Regulatory Strategies for Promoting the Safe Use of Prescription Opioids and the Potential Impact of Overregulation

Total Page:16

File Type:pdf, Size:1020Kb

Regulatory Strategies for Promoting the Safe Use of Prescription Opioids and the Potential Impact of Overregulation REGULATORY STRATEGIES FOR PROMOTING THE SAFE USE OF PRESCRIPTION OPIOIDS AND THE POTENTIAL IMPACT OF OVERREGULATION Wissenschaftliche Prüfungsarbeit zur Erlangung des Titels „Master of Drug Regulatory Affairs“ der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn vorgelegt von Dr. Katja Bendrin aus Torgau Bonn 2020 Betreuer und Erster Referent: Dr. Birka Lehmann Zweiter Referent: Dr. Jan Heun REGULATORY STRATEGIES FOR PROMOTING THE SAFE USE OF PRESCRIPTION OPIOIDS AND THE POTENTIAL IMPACT OF OVERREGULATION Acknowledgment │ page II of VII Acknowledgment I want to thank Dr. Birka Lehmann for her willingness to supervise this work and for her support. I further thank Dr. Jan Heun for assuming the role of the second reviewer. A big thank you to the DGRA Team for the organization of the master's course and especially to Dr. Jasmin Fahnenstich for her support to find the thesis topic and supervisors. Furthermore, thank you Harald for your patient support. REGULATORY STRATEGIES FOR PROMOTING THE SAFE USE OF PRESCRIPTION OPIOIDS AND THE POTENTIAL IMPACT OF OVERREGULATION Table of Contents │ page III of VII Table of Contents 1. Scope.................................................................................................................................... 1 2. Introduction ......................................................................................................................... 2 2.1 Classification of Opioid Medicines .................................................................................................. 2 2.2 Opioid Receptors and Mode of Action ........................................................................................... 3 2.3 Need for Opioid Medicines ............................................................................................................. 4 2.3.1 WHO Analgesic Ladder ............................................................................................................... 5 2.3.2 WHO Essential Medicines List .................................................................................................... 6 2.3.3 Adverse Events of Opioid Medicines .......................................................................................... 6 2.4 Consequences of Unmanaged Pain ................................................................................................ 8 3. International Control and Availability of Opioid Medicines for Pain Management................... 9 3.1 International Control by Drug Control Treaties .............................................................................. 9 3.2 Availability of Opioids for Treatment ........................................................................................... 10 3.3 The Prevalence of Opioid-Related Harms Increases Worldwide .................................................. 12 4. Regulatory Barriers to Opioid Accessibility ........................................................................... 13 4.1 Europe .......................................................................................................................................... 16 4.1.1 Germany ................................................................................................................................... 16 4.1.2 United Kingdom ........................................................................................................................ 20 4.1.3 Poland ....................................................................................................................................... 24 4.2 North America .............................................................................................................................. 26 4.2.1 Canada ...................................................................................................................................... 27 4.3 Oceania ......................................................................................................................................... 31 4.3.1 Australia .................................................................................................................................... 31 4.4 Asia ............................................................................................................................................... 36 4.4.1 Japan ......................................................................................................................................... 37 4.4.2 India .......................................................................................................................................... 40 4.5 Africa ............................................................................................................................................. 44 4.5.1 South Africa .............................................................................................................................. 44 4.5.2 Rwanda ..................................................................................................................................... 47 5. Alternatives to Opioids, Novel Approaches, and their Regulatory Status............................... 54 5.1 Cannabis as Opioid Substitute ...................................................................................................... 