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Maguire DR, France CP. Daily methocinnamox treatment dose-dependently attenuates fentanyl self-administration in rhesus monkeys. Neuropharmacology 2024; 243:109777. [PMID: 37944894 DOI: 10.1016/j.neuropharm.2023.109777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/26/2023] [Accepted: 10/22/2023] [Indexed: 11/12/2023]
Abstract
Opioid use disorder and opioid overdose continue to be significant public health challenges despite the availability of effective treatments. Methocinnamox (MCAM) is a novel, long-acting opioid receptor antagonist that might be an effective treatment for opioid use disorder (i.e., preventing relapse and overdose). In nonhuman primates, MCAM selectively blocks the positive reinforcing effects of mu opioid receptor agonists, including heroin, fentanyl, and its ultra-potent analogs (e.g., carfentanil) with a single administration of MCAM being effective for up to two weeks. Because treatment of opioid use disorder would involve repeated administration of a medication, MCAM was studied in rhesus monkeys (3 males and 2 females) responding under a fixed-ratio self-administration procedure for a range of doses of fentanyl (0.000032-0.1 mg/kg/infusion). The fentanyl self-administration dose-effect curve was determined before and during treatment with progressively increasing daily doses of MCAM (0.001-0.1 mg/kg) given subcutaneously 1 h before the session. MCAM dose-dependently shifted the fentanyl dose-effect curve rightward and then, at larger doses, downward. The largest treatment dose of MCAM (0.1 mg/kg/day) shifted the curve more than 120-fold rightward with monkeys receiving doses much larger than the likely lethal dose of fentanyl with no adverse effect or observable change in behavior. This study demonstrates that MCAM reliably and dose-dependently decreases fentanyl self-administration and prevents opioid overdose, with no evidence of adverse effects over a broad dose range, further supporting the potential therapeutic utility of this novel antagonist.
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Affiliation(s)
- David R Maguire
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA; Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA
| | - Charles P France
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA; Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA; Department of Psychiatry, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA.
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2
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Maguire DR. Interactions between lorcaserin and opioids: Ventilation and food-versus-drug choice. Pharmacol Biochem Behav 2024; 234:173673. [PMID: 37951365 DOI: 10.1016/j.pbb.2023.173673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/14/2023]
Abstract
Lorcaserin, a selective serotonin 2C (5-HT2C) receptor agonist, was approved for treating obesity and has been investigated for treating substance use disorders including those involving opioids. Although lorcaserin was withdrawn from the market, interest in the therapeutic potential of drugs acting at 5-HT2C receptors continues, supporting the need to further characterize potential adverse effects especially when combined with drugs of abuse. This study examined acute effects of lorcaserin on opioid-induced ventilatory depression, which is the primary cause of overdose, and opioid self-administration, which models factors contributing to opioid abuse, in male and female rhesus monkeys. In one group (n = 4), effects of morphine (0.178 to 5.6 mg/kg, s.c.), fentanyl (0.0032 to 0.1 mg/kg, s.c.), and lorcaserin (0.1 to 1.78 mg/kg, s.c.) alone as well as effects of lorcaserin with each opioid on ventilation were determined using head plethysmography. Another group (n = 5) responded under a food versus fentanyl (0.1 to 3.2 μg/kg/infusion, i.v.) choice procedure, and lorcaserin (0.32 to 1.78 mg/kg, i.v.) was given as a pretreatment. Lorcaserin dose-dependently decreased minute volume to below 70 % of baseline when administered alone and increased the potency of morphine and fentanyl. Consistent with previous studies, lorcaserin failed to alter choice of fentanyl over food. This study demonstrates the novel finding that lorcaserin alone decreases ventilation and enhances the ventilatory-depressant effects of opioids. Taken together with previous studies, these results suggest that combining a 5-HT2C receptor agonist such as lorcaserin with an opioid could increase the risk of ventilatory depression without the benefit of decreasing abuse.
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Affiliation(s)
- David R Maguire
- Department of Pharmacology and Addiction Research, Treatment & Training Center of Excellence, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX 78229, USA.
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3
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Tabanelli R, Brogi S, Calderone V. Targeting Opioid Receptors in Addiction and Drug Withdrawal: Where Are We Going? Int J Mol Sci 2023; 24:10888. [PMID: 37446064 DOI: 10.3390/ijms241310888] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 06/14/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
This review article offers an outlook on the use of opioids as therapeutics for treating several diseases, including cancer and non-cancer pain, and focuses the analysis on the opportunity to target opioid receptors for treating opioid use disorder (OUD), drug withdrawal, and addiction. Unfortunately, as has been well established, the use of opioids presents a plethora of side effects, such as tolerance and physical and physiological dependence. Accordingly, considering the great pharmacological potential in targeting opioid receptors, the identification of opioid receptor ligands devoid of most of the adverse effects exhibited by current therapeutic agents is highly necessary. To this end, herein, we analyze some interesting molecules that could potentially be useful for treating OUD, with an in-depth analysis regarding in vivo studies and clinical trials.
