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Sexton PM, Poyner DR, Simms J, Christopoulos A, Hay DL. RAMPs as drug targets. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 744:61-74. [PMID: 22434108 DOI: 10.1007/978-1-4614-2364-5_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The receptor activity-modifying protein (RAMP) family of membrane proteins regulates G protein-coupled receptor (GPCR) function in several ways. RAMPs can alter their pharmacology and signalling as well as the trafficking of these receptors to and from the cell surface. Accordingly, RAMPs may be exploited as drug targets, offering new opportunities for regulating the function of therapeutically relevant RAMP-interacting GPCRs. For example, several small molecule antagonists of RAMP1/ calcitonin receptor-like receptor complexes, which block the actions of the neuropeptide calcitonin gene-related peptide are in development for the treatment of migraine headache.
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Affiliation(s)
- Patrick M Sexton
- Department of Pharmacology, Monash University, Victoria, Australia
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52
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Geppetti P, Rossi E, Chiarugi A, Benemei S. Antidromic vasodilatation and the migraine mechanism. J Headache Pain 2011; 13:103-11. [PMID: 22200764 PMCID: PMC3274576 DOI: 10.1007/s10194-011-0408-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Accepted: 12/07/2011] [Indexed: 01/07/2023] Open
Abstract
Despite the fact that an unprecedented series of new discoveries in neurochemistry, neuroimaging, genetics and clinical pharmacology accumulated over the last 20 years has significantly increased our current knowledge, the underlying mechanism of the migraine headache remains elusive. The present review article addresses, from early evidence that emerged at the end of the nineteenth century, the role of ‘antidromic vasodilatation’ as part of the more general phenomenon, currently defined as neurogenic inflammation, in the unique type of pain reported by patients suffering from migraine headaches. The present paper describes distinctive orthodromic and antidromic properties of a subset of somatosensory neurons, the vascular- and neurobiology of peptides contained in these neurons, and the clinical–pharmacological data obtained in recent investigations using provocation tests in experimental animals and human beings. Altogether, previous and recent data underscore that antidromic vasodilatation, originating from the activation of peptidergic somatosensory neurons, cannot yet be discarded as a major contributing mechanism of the throbbing head pain and hyperalgesia of migraine.
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Affiliation(s)
- Pierangelo Geppetti
- Headache Centre, Careggi University Hospital, Department of Preclinical and Clinical Pharmacology, University of Florence, Florence, Italy.
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53
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Structural insights into RAMP modification of secretin family G protein-coupled receptors: implications for drug development. Trends Pharmacol Sci 2011; 32:591-600. [DOI: 10.1016/j.tips.2011.05.007] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 05/25/2011] [Accepted: 05/26/2011] [Indexed: 11/18/2022]
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Zartman CB, Bell IM, Gallicchio SN, Graham SL, Kane SA, Mallee JJ, Rutledge RZ, Salvatore CA, Vacca JP, Williams TM. Identification of a novel RAMP-independent CGRP receptor antagonist. Bioorg Med Chem Lett 2011; 21:6705-8. [PMID: 21982500 DOI: 10.1016/j.bmcl.2011.09.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 09/14/2011] [Accepted: 09/15/2011] [Indexed: 10/17/2022]
Abstract
Identification of an HIV integrase inhibitor with micromolar affinity for the CGRP receptor led to the discovery of a series of structurally novel CGRP receptor antagonists. Optimization of this series produced compound 16, a low-molecular weight CGRP receptor antagonist with good pharmacokinetic properties in both rat and dog. In contrast to other nonpeptide antagonists, the activity of 16 was affected by the presence of divalent cations and showed evidence of an alternative, RAMP-independent CGRP receptor binding site.
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Affiliation(s)
- C Blair Zartman
- Department of Medicinal Chemistry, Merck Research Laboratories, West Point, PA 19486, USA.
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Abstract
This article covers the remarkable recent decades as clinicians and scientists have grappled with understanding headache. It is a challenge to understand how a 'normal' brain can become dysfunctional, incapacitating an individual, and then become 'normal' again. Does the answer lie in the anatomy, electrical pathways, the chemistry or a combination? How do the pieces fit together? The components are analyzed in this article. Animal models have provided potential answers. However, these processes have never been proven in man. The dynamic imaging of pain and headache is rapidly evolving and providing new insights and directions of research.
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Van der Schueren BJ, Blanchard R, Murphy MG, Palcza J, De Lepeleire I, Van Hecken A, Depré M, de Hoon JN. The potent calcitonin gene-related peptide receptor antagonist, telcagepant, does not affect nitroglycerin-induced vasodilation in healthy men. Br J Clin Pharmacol 2011; 71:708-17. [PMID: 21480950 DOI: 10.1111/j.1365-2125.2010.03869.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
AIMS To assess the effect of the calcitonin gene-related peptide (CGRP) receptor antagonist, telcagepant, on the haemodynamic response to sublingual nitroglycerin (NTG). METHODS Twenty-two healthy male volunteers participated in a randomized, placebo-controlled, double-blind, two-period, crossover study. Subjects received 500 mg telcagepant or placebo followed, 1.5 h later, by 0.4 mg NTG. To assess the haemodynamic response the following vascular parameters were measured: blood pressure, aortic augmentation index (AIx) and brachial artery diameter (BAD). Data are presented as mean (95% confidence interval, CI). RESULTS The aortic AIx following NTG decreased by -18.50 (-21.02, -15.98) % after telcagepant vs. -17.28 (-19.80, -14.76) % after placebo. The BAD fold increase following NTG was 1.14 (1.12, 1.17) after telcagepant vs. 1.13 (1.10, 1.15) after placebo. For both AIx and BAD, the hypothesis that telcagepant does not significantly affect the changes induced by NTG is supported (P < 0.0001). In addition, no vasoconstrictor effect of telcagepant could be demonstrated. CONCLUSIONS Telcagepant did not affect NTG-induced haemodynamic changes. These data suggest that NTG-induced vasodilation is not CGRP dependent.
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Affiliation(s)
- Bart J Van der Schueren
- Center for Clinical Pharmacology, University Hospital Gasthuisberg (K.U. Leuven), Leuven, Belgium.
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Abstract
Telcagepant (MK0974) is one of several calcitonin-gene-related peptide antagonists in development as a potential treatment for acute migraine attacks and is the first orally available drug in this class. Preclinical and clinical data are reviewed, which support the efficacy and tolerability of telcagepant for the treatment of migraine, particularly for patients unable to tolerate, or who have cardiovascular contraindications to, triptans.