54 5.2 Novel Non-opioids ........................................................................................................................ 54 5.3 Gene Therapy ............................................................................................................................... 55 6. Discussion and Conclusion ................................................................................................... 56 6.1 Implementation of the UN Single Convention 1961 into National Legislations ........................... 56 6.2 Availability of Clinical Guidelines for the Use of Opioids in Pain Management ........................... 59 6.3 Are Prescription Opioids the Drivers of Opioid Crises? ................................................................ 61 6.4 Addressing the Problematic Availability and Use of Opioids through Regulatory Measures ...... 62 7. Summary ............................................................................................................................ 64 8. References .......................................................................................................................... 66 9. Appendices ......................................................................................................................... 77 REGULATORY STRATEGIES FOR PROMOTING THE SAFE USE OF PRESCRIPTION OPIOIDS AND THE POTENTIAL IMPACT OF OVERREGULATION List of Tables │ page IV of VII List of Tables Table 1: Classification of Opioids............................................................................................................. 3 Table 2: Average Consumption of Narcotic Drugs in the Selected Countries, 2006-2008 and 2016-2018 ............................................................................................................................................................... 15 Table 3: Comparison of the National Control Acts for the Regulation of Opioids in Germany, UK, Poland, Canada, Australia, India, Japan, South Africa and Rwanda ................................................................... 50 List of Figures Figure 1: The WHO Cancer Pain Ladder for Adults ................................................................................. 5 Figure 2: Availability of Opioids for Pain Management ......................................................................... 12 REGULATORY STRATEGIES FOR PROMOTING THE SAFE USE OF PRESCRIPTION OPIOIDS AND THE POTENTIAL IMPACT OF OVERREGULATION List of Abbreviations │ page V of VII List of Abbreviations ACDA Act on Counteracting Drug Addiction art Article ARTG Australian Register of Therapeutic Goods ATC Anatomical Therapeutic Chemical AWMF Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften e.V.) BfArM Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel) BMG Federal Ministry of Health (Bundesministerium für Gesundheit) BtM Narcotics (Betäubungsmittel) BtMG German Narcotic Drugs Act (Betäubungsmittelgesetz) BtMVV Narcotic Drugs Prescription Ordinance (Betäubungsmittelverschreibungsverordnung) CBD Cannabidiol CBN Central Bureau of Narcotics CDC Centers for Disease Control and Prevention CDSA Controlled Drugs and Substances Act CDSCO Central Drugs Standard Control Organisation CHM Commission on Human Medicines CIOMS Council for International Organizations of Medical Sciences CNCP Chronic non-cancer pain CND Commission on Narcotic Drugs CNS Central nervous system CP Caudate putamen DDD Defined daily dose (The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults) DOP Delta (δ) OPiate receptor e.g. For example (lat. "exempli grazia") EML Essential Medicines List EWG Expert Working Group FDA Food and Drug Administration GABA Gamma-aminobutyric acid GPM Good Pain Management HIV Human immunodeficiency virus HPRG Health Products Regulation Group REGULATORY STRATEGIES FOR PROMOTING THE SAFE USE OF PRESCRIPTION OPIOIDS AND THE POTENTIAL IMPACT OF OVERREGULATION List of Abbreviations │ page VI of VII HRH Human resources for health IASP Association for the Study
Recommended publications
  • Illegal Drugs in Canada: Refocusing Canada’S Drug Strategy
    Illegal Drugs in Canada: Refocusing Canada’s Drug Strategy Major Research Paper By: Nicole Barrafato Ottawa University 1 May 2013 Introduction “Billions of dollars have gone into the anti-drug war and it has brought only huge criminal organizations. When you have poured in money for a century surely it is time for you to decide it is not working.” Dr E.K. Rodrigo, former Drug Tsar of Sri Lanka 2005 In the last decade international attitudes towards the prohibition of illegal drugs have undergone rapid change. For over half a century governments around the world have been fighting a declared “war on drugs.” Within the last two decades, however, most have conceded that this crusade has been an unmitigated failure. Even though most of the international community has acknowledged this failure, it has been slow to re-conceptualize how it views illegal drugs and explore alternative policies. Part I of this paper demonstrates that the rapid globalization of the past three decades has had a significant impact on the scope, speed and scale of deviant globalization, where illicit industries operate in the shadows of the legitimate global economy. It was also around this time that the American-led “war on drugs” was launched, which essentially shaped the international drug control regime. Part II addresses the failures of the current prohibition regime and outlines alternative policy approaches that could instead be taken to address the problem of illicit drugs. In addition, case studies on countries that have been at the forefront of innovative drug policies, namely the Netherlands, Portugal and Australia, will also be examined.
