumatriptan have similar effects in relevant animal models. In a randomized controlled trial, oral naratriptan 2.5 mg is less effective than oral sumatriptan 100 mg after both 2 h and 4 h. In contrast, oral naratriptan 10 mg has a similar time-effect curve as oral sumatriptan 100 mg, in both its steepness and the efficacy at 2 h and 4 h. Subcutaneous naratriptan 10 mg (88% pain free at 2 h) was in one trial superior to subcutaneous sumatriptan 6 mg (55% pain free at 2 h).

CONCLUSION

Naratriptan was marketed for the treatment of migraine attacks as the "gentle triptan" in a low oral dose of 2.5 mg, a dose with no more adverse events than placebo. This low dose results in the slow onset of action and low efficacy of oral naratriptan, but in high doses oral naratriptan is similar to oral sumatriptan. Based on one randomized controlled trial, subcutaneous naratriptan has probably the greatest effect of any triptan.

Pharmacological, Pharmacokinetic, Pharmacodynamic and Physicochemical Characterization of FE 205030: A Potent, Fast Acting, Injectable CGRP Receptor Antagonist for the Treatment of Acute Episodic Migraine

The neuropeptide calcitonin gene-related peptide (CGRP) is known to play a central role in the underlying pathophysiology of migraine. In comparison to the effective triptan class of antimigraine treatments, the CGRP antagonists possess a comparable efficacy but a superior cardiovascular safety profile in patients. This paper describes the development of selective and potent peptidic CGRP antagonist, FE 205030, that has a fast onset of action and an optimal half-life (subcutaneous T_max ~ 60 min, and t_1/2 ~ 4.4 h in 80 kg pigs, respectively), which is key to prevention of the progression of debilitating migraine symptoms. The in vivo efficacy of this agent has been established a translational pharmacodynamic model (inhibition of capsaicin-induced increase in skin blood flow) in cynomolgus monkeys and shows maximal inhibitory activity at circulating concentrations of 30-100 nM. Antagonist activity of FE 205030 was characterized on CGRP-induced vasodilation in isolated human mesenteric resistance arteries in an ex vivo isometric myograph study, and FE 205030 effectively blocked CGRP-induced vasodilation with a pA₂ of 9.3 ± 0.1, mean ± standard error. Multispecies allometric scaling and modeling of subcutaneous (SC) effective concentrations indicates that a dose of 10-30 mg/day is sufficient to achieve a drug exposure/target coverage of 8h, which is useful to prevent migraine recurrence in patients. The molecule also possesses appropriate physicochemical properties that allows for a convenient dosing form factor of 1 ml injection volume with a sufficient solubility and acceptable short-term stability, optimal for treatment of acute migraine episodes in patients. Hence, FE 205030 may provide an important fast-acting injectable option for patients suffering from frequent acute migraine episodes, complementary to preventative monoclonal antibodies and oral small molecule CGRP-R antagonist therapies.

Genetics, pathophysiology, diagnosis, treatment, management, and prevention of migraine

Migraine is a neurological ailment that is characterized by severe throbbing unilateral headache and associated with nausea, photophobia, phonophobia and vomiting. A full and clear mechanism of the pathogenesis of migraine, though studied extensively, has not been established yet. The current available information indicates an intracranial network activation that culminates in the sensitization of the trigemino-vascular system, release of inflammatory markers, and initiation of meningeal-like inflammatory reaction that is sensed as headache. Genetic factors might play a significant role in deciding an individual's susceptibility to migraine. Twin studies have revealed that a single gene polymorphism can lead to migraine in individuals with a monogenic migraine disorder. In this review, we describe recent advancements in the genetics, pathophysiology, diagnosis, treatment, management, and prevention of migraine. We also discuss the potential roles of genetic and abnormal factors, including some of the metabolic triggering factors that result in migraine attacks. This review will help to accumulate current knowledge about migraine and understanding of its pathophysiology, and provides up-to-date prevention strategies.

Migraine neuroscience: from experimental models to target therapy

Migraine sciences have witnessed tremendous advances in recent years. Pre-clinical and clinical experimental models have contributed significantly to provide useful insights into the brain structures that mediate migraine attacks. These models have contributed to elucidate the role of neurotransmission pathways and to identify the role of important molecules within the complex network involved in migraine pathogenesis. The contribution and efforts of several research groups from all over the world has ultimately lead to the generation of novel therapeutic approaches, specifically targeted for the prevention of migraine attacks, the monoclonal antibodies directed against calcitonin gene-related peptide or its receptor. These drugs have been validated in randomized placebo-controlled trials and are now ready to improve the lives of a large multitude of migraine sufferers. Others are in the pipeline and will soon be available.

Drug interactions and risks associated with the use of triptans, ditans and monoclonal antibodies in migraine

PURPOSE OF REVIEW

The aim of this study was to review current evidence concerning potential risks and interactions associated with concomitant use of drugs indicated for the abortive treatment of migraine, namely triptans and ditans, and more recently developed drugs used for the preventive treatment. The latter drug class encompasses monoclonal antibodies (mAbs), which target either calcitonin gene-related peptide (CGRP) or its receptor.