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Affiliation(s)
- Rita Tabanelli
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Simone Brogi
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Vincenzo Calderone
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy
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Gerak LR, France CP. Attenuation of the Positive-Reinforcing Effects of Ultra-Potent Fentanyl Analogs, Along with Those of Fentanyl and Heroin, During Daily Treatment with Methocinnamox in Rhesus Monkeys. J Pharmacol Exp Ther 2023; 384:363-371. [PMID: 36575032 PMCID: PMC9976789 DOI: 10.1124/jpet.122.001267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 11/22/2022] [Accepted: 12/13/2022] [Indexed: 12/28/2022] Open
Abstract
Without substantial intervention, the opioid crisis is projected to continue, underscoring the need to develop new treatments for opioid use disorder (OUD). One drug under development is the µ opioid receptor antagonist methocinnamox (MCAM), which appears to offer advantages over currently available medications; however, some questions remain about its potential utility, including its ability to block the effects of ultra-potent fentanyl analogs. The goal of this study was to examine its effectiveness in attenuating the abuse-related effects of the fentanyl analogs carfentanil and 3-methylfentanyl in monkeys responding for food or intravenous infusions under a choice procedure. These drugs were compared with fentanyl, heroin, methamphetamine, and cocaine. Food was preferred over saline, and there was a dose-dependent increase in responding for drug over food with no marked decrease in response rates or number of choice trials completed for any of the six drugs studied. Naltrexone (0.032 mg/kg) antagonized choice of µ opioid receptor agonists, producing rightward shifts in dose-effect curves ranging from 27-fold (carfentanil) to 71-fold (heroin). In contrast, naltrexone was less effective in attenuating choice of methamphetamine or cocaine with curves obtained in the presence of naltrexone shifted <3-fold. Daily treatment with 0.032 mg/kg MCAM also antagonized the effects of opioids, shifting curves 20-fold (fentanyl) to 72-fold (heroin) rightward; MCAM did not significantly change dose-effect curves for methamphetamine or cocaine. Thus, antagonism by MCAM is similar across a variety of µ opioid receptor agonists, including ultra-potent fentanyl analogs, further supporting its potential utility as a treatment for OUD. SIGNIFICANCE STATEMENT: Treatments for opioid use disorder (OUD) should attenuate the effects of a variety of opioids, including emerging threats like the ultra-potent fentanyl analogs. The novel µ opioid receptor antagonist MCAM is being developed to treat OUD because it provides long-lasting blockade of the reinforcing effects of heroin and fentanyl. The current study shows that MCAM attenuates the abuse-related effects of the fentanyl analogs carfentanil and 3-methylfentanyl, further supporting the utility of MCAM as a treatment for OUD.
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Affiliation(s)
- Lisa R Gerak
- Department of Pharmacology (L.R.G., C.P.F.) and Department of Psychiatry (C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Addiction Research, Treatment, & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, Texas (L.R.G., C.P.F.)
| | - Charles P France
- Department of Pharmacology (L.R.G., C.P.F.) and Department of Psychiatry (C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Addiction Research, Treatment, & Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, Texas (L.R.G., C.P.F.)
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5
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Maguire DR, France CP. Behavioral pharmacology of methocinnamox: A potential new treatment for opioid overdose and opioid use disorder. J Exp Anal Behav 2023; 119:392-406. [PMID: 36759567 PMCID: PMC10281830 DOI: 10.1002/jeab.831] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 12/28/2022] [Indexed: 02/11/2023]
Abstract
Opioid overdose and opioid use disorder continue to be significant public health challenges despite the availability of effective medications and significant efforts at all levels of society. The emergence of highly potent and efficacious opioids such as fentanyl and its derivatives over the last decade has only exacerbated what was already a substantial problem. Behavioral pharmacology research has proven invaluable for understanding the effects of drugs as well as developing and evaluating pharmacotherapies for disorders involving the central nervous system, including substance abuse disorders. This paper describes a program of research characterizing a potent, selective, and long-lasting mu opioid receptor antagonist, methocinnamox, and evaluating its potential for treating opioid overdose and opioid use disorder. Studies in rodents and nonhuman primates demonstrate that methocinnamox prevents and reverses opioid-induced ventilatory depression and selectively blocks opioid self-administration. This work, taken together with rigorous in vitro and ex vivo studies investigating methocinnamox neuropharmacology, lays a solid foundation for the therapeutic utility of this potentially life-saving medication. Moreover, these studies demonstrate how rigorous behavioral pharmacological studies can be integrated in a broader drug discovery and development research program.
