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Sachau J, Sendel M, Péchard M, Schnabel K, Schmieg I, Medkour T, Ecochard L, Woischnik M, Liedgens H, Pogatzki-Zahn E, Baron R, Bouhassira D. Patient Reported Outcome Measures in Chronic Neuropathic Pain Clinical Trials - A Systematic Literature Review. THE JOURNAL OF PAIN 2023; 24:38-54. [PMID: 36216128 DOI: 10.1016/j.jpain.2022.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 08/22/2022] [Accepted: 09/01/2022] [Indexed: 11/05/2022]
Abstract
In neuropathic pain clinical trials, the patient's perspective is often insufficiently reflected focusing mainly on pain intensity. Comparability of outcome assessment is limited due to heterogenous patient reported outcome measures (PROMs). The MEDLINE, CENTRAL, and Embase databases and reference lists of published meta-analyses were searched. Randomized controlled studies assessing treatment efficacy of drugs for chronic neuropathic pain were included. PROMs were assigned to recommended IMMPACT/NeuPSIG domains: pain intensity, pain other aspects, physical functioning, emotional functioning, global improvement and satisfaction, adverse events, participant disposition. Domains and PROMs were compared regarding the publication year and methodological quality of the studies. Within the 251 included studies 200 PROMs were used with 27 being recommended by IMMPACT/NeuPSIG. The number of domains was higher in high/moderate quality studies. The (sub-) domains 'physical functioning', 'global improvement and satisfaction', and 'neuropathic pain quality' were assessed more frequently in high/moderate quality studies and those published after 2011. Recent studies and those of better quality more often used the recommended PROMs. Although neuropathic assessment via PROMs has improved, there is still a high heterogeneity. A standardized core set of outcome domains and should be defined to improve neuropathic pain treatment and to achieve better comparability of clinical trials. Perspective: This systematic literature review assesses the use of patient reported outcome measures (PROMs) in chronic neuropathic pain. The results show that there is still a high heterogeneity, highlighting the need for a standardized core set of outcome domains and PROMs to improve comparability of clinical trials and neuropathic pain treatment.
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Affiliation(s)
- Juliane Sachau
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany.
| | - Manon Sendel
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Marie Péchard
- Inserm U987, APHP, UVSQ, Paris-Saclay University, CHU Ambroise Paré, Boulogne-Billancourt, France
| | - Kathrin Schnabel
- Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital of Muenster, Münster
| | - Iris Schmieg
- Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital of Muenster, Münster
| | - Terkia Medkour
- Inserm U987, APHP, UVSQ, Paris-Saclay University, CHU Ambroise Paré, Boulogne-Billancourt, France
| | | | | | | | - Esther Pogatzki-Zahn
- Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital of Muenster, Münster
| | - Ralf Baron
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Didier Bouhassira
- Inserm U987, APHP, UVSQ, Paris-Saclay University, CHU Ambroise Paré, Boulogne-Billancourt, France
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Sloan G, Alam U, Selvarajah D, Tesfaye S. The Treatment of Painful Diabetic Neuropathy. Curr Diabetes Rev 2022; 18:e070721194556. [PMID: 34238163 DOI: 10.2174/1573399817666210707112413] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/18/2021] [Accepted: 03/08/2021] [Indexed: 11/22/2022]
Abstract