    [Show full text]
  • Peripheral Kappa Opioid Receptor Activation Drives Cold Hypersensitivity in Mice
    bioRxiv preprint doi: https://doi.org/10.1101/2020.10.04.325118; this version posted October 4, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Peripheral kappa opioid receptor activation drives cold hypersensitivity in mice Manish K. Madasu1,2,3, Loc V. Thang1,2,3, Priyanka Chilukuri1,3, Sree Palanisamy1,2, Joel S. Arackal1,2, Tayler D. Sheahan3,4, Audra M. Foshage3, Richard A. Houghten6, Jay P. McLaughlin5.6, Jordan G. McCall1,2,3, Ream Al-Hasani1,2,3 1Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University School of Medicine, St. Louis, MO, USA. 2Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, St. Louis, MO, USA 3Department of Anesthesiology, Pain Center, Washington University. St. Louis, MO, USA. 4 Division of Biology and Biomedical Science, Washington University in St. Louis, MO, USA 5Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA 6Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL, USA Corresponding Author: Dr. Ream Al-Hasani Center for Clinical Pharmacology St. Louis College of Pharmacy Washington University School of Medicine 660 South Euclid Campus Box 8054 St. Louis MO, 63110 [email protected] bioRxiv preprint doi: https://doi.org/10.1101/2020.10.04.325118; this version posted October 4, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
    [Show full text]
  • Analytical Performance of an Immunoassay to Measure Proenkephalin ⁎ Leslie J
    Clinical Biochemistry xxx (xxxx) xxx–xxx Contents lists available at ScienceDirect Clinical Biochemistry journal homepage: www.elsevier.com/locate/clinbiochem Analytical performance of an immunoassay to measure proenkephalin ⁎ Leslie J. Donatoa, ,Jeffrey W. Meeusena, John C. Lieskea, Deborah Bergmannc, Andrea Sparwaßerc, Allan S. Jaffea,b a Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, United States b Division of Cardiology, Mayo Clinic, Rochester, MN 55905, United States c Sphingotec GmbH, Hennigsdorf, Germany ARTICLE INFO ABSTRACT Keywords: Background: Endogenous opioids, enkephalins, are known to increase with acute kidney injury. Since the mature Biomarkers pentapeptides are unstable, we evaluated the performance of an assay that measures proenkephalin 119–159 Proenkephalin (PENK), a stable peptide formed concomitantly with mature enkephalins. Enkephalin Methods: PENK assay performance was evaluated on two microtiterplate/chemiluminescence sandwich im- Pro-enkephalin munoassay formats that required 18 or 1 h incubation times. PENK concentration was measured in plasma from penKid healthy individuals to establish a reference interval and in patients with varied levels of kidney function and Assay validation comorbidities to assess the association with measured glomerular filtration rate (mGFR) using iothalamate clearance. Results: Assay performance characteristics in plasma were similar between the assay formats. Limit of quanti- tation was 26.0 pmol/L (CV = 20%) for the 1 h assay and 17.3 pmol/L (CV = 3%) for the 18 h assay. Measurable ranges were 26–1540 pmol/L (1 h assay) and 18–2300 pmol/L (18 h assay). PENK concentrations are stable in plasma stored ambient to 10 days, refrigerated to at least 15 days, and frozen to at least 90 days.
