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Siebenga PS, van Amerongen G, Okkerse P, Denney WS, Dua P, Butt RP, Hay JL, Groeneveld GJ. Reproducibility of a battery of human evoked pain models to detect pharmacological effects of analgesic drugs. Eur J Pain 2019; 23:1129-1140. [PMID: 30793411 PMCID: PMC6618124 DOI: 10.1002/ejp.1379] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 02/01/2019] [Accepted: 02/17/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND Although reproducibility is considered essential for any method used in scientific research, it is investigated only rarely; thus, strikingly little has been published regarding the reproducibility of evoked pain models involving human subjects. Here, we studied the reproducibility of a battery of evoked pain models for demonstrating the analgesic effects of two analgesic compounds. METHODS A total of 81 healthy subjects participated in four studies involving a battery of evoked pain tests in which mechanical, thermal and electrical stimuli were used to measure pain detection and tolerance thresholds. Pharmacodynamic outcome variables were analysed using a mixed model analysis of variance, and a coefficient of variation was calculated by dividing the standard deviation by the least squares means. RESULTS A total of 76 subjects completed the studies. After being administered pregabalin, the subjects' pain tolerance thresholds in the cold pressor and pressure stimulation tests were significantly increased compared to the placebo group. Moreover, the heat pain detection threshold in UVB-irradiated skin was significantly increased in subjects who were administered ibuprofen compared to the placebo group. Variation among all evoked pain tests ranged from 2.2% to 30.6%. CONCLUSIONS Four studies using a similar design showed reproducibility with respect to the included evoked pain models. The relatively high consistency and reproducibility of two analgesics at doses known to be effective in treating clinically relevant pain supports the validity of using this pain test battery to investigate the analgesic activity and determine the active dosage of putative analgesic compounds in early clinical development. SIGNIFICANCE The consistency and reproducibility of measuring the profile of an analgesic at clinically relevant doses illustrates that this pain test battery is a valid tool for demonstrating the analgesic activity of a test compound and for determining the optimal active dose in early clinical drug development.
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Affiliation(s)
| | | | | | - William S. Denney
- Pfizer Inc.CambridgeMassachusetts
- Present address:
Human Predictions LLCCambridgeMassachusetts
| | | | | | | | - Geert J. Groeneveld
- Centre for Human Drug ResearchLeidenThe Netherlands
- Leiden University Medical CenterLeidenThe Netherlands
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Gurrell R, Gorman D, Whitlock M, Ogden A, Reynolds DS, DiVentura B, Abou-Khalil B, Gelfand M, Pollard J, Hogan RE, Krauss G, Sperling M, Vazquez B, Wechsler RT, Friedman D, Butt RP, French J. Photosensitive epilepsy. Neurology 2019; 92:e1786-e1795. [DOI: 10.1212/wnl.0000000000007271] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 12/17/2018] [Indexed: 12/13/2022] Open
Abstract
ObjectiveThe objective of this phase 2a study was to assess the activity of PF-06372865, a positive allosteric modulator (PAM) of α2/3/5 subunit-containing GABAA receptors with minimal activity at α1-containing receptors, which are believed to mediate many of the adverse events associated with benzodiazepines, in the epilepsy photosensitivity model as a proof-of-principle of efficacy.MethodsSeven participants with a photoparoxysmal response to intermittent photic stimulation (IPS) at baseline were randomized in a double-blind, 4-period cross-over study examining single doses of 17.5 and 52.5 mg PF-06372865, 2 mg lorazepam (active control), and placebo. Standardized photosensitivity ranges (SPRs) to IPS were recorded at screening, predose, and 1, 2, 4, and 6 hours postdose. The primary endpoint was the average least squares mean change in the SPR in the participant's most sensitive eye condition, across all time points.ResultsBoth doses of PF-06372865 produced a marked and statistically significant mean reduction in SPR compared to placebo, which was similar in degree to lorazepam. There was complete suppression of SPR in 6/7 participants following PF-06372865 or lorazepam administration. PF-06372865 was safe and well-tolerated.ConclusionPF-06372865 demonstrated highly robust efficacy. This demonstrates anticonvulsant activity of a novel α2/3/5-subtype selective GABAA PAM in humans. Further study of the antiepileptic properties of PF-06372865 is warranted.Clinicaltrials.gov identifierNCT02564029.Classification of evidenceThis study provides Class II evidence that for people with a stable photoparoxysmal response to intermittent photic stimulation, PF-06372865 reduces the SPR.