Painful diabetic peripheral neuropathy (painful-DPN) is a highly prevalent and disabling condition, affecting up to one-third of patients with diabetes. This condition can have a profound impact resulting in a poor quality of life, disruption of employment, impaired sleep, and poor mental health with an excess of depression and anxiety. The management of painful-DPN poses a great challenge. Unfortunately, currently there are no Food and Drug Administration (USA) approved disease-modifying treatments for diabetic peripheral neuropathy (DPN) as trials of putative pathogenetic treatments have failed at phase 3 clinical trial stage. Therefore, the focus of managing painful- DPN other than improving glycaemic control and cardiovascular risk factor modification is treating symptoms. The recommended treatments based on expert international consensus for painful- DPN have remained essentially unchanged for the last decade. Both the serotonin re-uptake inhibitor (SNRI) duloxetine and α2δ ligand pregabalin have the most robust evidence for treating painful-DPN. The weak opioids (e.g. tapentadol and tramadol, both of which have an SNRI effect), tricyclic antidepressants such as amitriptyline and α2δ ligand gabapentin are also widely recommended and prescribed agents. Opioids (except tramadol and tapentadol), should be prescribed with caution in view of the lack of definitive data surrounding efficacy, concerns surrounding addiction and adverse events. Recently, emerging therapies have gained local licenses, including the α2δ ligand mirogabalin (Japan) and the high dose 8% capsaicin patch (FDA and Europe). The management of refractory painful-DPN is difficult; specialist pain services may offer off-label therapies (e.g. botulinum toxin, intravenous lidocaine and spinal cord stimulation), although there is limited clinical trial evidence supporting their use. Additionally, despite combination therapy being commonly used clinically, there is little evidence supporting this practise. There is a need for further clinical trials to assess novel therapeutic agents, optimal combination therapy and existing agents to determine which are the most effective for the treatment of painful-DPN. This article reviews the evidence for the treatment of painful-DPN, including emerging treatment strategies such as novel compounds and stratification of patients according to individual characteristics (e.g. pain phenotype, neuroimaging and genotype) to improve treatment responses.
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Affiliation(s)
- Gordon Sloan
- Diabetes Research Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
| | - Uazman Alam
- Department of Cardiovascular and Metabolic Medicine and the Pain Research Institute, Institute of Life Course and Medical Sciences, University of Liverpool, and Liverpool University Hospital, NHS Foundation Trust, Liverpool, UK
- Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester, Manchester, UK
| | - Dinesh Selvarajah
- Diabetes Research Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
- Department of Oncology and Human Metabolism, University of Sheffield, Sheffield, UK
| | - Solomon Tesfaye
- Diabetes Research Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
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Pafili K, Papanas N. Considerations for single- versus multiple-drug pharmacotherapy in the management of painful diabetic neuropathy. Expert Opin Pharmacother 2021; 22:2267-2280. [PMID: 33819123 DOI: 10.1080/14656566.2021.1909570] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION The efficacy of monotherapy to reduce pain from diabetic peripheral neuropathy (DPN) is frequently not satisfactory and guidelines do not provide unanimous treatment options. In this context, multiple drug pharmacotherapy may provide benefit. AREAS COVERED The aim of the present review is to describe the clinical trials addressing the pharmacotherapy of painful DPN. Studies discussing efficacy and tolerability of pharmacological agents that were assessed in monotherapy and in combination treatment are reported and discussed. EXPERT OPINION Several clinical trials have reported benefit of multiple-drug pharmacotherapy. Nevertheless, untoward effects of combination treatment are of concern. Importantly, some trials were restricted to comparison with placebo and other compared only with active comparator(s). Only limited clinical trials assessed selected cohorts of individuals experiencing different stages of painful DPN. Despite current limitations, some evidence of studies implicating a comparison to all active comparators points to safety and effectiveness of the combination of oxycodone with pregabalin and that of pregabalin with the 5% lidocaine plaster but future, clear-cut studies are required to drive evidence-based decisions in the clinical setting.