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Affiliation(s)
- E. Anne MacGregor
- The City of London Migraine Clinic, 22 Charterhouse Square, London EC1M 6DX Centre for Neuroscience and Trauma, Blizard Institute of Cell and Molecular Science, Queen Mary, University of London, Barts and the London School of Medicine and Dentistry, London
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Abstract
BACKGROUND The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. Both are effective in migraine but in doses much higher than would be predicted from receptor binding and other in vitro results. This could perhaps suggest an effect of CGRP antagonists behind the blood-brain barrier (BBB), i.e. in the central nervous system (CNS). METHODS Comparison of doses needed for CGRP blocking effect in vitro with dose needed in vivo in man and monkeys. Discussion of these doses in relation to doses needed for anti-migraine activity. RESULTS In vivo studies in monkeys and man showed that high doses compared to doses needed in vitro are needed to block capsaicin-induced in skin blood flow, a CGRP-mediated reaction. These doses are close to those needed for anti-migraine activity. CONCLUSION The apparently high doses of CGRP receptor antagonists, olcegepant and telcagepant needed for anti-migraine effect are not so high after all. They do not allow a conclusion as to whether CGRP antagonists act on peripheral sites or central sites in migraine.
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Potential mechanisms of prospective antimigraine drugs: A focus on vascular (side) effects. Pharmacol Ther 2011; 129:332-51. [DOI: 10.1016/j.pharmthera.2010.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 11/09/2010] [Indexed: 12/13/2022]
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Crystal structure of the ectodomain complex of the CGRP receptor, a class-B GPCR, reveals the site of drug antagonism. Structure 2011; 18:1083-93. [PMID: 20826335 DOI: 10.1016/j.str.2010.05.014] [Citation(s) in RCA: 134] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2010] [Revised: 05/21/2010] [Accepted: 05/25/2010] [Indexed: 11/22/2022]
Abstract
Dysregulation of the calcitonin gene-related peptide (CGRP), a potent vasodilator, is directly implicated in the pathogenesis of migraine. CGRP binds to and signals through the CGRP receptor (CGRP-R), a heterodimer containing the calcitonin receptor-like receptor (CLR), a class B GPCR, and RAMP1, a receptor activity-modifying protein. We have solved the crystal structure of the CLR/RAMP1 N-terminal ectodomain heterodimer, revealing how RAMPs bind to and potentially modulate the activities of the CLR GPCR subfamily. We also report the structures of CLR/RAMP1 in complex with the clinical receptor antagonists olcegepant (BIBN4096BS) and telcagepant (MK0974). Both drugs act by blocking access to the peptide-binding cleft at the interface of CLR and RAMP1. These structures illustrate, for the first time, how small molecules bind to and modulate the activity of a class B GPCR, and highlight the challenges of designing potent receptor antagonists for the treatment of migraine and other class B GPCR-related diseases.
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Medimagh R, Marque S, Prim D, Chatti S. A facile preparation of trisubstituted amino-furan and -thiophene derivatives. Org Biomol Chem 2011; 9:6055-65. [DOI: 10.1039/c1ob05216k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Paone DV, Nguyen DN, Shaw AW, Burgey CS, Potteiger CM, Deng JZ, Mosser SD, Salvatore CA, Yu S, Roller S, Kane SA, Selnick HG, Vacca JP, Williams TM. Orally bioavailable imidazoazepanes as calcitonin gene-related peptide (CGRP) receptor antagonists: discovery of MK-2918. Bioorg Med Chem Lett 2010; 21:2683-6. [PMID: 21251825 DOI: 10.1016/j.bmcl.2010.12.054] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 12/08/2010] [Accepted: 12/13/2010] [Indexed: 11/25/2022]
Abstract
In our ongoing efforts to develop CGRP receptor antagonists for the treatment of migraine, we aimed to improve upon telecagepant by targeting a compound with a lower projected clinical dose. Imidazoazepanes were identified as potent caprolactam replacements and SAR of the imidazole yielded the tertiary methyl ether as an optimal substituent for potency and hERG selectivity. Combination with the azabenzoxazinone spiropiperidine ultimately led to preclinical candidate 30 (MK-2918).
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Affiliation(s)
- Daniel V Paone
- Department of Medicinal Chemistry, Merck Research Laboratories, West Point, PA 19486, USA.
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Han TH, Blanchard RL, Palcza J, Martucci A, Miller-Stein CM, Gutierrez M, Panebianco D, Rippley RK, Lines C, Murphy MG. The Dose Proportionality of Telcagepant after Administration of Single Oral and Intravenous Doses in Healthy Adult Subjects. ACTA ACUST UNITED AC 2010; 3:55-62. [PMID: 21221171 PMCID: PMC3015066 DOI: 10.1111/j.1753-5174.2010.00031.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
INTRODUCTION: Telcagepant (MK-0974) is a novel, orally active and selective CGRP receptor antagonist being investigated for acute treatment of migraine. Early clinical data suggested greater than dose proportional increases in exposure following oral administration. The aim of the present studies was to definitively characterize the oral and IV dose proportionality of telcagepant. METHODS: Healthy adult subjects were enrolled in two separate open-label randomized dose proportionality studies: 1) single oral dose crossover from 50 to 600 mg (N = 19); 2) single IV dose parallel group from 5 to 250 mg (N = 10 per dose). Blood samples were collected at time points from 0 to 48 hours postdose. RESULTS: Telcagepant was rapidly absorbed with a T(max) of approximately 1 to 2 hours after oral administration. The terminal half-life was approximately 8 to 9 hours after IV dosing and approximately 4 to 7 hours after oral dosing. Oral administration of telcagepant resulted in greater than dose proportional increases in exposure, while IV administration resulted in approximately dose proportional increases in exposure. CONCLUSIONS: Telcagepant was generally well tolerated. Oral telcagepant exhibits non-linear pharmacokinetics.
