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Novel Use of Probenecid to Alleviate Symptoms of Opioid Withdrawal

Primary Purpose

Chronic Pain, Drug Dependence of Morphine Type, Symptom, Withdrawal

Status
Not yet recruiting
Phase
Phase 2
Locations
Study Type
Interventional
Intervention
Probenecid
Sponsored by
University of Calgary
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Chronic Pain

Eligibility Criteria

18 Years - 80 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  1. Adults with chronic pain. Age greater than or equal to 18 years on the day of enrolment.
  2. Subjects are currently taking a daily opioid pain medication and planning to taper the dose.
  3. Participants complete at least one voluntary opioid dose reduction in the twelve-week study period.
  4. Glomerular filtration rate (GFR) > 50 mL/min
  5. Capable of providing informed consent

Exclusion Criteria:

  1. Allergy to probenecid or related drugs
  2. History of uric acid renal calculi, if known to be urate calculi. If unknown type, then any history of renal calculi.
  3. Known G6PD deficiency
  4. Active gout in any joint
  5. Current use of drugs whose exposure may be prolonged, or risk of toxicity increased when used in combination with probenecid:

    1. Penicillins, specifically ampicillin, penicillin G sodium, and piperacillin
    2. Carbapenems, specifically doripenem and meropenem
    3. Lorazepam, midazolam, nitrazepam
    4. Ketorolac
    5. Oseltamivir
    6. Methotrexate
    7. Mycophenolate
  6. Current use of drugs which may mask symptoms of withdrawal:

    a. Clonidine, lofexidine, tizanidine

  7. Current use of drugs which may diminish the effect of probenecid:

    a. High dose salicylates including greater than 325 mg PO daily of acetylsalicylic acid (ASA)

  8. Pregnancy or breastfeeding
  9. Any major comorbid medical condition which might impair follow-up or result in a safety risk to the participant
  10. Participation in another clinical trial investigating a drug, medical device, or a medical procedure during the 30 days prior to enrolment.

    -

Sites / Locations

    Arms of the Study

    Arm 1

    Arm 2

    Arm 3

    Arm Type

    Active Comparator

    Active Comparator

    Placebo Comparator

    Arm Label

    Probenecid 500 mg PO BID

    Probenecid 1000 mg PO BID

    Placebo PO BID

    Arm Description

    Probenecid 500 mg X 1 PO BID and Placebo X 1 PO BID

    Probenecid 500mg X 2 PO BID

    Placebo X 2 PO BID

    Outcomes

    Primary Outcome Measures

    To evaluate tolerability of oral probenecid in patients undergoing voluntary opioid tapering
    Tolerability will be assessed through use of the "SAFTEE-SI questionnaire recorded as a percentage for each of the three group assignments and again in two groups titled "probenecid" and "placebo". Statistical comparisons will be made between groups with regard to the percentage of participants experiencing any given adverse event. (example: rash occurred at a rate of 0% with placebo, 2% with probenecid 500 mg, and 4% with probenecid 1000 mg). Comparisons will also be made between the "probenecid group" and "placebo group" (Example: Blurred vision occurred at a rate of 2% with placebo compared to 4% with probenecid)
    To evaluate acceptability of oral probenecid in patients undergoing voluntary opioid tapering
    Acceptability will be measured by assessing the Percent of patients achieving 80% compliance in each group as measured by returned supply in medication vials.
    To evaluate safety of oral probenecid in patients undergoing voluntary
    Safety will be assessed by the clinical research team who have diagnosed the adverse events which will be recorded as a percentage for each of the three group assignments and again in two groups titled "probenecid" and "placebo". Statistical comparisons will be made between groups with regard to the percentage of participants experiencing any given adverse event. (example: rash occurred at a rate of 0% with placebo, 2% with probenecid 500 mg, and 4% with probenecid 1000 mg). Comparisons will also be made between the "probenecid group" and "placebo group" (Example: Blurred vision occurred at a rate of 2% with placebo compared to 4% with probenecid)

    Secondary Outcome Measures

    To evaluate the feasibility of treatment with probenecid in a patient-directed opioid tapering protocol, in the setting of an interdisciplinary pain clinic
    To evaluate the feasibility of treatment with probenecid in a patient-directed opioid tapering protocol, in the setting of an interdisciplinary pain clinic. The sample size of enrolling 40 subjects over a 3 year period will be be used to evaluate the feasibility of a larger study using a similar protocol.
    To evaluate whether Panx1 gene variants correlate with opioid withdrawal severity and response to probenecid by collecting salivary samples and performing DNA extraction in a small cohort.
    A summary of association analyses between subjects DNA samples will be evaluated to determine PANX1 genetic variants and then analyzed for corellation with the study endpoints (e.g. adverse events, opioid withdrawal) and then be reported by treatment group.