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Gurrell R, Dua P, Feng G, Sudworth M, Whitlock M, Reynolds DS, Butt RP. A randomised, placebo-controlled clinical trial with the α2/3/5 subunit selective GABAA positive allosteric modulator PF-06372865 in patients with chronic low back pain. Pain 2019; 159:1742-1751. [PMID: 29787472 DOI: 10.1097/j.pain.0000000000001267] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effect of PF-06372865, a subtype-selective positive allosteric modulator of the γ-aminobutyric acid type A (GABAA) receptor, on chronic low back pain was investigated in a randomised, placebo- and active-controlled phase 2 clinical trial. The parallel treatment group trial consisted of a 1-week single-blind placebo run in the phase, followed by 4-week double-blind treatment. Patients were randomised to receive either PF-06372865, naproxen, or placebo twice a day for 4 weeks. The primary end point was the numerical rating score of low back pain intensity after 4 weeks of active treatment. Secondary end points included the Roland Morris Disability Questionnaire and the Hopkins Verbal Learning Test-Revised. The trial had predefined decision rules based on the probability that PF-06372865 was better than placebo. The study was stopped at the interim analysis for futility. At this time, a total of 222 patients were randomised and the mean PF-06372865 4-week response on the low back pain intensity was 0.16 units higher (worse) than placebo (90% confidence interval -0.28 to 0.60). There were small, statistically significant reductions in the delayed recall test score with PF-06372865, as measured by Hopkins Verbal Learning Test-Revised. The effects of naproxen were in line with expectations. PF-06372865 was well tolerated. The most common treatment-related adverse events in the PF-06372865 arm were somnolence (5 mild and 4 moderate), dizziness (2 mild and 3 moderate), and nausea (2 mild). Although the reason for the lack of analgesic effect is not completely clear, it may be a result of not achieving sufficient receptor occupancy to drive efficacy.
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Affiliation(s)
- Rachel Gurrell
- Pfizer Inc, Neusentis, Granta Park, Cambridge, United Kingdom
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4
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van Amerongen G, Siebenga PS, Gurrell R, Dua P, Whitlock M, Gorman D, Okkerse P, Hay JL, Butt RP, Groeneveld GJ. Analgesic potential of PF-06372865, an α2/α3/α5 subtype-selective GABA A partial agonist, in humans. Br J Anaesth 2019; 123:e194-e203. [PMID: 30915991 DOI: 10.1016/j.bja.2018.12.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/11/2018] [Accepted: 12/11/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND This study investigated the analgesic effects of two doses (15 and 65 mg) of PF-06372865, a novel α2/α3/α5 gamma-aminobutyric acid A (GABAA) subunit selective partial positive allosteric modulator (PAM), compared with placebo and pregabalin (300 mg) as a positive control. METHODS We performed a randomised placebo-controlled crossover study (NCT02238717) in 20 healthy subjects, using a battery of pain tasks (electrical, pressure, heat, cold and inflammatory pain, including a paradigm of conditioned pain modulation). Pharmacodynamic measurements were performed at baseline and up to 10 h after dose. RESULTS A dose of 15 mg PF-06372865 increased pain tolerance thresholds (PTTs) for pressure pain at a ratio of 1.11 (90% confidence interval [CI]: 1.02, 1.22) compared with placebo. A dose of 65 mg PF-06372865 led to an increase in PTT for the cold pressor at a ratio of 1.17 (90% CI: 1.03, 1.32), and pressure pain task: 1.11 (90% CI: 1.01, 1.21). Pregabalin showed an increase in PTT for pressure pain at a ratio of 1.15 (95% CI: 1.06, 1.26) and cold pressor task: 1.31 (90% CI: 1.16, 1.48). CONCLUSION We conclude that PF-06372865 has analgesic potential at doses that do not induce significant sedation or other intolerable adverse events limiting its clinical use. In addition, the present study established the potential role for this battery of pain tasks as a tool in the development of analgesics with a novel mechanism of action, for the treatment of various pain states including neuropathic pain and to establish proof-of-concept. CLINICAL TRIALS REGISTRATION NCT0223871.