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Affiliation(s)
- David R. Maguire
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, TX, United States
- Addiction Research, Treatment, and Training, Center of Excellence, University of Texas, Health Science Center at San Antonio, TX, United States
| | - Charles P. France
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, TX, United States
- Addiction Research, Treatment, and Training, Center of Excellence, University of Texas, Health Science Center at San Antonio, TX, United States
- Department of Psychiatry, University of Texas, Health Science Center at San Antonio, TX, United States
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Maguire DR, France CP. Effects of Daily Methocinnamox Treatment on Fentanyl Self-Administration in Rhesus Monkeys. J Pharmacol Exp Ther 2022; 382:181-187. [PMID: 35643857 PMCID: PMC9341267 DOI: 10.1124/jpet.122.001233] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 05/04/2022] [Indexed: 08/03/2023] Open
Abstract
Methocinnamox (MCAM), a long-acting μ-opioid receptor antagonist, attenuates the positive reinforcing effects of opioids, such as heroin and fentanyl, suggesting it could be an effective treatment of opioid use disorder (OUD). Because treatment of OUD often involves repeated administration of a medication, this study evaluated effects of daily injections of a relatively small dose of MCAM on fentanyl self-administration and characterized the shift in the fentanyl dose-effect curve. Rhesus monkeys (3 males and 2 females) lever-pressed for intravenous infusions of fentanyl (0.032-10 μg/kg infusion) or cocaine (32-100 μg/kg infusion) under a fixed-ratio 30 schedule. MCAM (0.032 mg/kg) or naltrexone (0.0032-0.032 mg/kg) was administered subcutaneously 60 or 15 minutes, respectively, before sessions. When administered acutely, naltrexone and MCAM decreased fentanyl self-administration, with effects of naltrexone lasting less than 24 hours and effects of MCAM lasting for up to 3 days. Daily MCAM treatment attenuated responding for fentanyl, but not cocaine; effects were maintained for the duration of treatment with responding recovering quickly (within 2 days) following discontinuation of treatment. MCAM treatment shifted the fentanyl dose-effect curve in a parallel manner approximately 20-fold to the right. Naltrexone pretreatment decreased fentanyl intake with equal potency before and after MCAM treatment, confirming sensitivity of responding to antagonism by an opioid receptor antagonist. Although antagonist effects of treatment with a relatively small dose were surmountable, MCAM produced sustained and selective attenuation of opioid self-administration, supporting the view that it could be an effective treatment of OUD. SIGNIFICANCE STATEMENT: Opioid use disorder and opioid overdose continue to be significant public health challenges despite the availability of effective treatments. Methocinnamox (MCAM) is a long-acting μ-opioid receptor antagonist that blocks the reinforcing and ventilatory depressant effects of opioids in nonhuman subjects. This study demonstrates that daily treatment with MCAM reliably and selectively decreases fentanyl self-administration, further supporting the potential therapeutic utility of this novel antagonist.
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Affiliation(s)
- David R Maguire
- Department of Pharmacology, (D.R.M., C.P.F.), Addiction Research, Treatment & Training Center of Excellence (D.R.M., C.P.F.), and Department of Psychiatry (C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Charles P France
- Department of Pharmacology, (D.R.M., C.P.F.), Addiction Research, Treatment & Training Center of Excellence (D.R.M., C.P.F.), and Department of Psychiatry (C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas
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The Potential of Methocinnamox as a Future Treatment for Opioid Use Disorder: A Narrative Review. PHARMACY 2022; 10:pharmacy10030048. [PMID: 35645327 PMCID: PMC9149874 DOI: 10.3390/pharmacy10030048] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/15/2022] [Accepted: 04/16/2022] [Indexed: 02/01/2023] Open
Abstract
The opioid epidemic is an ongoing public health crisis, and the United States health system is overwhelmed with increasing numbers of opioid-related overdoses. Methocinnamox (MCAM) is a novel mu opioid receptor antagonist with an extended duration of action. MCAM has potential to reduce the burden of the opioid epidemic by being used as an overdose rescue treatment and a long-term treatment for opioid use disorder (OUD). The currently available treatments for OUD include naloxone, naltrexone, and methadone. These treatments have certain limitations, which include short duration of action, patient non-compliance, and diversion. A narrative review was conducted using PubMed and Google Scholar databases covering the history of the opioid epidemic, pain receptors, current OUD treatments and the novel drug MCAM. MCAM could potentially be used as both a rescue and long-term treatment for opioid misuse. This is due to its pseudo-irreversible antagonism of the mu opioid receptor, abnormally long duration of action of nearly two weeks, and the possibility of using kappa or delta opioid receptor agonists for pain management during OUD treatment. MCAM’s novel pharmacokinetic and pharmacodynamic properties open a new avenue for treating opioid misuse.
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Abstract
This paper is the forty-second consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2019 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY, 11367, United States.
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Choi MR, Jin YB, Kim HN, Chai YG, Im CN, Lee SR, Kim DJ. Gene expression in the striatum of cynomolgus monkeys after chronic administration of cocaine and heroin. Basic Clin Pharmacol Toxicol 2021; 128:686-698. [PMID: 33404192 DOI: 10.1111/bcpt.13554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 12/26/2020] [Accepted: 01/01/2021] [Indexed: 01/16/2023]
Abstract
Cocaine and heroin cause impairment of neural plasticity in the brain including striatum. This study aimed to identify genes differentially expressed in the striatum of cynomolgus monkeys in response to cocaine and heroin. After chronic administration of cocaine and heroin in the monkeys, we performed large-scale transcriptome profiling in the striatum using RNA-Seq technology and analysed functional annotation. We found that 547 and 1238 transcripts were more than 1.5-fold up- or down-regulated in cocaine- and heroin-treated groups, respectively, compared to the control group, and 3432 transcripts exhibited differential expression between cocaine- and heroin-treated groups. Functional annotation analysis indicated that genes associated with nervous system development (NAGLU, MOBP and TTL7) and stress granule disassembly (KIF5B and KLC1) were differentially expressed in the cocaine-treated group compared to the control group, whereas gene associated with neuron apoptotic process (ERBB3) was differentially expressed in the heroin-treated group. In addition, IPA network analysis indicated that genes (TRAF6 and TRAF3IP2) associated with inflammation were increased by the chronic administration of cocaine and heroin. These results provide insight into the correlated molecular mechanisms as well as the upregulation and down-regulation of genes in the striatum after chronic exposure to cocaine and heroin.
