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Mu RJ, Liu TL, Liu XD, Liu L. PBPK-PD model for predicting morphine pharmacokinetics, CNS effects and naloxone antagonism in humans. Acta Pharmacol Sin 2024:10.1038/s41401-024-01255-2. [PMID: 38570601 DOI: 10.1038/s41401-024-01255-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/27/2024] [Indexed: 04/05/2024] Open
Abstract
Morphine and morphine-6-glucuronide (M6G) produce central nervous system (CNS) effects by activating mu-opioid receptors, while naloxone is used mainly for the reversal of opioid overdose, specifically for the fatal complication of respiratory depression, but also for alleviating opioid-induced side effects. In this study we developed a physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) model to simultaneously predict pharmacokinetics and CNS effects (miosis, respiratory depression and analgesia) of morphine as well as antagonistic effects of naloxone against morphine. The pharmacokinetic and pharmacodynamic parameters were obtained from in vitro data, in silico, or animals. Pharmacokinetic and pharmacodynamic simulations were conducted using 39 and 36 clinical reports, respectively. The pharmacokinetics of morphine and M6G following oral or intravenous administration were simulated, and the PBPK-PD model was validated using clinical observations. The Emax model correlated CNS effects with free concentrations of morphine and M6G in brain parenchyma. The predicted CNS effects were compared with observations. Most clinical observations fell within the 5th-95th percentiles of simulations based on 1000 virtual individuals. Most of the simulated area under the concentration-time curve or peak concentrations also fell within 0.5-2-fold of observations. The contribution of morphine to CNS effects following intravenous or oral administration was larger than that of M6G. Pharmacokinetics and antagonistic effects of naloxone on CNS effects were also successfully predicted using the developed PBPK-PD model. In conclusion, the pharmacokinetics and pharmacodynamics of morphine and M6G, antagonistic effects of naloxone against morphine-induced CNS effects may be successfully predicted using the developed PBPK-PD model based on the parameters derived from in vitro, in silico, or animal studies.
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Affiliation(s)
- Rui-Jing Mu
- Department of Pharmacology, College of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Tian-Lei Liu
- Department of Pharmacology, College of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Xiao-Dong Liu
- Department of Pharmacology, College of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Li Liu
- Department of Pharmacology, College of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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Montana MC, McLeland M, Fisher M, Juriga L, Ercole PM, Kharasch ED. Opioid sensitivity in treated and untreated obstructive sleep apnoea: a prospective cohort study. Br J Anaesth 2024; 132:145-153. [PMID: 37945413 PMCID: PMC10797511 DOI: 10.1016/j.bja.2023.09.032] [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: 04/24/2023] [Revised: 09/25/2023] [Accepted: 09/26/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND Opioid administration to patients with obstructive sleep apnoea (OSA) is controversial because they are believed to be more sensitive to opioids. However, objective data on opioid effects in OSA are lacking. We tested the hypothesis that subjects with untreated OSA have increased sensitivity to opioids compared with subjects without OSA, or with OSA treated with continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BIPAP). METHODS This was a single-centre, prospective cohort study in subjects without OSA (n=20), with untreated OSA (n=33), or with treated OSA (n=21). OSA diagnosis was verified using type III (in-home) polysomnography. Subjects received a stepped-dose remifentanil infusion (target effect-site concentrations of 0.5, 1, 2, 3, 4 ng ml-1). Primary outcome was miosis (pupil area fractional change), the most sensitive opioid effect. Secondary outcomes were ventilatory rate, end-expired CO2, sedation, and thermal analgesia. RESULTS There were no differences in miosis between untreated OSA subjects (mean=0.51, 95% confidence interval [CI] 0.41-0.61) and subjects without OSA (mean=0.49, 95% CI 0.36-0.62) (mean difference=0.02, 95% CI -0.18 to 0.22); between treated OSA subjects (mean=0.56, 95% CI 0.43-0.68) and subjects without OSA (difference=0.07, 95% CI -0.16 to 0.29); or between untreated OSA and treated OSA (difference=-0.05, 95% CI -0.25 to 0.16). There were no significant differences between subjects without OSA, untreated OSA, and treated OSA in ventilatory rate, end-expired CO2, sedation, or thermal analgesia responses to remifentanil. There was no relationship between OSA severity and magnitude of opioid effects. CONCLUSIONS Neither obstructive sleep apnoea nor obstructive sleep apnoea treatment affected sensitivity to the miotic, sedative, analgesic, or respiratory depressant effects of the opioid remifentanil in awake adults. These results challenge conventional notions of opioid effects in obstructive sleep apnoea. CLINICAL TRIAL REGISTRATION NCT02898792 (clinicaltrials.gov).