    [Show full text]
  • House Bill No. 325
    FIRST REGULAR SESSION HOUSE BILL NO. 325 101ST GENERAL ASSEMBLY INTRODUCED BY REPRESENTATIVE PRICE IV. 0249H.01I DANA RADEMAN MILLER, Chief Clerk AN ACT To repeal sections 195.010, 579.015, 579.020, 579.040, 579.055, and 579.105, RSMo, and to enact in lieu thereof twenty new sections relating to the legalization of marijuana for adult use, with penalty provisions. Be it enacted by the General Assembly of the state of Missouri, as follows: Section A. Sections 195.010, 579.015, 579.020, 579.040, 579.055, and 579.105, RSMo, 2 are repealed and twenty new sections enacted in lieu thereof, to be known as sections 195.010, 3 195.2300, 195.2303, 195.2309, 195.2310, 195.2312, 195.2315, 195.2317, 195.2318, 195.2321, 4 195.2324, 195.2327, 195.2330, 195.2333, 579.015, 579.020, 579.040, 579.055, 579.105, and 5 610.134, to read as follows: 195.010. The following words and phrases as used in this chapter and chapter 579, 2 unless the context otherwise requires, mean: 3 (1) "Acute pain", pain, whether resulting from disease, accidental or intentional trauma, 4 or other causes, that the practitioner reasonably expects to last only a short period of time. Acute 5 pain shall not include chronic pain, pain being treated as part of cancer care, hospice or other 6 end-of-life care, or medication-assisted treatment for substance use disorders; 7 (2) "Addict", a person who habitually uses one or more controlled substances to such an 8 extent as to create a tolerance for such drugs, and who does not have a medical need for such 9 drugs, or who is so far addicted to the use of such drugs as to have lost the power of self-control 10 with reference to his or her addiction; 11 (3) "Administer", to apply a controlled substance, whether by injection, inhalation, 12 ingestion, or any other means, directly to the body of a patient or research subject by: 13 (a) A practitioner (or, in his or her presence, by his or her authorized agent); or EXPLANATION — Matter enclosed in bold-faced brackets [thus] in the above bill is not enacted and is intended to be omitted from the law.
    [Show full text]
  • Summary Analgesics Dec2019
    Status as of December 31, 2019 UPDATE STATUS: N = New, A = Advanced, C = Changed, S = Same (No Change), D = Discontinued Update Emerging treatments for acute and chronic pain Development Status, Route, Contact information Status Agent Description / Mechanism of Opioid Function / Target Indication / Other Comments Sponsor / Originator Status Route URL Action (Y/No) 2019 UPDATES / CONTINUING PRODUCTS FROM 2018 Small molecule, inhibition of 1% diacerein TWi Biotechnology / caspase-1, block activation of 1 (AC-203 / caspase-1 inhibitor Inherited Epidermolysis Bullosa Castle Creek Phase 2 No Topical www.twibiotech.com NLRP3 inflamasomes; reduced CCP-020) Pharmaceuticals IL-1beta and IL-18 Small molecule; topical NSAID Frontier 2 AB001 NSAID formulation (nondisclosed active Chronic low back pain Phase 2 No Topical www.frontierbiotech.com/en/products/1.html Biotechnologies ingredient) Small molecule; oral uricosuric / anti-inflammatory agent + febuxostat (xanthine oxidase Gout in patients taking urate- Uricosuric + 3 AC-201 CR inhibitor); inhibition of NLRP3 lowering therapy; Gout; TWi Biotechnology Phase 2 No Oral www.twibiotech.com/rAndD_11 xanthine oxidase inflammasome assembly, reduced Epidermolysis Bullosa Simplex (EBS) production of caspase-1 and cytokine IL-1Beta www.arraybiopharma.com/our-science/our-pipeline AK-1830 Small molecule; tropomyosin Array BioPharma / 4 TrkA Pain, inflammation Phase 1 No Oral www.asahi- A (ARRY-954) receptor kinase A (TrkA) inhibitor Asahi Kasei Pharma kasei.co.jp/asahi/en/news/2016/e160401_2.html www.neurosmedical.com/clinical-research;
    [Show full text]
  • “Biosynthesis of Morphine in Mammals”