RECENT FINDINGS

To date, no pharmacokinetic interactions between these drug classes have been reported. However, patients who suffer from triptan- (or ditan-) induced medication overuse headache or those who are nonresponders to triptans might respond less effectively to mAbs. Caution is warranted when coadministrating these drugs in migraine patients with comorbid cardiovascular disease or with an increased cardiovascular risk profile.

SUMMARY

In this review, the main mechanisms of action of triptans, ditans and mAbs targeting CGRP or its receptor are summarized as well as the current evidence on their individual risks. Studies on risks and interactions in case of concomitant use of triptans, ditans and mAbs in migraine patients are relatively scarce. Therefore, these aspects have been considered from a theoretical and hypothetical point of view by taking both their overlapping target, CGRP, and contraindications into account.

Early treatment with sumatriptan prevents PACAP38-induced migraine: A randomised clinical trial

OBJECTIVE

To determine whether early treatment with sumatriptan can prevent PACAP38-induced migraine attacks.

METHODS

A total of 37 patients with migraine without aura were enrolled between July 2018 to December 2019. All patients received an intravenous infusion of 10 picomole/kg/min of PACAP38 over 20 min followed by an intravenous infusion of 4 mg sumatriptan or placebo over 10 min on two study days in a randomised, double-blind, placebo-controlled, crossover study.

RESULTS

Of 37 patients enrolled, 26 (70.3%) completed the study and were included in analyses. Of the 26 patients, four (15%) developed a PACAP38-induced migraine attack on sumatriptan and 11 patients (42%) on placebo (p = 0.016). There were no differences in area under the curve for headache intensity between sumatriptan (mean AUC 532) and placebo (mean AUC 779) (p = 0.35). Sumatriptan significantly constricted the PACAP38-dilated superficial temporal artery immediately after infusion (T30) compared with infusion of placebo (p < 0.001).Conclusions and relevance: Early treatment with intravenously administered sumatriptan prevented PACAP38-induced migraine. Prevention of migraine attacks was associated with vasoconstriction by sumatriptan in the earliest phases of PACAP provocation. These results suggest that sumatriptan prevents PACAP38-induced migraine by modulation of nociceptive transmission within the trigeminovascular system.Trial Registration: ClinicalTrials.gov (NCT03881644).

Headaches in Adults in Primary Care: Evaluation, Diagnosis, and Treatment

Headaches are common in primary care. The diagnosis is made by a careful history and physical examination. Imaging is generally not warranted. Several general principles underlie the acute treatment of headache: early initiation of therapy and adequate dosing at first dose. Careful attention to avoiding too frequent administration of acute therapy is important to avoid medication overuse headaches. Opioids should always be avoided. Preventive treatment is indicated for frequent headaches. Successful treatment entails low-dose medication with careful titration and monitoring of headache frequency. Behavioral strategies are important and should be part of any comprehensive headache management plan.

Valproic Acid in the Treatment of Migraines

Migraine headaches can be a disabling condition for patients. Fortunately, most patients can be successfully managed in the outpatient setting, however, there are a number of patients who may not respond to the abortive treatments that they have been prescribed. These patients often present to the emergency department (ED) for further assistance with the management of their condition. Migraines are the fourth most common cause of ED visits and are associated with an estimated annual cost of $17 billion in the United States. Familiarity with abortive treatments is critical for providers in the ED as are treatments, such as valproic acid, that may be considered in patients who do not respond to other treatment options. Many providers are more familiar with the role of valproic acid in the treatment of mood and seizure disorders, but its tolerability and the successes reported in the primary literature make it a reasonable consideration for patients with migraine who fail to respond to other therapies. This article briefly summarizes the therapies considered first line for abortive treatment in the setting of migraines and provides an overview of the primary literature describing the use of valproic acid in these patients.

Pharmacological strategies to treat attacks of episodic migraine in adults

INTRODUCTION

Migraine patients prioritize early complete relief of headache and associated symptoms, sustained freedom of pain, and good tolerability. One major obstacle for the successful use of drug treatment of migraine attack is that the speed of action of triptans, 5-HT_1B/1D receptor agonists, is delayed.

AREAS COVERED

In this review, the author discusses the following features of acute migraine drugs: pharmacology; pharmacokinetics, and absorption of drugs during migraine attacks. Next, dose-response curves for effect; and the delayed onset of action is reviewed. In the more clinical part of the review, the following items are discussed: overall clinical judgments; comparison of triptans; comparison of triptans with NSAIDs; early intervention with triptans; medication-overuse headache; comments on the effect of gepants; and the general principle of acute migraine therapy.