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Affiliation(s)
- Michael C Montana
- Department of Anesthesiology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA.
| | - Michael McLeland
- Sleep Laboratory, Saint Louis Children's Hospital, St. Louis, MO, USA
| | - Marilee Fisher
- Department of Anesthesiology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA; Pediatric Intensive Care Unit, Saint Louis Children's Hospital, St. Louis, MO, USA
| | - Lindsay Juriga
- Department of Anesthesiology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA; University of Missouri School of Medicine, Columbia, MO, USA
| | | | - Evan D Kharasch
- Department of Anesthesiology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA; Department of Anesthesiology, Duke University School of Medicine, Durham, NC, USA
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3
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Meissner K, Dahan A, Olofsen E, Göpfert C, Blood J, Wieditz J, Kharasch ED. Morphine and Hydromorphone Effects, Side Effects, and Variability: A Crossover Study in Human Volunteers. Anesthesiology 2023; 139:16-34. [PMID: 37014986 PMCID: PMC10517626 DOI: 10.1097/aln.0000000000004567] [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] [Indexed: 04/06/2023]
Abstract
BACKGROUND Balancing between opioid analgesia and respiratory depression continues to challenge clinicians in perioperative, emergency department, and other acute care settings. Morphine and hydromorphone are postoperative analgesic standards. Nevertheless, their comparative effects and side effects, timing, and respective variabilities remain poorly understood. This study tested the hypothesis that IV morphine and hydromorphone differ in onset, magnitude, duration, and variability of analgesic and ventilatory effects. METHODS The authors conducted a randomized crossover study in healthy volunteers. Forty-two subjects received a 2-h IV infusion of hydromorphone (0.05 mg/kg) or morphine (0.2 mg/kg) 1 to 2 weeks apart. The authors measured arterial opioid concentrations, analgesia in response to heat pain (maximally tolerated temperature, and verbal analog pain scores at discrete preset temperatures to determine half-maximum temperature effect), dark-adapted pupil diameter and miosis, end-expired carbon dioxide, and respiratory rate for 12 h after dosing. RESULTS For morphine and hydromorphone, respectively, maximum miosis was less (3.9 [3.4 to 4.2] vs. 4.6 mm [4.0 to 5.0], P < 0.001; median and 25 to 75% quantiles) and occurred later (3.1 ± 0.9 vs. 2.3 ± 0.7 h after infusion start, P < 0.001; mean ± SD); maximum tolerated temperature was less (49 ± 2 vs. 50 ± 2°C, P < 0.001); verbal pain scores at end-infusion at the most informative stimulus (48.2°C) were 82 ± 4 and 59 ± 3 (P < 0.001); maximum end-expired CO2 was 47 (45 to 50) and 48 mmHg (46 to 51; P = 0.007) and occurred later (5.5 ± 2.8 vs. 3.0 ± 1.5 h after infusion start, P < 0.001); and respiratory nadir was 9 ± 1 and 11 ± 2 breaths/min (P < 0.001), and occurred at similar times. The area under the temperature tolerance-time curve was less for morphine (1.8 [0.0 to 4.4]) than hydromorphone (5.4°C-h [1.6 to 12.1] P < 0.001). Interindividual variability in clinical effects did not differ between opioids. CONCLUSIONS For morphine compared to hydromorphone, analgesia and analgesia relative to respiratory depression were less, onset of miosis and respiratory depression was later, and duration of respiratory depression was longer. For each opioid, timing of the various clinical effects was not coincident. Results may enable more rational opioid selection, and suggest hydromorphone may have a better clinical profile. EDITOR’S PERSPECTIVE
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Affiliation(s)
- Konrad Meissner
- Klinik für Anästhesiologie, Universitätsmedizin Göttingen, Germany
- Department of Anaesthesiology, Leiden University Medical Center, The Netherlands
- Department of Anesthesiology, Washington University in St. Louis, St. Louis MO, USA
| | - Albert Dahan
- Department of Anaesthesiology, Leiden University Medical Center, The Netherlands
| | - Erik Olofsen
- Department of Anaesthesiology, Leiden University Medical Center, The Netherlands
| | - Christine Göpfert
- Department of Anesthesiology, Washington University in St. Louis, St. Louis MO, USA
| | - Jane Blood
- Department of Anesthesiology, Washington University in St. Louis, St. Louis MO, USA
| | - Johannes Wieditz
- Klinik für Anästhesiologie, Universitätsmedizin Göttingen, Germany
- Department of Medical Statistics, Universitätsmedizin Göttingen, Germany
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Karbownik A, Szkutnik-Fiedler D, Grabowski T, Wolc A, Stanisławiak-Rudowicz J, Jaźwiec R, Grześkowiak E, Szałek E. Pharmacokinetic Drug Interaction Study of Sorafenib and Morphine in Rats. Pharmaceutics 2021; 13:pharmaceutics13122172. [PMID: 34959453 PMCID: PMC8707786 DOI: 10.3390/pharmaceutics13122172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/09/2021] [Accepted: 12/15/2021] [Indexed: 12/02/2022] Open
Abstract
A combination of the tyrosine kinase inhibitor—sorafenib—and the opioid analgesic—morphine—can be found in the treatment of cancer patients. Since both are substrates of P-glycoprotein (P-gp), and sorafenib is also an inhibitor of P-gp, their co-administration may affect their pharmacokinetics, and thus the safety and efficacy of cancer therapy. Therefore, the aim of this study was to evaluate the potential pharmacokinetic drug–drug interactions between sorafenib and morphine using an animal model. The rats were divided into three groups that Received: sorafenib and morphine (ISOR+MF), sorafenib (IISOR), and morphine (IIIMF). Morphine caused a significant increase in maximum plasma concentrations (Cmax) and the area under the plasma concentration–time curves (AUC0–t, and AUC0–∞) of sorafenib by 108.3 (p = 0.003), 55.9 (p = 0.0115), and 62.7% (p = 0.0115), respectively. Also, the Cmax and AUC0–t of its active metabolite—sorafenib N-oxide—was significantly increased in the presence of morphine (p = 0.0022 and p = 0.0268, respectively). Sorafenib, in turn, caused a significant increase in the Cmax of morphine (by 0.5-fold, p = 0.0018). Moreover, in the presence of sorafenib the Cmax, AUC0–t, and AUC0–∞ of the morphine metabolite M3G increased by 112.62 (p < 0.0001), 46.82 (p = 0.0124), and 46.78% (p = 0.0121), respectively. Observed changes in sorafenib and morphine may be of clinical significance. The increased exposure to both drugs may improve the response to therapy in cancer patients, but on the other hand, increase the risk of adverse effects.