    “Biosynthesis of Morphine in Mammals” D i s s e r t a t i o n zur Erlangung des akademischen Grades Doctor rerum naturalium (Dr. rer. nat.) vorgelegt der Naturwissenschaftlichen Fakultät I Biowissenschaften der Martin-Luther-Universität Halle-Wittenberg von Frau Nadja Grobe geb. am 21.08.1981 in Querfurt Gutachter /in 1. 2. 3. Halle (Saale), Table of Contents I INTRODUCTION ........................................................................................................1 II MATERIAL & METHODS ........................................................................................ 10 1 Animal Tissue ....................................................................................................... 10 2 Chemicals and Enzymes ....................................................................................... 10 3 Bacteria and Vectors ............................................................................................ 10 4 Instruments ........................................................................................................... 11 5 Synthesis ................................................................................................................ 12 5.1 Preparation of DOPAL from Epinephrine (according to DUNCAN 1975) ................. 12 5.2 Synthesis of (R)-Norlaudanosoline*HBr ................................................................. 12 5.3 Synthesis of [7D]-Salutaridinol and [7D]-epi-Salutaridinol ..................................... 13 6 Application Experiments .....................................................................................
    [Show full text]
  • Atopic Dermatitis - Ph 2 Trial Expected to Initiate Around Mid-Year 2019
    Targeting Pruritus With Novel Peripherally-Restricted Kappa Agonist Therapeutics Jefferies Healthcare Conference June, 2019 Forward Looking Statements This presentation contains certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward-looking statements by the words “anticipate,” “believe,” “continue,” “estimate,” “expect,” “objective,” “ongoing,” “plan,” “propose,” “potential,” “projected”, or “up-coming” and/or the negative of these terms, or other comparable terminology intended to identify statements about the future. Examples of these forward-looking statements in this presentation include, among other things, statements concerning plans, strategies and expectations for the future, including statements regarding the expected timing of our planned clinical trials; the potential results of ongoing and planned clinical trials; future regulatory and development milestones for the Company's product candidates; the size of the potential markets that are potentially addressable for the Company’s product candidates, including the postoperative and chronic pain markets, and the pruritus market; the potential commercialization of Korsuva™ in the licensed territories; the potential benefits of license agreements entered by the Company, including the potential milestone and royalty payments payable to Cara; and the Company's expected cash reach. These statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. Although we believe that we have a reasonable basis for each forward-looking statement contained in this presentation, we caution you that these statements are based on a combination of facts and factors currently known by us and our expectations of the future, about which we cannot be certain.
    [Show full text]
  • ABSTRACT CHAMBERS, CHERYL. Institutional
    ABSTRACT CHAMBERS, CHERYL. Institutional Racism: Is Law Used as a Tool to Perpetuate Racial Inequality? (Under the direction of Richard Della Fave.) Law is a mechanism we use to instigate social change and bring about equality. It is also the tool that has been used to institutionalize, legitimize and perpetuate inequality. In the past beliefs of racial inferiority and savagery may have resulted in legislation designed to perpetuate a group’s subordinate status. Laws and public policy are created within an historical and political context. Is there a connection between social climate and the advent of federal drug legislation? In this research, conflict and racial inequality perspectives are applied to the role of the economy and politics to foster understanding of opium laws in the late 1800’s and early 1900’s, the Marihuana Tax Act of 1937, and the Anti-Drug Abuse Act of 1986 and the contexts from which they emerged. It is hypothesized that an historical analysis of the Congressional discussions surrounding these drug laws will illustrate that competition and threat, economic and/or political, were present prior to the enactment of the laws. Analyses indicate that while economic and to a limited extent political competition between Chinese immigrants and white Americans affected the passage of the opium laws, economic and political competition had little effect on the passage of the Marihuana Tax Act or the Anti-Drug Abuse Act. While vilification of and anti-minority sentiment during the opium legislation was clear and recognizable, it was almost non-existent during the marijuana legislation, and present in only nuances in the 1980’s.
