Low-dose Naltrexone for Bladder Pain Syndrome

Study Overview
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Brief Summary
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Interstitial cystitis/Bladder Pain Syndrome (IC/PBS) is a constellation of symptoms of pelvic discomfort that includes both bladder-related pain as well as urinary frequency, urgency, and nocturia in the absence of an identifiable etiology that affects likely more than 5.4 million patients in the United States. There is a significant overlap in patients with IC/PBS and those with fibromyalgia and chronic pelvic pain syndrome. Low-dose naltrexone (LDN) has been shown to be effective for the treatment of chronic pain conditions. The primary aim of this study is to evaluate if LDN improves pain scores and lower urinary tract symptoms in patients with IC/PBS. A secondary aim is to show that it has a low adverse event profile.

Official Title
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Low-dose Naltrexone for Bladder Pain Syndrome: A Randomized Placebo-controlled Prospective Pilot Trial

Conditions
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Bladder Pain Syndrome, Interstitial Cystitis

Intervention / Treatment
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* Drug: Naltrexone
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women with non-Hunner and Hunner lesion disease Meeting AUA definition of BPS: An unpleasant sensation (pain, pressure, discomfort) perceived to be related to the urinary bladder associated with lower urinary tract symptoms of greater than 6 weeks duration in the absence of infection or other identifiable cause. Stable treatment for 1 month 7-day maximum of pain scores at least 4/10 on the numerical rating scale of pain in the bladder/pelvic area. Urinary frequency 8 or higher while awake. Nocturia 2 or higher. BPIC-SS 19. Agreement to not take opioids through the duration of the trial Exclusion Criteria: Substance Use Disorder Diagnosis including Opioid Use Disorder Diagnosis Known allergy to naltrexone or naloxone Participation in another clinical trial Current or planned pregnancy, or breastfeeding Chronic pain in another location of the body that is more severe than that related to BPS. Any intravesical instillation in last 8 weeks If on Elmiron, stable dose for last 3 months If on amitriptyline, stable dose for last 3 months Any botox within last 6 months Treatment for Hunners in the last 6 months Any new Interstim settings within last 3 months Any new pelvic floor physical therapy in last 12 weeks Any change in or new OTC meds over last 2 months. Any pain interventions in the preceding 6 weeks (epidural steroid injection, sympathetic block, peripheral nerve block, lumbar medial branch blocks) Opioids chronically for IC/BPS in the past unless have been off for 1 year Recent short-term (within one week of enrollment) opioid use for flairs No documented cystoscopy in the last 5 years

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
Interventional Model Description: Randomized placebo-controlled pilot study
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Low-dose naltrexone<br>4.5mg of naltrexone to be taken one hour prior to bedtime nightly for 8 weeks. | Drug: Naltrexone<br>* 4.5mg tab (low-dose) nightly<br>|
| Placebo Comparator: Placebo<br>Placebo tablet (sugar-pill) to be taken one hour prior to bedtime nightly for 8 weeks. | Drug: Placebo<br>* 1 tab nightly<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The proportion of subjects in the LDN and placebo groups that are responders with greater than 20% reductions in 7-day average of worst daily Numeric Rating Scale of Pain scores after 8 weeks of treatment. |  | Will compare pre-intervention to week 8. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Brief Pain Inventory Score |  | At pre-intervention to week 8. | 
| Change in average frequency and nocturia during a 5-day voiding diary |  | At pre-intervention to week 8. | 
| Change in Bladder Pain/Interstitial Cystitis Symptom Score |  | At pre-intervention to week 8 | 
| Change in O'Leary Sant symptom scores |  | At pre-intervention to week 8 | 
| Change in O'Leary Sant Problem Indices scores |  | At pre-intervention to week 8 | 
| Change in Global response assessment scale score |  | At pre-intervention to week 8 | 
| Change in PROMIS pain behavior score |  | At pre-intervention to week 8 | 
| Change in PROMIS physical function score |  | At pre-intervention to week 8 | 
| Change in PROMIS sleep dysfunction score |  | At pre-intervention to week 8 | 
| Change in PROMIS Sleep-Related Impairment |  | At pre-intervention to week 8 | 
| Change in PROMIS pain interference score |  | At pre-intervention to week 8 | 
| Change in PROMIS fatigue score |  | At pre-intervention to week 8 | 
| Change in PROMIS anxiety score |  | At pre-intervention to week 8 | 
| Change in PROMIS depression score |  | At pre-intervention to week 8 |