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64
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Ho TW, Olesen J, Dodick DW, Kost J, Lines C, Ferrari MD. Antimigraine efficacy of telcagepant based on patient's historical triptan response. Headache 2010; 51:64-72. [PMID: 21054362 DOI: 10.1111/j.1526-4610.2010.01790.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To evaluate whether the same or different patients respond to triptans and telcagepant. BACKGROUND Telcagepant is an oral calcitonin gene-related peptide receptor antagonist with acute antimigraine efficacy comparable to oral triptans. It is currently unknown whether migraine patients who cannot be adequately helped with triptans might benefit from treatment with telcagepant. METHODS Post-hoc analysis of data from a randomized, controlled trial of telcagepant (150 mg, 300 mg) zolmitriptan 5 mg, or placebo for a moderate/severe migraine. Responder rates were analyzed according to patients' self-reported historical triptan response (HTR): (1) good HTR (N = 660): response in 75-100% of attacks; (2) intermediate HTR (N = 248): response in 25-74% of attacks; (3) poor HTR/no use (N = 407): response in < 25% of attacks, or patient did not take triptans. A limitation of the analysis is that the last subgroup comprised mainly (91%) patients who reported that they did not take triptans, but it was not known whether these patients were triptan-naïve or had previously used triptans and stopped taking them. RESULTS For zolmitriptan, 2-hour pain relief rates were higher in the good HTR subgroup (116/162, 72%) than in the intermediate (29/62, 47%) and poor/no use (44/111, 40%) HTR subgroups. The 2-hour pain relief rates were similar across HTR subgroups for telcagepant 150 mg (48-58%), 300 mg (52-58%), and placebo (26-31%). In the poor/no use HTR subgroup, more patients receiving telcagepant 300 mg (56/98, 57.1%) had 2-hour pain relief than those receiving zolmitriptan (44/111, 39.6%; odds ratio = 2.11 [95% CI: 1.20,3.71], P = .009); the percentage for telcagepant 150 mg (57/119, 47.9%) was not significantly different from zolmitriptan (odds ratio = 1.41 [95% CI: 0.82, 2.40], P = .211). CONCLUSIONS This suggests that different patients may respond to triptans or telcagepant 300 mg. Caution should be exercised in interpreting the results because of the post-hoc nature of the analysis (clinical trial registry: NCT00442936).
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Affiliation(s)
- Tony W Ho
- Merck Research Laboratories, North Wales, PA 19454-1099, USA
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65
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Fischer MJM. Calcitonin gene-related peptide receptor antagonists for migraine. Expert Opin Investig Drugs 2010; 19:815-23. [PMID: 20482328 DOI: 10.1517/13543784.2010.490829] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
IMPORTANCE OF THE FIELD Migraine is a highly prevalent disabling condition, and the current treatment options are not satisfactory. The role of calcitonin gene-related peptide (CGRP) in migraine pathophysiology is well established. CGRP receptor antagonists address this new target and have the potential to improve therapy for both responders and non-responders to previous options. AREAS COVERED IN THIS REVIEW This review describes CGRP, its receptors and their role in the pathophysiology of migraine. CGRP receptor antagonists are a recent development; all reported antagonists are reported in chronological order. The experimental evidence, as well as all clinical trials since the first proof-of-concept study in 2004, is discussed. WHAT THE READER WILL GAIN An overview of the CGRP system and why it provides an attractive drug target for headache. The main focus is on the currently presented CGRP receptor antagonists and clinical evidence for this new therapeutic option. TAKE HOME MESSAGE CGRP receptor antagonists will provide an additional and valuable therapeutic option for the treatment of headaches.
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Comparison of the vasoconstrictor effects of the calcitonin gene-related peptide receptor antagonist telcagepant (MK-0974) and zolmitriptan in human isolated coronary arteries. J Cardiovasc Pharmacol 2010; 55:518-21. [PMID: 20164785 DOI: 10.1097/fjc.0b013e3181d7665f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Studies were conducted in human isolated coronary arteries to explore the vascular effects of the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant and to compare its coronary vasoconstrictive potential to that of zolmitriptan. KCl precontracted coronary vessels were shown to relax to human alphaCGRP, with the CGRP-mediated vasorelaxation completely blocked with 30 microM telcagepant. In coronary vessels at basal tone, zolmitriptan caused a concentration-dependent contraction (pEC50 = 6.9 +/- 0.1; slope 0.94), with the greatest contraction obtained between 1 and 10 microM in most tissues. In contrast, telcagepant at concentrations up to 30 microM evoked no change in contractile tone. These findings suggest the potential for CGRP receptor antagonists to exert antimigraine efficacy in the absence of adverse effects on coronary tone.
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67
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Baraldi PG, Preti D, Materazzi S, Geppetti P. Transient receptor potential ankyrin 1 (TRPA1) channel as emerging target for novel analgesics and anti-inflammatory agents. J Med Chem 2010; 53:5085-107. [PMID: 20356305 DOI: 10.1021/jm100062h] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Pier Giovanni Baraldi
- Department of Pharmaceutical Sciences, Ferrara University, Via Fossato di Mortara 17-19, 44100 Ferrara, Italy.
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68
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Abstract
Although the triptan drugs provide effective relief from migraine for many patients, a substantial number of affected individuals are unresponsive to these compounds, and such therapy can also lead to a range of adverse effects. Telcagepant represents a new class of antimigraine drug-the calcitonin gene-related peptide receptor blockers. This compound exerts its effects by blocking receptors for the calcitonin-gene-related peptide at several sites in the trigeminal and central nervous systems, resulting in pain relief. Telcagepant does not cause vasoconstriction, a major limitation in the use of triptans. Comparisons with triptans in clinical trials for acute treatment of migraine attacks revealed clinical effects similar to those of triptans but better than those of placebo. Telcagepant might provide hope for those who have a poor response to, or are unable to use, older drugs. In patients who need prophylaxis because of frequent attacks of migraine, topiramate is a first-line drug for migraine prevention in many countries; it is generally safe and reasonably well tolerated. Data suggest that topiramate could aid reversion of chronic migraine to episodic migraine.
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Affiliation(s)
- Lars Edvinsson
- Department of Internal Medicine, University Hospital, Lund, Sweden.
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69
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Differential distribution of calcitonin gene-related peptide and its receptor components in the human trigeminal ganglion. Neuroscience 2010; 169:683-96. [DOI: 10.1016/j.neuroscience.2010.05.016] [Citation(s) in RCA: 224] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/04/2010] [Accepted: 05/07/2010] [Indexed: 01/05/2023]
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De Amici M, Dallanoce C, Holzgrabe U, Tränkle C, Mohr K. Allosteric ligands for G protein-coupled receptors: a novel strategy with attractive therapeutic opportunities. Med Res Rev 2010; 30:463-549. [PMID: 19557759 DOI: 10.1002/med.20166] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Allosteric receptor ligands bind to a recognition site that is distinct from the binding site of the endogenous messenger molecule. As a consequence, allosteric agents may attach to receptors that are already transmitter-bound. Ternary complex formation opens an avenue to qualitatively new drug actions at G protein-coupled receptors (GPCRs), in particular receptor subtype selective potentiation of endogenous transmitter action. Consequently, suitable exploitation of allosteric recognition sites as alternative molecular targets could pave the way to a drug discovery paradigm different from those aimed at mimicking or blocking the effects of endogenous (orthosteric) receptor activators. The number of allosteric ligands reported to modulate GPCR function is steadily increasing and some have already reached routine clinical use. This review aims at introducing into this fascinating field of drug discovery and at providing an overview about the achievements that have already been made. Various case examples will be discussed in the framework of GPCR classification (family A, B, and C receptors). In addition, the behavior at muscarinic receptors of hybrid derivatives incorporating both an allosteric and an orthosteric fragment in a common molecular skeleton will be illustrated.