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Affiliation(s)
- Mi Ran Choi
- Department of Psychiatry, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea
| | - Yeung-Bae Jin
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Han-Na Kim
- National Primate Research Center (NPRC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju, Republic of Korea
| | - Young Gyu Chai
- Department of Molecular and Life Sciences, Hanyang University, Ansan, Republic of Korea
| | - Chang-Nim Im
- Department of Psychiatry, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea
| | - Sang-Rae Lee
- National Primate Research Center (NPRC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju, Republic of Korea.,Department of Functional Genomics, University of Science and Technology, Daejeon, Republic of Korea
| | - Dai-Jin Kim
- Department of Psychiatry, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea
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Translational value of non-human primates in opioid research. Exp Neurol 2021; 338:113602. [PMID: 33453211 DOI: 10.1016/j.expneurol.2021.113602] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/06/2021] [Accepted: 01/10/2021] [Indexed: 01/02/2023]
Abstract
Preclinical opioid research using animal models not only provides mechanistic insights into the modulation of opioid analgesia and its associated side effects, but also validates drug candidates for improved treatment options for opioid use disorder. Non-human primates (NHPs) have served as a surrogate species for humans in opioid research for more than five decades. The translational value of NHP models is supported by the documented species differences between rodents and primates regarding their behavioral and physiological responses to opioid-related ligands and that NHP studies have provided more concordant results with human studies. This review highlights the utilization of NHP models in five aspects of opioid research, i.e., analgesia, abuse liability, respiratory depression, physical dependence, and pruritus. Recent NHP studies have found that (1) mixed mu opioid and nociceptin/orphanin FQ peptide receptor partial agonists appear to be safe, non-addictive analgesics and (2) mu opioid receptor- and mixed opioid receptor subtype-based medications remain the only two classes of drugs that are effective in alleviating opioid-induced adverse effects. Given the recent advances in pharmaceutical sciences and discoveries of novel targets, NHP studies are posed to identify the translational gap and validate therapeutic targets for the treatment of opioid use disorder. Pharmacological studies using NHPs along with multiple outcome measures (e.g., behavior, physiologic function, and neuroimaging) will continue to facilitate the research and development of improved medications to curb the opioid epidemic.
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11
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Jimenez VM, Castaneda G, France CP. Methocinnamox Reverses and Prevents Fentanyl-Induced Ventilatory Depression in Rats. J Pharmacol Exp Ther 2021; 377:29-38. [PMID: 33431611 DOI: 10.1124/jpet.120.000387] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 01/06/2021] [Indexed: 11/22/2022] Open
Abstract
Opioid use disorder affects over 2 million Americans with an increasing number of deaths due to overdose from the synthetic opioid fentanyl and its analogs. The Food and Drug Administration-approved opioid receptor antagonist naloxone (e.g., Narcan) is used currently to treat overdose; however, a short duration of action limits its clinical utility. Methocinnamox (MCAM) is a long-lasting opioid receptor antagonist that may reverse and prevent the ventilatory-depressant effects of fentanyl. This study compared the ability of naloxone (0.0001-10 mg/kg) and MCAM (0.0001-10 mg/kg) to reverse and prevent ventilatory depression by fentanyl and compared the duration of action of MCAM intravenously and subcutaneously in two procedures: ventilation and warm-water tail withdrawal. In male Sprague-Dawley rats (N = 8), fentanyl (0.0032-0.178 mg/kg, i.v.) decreased minute volume in a dose- and time-dependent manner with a dose of 0.178 mg/kg decreasing VE to less than 40% of control. MCAM and naloxone reversed the ventilatory-depressant effects of 0.178 mg/kg fentanyl in a dose-related manner. The day after antagonist administration, MCAM but not naloxone attenuated the ventilatory-depressant effects of fentanyl. The duration of action of MCAM lasted up to 3 days and at least 2 weeks after intravenous and subcutaneous administration, respectively. MCAM attenuated the antinociceptive effects of fentanyl, with antagonism lasting up to 5 days and more than 2 weeks after intravenous and subcutaneous administration, respectively. Reversal and prolonged antagonism by MCAM might provide an effective treatment option for the opioid crisis, particularly toxicity from fentanyl and related highly potent analogs. SIGNIFICANCE STATEMENT: This study demonstrates that like naloxone, methocinnamox (MCAM) reverses the ventilatory-depressant effects of fentanyl in a time- and dose-related manner. However, unlike naloxone, the duration of action of MCAM was greater than 2 weeks when administered subcutaneously and up to 5 days when administered intravenously. These data suggest that MCAM might be particularly useful for rescuing individuals from opioid overdose, including fentanyl overdose, as well as protecting against the reemergence of ventilatory depression (renarconization).