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Affiliation(s)
- Agnieszka Karbownik
- Department of Clinical Pharmacy and Biopharmacy, Poznań University of Medical Sciences, 14 Św. Marii Magdaleny Str., 61-861 Poznań, Poland; (A.K.); (J.S.-R.); (E.G.); (E.S.)
| | - Danuta Szkutnik-Fiedler
- Department of Clinical Pharmacy and Biopharmacy, Poznań University of Medical Sciences, 14 Św. Marii Magdaleny Str., 61-861 Poznań, Poland; (A.K.); (J.S.-R.); (E.G.); (E.S.)
- Correspondence: ; Tel.: +48-6166-87865
| | - Tomasz Grabowski
- Preclinical Development, Polpharma Biologics SA, Trzy Lipy 3, 80-172 Gdańsk, Poland;
| | - Anna Wolc
- Department of Animal Science, Iowa State University, 239E Kildee Hall, Ames, IA 50011, USA;
- Research and Development, Hy-Line International, 2583 240th Street, Dallas Center, IA 50063, USA
| | - Joanna Stanisławiak-Rudowicz
- Department of Clinical Pharmacy and Biopharmacy, Poznań University of Medical Sciences, 14 Św. Marii Magdaleny Str., 61-861 Poznań, Poland; (A.K.); (J.S.-R.); (E.G.); (E.S.)
- Department of Gynecological Oncology, University Hospital of Lord’s Transfiguration, Poznań University of Medical Sciences, 84/86 Szamarzewskiego Str., 60-101 Poznań, Poland
| | - Radosław Jaźwiec
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics PAS, Polish Academy of Sciences, 5A Pawińskiego Str., 02-106 Warsaw, Poland;
| | - Edmund Grześkowiak
- Department of Clinical Pharmacy and Biopharmacy, Poznań University of Medical Sciences, 14 Św. Marii Magdaleny Str., 61-861 Poznań, Poland; (A.K.); (J.S.-R.); (E.G.); (E.S.)
| | - Edyta Szałek
- Department of Clinical Pharmacy and Biopharmacy, Poznań University of Medical Sciences, 14 Św. Marii Magdaleny Str., 61-861 Poznań, Poland; (A.K.); (J.S.-R.); (E.G.); (E.S.)
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Loughren MJ, Kharasch ED, Kelton-Rehkopf MC, Syrjala KL, Shen DD. Influence of St. John's Wort on Intravenous Fentanyl Pharmacokinetics, Pharmacodynamics, and Clinical Effects: A Randomized Clinical Trial. Anesthesiology 2020; 132:491-503. [PMID: 31794512 PMCID: PMC7029805 DOI: 10.1097/aln.0000000000003065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Patients often use complementary and alternative herbal medicines, hence, potential exists for adverse herb-drug interactions. Fentanyl is metabolized by hepatic CYP3A4 and considered transported by blood-brain barrier P-glycoprotein. Both disposition processes could be upregulated by the herbal St. John's wort. This investigation evaluated effects of St. John's wort on fixed-dose and apparent steady-state IV fentanyl pharmacokinetics, pharmacodynamics, and clinical effects. METHODS Healthy volunteers received a fentanyl fixed-dose infusion and an individually tailored target controlled infusion on separate days, before and after 30-day St. John's wort (300 mg thrice daily; n = 8) or placebo control (n = 8) in a randomized parallel-group design. Fentanyl plasma concentrations, pupil diameter, analgesic response to experimental pain (cold pressor), subjective side effects, and cognitive effects were measured. Plasma fentanyl concentrations and changes in pupil diameter were subjected to pharmacokinetic-pharmacodynamic modeling. RESULTS St. John's wort did not alter fentanyl pharmacokinetics. Clearance (l/min) before and after St. John's wort (1.13 ± 0.29 and 1.24 ± 0.26, respectively) or placebo (0.96 ± 0.28 and 1.12 ± 0.27, respectively) were not different. St. John's wort also did not affect fentanyl pharmacodynamics as measured by pupil constriction after fixed-dose and tailored fentanyl infusions. EC50 (ng/ml) was 1.1 ± 0.7 and 1.4 ± 0.9 before and after St. John's wort versus 1.2 ± 0.8 and 1.4 ± 1.7 before and after placebo. Effect site equilibration time, T½,ke0 (min), was 12.8 ± 5.3 and 11.3 ± 6.4 before and after St. John's wort versus 11.4 ± 6.4 and 11.1 ± 5.6 before and after placebo. St. John's wort had no influence on analgesia, cognitive performance, or somatic cognitive-affective effects of fentanyl. CONCLUSIONS St. John's wort did not alter fentanyl pharmacokinetics, pharmacodynamics or clinical effects, suggesting no effect on hepatic clearance or blood-brain barrier efflux. Patients taking St. John's wort will likely not respond differently to IV fentanyl for anesthesia or analgesia.