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Affiliation(s)
- Marco De Amici
- Department of Pharmaceutical Sciences Pietro Pratesi, University of Milan, via Mangiagalli 25, 20133 Milano, Italy.
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71
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Abstract
Based on preclinical and clinical studies, the neuropeptide calcitonin gene-related peptide (CGRP) is proposed to play a central role in the underlying pathology of migraine. CGRP and its receptor are widely expressed in both the peripheral and central nervous systems by multiple cell types involved in the regulation of inflammatory and nociceptive responses. Peripheral release of CGRP from trigeminal nerve fibres within the dura and from the cell body of trigeminal ganglion neurons is likely to contribute to peripheral sensitization of trigeminal nociceptors. Similarly, the release of CGRP within the trigeminal nucleus caudalis can facilitate activation of nociceptive second-order neurons and glial cells. Thus, CGRP is involved in the development and maintenance of persistent pain, central sensitization and allodynia, events characteristic of migraine pathology. In contrast, CGRP release within the brain is likely to function in an anti-nociceptive capacity. Given the role of CGRP in migraine pathology, the potential of CGRP receptor antagonists in the treatment of migraine has been investigated. Towards this end, the non-peptide CGRP receptor antagonists olcegepant and telcagepant have been shown to be effective in the acute treatment of migraine. While telcagepant is being pursued as a frontline abortive migraine drug in a phase III clinical trial, an oral formulation of a novel CGRP receptor antagonist, BI 44370, is currently in phase II clinical trials. Encouragingly, data from clinical studies on these compounds have clearly demonstrated the potential therapeutic benefit of this class of drugs and support the future development of CGRP receptor antagonists to treat migraine and possibly other types of chronic pain.
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Affiliation(s)
- Paul L Durham
- Center for Biomedical and Life Sciences, Missouri State University, 524 North Boonville Avenue, Springfield, MO 65806, USA.
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72
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Chan KY, Edvinsson L, Eftekhari S, Kimblad PO, Kane SA, Lynch J, Hargreaves RJ, de Vries R, Garrelds IM, van den Bogaerdt AJ, Danser AHJ, Maassenvandenbrink A. Characterization of the calcitonin gene-related peptide receptor antagonist telcagepant (MK-0974) in human isolated coronary arteries. J Pharmacol Exp Ther 2010; 334:746-52. [PMID: 20573757 DOI: 10.1124/jpet.110.165993] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The sensory neuropeptide calcitonin gene-related peptide (CGRP) plays a role in primary headaches, and CGRP receptor antagonists are effective in migraine treatment. CGRP is a potent vasodilator, raising the possibility that antagonism of its receptor could have cardiovascular effects. We therefore investigated the effects of the antimigraine CGRP receptor antagonist telcagepant (MK-0974) [N-[(3R,6S)-6-(2,3-difluorophenyl)-2-oxo-1-(2,2,2-trifluoroethyl)azepan-3-yl]-4-(2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridine-1-yl)piperidine-1-carboxamide] on human isolated coronary arteries. Arteries with different internal diameters were studied to assess the potential for differential effects across the coronary vascular bed. The concentration-dependent relaxation responses to human alphaCGRP were greater in distal coronary arteries (i.d. 600-1000 microm; E(max) = 83 +/- 7%) than proximal coronary arteries (i.d. 2-3 mm; E(max) = 23 +/- 9%), coronary arteries from explanted hearts (i.d. 3-5 mm; E(max) = 11 +/- 3%), and coronary arterioles (i.d. 200-300 microm; E(max) = 15 +/- 7%). Telcagepant alone did not induce contraction or relaxation of these coronary blood vessels. Pretreatment with telcagepant (10 nM to 1 microM) antagonized alphaCGRP-induced relaxation competitively in distal coronary arteries (pA(2) = 8.43 +/- 0.24) and proximal coronary arteries and coronary arterioles (1 microM telcagepant, giving pK(B) = 7.89 +/- 0.13 and 7.78 +/- 0.16, respectively). alphaCGRP significantly increased cAMP levels in distal, but not proximal, coronary arteries, and this was abolished by pretreatment with telcagepant. Immunohistochemistry revealed the expression and colocalization of the CGRP receptor elements calcitonin-like receptor and receptor activity-modifying protein 1 in the smooth muscle cells in the media layer of human coronary arteries. These findings in vitro support the cardiovascular safety of CGRP receptor antagonists and suggest that telcagepant is unlikely to induce coronary side effects under normal cardiovascular conditions.
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Affiliation(s)
- K Y Chan
- Division of Pharmacology, Vascular, and Metabolic Diseases, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
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Sinclair SR, Kane SA, Van der Schueren BJ, Xiao A, Willson KJ, Boyle J, de Lepeleire I, Xu Y, Hickey L, Denney WS, Li CC, Palcza J, Vanmolkot FHM, Depré M, Van Hecken A, Murphy MG, Ho TW, de Hoon JN. Inhibition of capsaicin-induced increase in dermal blood flow by the oral CGRP receptor antagonist, telcagepant (MK-0974). Br J Clin Pharmacol 2010; 69:15-22. [PMID: 20078608 DOI: 10.1111/j.1365-2125.2009.03543.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT * Calcitonin gene-related peptide (CGRP) was first described as a potent vasodilator. * CGRP is also increasingly recognized as a key player in the pathophysiology of migraine, and CGRP receptor antagonists potentially offer a new approach for treating migraine. * A novel pharmacodynamic assay to measure CGRP receptor antagonist activity non-invasively in humans has been developed, which involves measuring the increase in dermal blood flow induced by topical application of capsaicin on the forearm. WHAT THIS STUDY ADDS * This study shows that the novel oral CGRP receptor antagonist, telcagepant, inhibits the increases in dermal blood flow induced by the topical application of capsaicin on the human forearm. * This experimental medicine model may have utility to assist in dose selection for the development of CGRP receptor antagonists. AIMS To evaluate inhibition of capsaicin-induced increase in dermal blood flow (DBF) following telcagepant (MK-0974), a potent and selective orally bioavailable calcitonin gene-related peptide (CGRP) receptor antagonist being developed for the acute treatment of migraine. METHODS A three-period crossover study in 12 healthy adult men. Each subject received a single oral dose of telcagepant 300 mg, telcagepant 800 mg or placebo at 0 h, followed 0.5 and 3.5 h later by two topical doses of 300 and 1000 microg capsaicin per 20 microl water-ethanol mixture. Capsaicin was applied at two sites on the volar surface of the subjects' left and right forearms. DBF was assessed by laser Doppler perfusion imaging immediately before ('baseline'), and 0.5 h after each capsaicin application at 1 and 4 h. Plasma samples to determine telcagepant concentrations were collected immediately after laser Doppler perfusion imaging. A pharmacodynamic model was developed to explore the relationship between plasma concentration and inhibition of capsaicin-induced increase in DBF. RESULTS Geometric mean plasma concentrations after dosing with 300 mg and 800 mg telcagepant were 720 and 1146 nm, respectively, at 1 h, vs. 582 and 2548 nm, respectively, at 4 h. The pharmacodynamic model suggested that the EC(90) for telcagepant inhibition of capsaicin-induced increases in DBF was 909 nm. CONCLUSIONS Telcagepant inhibits the increases in DBF induced by the topical application of capsaicin on the human forearm. This experimental medicine model may have utility to assist in dose selection for the development of CGRP receptor antagonists.