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Affiliation(s)
- Victor M Jimenez
- Departments of Pharmacology (V.M.J., G.C., C.P.F.), Psychiatry (C.P.F.), and Addiction Research, Treatment and Training Center of Excellence (V.M.J., G.C., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Gabriel Castaneda
- Departments of Pharmacology (V.M.J., G.C., C.P.F.), Psychiatry (C.P.F.), and Addiction Research, Treatment and Training Center of Excellence (V.M.J., G.C., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Charles P France
- Departments of Pharmacology (V.M.J., G.C., C.P.F.), Psychiatry (C.P.F.), and Addiction Research, Treatment and Training Center of Excellence (V.M.J., G.C., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas
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12
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France CP, Ahern GP, Averick S, Disney A, Enright HA, Esmaeli-Azad B, Federico A, Gerak LR, Husbands SM, Kolber B, Lau EY, Lao V, Maguire DR, Malfatti MA, Martinez G, Mayer BP, Pravetoni M, Sahibzada N, Skolnick P, Snyder EY, Tomycz N, Valdez CA, Zapf J. Countermeasures for Preventing and Treating Opioid Overdose. Clin Pharmacol Ther 2020; 109:578-590. [PMID: 33113208 DOI: 10.1002/cpt.2098] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/15/2020] [Indexed: 02/06/2023]
Abstract
The only medication available currently to prevent and treat opioid overdose (naloxone) was approved by the US Food and Drug Administration (FDA) nearly 50 years ago. Because of its pharmacokinetic and pharmacodynamic properties, naloxone has limited utility under some conditions and would not be effective to counteract mass casualties involving large-scale deployment of weaponized synthetic opioids. To address shortcomings of current medical countermeasures for opioid toxicity, a trans-agency scientific meeting was convened by the US National Institute of Allergy and Infectious Diseases/National Institutes of Health (NIAID/NIH) on August 6 and 7, 2019, to explore emerging alternative approaches for treating opioid overdose in the event of weaponization of synthetic opioids. The meeting was initiated by the Chemical Countermeasures Research Program (CCRP), was organized by NIAID, and was a collaboration with the National Institute on Drug Abuse/NIH (NIDA/NIH), the FDA, the Defense Threat Reduction Agency (DTRA), and the Biomedical Advanced Research and Development Authority (BARDA). This paper provides an overview of several presentations at that meeting that discussed emerging new approaches for treating opioid overdose, including the following: (1) intranasal nalmefene, a competitive, reversible opioid receptor antagonist with a longer duration of action than naloxone; (2) methocinnamox, a novel opioid receptor antagonist; (3) covalent naloxone nanoparticles; (4) serotonin (5-HT)1A receptor agonists; (5) fentanyl-binding cyclodextrin scaffolds; (6) detoxifying biomimetic "nanosponge" decoy receptors; and (7) antibody-based strategies. These approaches could also be applied to treat opioid use disorder.
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Affiliation(s)
- Charles P France
- Department of Pharmacology, Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center, San Antonio, Texas, USA
| | | | - Saadyah Averick
- Neuroscience Institute, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Alex Disney
- Department of Pharmacy and Pharmacology, University of Bath, Bath, UK
| | | | - Babak Esmaeli-Azad
- CellCure (Stem Cell Division of CiBots, Inc.), San Diego, California, USA
| | - Arianna Federico
- CellCure (Stem Cell Division of CiBots, Inc.), San Diego, California, USA
| | - Lisa R Gerak
- Department of Pharmacology, Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center, San Antonio, Texas, USA
| | | | | | - Edmond Y Lau
- Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Victoria Lao
- Lawrence Livermore National Laboratory, Livermore, California, USA
| | - David R Maguire
- Department of Pharmacology, Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center, San Antonio, Texas, USA
| | | | - Girardo Martinez
- CellCure (Stem Cell Division of CiBots, Inc.), San Diego, California, USA
| | - Brian P Mayer
- Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Marco Pravetoni
- Department of Pharmacology, Center for Immunology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | | | - Phil Skolnick
- Opiant Pharmaceuticals, Inc., Santa Monica, California, USA
| | - Evan Y Snyder
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Nestor Tomycz
- Neuroscience Institute, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Carlos A Valdez
- Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Jim Zapf
- CellCure (Stem Cell Division of CiBots, Inc.), San Diego, California, USA
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13
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Effects of acute and repeated treatment with methocinnamox, a mu opioid receptor antagonist, on fentanyl self-administration in rhesus monkeys. Neuropsychopharmacology 2020; 45:1986-1993. [PMID: 32375158 PMCID: PMC7547678 DOI: 10.1038/s41386-020-0698-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/13/2020] [Accepted: 04/27/2020] [Indexed: 11/08/2022]
Abstract
Methocinnamox (MCAM), a mu opioid receptor antagonist with a long duration of action, attenuates heroin self-administration in rhesus monkeys, suggesting it could be an effective treatment for opioid use disorder (OUD). This study examined effects of acute and repeated MCAM administration on self-administration of the high-efficacy mu opioid receptor agonist fentanyl and characterized MCAM pharmacokinetics. Four rhesus monkeys self-administered i.v. infusions of fentanyl (0.00032 mg/kg/infusion) or cocaine (0.032 mg/kg/infusion). MCAM (0.1-0.32 mg/kg) or the opioid receptor antagonist naltrexone (0.001-0.032 mg/kg) was injected prior to test sessions to evaluate acute effects. On a separate occasion, 0.32 mg/kg MCAM was injected every 12 days for 5 total injections to evaluate the effectiveness of repeated treatment. Following acute injection, MCAM and naltrexone decreased fentanyl self-administration on the day of treatment, with attenuation lasting for up to 2 weeks after the larger MCAM dose and <1 day after naltrexone. Repeated MCAM administration decreased fentanyl self-administration for more than 2 months without altering cocaine self-administration. MCAM plasma concentrations peaked 15-45 min after injection, with a half-life ranging from 13.7 to 199.8 min, and decreased markedly 1 day after injection. MCAM selectively reduced opioid self-administration and remained effective with repeated administration. Moreover, MCAM was effective at times when plasma levels were very low, suggesting that pharmacodynamic (i.e., pseudoirreversible binding to mu opioid receptors) and not pharmacokinetic factors play a significant role in its long-lasting effects. Taken together with previous studies, these data indicate that MCAM could be a safe, effective, and long-acting treatment for OUD.