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Affiliation(s)
- Michael J Loughren
- From the Department of Anesthesia and Operative Services, Madigan Army Medical Center, Tacoma, Washington (M.J.L.) the Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina (E.D.K) the Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (M.J.L., D.D.S.) the Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington (M.C.K.-R., K.S., D.D.S.)
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Tylleskar I, Skulberg AK, Skarra S, Nilsen T, Dale O. Pharmacodynamics and arteriovenous difference of intravenous naloxone in healthy volunteers exposed to remifentanil. Eur J Clin Pharmacol 2018; 74:1547-1553. [PMID: 30143830 DOI: 10.1007/s00228-018-2545-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 08/16/2018] [Indexed: 01/03/2023]
Abstract
PURPOSE Pharmacodynamic studies of naloxone require opioid agonism. Steady state condition may be achieved by remifentanil TCI (target controlled infusion). Opioid agonism can be measured by pupillometry. It is not known whether there are arteriovenous concentration differences for naloxone. The aim was thus to further develop a model for studying pharmacokinetic/pharmacodynamic aspects of naloxone and to explore whether a significant arteriovenous concentration difference for naloxone in humans was present. METHODS Relevant authorities approved this study. Healthy volunteers (n = 12) were given 1.0 mg intravenous (IV) naloxone after steady state opioid agonism was obtained by TCI of remifentanil (1.3 ng/ml). Opioid effect was measured by pupillometry. Arterial and venous samples were collected simultaneously before and for 2 h after naloxone administration for quantification of naloxone and remifentanil. RESULTS Arterial remifentanil was in steady state at 12 min. One milligram IV naloxone reversed the effect of remifentanil to 93% of pre-opioid pupil-size within 4 min. The estimated duration of antagonism was 118 min. At that time, the concentration of naloxone was 0.51 ng/ml. The time course of arterial and venous serum concentrations for naloxone was similar, although arterial AUC (area under the curve) was slightly lower (94%) than the venous AUC (p = 0.03). There were no serious adverse events. CONCLUSION Onset of reversal by IV naloxone was rapid and lasted 118 min. The minimum effective concentration was 0.5 ng/ml. Using TCI remifentanil to obtain a steady-state opioid agonism may be a useful tool to compare new naloxone products.
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Affiliation(s)
- Ida Tylleskar
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway.,Clinic of Emergency Medicine and Prehospital Care, St. Olavs hospital, Trondheim University Hospital, Trondheim, Norway
| | - Arne Kristian Skulberg
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway.,Division of Emergencies and Critical Care, Department of Anaesthesiology, Oslo University Hospital, Oslo, Norway
| | - Sissel Skarra
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway
| | - Turid Nilsen
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway
| | - Ola Dale
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway. .,Department of Research and Development, St. Olavs hospital, Trondheim University Hospital, Trondheim, Norway.
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Chaves C, Remiao F, Cisternino S, Decleves X. Opioids and the Blood-Brain Barrier: A Dynamic Interaction with Consequences on Drug Disposition in Brain. Curr Neuropharmacol 2018; 15:1156-1173. [PMID: 28474563 PMCID: PMC5725546 DOI: 10.2174/1570159x15666170504095823] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 04/04/2017] [Accepted: 04/25/2017] [Indexed: 12/28/2022] Open
Abstract
Background: Opioids are widely used in pain management, acting via opioid receptors and/or Toll-like receptors (TLR) present at the central nervous system (CNS). At the blood-brain barrier (BBB), several influx and efflux transporters, such as the ATP-binding cassette (ABC) P-glycoprotein (P-gp, ABCB1), Breast Cancer Resistance Protein (BCRP, ABCG2) and multidrug resistance-associated proteins (MRP, ABCC) transporters, and solute carrier transporters (SLC), are responsible for the transport of xenobiotics from the brain into the bloodstream or vice versa. Objective: ABC transporters export several clinically employed opioids, altering their neuro- pharmacokinetics and CNS effects. In this review, we explore the interactions between opioids and ABC transporters, and decipher the molecular mechanisms by which opioids can modify their expression at the BBB. Results: P-gp is largely implicated in the brain-to-blood efflux of opioids, namely morphine and oxycodone. Long-term ex-posure to morphine and oxycodone has proven to up-regulate the expression of ABC transporters, such as P-gp, BCRP and MRPs, at the BBB, which may lead to increased tolerance to the antinociceptive effects of such drugs. Recent studies uncov-er two mechanisms by which morphine may up-regulate P-gp and BCRP at the BBB: 1) via a glutamate, NMDA-receptor and COX-2 signaling cascade, and 2) via TLR4 activation, subsequent development of neuro- inflammation, and activation of NF-κB, presumably via glial cells. Conclusion: The BBB-opioid interaction can culminate in bilateral consequences, since ABC transporters condition the brain disposition of opioids, while opioids also affect the expression of ABC transporters at the BBB, which may result in increased CNS drug pharmacoresistance.