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Affiliation(s)
| | | | | | - Pinky Dua
- Early Clinical Development, Pfizer WRD, Cambridge, UK
| | - Mark Whitlock
- Early Clinical Development, Pfizer WRD, Cambridge, UK
| | - Donal Gorman
- Early Clinical Development, Pfizer WRD, Cambridge, UK
| | - Pieter Okkerse
- Centre for Human Drug Research (CHDR), Leiden, the Netherlands
| | - Justin L Hay
- Centre for Human Drug Research (CHDR), Leiden, the Netherlands
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5
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Nickolls SA, Gurrell R, van Amerongen G, Kammonen J, Cao L, Brown AR, Stead C, Mead A, Watson C, Hsu C, Owen RM, Pike A, Fish RL, Chen L, Qiu R, Morris ED, Feng G, Whitlock M, Gorman D, van Gerven J, Reynolds DS, Dua P, Butt RP. Pharmacology in translation: the preclinical and early clinical profile of the novel α2/3 functionally selective GABA A receptor positive allosteric modulator PF-06372865. Br J Pharmacol 2018; 175:708-725. [PMID: 29214652 DOI: 10.1111/bph.14119] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 10/30/2017] [Accepted: 11/23/2017] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Benzodiazepines, non-selective positive allosteric modulators (PAMs) of GABAA receptors, have significant side effects that limit their clinical utility. As many of these side effects are mediated by the α1 subunit, there has been a concerted effort to develop α2/3 subtype-selective PAMs. EXPERIMENTAL APPROACH In vitro screening assays were used to identify molecules with functional selectivity for receptors containing α2/3 subunits over those containing α1 subunits. In vivo receptor occupancy (RO) was conducted, prior to confirmation of in vivo α2/3 and α1 pharmacology through quantitative EEG (qEEG) beta frequency and zolpidem drug discrimination in rats respectively. PF-06372865 was then progressed to Phase 1 clinical trials. KEY RESULTS PF-06372865 exhibited functional selectivity for those receptors containing α2/3/5 subunits, with significant positive allosteric modulation (90-140%) but negligible activity (≤20%) at GABAA receptors containing α1 subunits. PF-06372865 exhibited concentration-dependent occupancy of GABAA receptors in preclinical species. There was an occupancy-dependent increase in qEEG beta frequency and no generalization to a GABAA α1 cue in the drug-discrimination assay, clearly demonstrating the lack of modulation at the GABAA receptors containing an α1 subtype. In a Phase 1 single ascending dose study in healthy volunteers, evaluation of the pharmacodynamics of PF-06372865 demonstrated a robust increase in saccadic peak velocity (a marker of α2/3 pharmacology), increases in beta frequency qEEG and a slight saturating increase in body sway. CONCLUSIONS AND IMPLICATIONS PF-06372865 has a unique clinical pharmacology profile and a highly predictive translational data package from preclinical species to the clinical setting.