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14
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Townsend EA. The lasting impact of methocinnamox on opioid self-administration. Neuropsychopharmacology 2020; 45:1963-1964. [PMID: 32444781 PMCID: PMC7547696 DOI: 10.1038/s41386-020-0717-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 05/12/2020] [Indexed: 11/09/2022]
Affiliation(s)
- E Andrew Townsend
- Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA.
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15
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Methocinnamox (MCAM) antagonizes the behavioral suppressant effects of morphine without impairing delayed matching-to-sample accuracy in rhesus monkeys. Psychopharmacology (Berl) 2020; 237:3057-3065. [PMID: 32772146 PMCID: PMC8114947 DOI: 10.1007/s00213-020-05592-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 06/12/2020] [Indexed: 12/16/2022]
Abstract
RATIONALE Opioid abuse remains a serious public health problem. The pseudoirreversible mu opioid receptor antagonist methocinnamox (MCAM) might be useful for treating opioid abuse and overdose. Because endogenous opioid systems can modulate cognition and decision-making, it is important to evaluate whether long-term blockade of mu opioid receptors by MCAM adversely impacts complex operant behavior involving memory. OBJECTIVE This study tested the effects of MCAM in rhesus monkeys responding under a delayed matching-to-sample task, with correct responses reinforced by sucrose pellets. Because MCAM did not alter performance, antagonism of the rate-decreasing effects of morphine was used to confirm that an effective dose of MCAM was administered. Moreover, the muscarinic receptor antagonist scopolamine and the N-methyl-D-aspartate antagonist phencyclidine were studied as positive controls to demonstrate sensitivity of this procedure to memory disruption. RESULTS Neither MCAM (0.32 mg/kg) nor morphine (1-5.6 mg/kg) impaired delayed matching-to-sample accuracy. Morphine dose-dependently decreased the number of trials completed before MCAM administration, and a single injection of MCAM blocked the behavioral suppressant effects of morphine for at least 7 days. Scopolamine (0.01-0.056 mg/kg) and phencyclidine (0.1-0.56 mg/kg) dose-dependently decreased delayed matching-to-sample accuracy and the number of trials completed. CONCLUSIONS MCAM did not impair memory (as measured by accuracy in a delayed matching-to-sample task) and did not decrease responding for or consumption of sucrose pellets. This dose of MCAM attenuates self-administration of opioids and reverses as well as prevents opioid-induced respiratory depression. These results provide further support for a favorable adverse effect profile for MCAM.
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Abstract
This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY, 11367, United States.
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17
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Thomson JS, Deakin AG, Cossins AR, Spencer JW, Young IS, Sneddon LU. Acute and chronic stress prevents responses to pain in zebrafish: evidence for stress-induced analgesia. ACTA ACUST UNITED AC 2020; 223:223/14/jeb224527. [PMID: 32699156 PMCID: PMC7391404 DOI: 10.1242/jeb.224527] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 06/10/2020] [Indexed: 12/31/2022]
Abstract
The state of an animal prior to the application of a noxious stimulus can have a profound effect on their nociceptive threshold and subsequent behaviour. In mammals, the presence of acute stress preceding a painful event can have an analgesic effect whereas the presence of chronic stress can result in hyperalgesia. While considerable research has been conducted on the ability of stress to modulate mammalian responses to pain, relatively little is known about fish. This is of particular concern given that zebrafish (Danio rerio) are an extensively used model organism subject to a wide array of invasive procedures where the level of stress prior to experimentation could pose a major confounding factor. This study, therefore, investigated the impact of both acute and chronic stress on the behaviour of zebrafish subjected to a potentially painful laboratory procedure, the fin clip. In stress-free individuals, those subjected to the fin clip spent more time in the bottom of the tank, had reduced swimming speeds and less complex swimming trajectories; however, these behavioural changes were absent in fin-clipped fish that were first subject to either chronic or acute stress, suggesting the possibility of stress-induced analgesia (SIA). To test this, the opioid antagonist naloxone was administered to fish prior to the application of both the stress and fin-clip procedure. After naloxone, acutely stressed fin-clipped zebrafish exhibited the same behaviours as stress-free fin-clipped fish. This indicates the presence of SIA and the importance of opioid signalling in this mechanism. As stress reduced nociceptive responses in zebrafish, this demonstrates the potential for an endogenous analgesic system akin to the mammalian system. Future studies should delineate the neurobiological basis of stress-induced analgesia in fish. Summary: Exposure of zebrafish to acute or chronic stress prior to fin clipping prevents behavioural changes normally seen after fin clip; naloxone treatment prevented this effect, demonstrating stress-induced analgesia.