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Affiliation(s)
- Catarina Chaves
- Variabilite de Reponse Aux Psychotropes, INSERM, U1144, 75006 Paris, France.,Universite Paris Descartes, UMR-S 1144, Paris, F-75006, France.,Universite Paris Diderot, UMR-S 1144, Paris, F-75013, France.,REQUIMTE, Laboratorio de Toxicologia, Departamento de Ciencias Biologicas, Faculdade de Farmacia, Universidade do Porto, Porto, Portugal
| | - Fernando Remiao
- REQUIMTE, Laboratorio de Toxicologia, Departamento de Ciencias Biologicas, Faculdade de Farmacia, Universidade do Porto, Porto, Portugal
| | - Salvatore Cisternino
- Variabilite de Reponse Aux Psychotropes, INSERM, U1144, 75006 Paris, France.,Universite Paris Descartes, UMR-S 1144, Paris, F-75006, France.,Universite Paris Diderot, UMR-S 1144, Paris, F-75013, France.,Assistance Publique Hopitaux de Paris, AP-HP, Paris, France
| | - Xavier Decleves
- Variabilite de Reponse Aux Psychotropes, INSERM, U1144, 75006 Paris, France.,Universite Paris Descartes, UMR-S 1144, Paris, F-75006, France.,Universite Paris Diderot, UMR-S 1144, Paris, F-75013, France.,Assistance Publique Hopitaux de Paris, AP-HP, Paris, France
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8
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Kharasch ED. Current Concepts in Methadone Metabolism and Transport. Clin Pharmacol Drug Dev 2018; 6:125-134. [PMID: 28263461 DOI: 10.1002/cpdd.326] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 11/07/2016] [Indexed: 12/17/2022]
Abstract
Methadone is a cornerstone therapy for opioid addiction and a public health strategy for HIV/AIDS and hepatitis C reduction. Methadone is also used for acute and chronic pain. As use for chronic pain has grown, so too have adverse events. Constitutive and acquired (drug interactions) inter- and intraindividual variability in methadone pharmacokinetics and pharmacodynamics confounds reliable clinical use. Identification of enzymes and transporters responsible for methadone disposition has been a long-sought ideal. Initial in vitro studies identified CYP3A4 as metabolizing methadone. Subsequently, by extrapolation, CYP3A4 was long assumed to be responsible for clinical methadone disposition. However, CYP2B6 is also a major catalyst of methadone metabolism in vitro. It has now been unequivocally established that CYP2B6, not CYP3A4, is the principal determinant of methadone metabolism, clearance, elimination, and plasma concentrations in humans. Methadone disposition is susceptible to inductive and inhibitory drug interactions. CYP2B6 genetics also influences methadone metabolism and clearance, which were diminished in CYP2B6*6 carriers and increased in CYP2B6*4 carriers. CYP2B6 genetics can explain, in part, interindividual variability in methadone metabolism and clearance. Thus, both constitutive variability due to CYP2B6 genetics, and CYP2B6-mediated drug interactions, can alter methadone disposition, clinical effect, and drug safety. Methadone is not a substrate for major influx or efflux transporters.
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Affiliation(s)
- Evan D Kharasch
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA.,Department of Biochemistry and Biophysics, Washington University in St. Louis, St. Louis, MO, USA.,The Center for Clinical Pharmacology, St. Louis College of Pharmacy and Washington University in St. Louis School of Medicine, St. Louis, MO, USA
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9
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Pharmacokinetics and -dynamics of intramuscular and intranasal naloxone: an explorative study in healthy volunteers. Eur J Clin Pharmacol 2018; 74:873-883. [PMID: 29568976 DOI: 10.1007/s00228-018-2443-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 03/12/2018] [Indexed: 12/12/2022]
Abstract
PURPOSE This study aimed to develop a model for pharmacodynamic and pharmacokinetic studies of naloxone antagonism under steady-state opioid agonism and to compare a high-concentration/low-volume intranasal naloxone formulation 8 mg/ml to intramuscular 0.8 mg. METHODS Two-way crossover in 12 healthy volunteers receiving naloxone while receiving remifentanil by a target-controlled infusion for 102 min. The group were subdivided into three different doses of remifentanil. Blood samples for serum naloxone concentrations, pupillometry and heat pain threshold were measured. RESULTS The relative bioavailability of intranasal to intramuscular naloxone was 0.75. Pupillometry showed difference in antagonism; the effect was significant in the data set as a whole (p < 0.001) and in all three subgroups (p < 0.02-p < 0.001). Heat pain threshold showed no statistical difference. CONCLUSIONS A target-controlled infusion of remifentanil provides good conditions for studying the pharmacodynamics of naloxone, and pupillometry was a better modality than heat pain threshold. Intranasal naloxone 0.8 mg is inferior for a similar dose intramuscular. Our design may help to bridge the gap between studies in healthy volunteers and the patient population in need of naloxone for opioid overdose. TRIAL REGISTRATION clinicaltrials.gov : NCT02307721.