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Affiliation(s)
- Sarah A Nickolls
- Pfizer Inc., Cambridge, UK.,GSK Medicines Research Centre, Stevenage, UK
| | | | | | | | | | | | | | - Andy Mead
- Pfizer Worldwide Research and Development, Groton, CT, USA.,Drug Safety & Metabolism, AstraZeneca, Cambridge, UK
| | - Christine Watson
- Department of Worldwide Medicinal Chemistry, Pfizer Global Research and Development, Sandwich Laboratories, Sandwich, Kent, UK
| | - Cathleen Hsu
- Pfizer Worldwide Research and Development, Groton, CT, USA
| | | | | | | | - Laigao Chen
- Pfizer Worldwide Research and Development, Groton, CT, USA
| | - Ruolun Qiu
- Pfizer Worldwide Research and Development, Groton, CT, USA
| | - Evan D Morris
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
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6
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Loudon P, Siebenga P, Gorman D, Gore K, Dua P, van Amerongen G, Hay JL, Groeneveld GJ, Butt RP. Demonstration of an anti-hyperalgesic effect of a novel pan-Trk inhibitor PF-06273340 in a battery of human evoked pain models. Br J Clin Pharmacol 2017; 84:301-309. [PMID: 29178434 DOI: 10.1111/bcp.13448] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 08/30/2017] [Accepted: 09/23/2017] [Indexed: 02/06/2023] Open
Abstract
AIM Inhibitors of nerve growth factor (NGF) reduce pain in several chronic pain indications. NGF signals through tyrosine kinase receptors of the tropomyosin-related kinase (Trk) family and the unrelated p75 receptor. PF-06273340 is a small molecule inhibitor of Trks A, B and C that reduces pain in nonclinical models, and the present study aimed to investigate the pharmacodynamics of this first-in-class molecule in humans. METHODS A randomized, double-blind, single-dose, placebo- and active-controlled five-period crossover study was conducted in healthy human subjects (NCT02260947). Subjects received five treatments: PF-06273340 50 mg, PF-06273340 400 mg, pregabalin 300 mg, ibuprofen 600 mg and placebo. The five primary endpoints were the pain detection threshold for the thermal pain tests and the pain tolerance threshold for the cold pressor, electrical stair and pressure pain tests. The trial had predefined decision rules based on 95% confidence that the PF-06273340 effect was better than that of placebo. RESULTS Twenty subjects entered the study, with 18 completing all five periods. The high dose of PF-06273340 met the decision rules on the ultraviolet (UV) B skin thermal pain endpoint [least squares (LS) mean vs. placebo: 1.13, 95% confidence interval: 0.64-1.61], but not on the other four primary endpoints. The low dose did not meet the decision criteria for any of the five primary endpoints. Pregabalin (cold pressor and electrical stair tests) and ibuprofen (UVB thermal pain) showed significant analgesic effects on expected endpoints. CONCLUSIONS The study demonstrated, for the first time, the translation of nonclinical effects into man in an inflammatory pain analgesic pharmacodynamic endpoint using a pan-Trk inhibitor.
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Affiliation(s)
- Peter Loudon
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
| | - Pieter Siebenga
- Centre for Human Drug Research, Zernikedreef, 8,2333 CL, Leiden, the Netherlands
| | - Donal Gorman
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
| | - Katrina Gore
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
| | - Pinky Dua
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
| | - Guido van Amerongen
- Centre for Human Drug Research, Zernikedreef, 8,2333 CL, Leiden, the Netherlands
| | - Justin L Hay
- Centre for Human Drug Research, Zernikedreef, 8,2333 CL, Leiden, the Netherlands
| | - Geert Jan Groeneveld
- Centre for Human Drug Research, Zernikedreef, 8,2333 CL, Leiden, the Netherlands
| | - Richard P Butt
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
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7
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Swain NA, Batchelor D, Beaudoin S, Bechle BM, Bradley PA, Brown AD, Brown B, Butcher KJ, Butt RP, Chapman ML, Denton S, Ellis D, Galan SRG, Gaulier SM, Greener BS, de Groot MJ, Glossop MS, Gurrell IK, Hannam J, Johnson MS, Lin Z, Markworth CJ, Marron BE, Millan DS, Nakagawa S, Pike A, Printzenhoff D, Rawson DJ, Ransley SJ, Reister SM, Sasaki K, Storer RI, Stupple PA, West CW. Discovery of Clinical Candidate 4-[2-(5-Amino-1H-pyrazol-4-yl)-4-chlorophenoxy]-5-chloro-2-fluoro-N-1,3-thiazol-4-ylbenzenesulfonamide (PF-05089771): Design and Optimization of Diaryl Ether Aryl Sulfonamides as Selective Inhibitors of NaV1.7. J Med Chem 2017; 60:7029-7042. [DOI: 10.1021/acs.jmedchem.7b00598] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
| | | | - Serge Beaudoin
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | - Bruce M. Bechle
- Worldwide
Medicinal Chemistry, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340, United States
| | | | | | | | | | | | - Mark L. Chapman
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | | | | | | | | | | | | | | | | | | | - Matthew S. Johnson