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74
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Bell IM, Gallicchio SN, Wood MR, Quigley AG, Stump CA, Zartman CB, Fay JF, Li CC, Lynch JJ, Moore EL, Mosser SD, Prueksaritanont T, Regan CP, Roller S, Salvatore CA, Kane SA, Vacca JP, Selnick HG. Discovery of MK-3207: A Highly Potent, Orally Bioavailable CGRP Receptor Antagonist. ACS Med Chem Lett 2010; 1:24-9. [PMID: 24900170 DOI: 10.1021/ml900016y] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 01/05/2010] [Indexed: 12/30/2022] Open
Abstract
Incorporation of polar functionality into a series of highly potent calcitonin gene-related peptide (CGRP) receptor antagonists was explored in an effort to improve pharmacokinetics. This strategy identified piperazinone analogues that possessed improved solubility at acidic pH and increased oral bioavailability in monkeys. Further optimization led to the discovery of the clinical candidate 2-[(8R)-8-(3,5-difluorophenyl)-10-oxo-6,9-diazaspiro[4.5]dec-9-yl]-N-[(2R)-2'-oxo-1,1',2',3-tetrahydrospiro[indene-2,3'-pyrrolo[2,3-b]pyridin]-5-yl]acetamide (MK-3207) (4), the most potent orally active CGRP receptor antagonist described to date.
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75
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Identification of potent, highly constrained CGRP receptor antagonists. Bioorg Med Chem Lett 2010; 20:2572-6. [DOI: 10.1016/j.bmcl.2010.02.086] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2010] [Revised: 02/19/2010] [Accepted: 02/22/2010] [Indexed: 11/20/2022]
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76
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Edvinsson L, Ho TW. CGRP receptor antagonism and migraine. Neurotherapeutics 2010; 7:164-75. [PMID: 20430315 PMCID: PMC5084097 DOI: 10.1016/j.nurt.2010.02.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 02/11/2010] [Indexed: 10/19/2022] Open
Abstract
Calcitonin gene-related peptide (CGRP) is expressed throughout the central and peripheral nervous systems, consistent with control of vasodilatation, nociception, motor function, secretion, and olfaction. alphaCGRP is prominently localized in primary spinal afferent C and ADelta fibers of sensory ganglia, and betaCGRP is the main isoform in the enteric nervous system. In the CNS there is a wide distribution of CGRP-containing neurons, with the highest levels occurring in striatum, amygdala, colliculi, and cerebellum. The peripheral projections are involved in neurogenic vasodilatation and inflammation, and central release induces hyperalgesia. CGRP is released from trigeminal nerves in migraine. Trigeminal nerve activation results in antidromic release of CGRP to cause non-endothelium-mediated vasodilatation. At the central synapses in the trigeminal nucleus caudalis, CGRP acts postjunctionally on second-order neurons to transmit pain signals centrally via the brainstem and midbrain to the thalamus and higher cortical pain regions. Recently developed CGRP receptor antagonists are effective at aborting acute migraine attacks. They may act both centrally and peripherally to attenuate signaling within the trigeminovascular pathway.
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Affiliation(s)
- Lars Edvinsson
- Department of Medicine, Institute of Clinical Sciences, Lund University Hospital, Lund University, 22185 Lund, Sweden.
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77
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Edvinsson L, Chan KY, Eftekhari S, Nilsson E, de Vries R, Säveland H, Dirven CMF, Danser AHJ, MaassenVanDenBrink A. Effect of the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant in human cranial arteries. Cephalalgia 2010; 30:1233-40. [DOI: 10.1177/0333102410362122] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction: Calcitonin gene-related peptide (CGRP) is a neuronal messenger in intracranial sensory nerves and is considered to play a significant role in migraine pathophysiology. Materials and methods: We investigated the effect of the CGRP receptor antagonist, telcagepant, on CGRP-induced cranial vasodilatation in human isolated cerebral and middle meningeal arteries. We also studied the expression of the CGRP receptor components in cranial arteries with immunocytochemistry. Concentration response curves to αCGRP were performed in human isolated cerebral and middle meningeal arteries in the absence or presence of telcagepant. Arterial slices were stained for RAMP1, CLR and actin in a double immunofluorescence staining. Results: In both arteries, we found that: (i) telcagepant was devoid of any contractile or relaxant effects per se; (ii) pretreatment with telcagepant antagonised the αCGRP-induced relaxation in a competitive manner; and (iii) immunohistochemistry revealed expression and co-localisation of CLR and RAMP1 in the smooth muscle cells in the media layer of both arteries. Conclusions: Our findings provide morphological and functional data on the presence of CGRP receptors in cerebral and meningeal arteries, which illustrates a possible site of action of telcagepant in the treatment of migraine.