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Bartels K, Meissner K. Morphine and the blood-brain barrier: diffusion, uptake, or efflux? Can J Anaesth 2017; 64:997-1001. [PMID: 28721688 DOI: 10.1007/s12630-017-0932-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 06/20/2017] [Accepted: 07/05/2017] [Indexed: 01/16/2023] Open
Affiliation(s)
- Karsten Bartels
- Department of Anesthesiology, University of Colorado Denver, 12401 E. 17th Avenue, Leprino Office Building, 7th Floor, MS B-113, Aurora, CO, 80045, USA.
| | - Konrad Meissner
- Klinik für Anästhesiologie, Universitätsmedizin Greifswald, Greifswald, Germany
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An observational study examining the effects of a surgically induced inflammatory response on the distribution of morphine and its metabolites into cerebrospinal fluid. Can J Anaesth 2017; 64:1009-1022. [PMID: 28710563 DOI: 10.1007/s12630-017-0933-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 05/25/2017] [Accepted: 07/05/2017] [Indexed: 01/11/2023] Open
Abstract
PURPOSE Morphine is administered intravenously for pain management in the perioperative period. The effect of the inflammatory response to surgery on morphine distribution across the blood-brain barrier (BBB) in humans was investigated. We hypothesized that a graded surgically induced, systemic inflammatory response alters cerebrospinal fluid (CSF) levels of morphine, morphine-3-glucuronide (M3G), and morphine-6-glucuronide (M6G) through a temporary reduction in BBB drug efflux transporter function. METHODS We conducted a prospective pharmacokinetic study of the plasma and CSF distribution of the P-glycoprotein (PGP) substrate morphine in 33 patients undergoing open thoracic (n = 18) or endovascular (n = 15) aortic aneurysm repair. Morphine was administered with induction of anesthesia and in the intensive care unit. Plasma and CSF concentrations of interleukin (IL)-6, morphine, M3G, M6G, and albumin were measured prior to surgery (baseline), during surgery, and postoperatively every six hours until removal of the CSF drain. The area under the curve (AUC) was determined for plasma and CSF IL-6, morphine, M3G, and M6G concentrations vs time. The primary endpoint measures were the correlations between the morphine, M6G, and M3G AUC CSF/plasma ratios and systemic inflammation as quantified by the time-normalized IL-6 exposure, which was calculated for each individual by dividing the total exposure (AUC) by time (t). A Bonferroni corrected P < 0.017 indicated a significant correlation. RESULTS Plasma and CSF IL-6 concentrations increased postoperatively. The median [interquartile range] IL-6 exposures were significantly higher in the open vs endovascular surgical group for plasma (105 [40-256] pg·mL-1 vs 29 [16-70] pg·mL-1, respectively; P = 0.013) and CSF (79 [26-133] pg·mL-1 vs 16 [9-80] pg·mL-1, respectively; P = 0.013). For the primary endpoint, the plasma IL-6 AUC/t did not correlate with the CSF accumulation of morphine (r = -0.009; P = 0.96) or M3G (r = 0.37; P = 0.04) when corrected for surgical procedure, age, and sex. There were insufficient data on CSF concentration to complete the primary analysis for M6G. CONCLUSION Morphine distribution into the CSF was not significantly altered in patients undergoing thoracic aortic aneurysm repair. This suggests that BBB PGP function may not be affected by the perioperative inflammatory response. TRIAL REGISTRATION www.clinicaltrials.gov , NCT 00878371. Registered 7 April 2009.
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Hook MA, Woller SA, Bancroft E, Aceves M, Funk MK, Hartman J, Garraway SM. Neurobiological Effects of Morphine after Spinal Cord Injury. J Neurotrauma 2016; 34:632-644. [PMID: 27762659 DOI: 10.1089/neu.2016.4507] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Opioids and non-steroidal anti-inflammatory drugs are used commonly to manage pain in the early phase of spinal cord injury (SCI). Despite its analgesic efficacy, however, our studies suggest that intrathecal morphine undermines locomotor recovery and increases lesion size in a rodent model of SCI. Similarly, intravenous (IV) morphine attenuates locomotor recovery. The current study explores whether IV morphine also increases lesion size after a spinal contusion (T12) injury and quantifies the cell types that are affected by early opioid administration. Using an experimenter-administered escalating dose of IV morphine across the first seven days post-injury, we quantified the expression of neuron, astrocyte, and microglial markers at the injury site. SCI decreased NeuN expression relative to shams. In subjects with SCI treated with IV morphine, virtually no NeuN+ cells remained across the rostral-caudal extent of the lesion. Further, whereas SCI per se increased the expression of astrocyte and microglial markers (glial fibrillary acidic protein and OX-42, respectively), morphine treatment decreased the expression of these markers. These cellular changes were accompanied by attenuation of locomotor recovery (Basso, Beattie, Bresnahan scores), decreased weight gain, and the development of opioid-induced hyperalgesia (increased tactile reactivity) in morphine-treated subjects. These data suggest that morphine use is contraindicated in the acute phase of a spinal injury. Faced with a lifetime of intractable pain, however, simply removing any effective analgesic for the management of SCI pain is not an ideal option. Instead, these data underscore the critical need for further understanding of the molecular pathways engaged by conventional medications within the pathophysiological context of an injury.