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Affiliation(s)
- Kalliopi Pafili
- Diabetes Centre, Second Department of Internal Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Nikolaos Papanas
- Diabetes Centre, Second Department of Internal Medicine, Democritus University of Thrace, Alexandroupolis, Greece
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Löscher W, Sills GJ, White HS. The ups and downs of alkyl-carbamates in epilepsy therapy: How does cenobamate differ? Epilepsia 2021; 62:596-614. [PMID: 33580520 DOI: 10.1111/epi.16832] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 12/13/2022]
Abstract
Since 1955, several alkyl-carbamates have been developed for the treatment of anxiety and epilepsy, including meprobamate, flupirtine, felbamate, retigabine, carisbamate, and cenobamate. They have each enjoyed varying levels of success as antiseizure drugs; however, they have all been plagued by the emergence of serious and sometimes life-threatening adverse events. In this review, we compare and contrast their predominant molecular mechanisms of action, their antiseizure profile, and where possible, their clinical efficacy. The preclinical, clinical, and mechanistic profile of the prototypical γ-aminobutyric acidergic (GABAergic) modulator phenobarbital is included for comparison. Like phenobarbital, all of the clinically approved alkyl-carbamates share an ability to enhance inhibitory neurotransmission through modulation of the GABAA receptor, although the specific mechanism of interaction differs among the different drugs discussed. In addition, several alkyl-carbamates have been shown to interact with voltage-gated ion channels. Flupirtine and retigabine share an ability to activate K+ currents mediated by KCNQ (Kv7) K+ channels, and felbamate, carisbamate, and cenobamate have been shown to block Na+ channels. In contrast to other alkyl-carbamates, cenobamate seems to be unique in its ability to preferentially attenuate the persistent rather than transient Na+ current. Results from recent randomized controlled clinical trials with cenobamate suggest that this newest antiseizure alkyl-carbamate possesses a degree of efficacy not witnessed since felbamate was approved in 1993. Given that ceno-bamate's mechanistic profile is unique among the alkyl-carbamates, it is not clear whether this impressive efficacy reflects an as yet undescribed mechanism of action or whether it possesses a unique synergy between its actions at the GABAA receptor and on persistent Na+ currents. The high efficacy of cenobamate is, however, tempered by the risk of serious rash and low tolerability at higher doses, meaning that further safety studies and clinical experience are needed to determine the true clinical value of cenobamate.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, Hannover, Germany
| | - Graeme J Sills
- School of Life Sciences, University of Glasgow, Glasgow, UK
| | - H Steve White
- Department of Pharmacy, School of Pharmacy, University of Washington, Seattle, Washington, USA
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Alam U, Sloan G, Tesfaye S. Treating Pain in Diabetic Neuropathy: Current and Developmental Drugs. Drugs 2020; 80:363-384. [DOI: 10.1007/s40265-020-01259-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Abstract
BACKGROUND This review updates part of an earlier Cochrane Review titled "Pregabalin for acute and chronic pain in adults", and considers only neuropathic pain (pain from damage to nervous tissue). Antiepileptic drugs have long been used in pain management. Pregabalin is an antiepileptic drug used in management of chronic pain conditions. OBJECTIVES To assess the analgesic efficacy and adverse effects of pregabalin for chronic neuropathic pain in adults. SEARCH METHODS We searched CENTRAL, MEDLINE, and Embase for randomised controlled trials from January 2009 to April 2018, online clinical trials registries, and reference lists. SELECTION CRITERIA We included randomised, double-blind trials of two weeks' duration or longer, comparing pregabalin (any route of administration) with placebo or another active treatment for neuropathic pain, with participant-reported pain assessment. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data and assessed trial quality and biases. Primary outcomes were: at least 30% pain intensity reduction over baseline; much or very much improved on the Patient Global Impression of Change (PGIC) Scale (moderate benefit); at least 50% pain intensity reduction; or very much improved on PGIC (substantial benefit). We calculated risk ratio (RR) and number needed to treat for an additional beneficial (NNTB) or harmful outcome (NNTH). We assessed the quality of the evidence using GRADE. MAIN RESULTS We included 45 studies lasting 2 to 16 weeks, with 11,906 participants - 68% from 31 new studies. Oral pregabalin doses of 150 mg, 300 mg, and 600 mg daily were compared with placebo. Postherpetic neuralgia, painful diabetic neuropathy, and mixed neuropathic pain predominated (85% of participants). High risk of bias was due mainly to small study size (nine studies), but many studies had unclear risk of bias, mainly due to incomplete outcome data, size, and allocation concealment.Postherpetic neuralgia: More participants had at least 30% pain intensity reduction with pregabalin 300 mg than with placebo (50% vs 25%; RR 2.1 (95% confidence interval (CI) 1.6 to 2.6); NNTB 3.9 (3.0 to 5.6); 3 studies, 589 participants, moderate-quality evidence), and more had at least 50% pain intensity reduction (32% vs 13%; RR 2.5 (95% CI 1.9 to 3.4); NNTB 5.3 (3.9 to 8.1); 4 studies, 713 participants, moderate-quality evidence). More participants had at least 30% pain intensity reduction with pregabalin 600 mg than with placebo (62% vs 24%; RR 2.5 (95% CI 2.0 to 3.2); NNTB 2.7 (2.2 to 3.7); 3 studies, 537 participants, moderate-quality evidence), and more had at least 50% pain intensity reduction (41% vs 15%; RR 2.7 (95% CI 2.0 to 3.5); NNTB 3.9 (3.1 to 5.5); 4 studies, 732 participants, moderate-quality evidence). Somnolence and dizziness were more common with pregabalin than with placebo (moderate-quality evidence): somnolence 300 mg 16% versus 5.5%, 600 mg 25% versus 5.8%; dizziness 300 mg 29% versus 8.1%, 600 mg 35% versus 8.8%.Painful diabetic neuropathy: More participants had at least 30% pain intensity reduction with pregabalin 300 mg than with placebo (47% vs 42%; RR 1.1 (95% CI 1.01 to 1.2); NNTB 22 (12 to 200); 8 studies, 2320 participants, moderate-quality evidence), more had at least 50% pain intensity reduction (31% vs 24%; RR 1.3 (95% CI 1.2 to 1.5); NNTB 22 (12 to 200); 11 studies, 2931 participants, moderate-quality evidence), and more had PGIC much or very much improved (51% vs 30%; RR 1.8 (95% CI 1.5 to 2.0); NNTB 4.9 (3.8 to 6.9); 5 studies, 1050 participants, moderate-quality evidence). More participants had at least 30% pain intensity reduction with pregabalin 600 mg than with placebo (63% vs 52%; RR 1.2 (95% CI 1.04 to 1.4); NNTB 9.6 (5.5 to 41); 2 studies, 611 participants, low-quality evidence), and more had at least 50% pain intensity reduction (41% vs 28%; RR 1.4 (95% CI 1.2 to 1.7); NNTB 7.8 (5.4 to 14); 5 studies, 1015 participants, low-quality evidence). Somnolence and dizziness were more common with pregabalin than with placebo (moderate-quality evidence): somnolence 300 mg 11% versus 3.1%, 600 mg 15% versus 4.5%; dizziness 300 mg 13% versus 3.8%, 600 mg 22% versus 4.4%.Mixed or unclassified post-traumatic neuropathic pain: More participants had at least 30% pain intensity reduction with pregabalin 600 mg than with placebo (48% vs 36%; RR 1.2 (1.1 to 1.4); NNTB 8.2 (5.7 to 15); 4 studies, 1367 participants, low-quality evidence), and more had at least 50% pain intensity reduction (34% vs 20%; RR 1.5 (1.2 to 1.9); NNTB 7.2 (5.4 to 11); 4 studies, 1367 participants, moderate-quality evidence). Somnolence (12% vs 3.9%) and dizziness (23% vs 6.2%) were more common with pregabalin.Central neuropathic pain: More participants had at least 30% pain intensity reduction with pregabalin 600 mg than with placebo (44% vs 28%; RR 1.6 (1.3 to 2.0); NNTB 5.9 (4.1 to 11); 3 studies, 562 participants, low-quality evidence) and at least 50% pain intensity reduction (26% vs 15%; RR 1.7 (1.2 to 2.3); NNTB 9.8 (6.0 to 28); 3 studies, 562 participants, low-quality evidence). Somnolence (32% vs 11%) and dizziness (23% vs 8.6%) were more common with pregabalin.Other neuropathic pain conditions: Studies show no evidence of benefit for 600 mg pregabalin in HIV neuropathy (2 studies, 674 participants, moderate-quality evidence) and limited evidence of benefit in neuropathic back pain or sciatica, neuropathic cancer pain, or polyneuropathy.Serious adverse events, all conditions: Serious adverse events were no more common with