    Full Information

    First Posted
    September 11, 2020
    Last Updated
    May 23, 2023
    Sponsor
    University of Calgary
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    1. Study Identification

    Unique Protocol Identification Number
    NCT04939623
    Brief Title
    Novel Use of Probenecid to Alleviate Symptoms of Opioid Withdrawal
    Official Title
    Novel Use of Probenecid to Alleviate Symptoms of Opioid Withdrawal in People With Chronic Pain Undergoing Voluntary Opioid Tapering: a Pilot Study
    Study Type
    Interventional

    2. Study Status

    Record Verification Date
    May 2022
    Overall Recruitment Status
    Not yet recruiting
    Study Start Date
    June 2, 2023 (Anticipated)
    Primary Completion Date
    December 31, 2025 (Anticipated)
    Study Completion Date
    December 31, 2025 (Anticipated)

    3. Sponsor/Collaborators

    Responsible Party, by Official Title
    Sponsor
    Name of the Sponsor
    University of Calgary

    4. Oversight

    Studies a U.S. FDA-regulated Drug Product
    Yes
    Studies a U.S. FDA-regulated Device Product
    No
    Product Manufactured in and Exported from the U.S.
    Yes
    Data Monitoring Committee
    No

    5. Study Description

    Brief Summary
    The proposed clinical trial will address the problem of opioid withdrawal. Opioids are essential for pain-relief in the short term, but their continued use is associated with a host of adverse effects. People living with chronic pain who were initiated on opioid therapy now find themselves with a major life-changing problem - dependence on opioid medications. Opioid withdrawal symptoms are a key barrier to decreasing or stopping their opioid medication. Currently, there are few medications that ameliorate the symptoms of opioid withdrawal. This problem is a major part of the opioid crisis in Canada, and impacts people across all demographics and socioeconomic status. A misconception is that only individuals with opioid use disorder are susceptible to opioid withdrawal; on the contrary, appropriate use of prescription opioids to manage pain can lead to significant symptoms of opioid withdrawal when it is reduced or stopped. Patients in Alberta who are at risk for opioid withdrawal, either from prescribed use or misuse will be primarily impacted by this trial. The investigators have recently explored the underlying causes of opioid withdrawal and identified an important target in the spinal cord that is responsible for producing withdrawal symptoms in rats and mice. The target, a protein called pannexin-1 (Panx1), is located throughout the body, specifically in the brain and spinal cord. Using sophisticated biochemical, genetic, and pharmacological techniques, the investigators demonstrated how Panx1 on immune cells is implicated in the production of opioid withdrawal symptoms after cessation of fentanyl and morphine in opioid dependent rodents. The investigators then attenuated these symptoms of withdrawal using probenecid, a drug which inherently blocks Panx1 activity. Because probenecid is a safe and clinically available drug, the findings could be immediately translated into clinical therapy to support people who are struggling with the symptoms of opioid withdrawal and provide clinicians with a safe and effective option for caring for this population.
    Detailed Description
    The proposed clinical trial will address the problem of opioid withdrawal. Opioids are essential for pain-relief in the short term, but their continued use is associated with a host of adverse effects. People living with chronic pain who were initiated on opioid therapy now find themselves with a major life-changing problem - dependence on opioid medications. Opioid withdrawal symptoms are a key barrier to decreasing or stopping their opioid medication. Currently, there are few medications that ameliorate the symptoms of opioid withdrawal. This problem is a major part of the opioid crisis in Canada, and impacts people across all demographics and socioeconomic status. A misconception is that only individuals with opioid use disorder are susceptible to opioid withdrawal; on the contrary, appropriate use of prescription opioids to manage pain can lead to significant symptoms of opioid withdrawal when it is reduced or stopped. Patients in Alberta who are at risk for opioid withdrawal, either from prescribed use or misuse will be primarily impacted by this trial. Our team has recently explored the underlying causes of opioid withdrawal and identified an important target in the spinal cord that is responsible for producing withdrawal symptoms in rats and mice. The target, a protein called pannexin-1 (Panx1), is located throughout the body, specifically in the brain and spinal cord. Using sophisticated biochemical, genetic, and pharmacological techniques, the investigators demonstrated how Panx1 on immune cells is implicated in the production of opioid withdrawal symptoms after cessation of fentanyl and morphine in opioid dependent rodents. The investigators then attenuated these symptoms of withdrawal using probenecid, a drug which inherently blocks Panx1 activity. Because probenecid is a safe and clinically available drug, the findings could be immediately translated into clinical therapy to support people who are struggling with the symptoms of opioid withdrawal and provide clinicians with a safe and effective option for caring for this population. Probenecid was initially developed in the early 1950s as a tool to enhance the activity of penicillin and allow for outpatient treatment of various infections. It increases plasma levels and the half-life of weak organic acids (penicillins, cephalosporins, or other beta-lactam antibiotics) by competitively inhibiting their renal tubular secretion. As a result, it became widely used in combination with beta-lactam antibacterial agents. It is still occasionally used today in combination with cefazolin for the treatment of skin and soft tissue infections, and in combination with cefoxitin or doxycycline as an option for outpatient treatment of pelvic inflammatory disease. Probenacid also competitively inhibits active reabsorption of uric acid at the level of the proximal convoluted tubule promoting excretion of uric acid, thereby reducing serum urate concentrations. Probenecid is also used in combination with cidofovir for the prevention of cidofovir-related nephrotoxicity when used to treat cytomegalovirus retinitis in patients with HIV. More recently, the effects of probenecid on serotonin levels and TRPV2 channels has led to speculation about its utility in depression, Parkinson's Disease, and congestive heart failure. The drug is no longer commercially available in Canada but is commercially available as 500 mg tablets in the United States which can be acquired through Health Canada's Special Access Program. Probenecid can, however, be prepared in Canada by compounding pharmacies. The study is a single centre, randomized, double blind, placebo-controlled, 12-week clinical trial meant to study probenecid use among adult participants living with chronic non-cancer pain using opioid drug therapy on a daily basis and planning to voluntarily reduce their dose.