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | - Zhixin Lin
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | | | - Brian E. Marron
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | | | | | | | - David Printzenhoff
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | | | | | - Steven M. Reister
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
| | | | | | | | - Christopher W. West
- Icagen Inc., 4222 Emperor Blvd
no. 350, Durham, North Carolina 27703, United States
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8
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Okkerse P, van Amerongen G, de Kam ML, Stevens J, Butt RP, Gurrell R, Dahan A, van Gerven JM, Hay JL, Groeneveld GJ. The use of a battery of pain models to detect analgesic properties of compounds: a two-part four-way crossover study. Br J Clin Pharmacol 2017; 83:976-990. [PMID: 27862179 DOI: 10.1111/bcp.13183] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 10/30/2016] [Accepted: 11/01/2016] [Indexed: 12/29/2022] Open
Abstract
AIM The aim was to investigate the ability of a battery of pain models to detect analgesic properties of commonly used analgesics in healthy subjects. METHODS The battery consisted of tests eliciting electrical, mechanical and thermal (contact heat and cold pressor)-pain and included a UVB model, the thermal grill illusion and a paradigm of conditioned pain modulation. Subjects were administered fentanyl 3 μg kg-1 , phenytoin 300 mg, (S)-ketamine 10 mg and placebo (part I), or imipramine 100 mg, pregabalin 300 mg, ibuprofen 600 mg and placebo (part II). Pain measurements were performed at baseline and up to 10 h post-dose. Endpoints were analysed using a mixed model analysis of variance. RESULTS Sixteen subjects (8 female) completed each part. The pain tolerance threshold (PTT) for electrical stimulation was increased (all P < 0.05) compared to placebo for (S)-ketamine (+10.1%), phenytoin (+8.5%) and pregabalin (+10.8%). The PTT for mechanical pain was increased by pregabalin (+14.1%). The cold pressor PTT was increased by fentanyl (+17.1%) and pregabalin (+46.4%). Normal skin heat pain detection threshold was increased by (S)-ketamine (+3.3%), fentanyl (+2.8%) and pregabalin (+4.1%). UVB treated skin pain detection threshold was increased by fentanyl (+2.6%) and ibuprofen (+4.0%). No differences in conditioned pain modulation were observed. CONCLUSION This study shows that these pain models are able to detect changes in pain thresholds after administration of different classes of analgesics in healthy subjects. The analgesic compounds all showed a unique profile in their effects on the pain tasks administered.
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Affiliation(s)
- Pieter Okkerse
- Centre for Human Drug Research (CHDR), Leiden, The Netherlands
| | | | | | - Jasper Stevens
- Centre for Human Drug Research (CHDR), Leiden, The Netherlands
| | - Richard P Butt
- Neuroscience and Pain Research Unit, Pfizer Worldwide Research and Development, Cambridge, UK
| | - Rachel Gurrell
- Neuroscience and Pain Research Unit, Pfizer Worldwide Research and Development, Cambridge, UK
| | - Albert Dahan
- Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | | | - Justin L Hay
- Centre for Human Drug Research (CHDR), Leiden, The Netherlands
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9
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Alexandrou AJ, Brown AR, Chapman ML, Estacion M, Turner J, Mis MA, Wilbrey A, Payne EC, Gutteridge A, Cox PJ, Doyle R, Printzenhoff D, Lin Z, Marron BE, West C, Swain NA, Storer RI, Stupple PA, Castle NA, Hounshell JA, Rivara M, Randall A, Dib-Hajj SD, Krafte D, Waxman SG, Patel MK, Butt RP, Stevens EB. Subtype-Selective Small Molecule Inhibitors Reveal a Fundamental Role for Nav1.7 in Nociceptor Electrogenesis, Axonal Conduction and Presynaptic Release. PLoS One 2016; 11:e0152405. [PMID: 27050761 PMCID: PMC4822888 DOI: 10.1371/journal.pone.0152405] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 03/14/2016] [Indexed: 01/08/2023] Open
Abstract
Human genetic studies show that the voltage gated sodium channel 1.7 (Nav1.7) is a key molecular determinant of pain sensation. However, defining the Nav1.7 contribution to nociceptive signalling has been hampered by a lack of selective inhibitors. Here we report two potent and selective arylsulfonamide Nav1.7 inhibitors; PF-05198007 and PF-05089771, which we have used to directly interrogate Nav1.7’s role in nociceptor physiology. We report that Nav1.7 is the predominant functional TTX-sensitive Nav in mouse and human nociceptors and contributes to the initiation and the upstroke phase of the nociceptor action potential. Moreover, we confirm a role for Nav1.7 in influencing synaptic transmission in the dorsal horn of the spinal cord as well as peripheral neuropeptide release in the skin. These findings demonstrate multiple contributions of Nav1.7 to nociceptor signalling and shed new light on the relative functional contribution of this channel to peripheral and central noxious signal transmission.