placebo than with pregabalin 300 mg (3.1% vs 2.6%; RR 1.2 (95% CI 0.8 to 1.7); 17 studies, 4112 participants, high-quality evidence) or pregabalin 600 mg (3.4% vs 3.4%; RR 1.1 (95% CI 0.8 to 1.5); 16 studies, 3995 participants, high-quality evidence). AUTHORS' CONCLUSIONS Evidence shows efficacy of pregabalin in postherpetic neuralgia, painful diabetic neuralgia, and mixed or unclassified post-traumatic neuropathic pain, and absence of efficacy in HIV neuropathy; evidence of efficacy in central neuropathic pain is inadequate. Some people will derive substantial benefit with pregabalin; more will have moderate benefit, but many will have no benefit or will discontinue treatment. There were no substantial changes since the 2009 review.
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Affiliation(s)
| | - Rae Frances Bell
- Haukeland University HospitalRegional Centre of Excellence in Palliative CareBergenNorway
| | - Sebastian Straube
- University of AlbertaDepartment of Medicine, Division of Preventive Medicine5‐30 University Terrace8303‐112 StreetEdmontonCanadaT6G 2T4
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van Nooten F, Treur M, Pantiri K, Stoker M, Charokopou M. Capsaicin 8% Patch Versus Oral Neuropathic Pain Medications for the Treatment of Painful Diabetic Peripheral Neuropathy: A Systematic Literature Review and Network Meta-analysis. Clin Ther 2017; 39:787-803.e18. [PMID: 28365034 DOI: 10.1016/j.clinthera.2017.02.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 02/20/2017] [Accepted: 02/22/2017] [Indexed: 12/21/2022]
Abstract
PURPOSE A network meta-analysis (NMA) was performed, aiming to assess the relative efficacy and tolerability of the capsaicin 179-mg (8% weight for weight) cutaneous patch (capsaicin 8% patch) compared with oral, centrally acting agents (ie, pregabalin, gabapentin, duloxetine, amitriptyline) in patients with painful diabetic peripheral neuropathy (PDPN). METHODS A systematic search of EMBASE/MEDLINE, Cochrane Library, and the National Health Service Centre for Reviews and Dissemination Database of Abstracts of Reviews of Effects was conducted to identify all randomized controlled trials. Data from eligible studies according to predefined inclusion and exclusion criteria were extracted, and analyses were based on aggregate-level data. Efficacy outcomes were the proportions of patients with ≥30% and ≥50% reductions in pain, and tolerability outcomes were somnolence, dizziness, nausea, diarrhea, constipation, headache, fatigue, insomnia, and rate of discontinuation due to adverse events (AEs). Data were analyzed by using a Bayesian NMA. Fixed and random effects models were estimated. Relative treatment effect was presented as odds ratios (ORs) with 95% CIs. Sources of heterogeneity were assessed. FINDINGS The NMA included 25 randomized controlled trials. For ≥30% pain reduction, the capsaicin 8% patch was significantly more effective than placebo (OR, 2.28 [95% CI, 1.19-4.03]), exhibited a numerical advantage compared with pregabalin (OR, 1.83 [95% CI, 0.91-3.34]) and gabapentin (OR, 1.66 [95% CI, 0.74-3.23]), and had similar efficacy compared with duloxetine (OR, 0.99 [95% CI, 0.5-1.79]). The evidence available was not sufficient to assess the relative efficacy of amitriptyline. In the NMA for tolerability, the capsaicin 8% patch was only included for headache because the incidence was 0% for the other outcomes. Oral, centrally acting agents had a significantly elevated risk compared with placebo for somnolence (pregabalin, gabapentin, duloxetine, and amitriptyline), dizziness (pregabalin, gabapentin, duloxetine, and amitriptyline), nausea (duloxetine), diarrhea (duloxetine), fatigue (duloxetine), and discontinuation because of AEs (pregabalin, gabapentin, and duloxetine). Compared with pregabalin and gabapentin, duloxetine had a significantly lower risk of dizziness but a significantly higher risk of nausea. IMPLICATIONS This NMA suggests that the efficacy observed with the capsaicin 8% patch is similar to that observed with oral agents (ie, pregabalin, duloxetine, gabapentin) in patients with PDPN. The oral agents were associated with a significantly elevated risk of somnolence, dizziness, fatigue, and discontinuation because of AEs compared with placebo. The capsaicin 8% patch was as effective as oral centrally acting agents in these patients with PDPN but offers systemic tolerability benefits.