    [Show full text]
  • Modulation of the Mu and Kappa Opioid Axis for Treatment of Chronic Pruritus
    Modulation of the Mu and Kappa Opioid Axis for the Treatment of Chronic Pruritus Sarina Elmariah, MD, PhD1, Sarah Chisolm, MD2, Thomas Sciascia, MD3, Shawn G. Kwatra, MD4 1Massachusetts General Hospital, Boston, MA, USA; 2Emory University Department of Dermatology, Atlanta, GA, USA; VA VISN 7, USA; 3Trevi Therapeutics, New Haven, CT, USA; 4Johns Hopkins University School of Medicine, Baltimore, MD, USA Introduction Results Conclusions • Conditions such as uremic pruritus (UP) and prurigo nodularis • In the United States, opioid receptor–targeting agents have been used off-label to Figure 4. Change in VAS Scores From Baseline (Preobservation Period) to Last 7 – In a patient subgroup with severe UP (n=179), sleep disruption attributed to • These data suggest that agents that modulate underlying are characterized by chronic pruritus, which negatively impacts treat chronic itch19 Days of Treatment With KOR Agonist Nalfurafine vs Placebo for Uremic Pruritus21 itching improved significantly vs placebo (P=0.006) neurologic components of pruritus through µ-antagonism quality of life (QoL), sleep, and mood1-7 and/or κ-agonism are effective and safe options for the • Several agents that target MORs and KORs are being used off-label or are in clinical alfurafine 2.5 µg alfurafine 5 µg Placeo – The most common reason for discontinuing treatment was gastrointestinal side n112 n114 n111 treatment of chronic pruritus • Opioid receptors and their endogenous ligands are involved in development for the treatment of chronic itch associated with various disease states 0 effects (eg, nausea, vomiting) during titration the regulation of itch, with activation of mu (µ) opioid receptors (Figure 2) These agents have low abuse potential and generally appear well Figure 5.
    [Show full text]
  • CICAD/Doc.2147/14 Guatemala 18 November 2014 Original: English
    INTER-AMERICAN DRUG ABUSE CONTROL COMMISSION C I C A D Secretariat for Multidimensional Security FIFTY-SIXTH REGULAR SESSION OEA/Ser.L/XIV.2.56 November 19 - 21, 2014 CICAD/doc.2147/14 Guatemala 18 November 2014 Original: English THE REFORM OF CANNABIS LAWS IN JAMAICA MAURICE BAILEY, JAMAICA The Reform of Cannabis Laws in Jamaica The Jamaican Context • Cannabis Sativa (marijuana) is known as “ganja” in Jamaica. • Ganja was bought to Jamaica in the mid 19th century by imported labourers from India • Ganja use is widespread in Jamaica for recreational, religious and medicinal purposes. Brief History of Ganja Laws In Jamaica • Hague Convention 1912-contracting parties make possession of opium, morphine and cocaine a criminal offence. • Cannabis was not included in Convention • Jamaican Legislators passed Opium Law 1913 and included cannabis “ganja” • Issues of race and class prejudice The Dangerous Drugs Act 1948 • Prohibition of ganja now contained in the Dangerous Drugs Act. Passed in 1948 and amended several times since then • Absolute prohibition of any dealing with the ganja plant • Penalties were severe: between 1941 and 1972 a sentence of imprisonment of up to a maximum of 18 months was mandatory on conviction for possession • Section 2 defines “ganja” as follows; "ganja" includes all parts of the plant known as cannabis sativa from which the resin has not been extracted and includes any resin obtained from that plant, but does not include medicinal preparations made from that plant • Part IIIA (Sections 7A-7D) contain specific provisions for Ganja • Section 7A prohibits import or export or taking any steps preparatory to export.