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Affiliation(s)
- Jack S Thomson
- School of Environmental Sciences, University of Liverpool, Liverpool L69 3GP, UK
| | - Anthony G Deakin
- Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, UK.,Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Andrew R Cossins
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Joseph W Spencer
- Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, UK
| | - Iain S Young
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Lynne U Sneddon
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
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18
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Gerak LR, Maguire DR, France CP. Behavioral Pharmacology of Drugs Acting at Mu Opioid Receptors. Handb Exp Pharmacol 2020; 258:127-145. [PMID: 31451969 DOI: 10.1007/164_2019_265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Despite the therapeutic utility of opioids for relieving pain, other behavioral effects, including their potential for abuse and overdose, can be quite detrimental to individuals as well as society and have contributed to the ongoing opioid crisis. The dramatic escalation in overdose deaths over the last 15 years was initially driven by abuse of prescription opioids, although abuse of heroin, fentanyl, and fentanyl analogs has been increasing, largely due to increased availability and lower cost compared with prescription opioids. All of these opioids share pharmacological properties, acting as agonists at mu opioid receptors, and produce similar behavioral effects, including abuse-related, pain-relieving, dependence-producing, and respiratory-depressant effects. Despite their similarities, opioids are not pharmacologically identical. In fact, drugs that act at mu opioid receptors, including abused opioids, can vary on a number of dimensions, including pharmacological efficacy, drug-receptor interactions, receptor selectivity, and pharmacokinetics. Overall, these differences impact behavioral effects of drugs acting at mu opioid receptors, and this chapter describes variations in those behavioral effects and how these differences continue to provide new strategies that can be developed to address the ongoing opioid epidemic.
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Affiliation(s)
- Lisa R Gerak
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - David R Maguire
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Charles P France
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Addiction Research, Treatment and Training Center of Excellence, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Department of Psychiatry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
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19
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Yeung DT, Bough KJ, Harper JR, Platoff GE. National Institutes of Health (NIH) Executive Meeting Summary: Developing Medical Countermeasures to Rescue Opioid-Induced Respiratory Depression (a Trans-Agency Scientific Meeting)-August 6/7, 2019. J Med Toxicol 2020; 16:87-105. [PMID: 31853736 PMCID: PMC6942061 DOI: 10.1007/s13181-019-00750-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/13/2019] [Accepted: 11/18/2019] [Indexed: 01/25/2023] Open
Abstract
On August 6th, 2019, a two-day trans-agency scientific meeting was convened by the United States (U.S.) National Institute of Allergy and Infectious Diseases (NIAID/NIH) on the research and development of medical countermeasures (MCMs) and treatment strategies to mitigate synthetic opioid-induced toxicities. This trans-agency meeting was an initiative of the Chemical Countermeasures Research Program (CCRP) and organized by the NIAID in collaboration with the National Institute of Drug Abuse (NIDA), the Biomedical Advanced Research and Development Authority (BARDA), the Food and Drug Administration (FDA), and the Defense Threat Reduction Agency (DTRA). The CCRP is part of the larger NIH biodefense research program coordinated by NIAID, which also includes MCM research and development programs against biological, radiological, and nuclear threats. Its overarching goal is to integrate cutting-edge research and technological advances in science and medicine to enhance the nation's medical response capabilities during and after a public health emergency involving the deliberate or accidental release of toxic chemicals. The potential of a mass casualty public health event involving synthetic opioids is a rapidly growing concern. As such, the overall goals of this trans-agency meeting are to better understand opioid-induced toxicities and advance the development of MCMs to mitigate and reverse opioid-induced respiratory depression (OIRD) to prevent consequential mortality. The primary objectives of the meeting were (1) highlight the latest research on mechanisms of OIRD and related toxicities, animal models, diagnostics, delivery technologies, and emerging new treatment options to prevent lethality; (2) identify current knowledge gaps to advance medical countermeasure development; (3) hear from the U.S. FDA on regulatory considerations to support new technology and treatment approaches; and (4) provide a forum for networking and collaborative partnerships. To accomplish this, a diverse group of almost 200 US domestic and international subject matter experts spanning fundamental and translational research from academia, industry, and government came together in-person to share their collective expertise and experience in this important field. This report briefly summarizes the information presented throughout the meeting, which was also webcast live in its entirety to registered remote attendees.
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Affiliation(s)
- David T Yeung
- National Institute of Allergy and Infectious Diseases/National Institutes of Health (NIAID/NIH), Bethesda, MD, USA.