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Affiliation(s)
- Lars Edvinsson
- Department of Internal Medicine Lund University Hospital, Lund, Sweden
| | - Kayi Y Chan
- Department of Internal Medicine Division of Pharmacology, Vascular and Metabolic Diseases, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Sajedeh Eftekhari
- Department of Internal Medicine Lund University Hospital, Lund, Sweden
| | - Elisabeth Nilsson
- Department of Internal Medicine Lund University Hospital, Lund, Sweden
| | - René de Vries
- Department of Internal Medicine Division of Pharmacology, Vascular and Metabolic Diseases, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Hans Säveland
- Department of Neurosurgery, Lund University Hospital, Lund, Sweden
| | - Clemens MF Dirven
- Department of Neurosurgery, Division of Pharmacology, Vascular and Metabolic Diseases, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - AH Jan Danser
- Department of Internal Medicine Division of Pharmacology, Vascular and Metabolic Diseases, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Antoinette MaassenVanDenBrink
- Department of Internal Medicine Division of Pharmacology, Vascular and Metabolic Diseases, Erasmus Medical Centre, Rotterdam, The Netherlands
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78
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Moore EL, Gingell JJ, Kane SA, Hay DL, Salvatore CA. Mapping the CGRP receptor ligand binding domain: tryptophan-84 of RAMP1 is critical for agonist and antagonist binding. Biochem Biophys Res Commun 2010; 394:141-5. [PMID: 20188075 DOI: 10.1016/j.bbrc.2010.02.131] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 02/19/2010] [Indexed: 11/17/2022]
Abstract
The calcitonin receptor-like receptor (CLR) associates with the accessory protein RAMP1 to form a receptor for the neuropeptide calcitonin gene-related peptide (CGRP). Multiple lines of evidence have implicated CGRP in the pathophysiology of migraine headache making the CGRP receptor an attractive target for development of small-molecule antagonists as a novel treatment for this debilitating condition. The CGRP receptor antagonists telcagepant and olcegepant (BIBN4096BS) have demonstrated clinical efficacy in the treatment of migraine and there is now a need to better understand how these molecules interact with the receptor. Previous work has shown the extracellular portion of RAMP1 to be important for binding of these antagonists, with tryptophan-74 being a key interaction site. The crystal structure of the extracellular portion of human RAMP1 placed tryptophan-74 in a hydrophobic patch hypothesized to interact with CGRP receptor ligands and also identified nearby residues that may be important for ligand binding. In this study we explored the role played by these residues of RAMP1 using an alanine replacement strategy. We confirmed a role for tryptophan-74 in antagonist binding and also identified arginine-67 as being important for binding of telcagepant but not compound 3, a close analog of BIBN4096BS. We also identified tryptophan-84 as being critical for both high-affinity binding of the non-peptide antagonists as well as the peptides CGRP and CGRP(8-37). These data for the first time pinpoint a specific RAMP1 residue important for both antagonist and agonist potency and are consistent with the N-terminal domain of RAMP1 forming the binding pocket interface with CLR.
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Affiliation(s)
- E L Moore
- Merck Research Laboratories, Department of Pain & Migraine Research, West Point, PA, USA.
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79
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Paone DV, Staas DD. Calcitonin gene-related peptide receptor antagonists for the treatment of migraine: a patent review. Expert Opin Ther Pat 2010; 19:1675-713. [PMID: 19939188 DOI: 10.1517/13543770903359822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Migraine is a debilitating headache disorder which affects approximately 12% of the general population and is the cause of significant loss of productivity (i.e., lost time from work or school) for those afflicted. The current standard of care, the 5-HT(1B/1D) agonists known as triptans, is contraindicated in patients with cardiovascular disease due to their inherent vasoconstrictive activity; thus, there is a need to develop an alternative therapy for the treatment of the disorder. OBJECTIVE This article reviews patent publications related to the use of small molecule calcitonin gene-related peptide (CGRP) receptor antagonists for the treatment of migraine that have appeared in the literature within the past decade. The commentary is supplemented by information presented in journal articles and focuses on the activity of several major pharmaceutical companies in the field. CONCLUSION Two small molecule CGRP receptor antagonists, olcegepant and telcagepant, have been shown to be clinically efficacious in the treatment of migraine, and thus provide validation of this novel therapeutic mechanism.
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Affiliation(s)
- Daniel V Paone
- Department of Medicinal Chemistry, Merck Research Laboratories, West Point, PA 19486, USA.
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80
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Salvatore CA, Moore EL, Calamari A, Cook JJ, Michener MS, O'Malley S, Miller PJ, Sur C, Williams DL, Zeng Z, Danziger A, Lynch JJ, Regan CP, Fay JF, Tang YS, Li CC, Pudvah NT, White RB, Bell IM, Gallicchio SN, Graham SL, Selnick HG, Vacca JP, Kane SA. Pharmacological properties of MK-3207, a potent and orally active calcitonin gene-related peptide receptor antagonist. J Pharmacol Exp Ther 2010; 333:152-60. [PMID: 20065019 DOI: 10.1124/jpet.109.163816] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Calcitonin gene-related peptide (CGRP) has long been hypothesized to play a key role in migraine pathophysiology, and the advent of small-molecule antagonists has clearly demonstrated a clinical link between blocking the CGRP receptor and migraine efficacy. 2-[(8R)-8-(3,5-Difluorophenyl)-10-oxo-6,9-diazaspiro[4.5]dec-9-yl]-N-[(2R)-2'-oxo-1,1',2',3-tetrahydrospiro[indene-2,3'-pyrrolo[2,3-b]pyridin]-5-yl]acetamide (MK-3207) represents the third CGRP receptor antagonist to display clinical efficacy in migraine trials. Here, we report the pharmacological characterization of MK-3207, a potent and orally bioavailable CGRP receptor antagonist. In vitro, MK-3207 is a potent antagonist of the human and rhesus monkey CGRP receptors (K(i) = 0.024 nM). In common with other CGRP receptor antagonists, MK-3207 displays lower affinity for CGRP receptors from other species, including canine and rodent. As a consequence of species selectivity, the in vivo potency was assessed in a rhesus monkey pharmacodynamic assay measuring capsaicin-induced changes in forearm dermal blood flow via laser Doppler imaging. MK-3207 produced a concentration-dependent inhibition of dermal vasodilation, with plasma concentrations of 0.8 and 7 nM required to block 50 and 90% of the blood flow increase, respectively. The tritiated analog [3H]MK-3207 was used to study the binding characteristics on the human CGRP receptor. [3H]MK-3207 displayed reversible and saturable binding (K(D) = 0.06 nM), and the off-rate was determined to be 0.012 min(-1), with a t(1/2) value of 59 min. In vitro autoradiography studies on rhesus monkey brain slices identified the highest level of binding in the cerebellum, brainstem, and meninges. Finally, as an index of central nervous system penetrability, the in vivo cerebrospinal fluid/plasma ratio was determined to be 2 to 3% in cisterna magna-ported rhesus monkeys.
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81
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Waeber C, Hargreaves R. Current and emerging therapies for migraine prevention and treatment. HANDBOOK OF CLINICAL NEUROLOGY 2010; 97:789-809. [PMID: 20816471 DOI: 10.1016/s0072-9752(10)97065-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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82
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Abstract
Headache treatment has been based primarily on experiences with non-specific drugs such as analgesics, non-steroidal anti-inflammatory drugs, or drugs that were originally developed to treat other diseases, such as beta-blockers and anticonvulsant medications. A better understanding of the basic pathophysiological mechanisms of migraine and other types of headache has led to the development over the past two decades of more target-specific drugs. Since activation of the trigeminovascular system and neurogenic inflammation are thought to play important roles in migraine pathophysiology, experimental studies modeling those events successfully predicted targets for selective development of pharmacological agents to treat migraine. Basically, there are two fundamental strategies for the treatment of migraine, abortive or preventive, based to a large degree on the frequency of attacks. The triptans, which exhibit potency towards selective serotonin (5-hydroxytryptamine, 5-HT) receptors expressed on trigeminal nerves, remain the most effective drugs for the abortive treatment of migraine. However, numerous preventive medications are currently available that modulate the excitability of the nervous system, particularly the cerebral cortex. In this chapter, the pharmacology of commercially available medications as well as drugs in development that prevent or abort headache attacks will be discussed.