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Affiliation(s)
- Michelle A Hook
- 1 Texas A&M University Institute for Neuroscience, Texas A&M University , College Station, Texas.,2 Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center , Bryan, Texas
| | - Sarah A Woller
- 3 Department of Anesthesiology, University of California , San Diego, California
| | - Eric Bancroft
- 2 Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center , Bryan, Texas
| | - Miriam Aceves
- 1 Texas A&M University Institute for Neuroscience, Texas A&M University , College Station, Texas.,2 Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center , Bryan, Texas
| | - Mary Katherine Funk
- 2 Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center , Bryan, Texas
| | - John Hartman
- 2 Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center , Bryan, Texas
| | - Sandra M Garraway
- 4 Department of Physiology, Emory University School of Medicine , Atlanta, Georgia
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Abstract
This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants).
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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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14
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Rivera-Burgos D, Sarkar U, Lever AR, Avram MJ, Coppeta JR, Wishnok JS, Borenstein JT, Tannenbaum SR. Glucocorticoid Clearance and Metabolite Profiling in an In Vitro Human Airway Epithelium Lung Model. ACTA ACUST UNITED AC 2015; 44:220-6. [PMID: 26586376 DOI: 10.1124/dmd.115.066365] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 11/18/2015] [Indexed: 12/18/2022]
Abstract
The emergence of microphysiologic epithelial lung models using human cells in a physiologically relevant microenvironment has the potential to be a powerful tool for preclinical drug development and to improve predictive power regarding in vivo drug clearance. In this study, an in vitro model of the airway comprising human primary lung epithelial cells cultured in a microfluidic platform was used to establish a physiologic state and to observe metabolic changes as a function of glucocorticoid exposure. Evaluation of mucus production rate and barrier function, along with lung-specific markers, demonstrated that the lungs maintained a differentiated phenotype. Initial concentrations of 100 nM hydrocortisone (HC) and 30 nM cortisone (C) were used to evaluate drug clearance and metabolite production. Measurements made using ultra-high-performance liquid chromatography and high-mass-accuracy mass spectrometry indicated that HC metabolism resulted in the production of C and dihydrocortisone (diHC). When the airway model was exposed to C, diHC was identified; however, no conversion to HC was observed. Multicompartmental modeling was used to characterize the lung bioreactor data, and pharmacokinetic parameters, including elimination clearance and elimination half-life, were estimated. Polymerse chain reaction data confirmed overexpression of 11-β hydroxysteroid dehydrogenase 2 (11βHSD2) over 11βHSD1, which is biologically relevant to human lung. Faster metabolism was observed relative to a static model on elevated rates of C and diHC formation. Overall, our results demonstrate that this lung airway model has been successfully developed and could interact with other human tissues in vitro to better predict in vivo drug behavior.
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Affiliation(s)
- Dinelia Rivera-Burgos
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - Ujjal Sarkar
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - Amanda R Lever
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - Michael J Avram
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - Jonathan R Coppeta
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - John S Wishnok
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - Jeffrey T Borenstein
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
| | - Steven R Tannenbaum
- Department of Biological Engineering (D.R.B., U.S., J.S.W., S.R.T.), and Department of Chemistry (S.R.T.), Massachusetts Institute of Technology, and The Charles Stark Draper Laboratory (A.R.L., J.R.C., J.T.B.), Cambridge, Massachusetts; and Northwestern University, Feinberg School of Medicine, Chicago, Illinois (M.J.A.)
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Mikus G, Klimas R. Relative contribution of morphine and morphine-6-glucuronide to the analgesic effect after morphine administration. Br J Anaesth 2015; 114:1007. [DOI: 10.1093/bja/aev132] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Gharavi R, Hedrich W, Wang H, Hassan HE. Transporter-Mediated Disposition of Opioids: Implications for Clinical Drug Interactions. Pharm Res 2015; 32:2477-502. [PMID: 25972096 DOI: 10.1007/s11095-015-1711-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 05/06/2015] [Indexed: 01/08/2023]
Abstract
Opioid-related deaths, abuse, and drug interactions are growing epidemic problems that have medical, social, and economic implications. Drug transporters play a major role in the disposition of many drugs, including opioids; hence they can modulate their pharmacokinetics, pharmacodynamics and their associated drug-drug interactions (DDIs). Our understanding of the interaction of transporters with many therapeutic agents is improving; however, investigating such interactions with opioids is progressing relatively slowly despite the alarming number of opioids-mediated DDIs that may be related to transporters. This review presents a comprehensive report of the current literature relating to opioids and their drug transporter interactions. Additionally, it highlights the emergence of transporters that are yet to be fully identified but may play prominent roles in the disposition of opioids, the growing interest in transporter genomics for opioids, and the potential implications of opioid-drug transporter interactions for cancer treatments. A better understanding of drug transporters interactions with opioids will provide greater insight into potential clinical DDIs and could help improve opioids safety and efficacy.