EXPERT OPINION

The delay in the onset of effect of acute migraine drugs is likely due to a complex antimigraine system involving more than one site of action. Investigations into the mechanisms of the delay should have a high priority, both in studies with animals, migraine models, and in migraine patients during attacks. Non-oral administration of antimigraine drugs resulting in early absorption of drugs should be developed as they possibly also can increase E_max.

Risk of Acute Myocardial Infarction, Heart Failure, and Death in Migraine Patients Treated with Triptans

OBJECTIVE

The goal of this study is to determine the strength of association between treatment with triptans and acute myocardial infarction, heart failure, and death.

BACKGROUND

Case reports in the literature have raised concerns over an association between treatment of migraine headaches with triptans and cardiovascular events. This study aims to systematically evaluate this association in a contemporary population-based cohort. We hypothesized that triptan exposure is not associated with increased cardiovascular events.

METHODS

A retrospective cohort study was conducted within an integrated healthcare delivery system in Southern California. From January 2009 to December 2018, 189,684 patients age ≥18 years had a diagnosis of migraine. In this group, 130,656 were exposed to triptans. Patients treated with triptans were matched 1:1 to those not exposed to triptans by using a propensity score. The primary outcome was acute myocardial infarction; secondary outcomes were heart failure, all-cause death, and combined acute myocardial infarction, heart failure, and death.

RESULTS

The incidence rate of acute myocardial infarction was 0.67 per 1000 person-year in triptan-exposed vs 1.44 per 1000 person-year in not exposed patients. In propensity-matched analyses, the adjusted hazard ratio for triptan exposure was 0.95 (95% confidence interval [CI] 0.84-1.08) for acute myocardial infarction; 1.00 (95% CI 0.93-1.08) for all-cause death; 0.93 (95% CI 0.81-1.08) for heart failure; and 0.99 (95% CI 0.93-1.06) for a composite of acute myocardial infarction, heart failure, or death. Sensitivity analyses focusing on stratified subgroups based on age, gender, ethnicity, and several cardiac risk factors also revealed no significant association between triptan exposure and cardiovascular events.

CONCLUSIONS

No association was found between exposure to triptans and an increased risk of cardiovascular events. These data provide reassurance regarding the cardiovascular safety of utilizing triptans for the medical management of migraine headaches.

Base-Mediated Denitrogenative Sulfonylation/Benzannulation of Conjugated N-Sulfonylhydrazones with 3-Formylchromones for the Construction of Polyfunctionalized Biaryl Sulfones

Base-promoted benzannulation of conjugated N-sulfonylhydrazones and 3-formylchromones for the synthesis of diverse biaryl sulfones is described. The approach facilitates new C-C and C-S bond formation via the cascade diazo formation/Michael addition/ring opening/denitrogenative sulfonylation/intramolecular cycloaddition/dehydration and introduces diverse functional groups onto biaryl sulfones. The synthesized compounds are converted to aryl sulfones bearing bioactive benzisoxazole and benzofuran frameworks. Moreover, the synthesized biaryl sulfones possess potent turn-on fluorescence sensing and UV absorbance properties.

Onset of action in placebo-controlled migraine attacks trials: A literature review and recommendation

BACKGROUND

Migraine patients want acute treatment to provide complete relief of the migraine attack within 30 minutes. Traditionally, "speed of onset of effect" is evaluated by estimating the time-point for first statistical separation of drug and placebo. The estimated onset of effect can be a few percent difference of patients being pain free in very large randomised, controlled trials. This difference, however, can be clinically irrelevant.

METHODS

Placebo-controlled randomised, controlled trials with pain freedom results from 30 min to 2-4 hours were retrieved from the literature. For each time-point, the therapeutic gain (drug minus placebo) (TG) was calculated. Therapeutic gain for being pain free of 5% was chosen for the definition of "onset of action", since this is approximately 1/3 of the 16% TG and 1/4 of 21% of TG for sumatriptan 50 mg and 100 mg, respectively.

RESULTS

A total of 22 time-effect curves based on randomised, controlled trials were analysed. Based on the "onset of action" of 5% pain freedom, the evaluated drugs and administration forms can be classified as follows: i) Early time to onset, ≤30 min (three randomised, controlled trials); ii) medium time to onset, 60 min (nine randomised, controlled trials); iii) delayed time to onset, 90-120 min (10 randomised, controlled trials).

CONCLUSION

Only three non-oral administration forms with a triptan (subcutaneous sumatriptan and nasal zolmitriptan) resulted in an "onset of action" at ≥30 min; in the future, early onset of action should be a priority in the development of new drugs or new administration-forms for the treatment of acute migraine attacks.

Continuous Flow Synthesis of Heterocycles: A Recent Update on the Flow Synthesis of Indoles

Indole derivatives are among the most useful and interesting heterocycles employed in drug discovery and medicinal chemistry. In addition, flow chemistry and flow technology are changing the synthetic paradigm in the field of modern synthesis. In this review, the role of flow technology in the preparation of indole derivatives is showcased. Selected examples have been described with the aim to provide readers with an overview on the tactics and technologies used for targeting indole scaffolds.