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Affiliation(s)
- Hayrunnisa Bolay
- Department of Neurology, Gazi Hospital and Neuropsychiatry Centre, Gazi University, Besevler, Ankara, Turkey.
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83
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Villalón CM, Olesen J. The role of CGRP in the pathophysiology of migraine and efficacy of CGRP receptor antagonists as acute antimigraine drugs. Pharmacol Ther 2009; 124:309-23. [DOI: 10.1016/j.pharmthera.2009.09.003] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2009] [Accepted: 09/01/2009] [Indexed: 12/31/2022]
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84
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Poyner DR, Hay DL, Conner AC. CGRP receptor antagonists: design and screening. Expert Opin Drug Discov 2009; 4:1253-65. [DOI: 10.1517/17460440903413496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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85
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Miller PS, Barwell J, Poyner DR, Wigglesworth MJ, Garland SL, Donnelly D. Non-peptidic antagonists of the CGRP receptor, BIBN4096BS and MK-0974, interact with the calcitonin receptor-like receptor via methionine-42 and RAMP1 via tryptophan-74. Biochem Biophys Res Commun 2009; 391:437-42. [PMID: 19914210 PMCID: PMC2824848 DOI: 10.1016/j.bbrc.2009.11.076] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 11/10/2009] [Indexed: 10/27/2022]
Abstract
The receptor for calcitonin gene-related peptide (CGRP) has been the target for the development of novel small molecule antagonists for the treatment of migraine. Two such antagonists, BIBN4096BS and MK-0974, have shown great promise in clinical trials and hence a deeper understanding of the mechanism of their interaction with the receptor is now required. The structure of the CGRP receptor is unusual since it is comprised of a hetero-oligomeric complex between the calcitonin receptor-like receptor (CRL) and an accessory protein (RAMP1). Both the CLR and RAMP1 components have extracellular domains which interact with each other and together form part of the peptide-binding site. It seems likely that the antagonist binding site will also be located on the extracellular domains and indeed Trp-74 of RAMP1 has been shown to form part of the binding site for BIBN4096BS. However, despite a chimeric study demonstrating the role of the N-terminal domain of CLR in antagonist binding, no specific residues have been identified. Here we carry out a mutagenic screen of the extreme N-terminal domain of CLR (residues 23-63) and identify a mutant, Met-42-Ala, which displays 48-fold lower affinity for BIBN4096BS and almost 900-fold lower affinity for MK-0974. In addition, we confirm that the Trp-74-Lys mutation at human RAMP1 reduces BIBN4096BS affinity by over 300-fold and show for the first time a similar effect for MK-0974 affinity. The data suggest that the non-peptide antagonists occupy a binding site close to the interface of the N-terminal domains of CLR and RAMP1.
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Affiliation(s)
- Philip S Miller
- Institute of Membrane & Systems Biology, LIGHT Laboratories, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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86
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87
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Burgey CS, Potteiger CM, Deng JZ, Mosser SD, Salvatore CA, Yu S, Roller S, Kane SA, Vacca JP, Williams TM. Optimization of azepanone calcitonin gene-related peptide (CGRP) receptor antagonists: Development of novel spiropiperidines. Bioorg Med Chem Lett 2009; 19:6368-72. [DOI: 10.1016/j.bmcl.2009.09.066] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 09/16/2009] [Accepted: 09/17/2009] [Indexed: 10/20/2022]
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88
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Calcitonin, amylin, CGRP and adrenomedullin. Br J Pharmacol 2009. [DOI: 10.1111/j.1476-5381.2009.00501_16.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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89
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Farinelli I, De Filippis S, Coloprisco G, Missori S, Martelletti P. Future drugs for migraine. Intern Emerg Med 2009; 4:367-73. [PMID: 19551474 DOI: 10.1007/s11739-009-0273-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Accepted: 06/01/2009] [Indexed: 11/30/2022]
Abstract
Migraine is a complex, neurovascular disorder in which genetic and environmental factors interact. At present, frontline therapies in the acute treatment of migraine include the use of non-steroidal anti-inflammatory drugs and triptans. Evidence indicates that calcitonin gene-related peptide (CGRP) plays a fundamental role in the mechanism of migraine. CGRP is a strong vasodilatatory neuropeptide that is released from activated trigeminal sensory nerves. The development of CGRP antagonists has also been driven by the fact that triptans are vasoconstrictive and cannot be safely used in patients with cardiovascular risk factors. Olcegepant (BIBN4096) is the first CGRP antagonist for the treatment of migraine that has been tested in clinical trials, but because of its poor oral bioavailability, only the intravenous formulation has been tested. The first oral non-peptide CGRP antagonist, telcagepant, has been shown recently to be highly effective in the treatment of migraine attacks. This development can be considered as the most important pharmacological breakthrough for migraine treatment since the introduction of sumatriptan in the early 1990s. These results are also of importance, since they support an interesting pathophysiological hypothesis of migraine. The pipeline of future compounds for the treatment of acute migraine headaches include TPRV1 antagonists, prostaglandin E receptor 4 (EP(4)) receptor antagonists, serotonin 5HT1(F) receptor agonists and nitric oxide synthase inhibitors. The immediate future of a preventative treatment for migraine headaches is well represented by botulinum toxin type-A, glutamate NMDA receptor antagonists, gap-junction blocker tonabersat and an angiotensin type 1 blocker candesartan.
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Affiliation(s)
- Ivano Farinelli
- Department of Medical and Molecular Sciences, Regional Referral Headache Centre, II School of Medicine, Sapienza University of Rome, Sant'Andrea Hospital, Via di Grottarossa 1039, 00189 Rome, Italy
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90
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Chizh BA, Sang CN. Use of sensory methods for detecting target engagement in clinical trials of new analgesics. Neurotherapeutics 2009; 6:749-54. [PMID: 19789077 PMCID: PMC5084294 DOI: 10.1016/j.nurt.2009.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The translation of analgesic efficacy seen in preclinical pain models into the clinic is problematic and is associated with a number of factors that may result in the failure of clinical trials to detect the effect of investigational therapeutic agents. The use of translational pain biomarkers in phase I trials can potentially reduce some of these risks by measuring the interaction between the drug and its target (termed target engagement) in humans. To serve this purpose, sensory tests and other measures of pharmacological activity in nociceptive pathways need to be identified, based on the preclinical profile of the drug being tested and the feasibility of human assessments. Here we discuss some examples to assess the utility of sensory and related pain biomarkers in the early phase of evaluation of novel analgesics for confirmation of target engagement in humans. The emphasis is on the TRPV1 antagonists, but some other target mechanisms are also discussed in examining the validity of this approach.