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Affiliation(s)
- Aristos J. Alexandrou
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Adam R. Brown
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Mark L. Chapman
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - Mark Estacion
- Center for Neuroscience & Regeneration Research, Yale Medical School and Veterans Affairs Hospital, West Haven, CT, 06516, United States of America
| | - Jamie Turner
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Malgorzata A. Mis
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Anna Wilbrey
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Elizabeth C. Payne
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Alex Gutteridge
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Peter J. Cox
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Rachel Doyle
- Pfizer Global R&D, Ramsgate Road, Sandwich, Kent, CT13 9NJ, United Kingdom
| | - David Printzenhoff
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - Zhixin Lin
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - Brian E. Marron
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - Christopher West
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - Nigel A. Swain
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - R. Ian Storer
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Paul A. Stupple
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
| | - Neil A. Castle
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - James A. Hounshell
- Dept. Anesthesiology, University of Virginia Health System, Charlottesville, Virginia, 22911, United States of America
| | - Mirko Rivara
- Dept. Anesthesiology, University of Virginia Health System, Charlottesville, Virginia, 22911, United States of America
| | - Andrew Randall
- Medical School, Hatherly Building, University of Exeter, Prince of Wales Road, Exeter, EX4 4PS, United Kingdom
| | - Sulayman D. Dib-Hajj
- Center for Neuroscience & Regeneration Research, Yale Medical School and Veterans Affairs Hospital, West Haven, CT, 06516, United States of America
| | - Douglas Krafte
- Pfizer Neusentis, 4222 Emperor Boulevard, Durham, North Carolina, 27703, United States of America
| | - Stephen G. Waxman
- Center for Neuroscience & Regeneration Research, Yale Medical School and Veterans Affairs Hospital, West Haven, CT, 06516, United States of America
| | - Manoj K. Patel
- Dept. Anesthesiology, University of Virginia Health System, Charlottesville, Virginia, 22911, United States of America
| | - Richard P. Butt
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
- * E-mail: (EBS); (RPB)
| | - Edward B. Stevens
- Pfizer Neusentis, The Portway Buiding, Granta Park, Great Abington, Cambridge, CB21 6GS, United Kingdom
- * E-mail: (EBS); (RPB)
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10
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Payne CE, Brown AR, Theile JW, Loucif AJC, Alexandrou AJ, Fuller MD, Mahoney JH, Antonio BM, Gerlach AC, Printzenhoff DM, Prime RL, Stockbridge G, Kirkup AJ, Bannon AW, England S, Chapman ML, Bagal S, Roeloffs R, Anand U, Anand P, Bungay PJ, Kemp M, Butt RP, Stevens EB. A novel selective and orally bioavailable Nav 1.8 channel blocker, PF-01247324, attenuates nociception and sensory neuron excitability. Br J Pharmacol 2015; 172:2654-70. [PMID: 25625641 DOI: 10.1111/bph.13092] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE NaV 1.8 ion channels have been highlighted as important molecular targets for the design of low MW blockers for the treatment of chronic pain. Here, we describe the effects of PF-01247324, a new generation, selective, orally bioavailable Nav 1.8 channel blocker of novel chemotype. EXPERIMENTAL APPROACH The inhibition of Nav 1.8 channels by PF-01247324 was studied using in vitro patch-clamp electrophysiology and the oral bioavailability and antinociceptive effects demonstrated using in vivo rodent models of inflammatory and neuropathic pain. KEY RESULTS PF-01247324 inhibited native tetrodotoxin-resistant (TTX-R) currents in human dorsal root ganglion (DRG) neurons (IC50 : 331 nM) and in recombinantly expressed h Nav 1.8 channels (IC50 : 196 nM), with 50-fold selectivity over recombinantly expressed TTX-R hNav 1.5 channels (IC50 : ∼10 μM) and 65-100-fold selectivity over TTX-sensitive (TTX-S) channels (IC50 : ∼10-18 μM). Native TTX-R currents in small-diameter rodent DRG neurons were inhibited with an IC50 448 nM, and the block of both human recombinant Nav 1.8 channels and TTX-R from rat DRG neurons was both frequency and state dependent. In vitro current clamp showed that PF-01247324 reduced excitability in both rat and human DRG neurons and also altered the waveform of the action potential. In vivo experiments n rodents demonstrated efficacy in both inflammatory and neuropathic pain models. CONCLUSIONS AND IMPLICATIONS Using PF-01247324, we have confirmed a role for Nav 1.8 channels in both inflammatory and neuropathic pain. We have also demonstrated a key role for Nav 1.8 channels in action potential upstroke and repetitive firing of rat and human DRG neurons.