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Affiliation(s)
| | | | | | - Malcolm Stoker
- Astellas Pharma Europe BV, Medical Affairs, Leiden, The Netherlands
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SCN9A Variants May be Implicated in Neuropathic Pain Associated With Diabetic Peripheral Neuropathy and Pain Severity. Clin J Pain 2016; 31:976-82. [PMID: 25585270 PMCID: PMC4894774 DOI: 10.1097/ajp.0000000000000205] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Supplemental Digital Content is available in the text. Objectives: Previous studies have established the role of SCN9A in various pain conditions, including idiopathic small fiber neuropathy. In the present study, we interrogate the relationship between common and rare variants in SCN9A gene and chronic neuropathic pain associated with diabetic peripheral neuropathy. Design: Using a cohort of 938 patients of European ancestry with chronic neuropathic pain associated with diabetic peripheral neuropathy enrolled in 6 clinical studies and 2 controls (POPRES, n=2624 and Coriell, n=1029), we examined the relationship between SCN9A variants and neuropathic pain in a case-control study using a 2-stage design. The exonic regions of SCN9A were sequenced in a subset of 244 patients with neuropathic pain, and the variants discovered were compared with POPRES control (stage 1). The top associated variants were followed up by genotyping in the entire case collection and Coriell controls restricting the analysis to the matching patients from the United States and Canada only (stage 2). Results: Seven variants were found to be associated with neuropathic pain at the sequencing stage. Four variants (Asp1908Gly, Val991Leu/Met932Leu, and an intronic variant rs74449889) were confirmed by genotyping to occur at a higher frequency in cases than controls (odds ratios ∼2.1 to 2.6, P=0.05 to 0.009). Val991Leu/Met932Leu was also associated with the severity of pain as measured by pain score Numeric Rating Scale (NRS-11, P=0.047). Val991Leu/Met932Leu variants were in complete linkage disequilibrium and previously shown to cause hyperexcitability in dorsal root ganglia neurons. Conclusions: The association of SCN9A variants with neuropathic pain and pain severity suggests a role of SCN9A in the disease etiology of neuropathic pain.