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Affiliation(s)
- Boris A Chizh
- GlaxoSmithKline, Addenbrooke's Centre for Clinical Investigation, Addenbrooke's Hospital, Cambridge CB2 2GG, United Kingdom.
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91
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Sixt ML, Messlinger K, Fischer MJM. Calcitonin gene-related peptide receptor antagonist olcegepant acts in the spinal trigeminal nucleus. Brain 2009; 132:3134-41. [DOI: 10.1093/brain/awp168] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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92
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Bell IM, Bednar RA, Corcoran HA, Fay JF, Gallicchio SN, Johnston VK, Hershey JC, Miller-Stein CM, Moore EL, Mosser SD, Roller SA, Salvatore CA, Theberge CR, Wong BK, Blair Zartman C, Kane SA, Williams TM, Graham SL, Vacca JP. The identification of potent, orally bioavailable tricyclic CGRP receptor antagonists. Bioorg Med Chem Lett 2009; 19:4740-2. [DOI: 10.1016/j.bmcl.2009.06.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 06/10/2009] [Accepted: 06/15/2009] [Indexed: 11/25/2022]
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93
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Abstract
Migraine is a complex neurological disorder that in recent years has received more and more attention. Knowledge regarding this primary headache has increased substantially, both with respect to its pathogenesis and how to effectively treat its symptoms. Over the years, the proposed location of the onset of migraine has moved from the periphery of the nervous system toward deeper parts of the brain. Migraine can be viewed as an inherited failure of trigeminal sensory processing with abnormal neuronal excitability in the trigeminal nucleus caudalis, which, in turn, causes central sensitization and amplification of the pain. Increased activation of the trigeminal nerve during a migraine attack causes release of the calcitonin gene-related peptide (CGRP) inside and outside the BBB. Within the CNS, CGRP promotes trigeminal sensory input and facilitates central sensitization. The future introduction of CGRP antagonists in clinical practice could represent significant progress for acute migraine therapy.
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Affiliation(s)
- Carl Dahlöf
- Professor of Neurology, Institute of Neuroscience & Physiology, Sahlgrenska University Hospital, Medical Director & Founder of Gothenburg Migraine Clinic, Gothenburg Migraine Clinic, c/o Läkarhuset, Södra vägen 27, S-411 35 Gothenburg, Sweden
| | - Hans-Christoph Diener
- Professor of Neurology, Department of Neurology, University Duisburg-Essen, Essen, Germany
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94
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95
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Current World Literature. Curr Opin Neurol 2009; 22:321-9. [DOI: 10.1097/wco.0b013e32832cf9cb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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96
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Tepper SJ, Stillman MJ. Clinical and preclinical rationale for CGRP-receptor antagonists in the treatment of migraine. Headache 2009; 48:1259-68. [PMID: 18808506 DOI: 10.1111/j.1526-4610.2008.01214.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Calcitonin gene-related peptide (CGRP) is linked to migraine and other primary headache disorders. It is found in every location described in migraine genesis and processing, including meninges, trigeminal ganglion, trigeminocervical complex, brainstem nuclei, and cortex. It is released in animal models following stimulation of the CNS similar to that seen in migraine, and triptans inhibit this release. Injection of CGRP into migraineurs results in delayed headache similar to migraine. Elevation of CGRP occurs during migraine, resolving following migraine-specific treatment. Finally, and most importantly, CGRP receptor antagonists terminate migraine with efficacy similar to triptans. Both intravenous olcegepant (BIBN 4096 BS) and oral telcagepant (MK-0974) have been effective, safe, and well tolerated in phase I and II studies. Telcagepant is currently in phase III trials, and preliminary results are favorable. The potential for a migraine-specific medication without vasoconstrictive or vascular side effects is enormous. CGRP receptor blockade may also have applications in other pathologic and pain syndromes.
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Affiliation(s)
- Stewart J Tepper
- Center for Headache and Pain, Department of Neurology, Neurological Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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Durham PL. Inhibition of calcitonin gene-related peptide function: a promising strategy for treating migraine. Headache 2009; 48:1269-75. [PMID: 18808507 DOI: 10.1111/j.1526-4610.2008.01215.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The neuropeptide calcitonin gene-related peptide (CGRP) is implicated in the underlying pathology of migraine. Serum levels of CGRP, which are elevated during a migraine attack, have been reported to return to normal with alleviation of pain. In addition, CGRP administration has been shown to cause a migraine-like headache in susceptible individuals. Importantly, CGRP receptors are found on many cell types within the trigeminovascular system that are thought to play important roles in controlling inflammatory and nociceptive processes. Based on these findings, it was proposed that blockage of CGRP receptor function and, hence, the physiological effects of CGRP would be effective in aborting a migraine attack. This review will summarize key preclinical data that support the therapeutic potential of using CGRP receptor antagonists or molecules that bind CGRP within the context of current neurovascular theories on migraine pathology.
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Affiliation(s)
- Paul L Durham
- Department of Biology, Missouri State University, Springfield, MO 65897, USA
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98
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Molecular investigations of BKCa channels and the modulatory β-subunits in porcine basilar and middle cerebral arteries. J Mol Histol 2009; 40:87-97. [DOI: 10.1007/s10735-009-9216-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Accepted: 03/13/2009] [Indexed: 12/29/2022]
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99
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Chizh BA, Priestley T, Rowbotham M, Schaffler K. Predicting therapeutic efficacy — Experimental pain in human subjects. ACTA ACUST UNITED AC 2009; 60:243-54. [DOI: 10.1016/j.brainresrev.2008.12.016] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2008] [Indexed: 02/05/2023]
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100
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Hargreaves RJ, Lines CR, Rapoport AM, Ho TW, Sheftell FD. Ten years of rizatriptan: from development to clinical science and future directions. Headache 2009; 49 Suppl 1:S3-20. [PMID: 19161563 DOI: 10.1111/j.1526-4610.2008.01335.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The year 2008 marked the 10th anniversary since rizatriptan was first launched for the acute treatment of migraine. In this article we discuss the concepts that motivated the preclinical and clinical development of rizatriptan, the clinical evidence that has driven its use over the past decade, rizatriptan's overall contribution to the field, and future directions for research.
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