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Shields SD, Butt RP, Dib-Hajj SD, Waxman SG. Oral administration of PF-01247324, a subtype-selective Nav1.8 blocker, reverses cerebellar deficits in a mouse model of multiple sclerosis. PLoS One 2015; 10:e0119067. [PMID: 25747279 PMCID: PMC4352054 DOI: 10.1371/journal.pone.0119067] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 01/26/2015] [Indexed: 01/16/2023] Open
Abstract
Cerebellar symptoms significantly diminish quality of life in patients with multiple sclerosis (MS). We previously showed that sodium channel Nav1.8, although normally restricted to peripheral somatosensory neurons, is upregulated in the cerebellum in MS, and that Nav1.8 expression is linked to ataxia and MS-like symptoms in mice. Furthermore, intracerebroventricular administration of the Nav1.8 blocker A-803467 temporarily reversed electrophysiological and behavioral manifestations of disease in a mouse MS model; unfortunately A-803467 is not orally bioavailable, diminishing the potential for translation to human patients. In the present study, we assessed the effect of per os (p.o.) dosing of a new orally bioavailable Nav1.8-selective blocker, PF-01247324, in transgenic mice expressing Nav1.8 in Purkinje neurons, and in wildtype mice in the experimental autoimmune encephalomyelitis (EAE) model. PF-01247324 was administered by oral gavage at 1000 mg/kg; control groups received an equal volume of vehicle. Behavioral assays of motor coordination, grip strength, and ataxia were performed. We observed significant improvements in motor coordination and cerebellar-like symptoms in mice that received PF-01247324 compared to control littermates that received vehicle. These preclinical proof-of-concept data suggest that PF-01247324, its derivatives, or other Nav1.8-selective blockers merit further study for providing symptomatic therapy for cerebellar dysfunction in MS and related disorders.
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Affiliation(s)
- Shannon D. Shields
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Rehabilitation Research Center, Veterans’ Affairs Connecticut Healthcare System, West Haven, Connecticut, United States of America
| | | | - Sulayman D. Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Rehabilitation Research Center, Veterans’ Affairs Connecticut Healthcare System, West Haven, Connecticut, United States of America
| | - Stephen G. Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Rehabilitation Research Center, Veterans’ Affairs Connecticut Healthcare System, West Haven, Connecticut, United States of America
- * E-mail:
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Hull ML, Prentice A, Wang DY, Butt RP, Phillips SC, Smith SK, Charnock-Jones DS. Nimesulide, a COX-2 inhibitor, does not reduce lesion size or number in a nude mouse model of endometriosis. Hum Reprod 2004; 20:350-8. [PMID: 15567877 DOI: 10.1093/humrep/deh611] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Women with endometriosis have elevated levels of cyclooxygenase-2 (COX-2) in peritoneal macrophages and endometriotic tissue. Inhibition of COX-2 has been shown to reduce inflammation, angiogenesis and cellular proliferation. It may also downregulate aromatase activity in ectopic endometrial lesions. Ectopic endometrial establishment and growth are therefore likely to be suppressed in the presence of COX-2 inhibitors. We hypothesized that COX-2 inhibition would reduce the size and number of ectopic human endometrial lesions in a nude mouse model of endometriosis. METHODS The selective COX-2 inhibitor, nimesulide, was administered to estrogen-supplemented nude mice implanted with human endometrial tissue. Ten days after implantation, the number and size of ectopic endometrial lesions were evaluated and compared with lesions from a control group. Immunohistochemical assessment of vascular development and macrophage and myofibroblast infiltration in control and treated lesions was performed. RESULTS There was no difference in the number or size of ectopic endometrial lesions in control and nimesulide-treated nude mice. Nimesulide did not induce a visually identifiable difference in blood vessel development or macrophage or myofibroblast infiltration in nude mouse explants. CONCLUSION The hypothesized biological properties of COX-2 inhibition did not influence lesion number or size in the nude mouse model of endometriosis.
