Evaluation of the Efficacy, Tolerability and Safety of Etoricoxib (Arcoxia) in Patients With Neuropathic Pain

Study Overview
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Brief Summary
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The present study will aim to determine the safety, efficacy, and tolerability of etoricoxib, an NSAID pain reliever, in patients with Neuropathic pain. Neuropathic pain, or pain caused by abnormal activity of sensory neurons, remains undertreated. Post herpetic neuralgia (PHN), which is commonly referred to as post-shingles pain, is the most useful disease to study when investigating the efficacy of pain relievers for Neuropathic pain. Therefore, this study will primarily involve patients with PHN. The hypothesis in this study is that etoricoxib efficacy is superior to that of placebo.

Official Title
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An Enriched Enrollment, Double-Blind, Placebo-Controlled, Parallel Group, Randomized Withdrawal Trial to Evaluate the Efficacy, Tolerability and Safety of Etoricoxib (Arcoxia) in Patients With Moderate to Severe Neuropathic Pain

Conditions
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Postherpetic Neuralgia, Neuralgia

Intervention / Treatment
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* Drug: Etoricoxib
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be a man or a non-pregnant, non-lactating woman 18 years and older. Women of childbearing potential should be willing to use an acceptable birth control method (at the investigator's discretion) during the study to avoid pregnancy. Have voluntarily provided written informed consent. Be able to speak, read, write, and understand English, understand the consent form, complete study related procedures, and communicate with the study staff. Have a clinical diagnosis of PHN by history or objective findings in the opinion of the Investigator for a minimum of 6 months. If the patient pool needs to be expanded to other neuropathic conditions, patients must meet the same criteria of patients with PHN and in addition must have a clinical diagnosis of peripheral diabetic neuropathy (PDN), idiopathic sensory neuropathy (ISN) or small fiber predominant neuropathy (SFN) by history or clinical findings in the opinion of the investigator for a minimum of 6 months. Have a pain intensity score averaging ≥3 on a 0-10 NRS for average daily recall over past 24 hours (at Visit 1) Be, in the opinion of the investigator, in generally good health (other than PHN) at screening, based upon the results of a medical history, physical examination and laboratory analysis Exclusion Criteria: Are pregnant and/or lactating Have been diagnosed as having any inflammatory arthritis, gout, pseudo-gout, Paget's disease, fibromyalgia or any chronic pain syndrome that in the Investigator's opinion would interfere with the assessment of pain and other symptoms of PHN Have evidence for multiple causes of pain in the neuropathic pain area, such as lumbar radiculopathy in an area of lumbosacral PHN Have any bodily moderate to severe pain (e.g., osteoarthritis) that could confound assessment or self-evaluation of pain due to PHN Use NSAID compounds (oral and topical) within 1 week of study and for the duration of the study Use opioids including tramadol within 1 week of study and for the duration of the study. (Other NP medications are allowed, provided that the doses have been stable for at least one month prior to Visit 1) Have had neuro-ablation or neurosurgical intervention for their PHN Have received nerve block or intrathecal analgesia within 6 weeks of study Have a history of congestive heart failure, unstable coronary artery disease, stroke, or uncontrolled hypertension Have a history of significant gastrointestinal disease, including active gastro-duodenal ulcerations, perforations, or bleeds Have abnormal clinical laboratory test results or vital signs unless deemed not clinically significant by the investigator Have skin lesions or damage in the area where BSTK measurements are conducted (only applicable to PHN patients) Are undergoing active treatment for cancer, are known to be infected by HIV, or are being acutely and intensively immunosuppressed following transplantation Have a history of alcohol or other substance abuse (not including nicotine or tobacco) within five years Known to have a condition that in the investigator's judgment precludes participation in the study Have a significant psychiatric disorder in the opinion of the Investigator. Have received an investigational drug or have used an investigational device in the 30 days prior to study entry Have previously been admitted to this study Are allergic to Arcoxia.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Etoricoxib<br>The study will use an Enriched Enrollment Randomized Withdrawal (EERW) design consisting of a 2-week open-label enrichment phase, during which subjects will receive etoricoxib. Patients who experience at least a 30% reduction in pain intensity will be randomized to either continued treatment with etoricoxib 90 mg qd or matching placebo (at a 1:1 ratio) for 4 weeks. | Drug: Etoricoxib<br>* 90mg Tablet QD at 10:00a.m.<br>* Other names: Arcoxia;|
| Placebo Comparator: Placebo<br>The study will use an Enriched Enrollment Randomized Withdrawal (EERW) design consisting of a 2-week open-label enrichment phase, during which subjects will receive etoricoxib, followed by a 4-week randomized, double-blind, placebo-controlled treatment phase, during which subjects will receive either etoricoxib or placebo. | Drug: Placebo<br>* One tablet QD at 10:00a.m.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Efficacy Failure | To compare the efficacy of etoricoxib to placebo in reducing pain intensity in patients with NP, as measured by Time to Efficacy Failure during the Double-Blind Period. | 28 Days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate the efficacy of etoricoxib in NP during the Open-Label and the Double-Blind Periods |  | 42 Days | 
| Time to efficacy failure by PHN sub-group based on sensory testing results |  | 42 Days | 
| Safety as assessed by adverse events, serious adverse events, and vital signs |  | 56 Days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Postherpetic neuralgia, Neuropathic pain, Etoricoxib