    [Show full text]
  • Screening of 109 Neuropeptides on Asics Reveals No Direct Agonists
    www.nature.com/scientificreports OPEN Screening of 109 neuropeptides on ASICs reveals no direct agonists and dynorphin A, YFMRFamide and Received: 7 August 2018 Accepted: 14 November 2018 endomorphin-1 as modulators Published: xx xx xxxx Anna Vyvers, Axel Schmidt, Dominik Wiemuth & Stefan Gründer Acid-sensing ion channels (ASICs) belong to the DEG/ENaC gene family. While ASIC1a, ASIC1b and ASIC3 are activated by extracellular protons, ASIC4 and the closely related bile acid-sensitive ion channel (BASIC or ASIC5) are orphan receptors. Neuropeptides are important modulators of ASICs. Moreover, related DEG/ENaCs are directly activated by neuropeptides, rendering neuropeptides interesting ligands of ASICs. Here, we performed an unbiased screen of 109 short neuropeptides (<20 amino acids) on fve homomeric ASICs: ASIC1a, ASIC1b, ASIC3, ASIC4 and BASIC. This screen revealed no direct agonist of any ASIC but three modulators. First, dynorphin A as a modulator of ASIC1a, which increased currents of partially desensitized channels; second, YFMRFamide as a modulator of ASIC1b and ASIC3, which decreased currents of ASIC1b and slowed desensitization of ASIC1b and ASIC3; and, third, endomorphin-1 as a modulator of ASIC3, which also slowed desensitization. With the exception of YFMRFamide, which, however, is not a mammalian neuropeptide, we identifed no new modulator of ASICs. In summary, our screen confrmed some known peptide modulators of ASICs but identifed no new peptide ligands of ASICs, suggesting that most short peptides acting as ligands of ASICs are already known. Acid-sensing ion channels form a small family of proton-gated ion channels that belongs to the degenerin/epi- thelial Na+ channel (DEG/ENaC) gene family1.
    [Show full text]
  • Opioid Receptors: Structural and Mechanistic Insights Into Pharmacology and Signaling
    European Journal of Pharmacology ∎ (∎∎∎∎) ∎∎∎–∎∎∎ Contents lists available at ScienceDirect European Journal of Pharmacology journal homepage: www.elsevier.com/locate/ejphar Opioid receptors: Structural and mechanistic insights into pharmacology and signaling Yi Shang, Marta Filizola n Icahn School of Medicine at Mount Sinai, Department of Structural and Chemical Biology, One Gustave, L. Levy Place, Box 1677, New York, NY 10029, USA article info abstract Article history: Opioid receptors are important drug targets for pain management, addiction, and mood disorders. Al- Received 25 January 2015 though substantial research on these important subtypes of G protein-coupled receptors has been Received in revised form conducted over the past two decades to discover ligands with higher specificity and diminished side 2 March 2015 effects, currently used opioid therapeutics remain suboptimal. Luckily, recent advances in structural Accepted 11 May 2015 biology of opioid receptors provide unprecedented insights into opioid receptor pharmacology and signaling. We review here a few recent studies that have used the crystal structures of opioid receptors as Keywords: a basis for revealing mechanistic details of signal transduction mediated by these receptors, and for the GPCRs purpose of drug discovery. Opioid binding & 2015 Elsevier B.V. All rights reserved. Receptor Molecular dynamics Allosteric modulators Virtual screening Functional selectivity Dimerization 1. Introduction been devoted over the years to reduce the disadvantages of these drugs while retaining their therapeutic efficacy. In the absence of Opioid receptors belong to the super-family of G-protein cou- high-resolution crystal structures of opioid receptors until 2012, pled receptors (GPCRs), which are by far the most abundant class the majority of these efforts used ligand-based strategies, although of cell-surface receptors, and also the targets of about one-third of some also resorted to rudimentary molecular models of the re- approved/marketed drugs (Vortherms and Roth, 2005).
    [Show full text]