| | - Kristopher J Bough
- National Institute of Drug Abuse/National Institutes of Health (NIDA/NIH), Bethesda, MD, USA
| | - Jill R Harper
- National Institute of Allergy and Infectious Diseases/National Institutes of Health (NIAID/NIH), Bethesda, MD, USA
| | - Gennady E Platoff
- National Institute of Allergy and Infectious Diseases/National Institutes of Health (NIAID/NIH), Bethesda, MD, USA
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20
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Gerak LR, Minervini V, Latham E, Ghodrati S, Lillis KV, Wooden J, Disney A, Husbands SM, France CP. Methocinnamox Produces Long-Lasting Antagonism of the Behavioral Effects of µ-Opioid Receptor Agonists but Not Prolonged Precipitated Withdrawal in Rats. J Pharmacol Exp Ther 2019; 371:507-516. [PMID: 31439807 DOI: 10.1124/jpet.119.260331] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 08/19/2019] [Indexed: 01/10/2023] Open
Abstract
A novel µ-opioid receptor antagonist, methocinnamox (MCAM), attenuates some abuse-related and toxic effects of opioids. This study further characterized the pharmacology of MCAM in separate groups of rats using procedures to examine antinociception, gastrointestinal motility, and withdrawal in morphine-dependent rats. Antinociceptive effects of opioid receptor agonists were measured before and after MCAM (1-10 mg/kg) using warm water tail withdrawal and sensitivity to mechanical stimulation in inflamed paws (complete Freund's adjuvant). Before MCAM, morphine, fentanyl, and the κ-opioid receptor agonist spiradoline dose dependently increased tail-withdrawal latency from 50°C water; MCAM attenuated the antinociceptive effects of morphine and fentanyl, but not spiradoline. Morphine increased sensitivity to mechanical stimulation and decreased gastrointestinal motility, and MCAM blocked both effects. These antagonist effects of 10 mg/kg MCAM were persistent, lasting for 2 weeks or longer. Withdrawal emerged after discontinuation of morphine treatment or administration of 10 mg/kg MCAM or 17.8 mg/kg naloxone; other than the day of antagonist administration when withdrawal signs were greater in rats that received antagonist compared with rats that received vehicle, there was no difference among groups in directly observable withdrawal signs or decreased body weight. These results confirm that MCAM is a selective µ-opioid receptor antagonist with an exceptionally long duration of action, likely due to pseudoirreversible binding. Despite its sustained antagonist effects, the duration of withdrawal precipitated by MCAM is not different from that precipitated by naloxone, suggesting that the long duration of antagonism provided by MCAM could be particularly effective for treating opioid abuse and overdose. SIGNIFICANCE STATEMENT: The opioid receptor antagonist MCAM attenuates some abuse-related and toxic effects of opioids. This study demonstrates that MCAM selectively antagonizes multiple effects mediated by µ-opioid receptor agonists for 2 weeks or longer, and like naloxone, MCAM precipitates withdrawal in morphine-dependent rats. Despite this persistent antagonism, withdrawal signs precipitated by MCAM are not significantly different from signs precipitated by naloxone or occurring after discontinuation of morphine, suggesting that using MCAM for opioid abuse or overdose would not produce sustained withdrawal.
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Affiliation(s)
- Lisa R Gerak
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Vanessa Minervini
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Elizabeth Latham
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Saba Ghodrati
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Katherine V Lillis
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Jessica Wooden
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Alex Disney
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Stephen M Husbands
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
| | - Charles P France
- Departments of Pharmacology (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.) and Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (L.R.G., V.M., E.L., S.G., K.V.L., J.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (A.D., S.M.H.)
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21
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Maguire DR, Gerak LR, Woods JH, Husbands SM, Disney A, France CP. Long-Lasting Effects of Methocinnamox on Opioid Self-Administration in Rhesus Monkeys. J Pharmacol Exp Ther 2019; 368:88-99. [PMID: 30401680 PMCID: PMC11046729 DOI: 10.1124/jpet.118.252353] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/05/2018] [Indexed: 01/05/2023] Open
Abstract
Opioid abuse remains a serious public health challenge, despite the availability of medications that are effective in some patients (naltrexone, buprenorphine, and methadone). This study explored the potential of a pseudoirreversible mu-opioid receptor antagonist [methocinnamox (MCAM)] as a treatment for opioid abuse by examining its capacity to attenuate the reinforcing effects of mu-opioid receptor agonists in rhesus monkeys. In one experiment, monkeys responded for heroin (n = 5) or cocaine (n = 4) under a fixed-ratio schedule. Another group (n = 3) worked under a choice procedure with one alternative delivering food and the other alternative delivering the mu-opioid receptor agonist remifentanil. A third group (n = 4) responded for food and physiologic parameters were measured via telemetry. The effects of MCAM were determined in all experiments and, in some cases, were compared with those of naltrexone. When given immediately before sessions, naltrexone dose-dependently decreased responding for heroin and decreased choice of remifentanil while increasing choice of food, with responding returning to baseline levels 1 day after naltrexone injection. MCAM also decreased responding for heroin and decreased choice of remifentanil while increasing choice of food; however, opioid-maintained responding remained decreased for several days after treatment. Doses of MCAM that significantly decreased opioid-maintained responding did not decrease responding for cocaine or food. MCAM did not impact heart rate, blood pressure, body temperature, or activity at doses that decreased opioid self-administration. Because MCAM selectively attenuates opioid self-administration for prolonged periods, this novel drug could be a safe and effective alternative to currently available treatments for opioid abuse.
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Affiliation(s)
- David R Maguire
- Department of Pharmacology (D.R.M., L.R.G., J.H.W., C.P.F.), Department of Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (D.R.M., L.R.G., J.H.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (S.M.H., A.D.)
| | - Lisa R Gerak
- Department of Pharmacology (D.R.M., L.R.G., J.H.W., C.P.F.), Department of Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (D.R.M., L.R.G., J.H.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (S.M.H., A.D.)
| | - James H Woods
- Department of Pharmacology (D.R.M., L.R.G., J.H.W., C.P.F.), Department of Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (D.R.M., L.R.G., J.H.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (S.M.H., A.D.)
| | - Stephen M Husbands
- Department of Pharmacology (D.R.M., L.R.G., J.H.W., C.P.F.), Department of Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (D.R.M., L.R.G., J.H.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (S.M.H., A.D.)
| | - Alex Disney
- Department of Pharmacology (D.R.M., L.R.G., J.H.W., C.P.F.), Department of Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (D.R.M., L.R.G., J.H.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (S.M.H., A.D.)
| | - Charles P France
- Department of Pharmacology (D.R.M., L.R.G., J.H.W., C.P.F.), Department of Psychiatry (C.P.F.), and Addiction Research, Treatment & Training Center of Excellence (D.R.M., L.R.G., J.H.W., C.P.F.), University of Texas Health Science Center at San Antonio, San Antonio, Texas; and Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom (S.M.H., A.D.)
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