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ZHANG SS, WU Z, ZHANG LC, ZHANG Z, CHEN RP, HUANG YH, CHEN H. Efficacy and safety of pregabalin for treating painful diabetic peripheral neuropathy: a meta-analysis. Acta Anaesthesiol Scand 2015; 59:147-59. [PMID: 25328117 DOI: 10.1111/aas.12420] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 09/07/2014] [Indexed: 12/21/2022]
Abstract
BACKGROUND Pregabalin is considered to be an effective treatment for painful diabetic peripheral neuropathy (DPN), but controversy exists about its efficacy and safety. We performed a meta-analysis to systematically assess the efficacy and safety of pregabalin for managing pain associated with DPN. METHODS Medline, EMBASE, and the Cochrane Central Register were searched in July 2014 for randomized, double-blind, placebo-controlled trials published in English on the use of pregabalin to treat DPN-associated pain. Principal outcomes were mean pain score after pregabalin treatment and the proportions of patients showing a pain reduction of at least 50%. RESULTS Nine trials involving a total of 2056 participants were identified. Pooled analysis showed that pregabalin was significantly superior to placebo for improving mean pain scores [mean difference (MD) = -0.79, P < 0.001]. Pregabalin reduced pain below baseline by at least 50% in a significantly greater proportion of patients than placebo did [relative risk = 1.54, P < 0.001]. Patients were more likely to self-report their status as 'improved' after taking pregabalin than placebo (relative risk = 1.38, P < 0.001). Pregabalin also improved sleep quality more than placebo (MD = -0.88, P < 0.001). On the other hand, patients receiving pregabalin were more likely to experience mild side effects than were patients receiving placebo. CONCLUSIONS Our meta-analysis indicates that pregabalin is more effective than placebo for managing DPN-associated pain and other symptoms that reduce quality of life. The drug is also reasonably well tolerated.
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Affiliation(s)
- S.-S. ZHANG
- Department of Endocrinology; Zhujiang Hospital; Southern Medical University; Guangzhou China
| | - Z. WU
- Department of Neurology; Nanfang Hospital; Southern Medical University; Guangzhou China
| | - L.-C. ZHANG
- Department of Anorectal Surgery; The Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine; Nanchang China
| | - Z. ZHANG
- Department of Endocrinology; Zhujiang Hospital; Southern Medical University; Guangzhou China
| | - R.-P. CHEN
- Department of Endocrinology; Zhujiang Hospital; Southern Medical University; Guangzhou China
| | - Y.-H. HUANG
- Department of Colorectal and Anal Surgery; First Affiliated Hospital; Guangxi Medical University; Nanning Guangxi China
| | - H. CHEN
- Department of Endocrinology; Zhujiang Hospital; Southern Medical University; Guangzhou China
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Arakawa A, Kaneko M, Narukawa M. An Investigation of Factors Contributing to Higher Levels of Placebo Response in Clinical Trials in Neuropathic Pain: A Systematic Review and Meta-Analysis. Clin Drug Investig 2015; 35:67-81. [DOI: 10.1007/s40261-014-0259-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Adeghate E, Fehér E, Kalász H. Evaluating the Phase II drugs currently under investigation for diabetic neuropathy. Expert Opin Investig Drugs 2014; 24:1-15. [PMID: 25171371 DOI: 10.1517/13543784.2014.954033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Introduction: The worldwide number of patients suffering from diabetes mellitus (DM) is projected to approach 552 million by the year 2030. As diabetic neuropathy (DN) is present in 8% of new diabetic patients at the time of diagnosis and occurs in ∼ 50% of all patients with established DM, the number of patients who will develop painful DN will also increase. The suboptimal efficacies of currently approved drugs have prompted investigators to develop new therapeutic agents for the management of painful DN. Areas covered: In this review, the authors present and elucidate the current status of drugs under investigation for the treatment of painful DN. A short synopsis of currently approved drugs is also given. Literature information and data analysis were retrieved from PubMed, the American Diabetes and Neurological Associations Websites and ClinicalTrials.gov. The keywords used in the search included: DM, DN, painful diabetic neuropathy. Expert opinion: In addition to treating the pain associated with DN, the actual causes of the disease should also be targeted for improved management. It is hoped that drugs which improve vascular blood flow, induce neural regeneration, reduce hyperglycemia, oxidative stress and inflammation can be more effective for the overall treatment of painful DN.
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Affiliation(s)
- Ernest Adeghate
- United Arab Emirates University, College of Medicine and Health Sciences, Department of Anatomy , P.O Box 17666, Al Ain , UAE +971 3 7672033 ;
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