    6. Conditions and Keywords

    Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
    Chronic Pain, Drug Dependence of Morphine Type, Symptom, Withdrawal

    7. Study Design

    Primary Purpose
    Treatment
    Study Phase
    Phase 2
    Interventional Study Model
    Parallel Assignment
    Model Description
    40 participants will be randomized in a 2:2:1 ratio to one of: Probenecid 500 mg PO BID (16 participants) Probenecid 1000 mg PO BID (16 participants) Placebo PO BID (8 participants)
    Masking
    ParticipantInvestigatorOutcomes Assessor
    Masking Description
    Participants will be sequentially randomized. Allocation will be concealed through use of a computer-generated algorithm employing simple randomization without stratification. Participants and the research team will be blinded to group assignment. Randomization will utilize a 2:2:1 ratio (500 mg Probenecid:1000mg Probenecid: placebo).
    Allocation
    Randomized
    Enrollment
    40 (Anticipated)

    8. Arms, Groups, and Interventions

    Arm Title
    Probenecid 500 mg PO BID
    Arm Type
    Active Comparator
    Arm Description
    Probenecid 500 mg X 1 PO BID and Placebo X 1 PO BID
    Arm Title
    Probenecid 1000 mg PO BID
    Arm Type
    Active Comparator
    Arm Description
    Probenecid 500mg X 2 PO BID
    Arm Title
    Placebo PO BID
    Arm Type
    Placebo Comparator
    Arm Description
    Placebo X 2 PO BID
    Intervention Type
    Drug
    Intervention Name(s)
    Probenecid
    Other Intervention Name(s)
    4-(Dipropylsulfamoyl)benzoic acid, Benemid, Probalan
    Intervention Description
    The Investigators aim to recruit 40 participants who will be followed for 12 weeks in duration. Participants will be randomized in a 2:2:1 ratio to one of probenecid 500 mg, 1000 mg, or placebo PO BID for 12 weeks. Justification for use of a non-active placebo comparator includes the fact that this trial is meant to identify tolerability and safety of probenecid in a population of patients living with chronic pain, this will be best measured by comparing to a non-active placebo.
    Primary Outcome Measure Information:
    Title
    To evaluate tolerability of oral probenecid in patients undergoing voluntary opioid tapering
    Description
    Tolerability will be assessed through use of the "SAFTEE-SI questionnaire recorded as a percentage for each of the three group assignments and again in two groups titled "probenecid" and "placebo". Statistical comparisons will be made between groups with regard to the percentage of participants experiencing any given adverse event. (example: rash occurred at a rate of 0% with placebo, 2% with probenecid 500 mg, and 4% with probenecid 1000 mg). Comparisons will also be made between the "probenecid group" and "placebo group" (Example: Blurred vision occurred at a rate of 2% with placebo compared to 4% with probenecid)
    Time Frame
    12 weeks
    Title
    To evaluate acceptability of oral probenecid in patients undergoing voluntary opioid tapering
    Description
    Acceptability will be measured by assessing the Percent of patients achieving 80% compliance in each group as measured by returned supply in medication vials.
    Time Frame
    12 weeks
    Title
    To evaluate safety of oral probenecid in patients undergoing voluntary
    Description
    Safety will be assessed by the clinical research team who have diagnosed the adverse events which will be recorded as a percentage for each of the three group assignments and again in two groups titled "probenecid" and "placebo". Statistical comparisons will be made between groups with regard to the percentage of participants experiencing any given adverse event. (example: rash occurred at a rate of 0% with placebo, 2% with probenecid 500 mg, and 4% with probenecid 1000 mg). Comparisons will also be made between the "probenecid group" and "placebo group" (Example: Blurred vision occurred at a rate of 2% with placebo compared to 4% with probenecid)
    Time Frame
    12 weeks
    Secondary Outcome Measure Information:
    Title
    To evaluate the feasibility of treatment with probenecid in a patient-directed opioid tapering protocol, in the setting of an interdisciplinary pain clinic
    Description
    To evaluate the feasibility of treatment with probenecid in a patient-directed opioid tapering protocol, in the setting of an interdisciplinary pain clinic. The sample size of enrolling 40 subjects over a 3 year period will be be used to evaluate the feasibility of a larger study using a similar protocol.
    Time Frame
    3 years
    Title
    To evaluate whether Panx1 gene variants correlate with opioid withdrawal severity and response to probenecid by collecting salivary samples and performing DNA extraction in a small cohort.
    Description
    A summary of association analyses between subjects DNA samples will be evaluated to determine PANX1 genetic variants and then analyzed for corellation with the study endpoints (e.g. adverse events, opioid withdrawal) and then be reported by treatment group.
    Time Frame
    3 years