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Affiliation(s)
- Robert Gharavi
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 N Pine Street, Rooms: N525 (Office), Baltimore, Maryland, 21201, USA
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Advancing novel anesthetics: pharmacodynamic and pharmacokinetic studies of cyclopropyl-methoxycarbonyl metomidate in dogs. Anesthesiology 2015; 121:1203-16. [PMID: 25170571 DOI: 10.1097/aln.0000000000000416] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Cyclopropyl-methoxycarbonyl metomidate (CPMM, also known as ABP-700) is a second-generation "soft" (i.e., metabolically labile) etomidate analogue. The purpose of this study was to characterize CPMM's pharmacology in beagle dogs in preparation for potential first in human phase 1 clinical trials. METHODS CPMM's and etomidate's hypnotic activity and duration of action were assessed using loss of righting reflex and anesthesia score assays in three or four dogs. Their pharmacokinetics were defined after single bolus administration and single bolus followed by 2-h infusion. Adrenocortical recovery times after single bolus followed by 2-h infusion of CPMM, propofol, etomidate, and vehicle were measured using an adrenocorticotropic hormone stimulation test. RESULTS Compared with etomidate, CPMM was half as potent as a hypnotic (ED50 approximately 0.8 mg/kg), was more rapidly metabolized, and had a shorter duration of sedative-hypnotic action. Recovery times after CPMM administration were also independent of infusion duration. After hypnotic infusion, adrenocorticotropic hormone-stimulated plasma cortisol concentrations were 4- to 27-fold higher in dogs that received CPMM versus etomidate. Adrenocortical recovery was faster in dogs after CPMM infusion versus etomidate infusion (half-time: 215 vs. 1,623 min, respectively). Adrenocortical responsiveness assessed 90 min after CPMM infusion was not significantly different from that after propofol infusion. CONCLUSION The studies in dogs confirm that CPMM has hypnotic and adrenocortical recovery profiles that are superior than those of etomidate, supporting the continued development of CPMM as a clinical sedative-hypnotic to be used as a single bolus and by continuous infusion to induce and maintain general anesthesia or procedural sedation.
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Meissner K, Blood J, Francis AM, Yermolenka V, Kharasch ED. Cyclosporine-inhibitable cerebral drug transport does not influence clinical methadone pharmacodynamics. Anesthesiology 2015; 121:1281-91. [PMID: 25072223 DOI: 10.1097/aln.0000000000000391] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Interindividual variability and drug interaction studies suggest that blood-brain barrier drug transporters mediate human methadone brain biodistribution. In vitro and animal studies suggest that methadone is a substrate for the efflux transporter P-glycoprotein, and that P-glycoprotein-mediated transport influences brain access and pharmacologic effect. This investigation tested whether methadone is a transporter substrate in humans [corrected]. METHODS Healthy volunteers received oral (N=16) or IV (N=12) methadone in different crossover protocols after nothing (control) or the validated P-glycoprotein inhibitor cyclosporine (4.5 mg/kg orally twice daily for 4 days, or 5 mg/kg IV over 2 h). Plasma and urine methadone and metabolite concentrations were measured by mass spectrometry. Methadone effects were measured by miosis and thermal analgesia (maximally tolerated temperature and verbal analog scale rating of discreet temperatures). RESULTS Cyclosporine marginally but significantly decreased methadone plasma concentrations and apparent oral clearance, but had no effect on methadone renal clearance or on hepatic N-demethylation. Cyclosporine had no effect on miosis or on R-methadone concentration-miosis relationships after either oral or IV methadone. Peak miosis was similar in controls and cyclosporine-treated subjects after oral methadone (1.4±0.4 and 1.3±0.5 mm/mg, respectively) and IV methadone (3.1±1.0 and 3.2±0.8 mm, respectively). Methadone increased maximally tolerated temperature, but analgesia testing was confounded by cyclosporine-related pain. CONCLUSIONS Cyclosporine did not affect methadone pharmacodynamics. This result does not support a role for cyclosporine-inhibitable transporters mediating methadone brain access and biodistribution.
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Affiliation(s)
- Konrad Meissner
- From the Department of Anesthesiology, Universitätsmedizin Greifswald, Greifswald, Germany (K.M.); and Departments of Anesthesiology (K.M., J.B., A.M.F., V.Y., E.D.K.) and of Biochemistry and Molecular Biophysics (E.D.K.), Washington University in St. Louis, St. Louis, Missouri
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