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Affiliation(s)
- M L Hull
- Reproductive Molecular Research Group, Department of Pathology Tennis Court Road, Cambridge CB2 1QP, UK.
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Abstract
The mechanical environment is a key determinant of cellular activity in many tissues. In the cardiovascular system it plays a role in tissue remodelling during both development and disease. In the heart changes in mechanical tension stimulate myocyte hypertrophy and fibroblast collagen synthesis. To elucidate the mechanisms for the latter response, we determined the direct effect of mechanical load on cardiac fibroblast activity. Primary cultures of fetal rat cardiac fibroblasts were mechanically loaded in the presence or absence of fetal calf serum or growth factors, and the effects on fibroblast replication and procollagen metabolism and gene expression determined. Procollagen synthesis was increased by 99.7 +/- 4.3% in response to mechanical load and 10% fetal calf serum, compared to 10% fetal calf serum control (P<0.01) after 48 h. Procollagen alpha1(I) steady-state mRNA levels were increased two-fold. No effect was observed in the absence of serum. Transforming growth factor beta1 and insulin-like growth factor 1 have been demonstrated to stimulate procollagen metabolism by these cells. Mechanical load enhanced the response to these growth factors, stimulating alpha1(I) mRNA levels by 4.3 and three-fold, respectively, above growth factor alone controls. These results demonstrate a synergistic effect on procollagen gene expression and metabolism by mechanical load and profibrotic growth factors. Since these factors are released during the development of cardiac hypertrophy, interactions between the mechanical environment and these polypeptides may provide a mechanism for enhanced collagen deposition in the heart.
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Affiliation(s)
- R P Butt
- Centre for Cardiopulmonary Biochemistry & Respiratory Medicine, University College London Medical School, UK
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Butt RP, Laurent GJ, Bishop JE. Collagen production and replication by cardiac fibroblasts is enhanced in response to diverse classes of growth factors. Eur J Cell Biol 1995; 68:330-5. [PMID: 8603686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The tissue distribution and cellular effects of platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), transforming growth factor beta-1 (TGF beta 1) and insulin-like growth factor 1 (IGF-1) suggest a potential role for these factors in cardiovascular matrix deposition. The objective of this study was to assess the capacity of these growth factors to promote cardiac fibroblast collagen production and replication in vitro which will lead to studies identifying their role in vivo during cardiac development and disease. Fibroblasts were isolated from fetal rat hearts by explant culture, and their response to growth factors was assessed with respect to fibroblast replication and collagen synthesis. Fibroblast replication was stimulated by PDGF and by bFGF.IGF-1 and TGF beta 1 had no effect on fibroblast replication. Collagen production was stimulated by all of the growth factors tested in order of potency TGF beta 1 > PDGF, IGF > bFGF. None of the growth factors affected the proportion of newly synthesized collagen rapidly degraded. We have shown that TGF beta 1, PDGF, bFGF and IGF-1 are all capable of increasing collagen deposition by cardiac fibroblasts by either stimulating fibroblast replication or collagen synthesis or both. The sensitivity of cardiac fibroblasts to these factors is consistent with their playing a role in the rapid changes in cardiac collagen deposition seen during development and disease.
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Affiliation(s)
- R P Butt
- Division of Cardiopulmonary Biochemistry, University College London Medical School, Rayne Institute, United Kingdom
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Affiliation(s)
- R P Butt
- Division of Cardiopulmonary Biochemistry, University College London Medical School, Rayne Institute, London, United Kingdom
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