    10. Eligibility

    Sex
    All
    Minimum Age & Unit of Time
    18 Years
    Maximum Age & Unit of Time
    80 Years
    Accepts Healthy Volunteers
    No
    Eligibility Criteria
    Inclusion Criteria: Adults with chronic pain. Age greater than or equal to 18 years on the day of enrolment. Subjects are currently taking a daily opioid pain medication and planning to taper the dose. Participants complete at least one voluntary opioid dose reduction in the twelve-week study period. Glomerular filtration rate (GFR) > 50 mL/min Capable of providing informed consent Exclusion Criteria: Allergy to probenecid or related drugs History of uric acid renal calculi, if known to be urate calculi. If unknown type, then any history of renal calculi. Known G6PD deficiency Active gout in any joint Current use of drugs whose exposure may be prolonged, or risk of toxicity increased when used in combination with probenecid: Penicillins, specifically ampicillin, penicillin G sodium, and piperacillin Carbapenems, specifically doripenem and meropenem Lorazepam, midazolam, nitrazepam Ketorolac Oseltamivir Methotrexate Mycophenolate Current use of drugs which may mask symptoms of withdrawal: a. Clonidine, lofexidine, tizanidine Current use of drugs which may diminish the effect of probenecid: a. High dose salicylates including greater than 325 mg PO daily of acetylsalicylic acid (ASA) Pregnancy or breastfeeding Any major comorbid medical condition which might impair follow-up or result in a safety risk to the participant Participation in another clinical trial investigating a drug, medical device, or a medical procedure during the 30 days prior to enrolment. -
    Central Contact Person:
    First Name & Middle Initial & Last Name or Official Title & Degree
    Tammy Eberle
    Phone
    403-943-9900
    Email
    tammy.eberle@albertahealthservices.ca
    Overall Study Officials:
    First Name & Middle Initial & Last Name & Degree
    Lori Montgomery, MD
    Organizational Affiliation
    University of Calgary
    Official's Role
    Principal Investigator

    12. IPD Sharing Statement

    Plan to Share IPD
    No
    Citations:
    Citation
    1 Beyer, R. H., Wiebelhaus, V. D., Russe, H. F., Peck, H. M., & McKinney, S. E. (1950). Benemid: An anticatabolite; its phar- macological properties. Federation Proceedings, 9, 258.
    Results Reference
    background
    Citation
    Probenecid CPhA Monograph. RxTx. Date of Revision: November 2017. Accessed online at https://www.e-therapeutics.ca on February 21, 2018.
    Results Reference
    background
    PubMed Identifier
    21938493
    Citation
    Robbins N, Koch SE, Tranter M, Rubinstein J. The history and future of probenecid. Cardiovasc Toxicol. 2012 Mar;12(1):1-9. doi: 10.1007/s12012-011-9145-8.
    Results Reference
    background
    Citation
    Benuryl Tablets, Probenecid Tablets. Prescribing Information. Montreal, Quebec. Valeant Canada LP. Date of Revision: September 1, 2004.
    Results Reference
    background
    Links:
    URL
    https://www.e-therapeutics.ca
    Description
    Probenecid CPhA Monograph. RxTx. Date of Revision: February 2014. Accessed online at https://www.e-therapeutics.ca on May 22, 2015.

    Learn more about this trial

    Novel Use of Probenecid to Alleviate Symptoms of Opioid Withdrawal

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