This exploratory, proof-of-concept study is a double-blind (participants and investigators will be blinded), placebo-controlled, randomized, two-arm clinical trial of Marinol \[dronabinol, synthetic Δ9-tetrahydrocannabinol (THC)\] for e endometriosis-associated chronic pelvic pain (endo-CPP) with a 2:1 allocation ratio. Up to 75 subjects will be enrolled in this pilot study and randomized to receive doses of THC (up to 30 mg/day), orally, over 8 weeks. This study will be conducted at a single site; it does not include any stratifications, and there is no interim analysis planned. Notably, the goal is to determine whether there is enough evidence of the safety of THC to support the development of later-phase clinical trials. Thus, detailed developmental plans are contingent on the outcomes of this study.
Endometriosis is a progressive, chronic inflammatory disorder that affects approximately 10% of women of reproductive age, with up to 70% to 90% of patients experiencing pelvic pain symptoms, thereby reducing their quality of life, and decreasing labor productivity. Current standard treatments for endometriosis-associated chronic pelvic pain (endo-CPP) include progestin-based hormonal treatments, such as combined oral contraceptive (OC) pills, gonadotropin-releasing hormone (GnRH) analogs, and laparoscopic surgeries. However, endo-CPP often persists even after laparoscopic excision of endometriosis lesions, indicating that controlling disease progression does not necessarily lead to pain relief. As pain is an important factor in endometriosis, optimal analgesia should be sought, which, to date, has primarily been treated with non-steroidal anti-inflammatory drugs (NSAIDs), metamizole, or, in extreme cases, opioids. However, the response to NSAIDs is often ineffective. Additionally, NSAIDs are associated with a higher risk of gastrointestinal bleeding. As for metamizole, agranulocytosis is the most notorious adverse event, along with metamizole-associated hepatotoxicity. Although opioids are generally not recommended for pain relief in women with endometriosis, opioid prescriptions have been identified for women diagnosed with endometriosis within the past year in the United States (As-Sanie S, 2021). Patients undergoing robotic surgery for endometriosis use over two times as many opioids postoperatively as patients without endometriosis and experience higher perceived postoperative pain. Women with endometriosis have a four-fold greater risk of chronic opioid use compared to those without endometriosis. Opioids are highly addictive, and the use of both synthetic and natural opioids can quickly result in dependence, which includes physical and/or psychological dependence, as well as opioid use disorder. Side effects of opioid medications are generally dose-dependent and include constipation, miosis, sedation, and respiratory depression. However, the efficacy of THC in endo-CPP remains uncertain.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
75
Eligible subjects will be randomized (2:1) to dronabinol or placebo, administered orally. The dose of dronabinol will be titrated such that on Day 1, subjects will take 2.5 mg, twice. On subsequent days patients may gradually increase the total number of doses, by one dose each day, as needed and tolerated until either the optimal dose is achieved, or the dose reaches 30 mg THC per day.
Matching placebo will be prepared and administered in the same manner as the active medication. Titration will occur in a masked fashion such that individuals assigned to placebo undergo a similar perceived titration process.
Baylor College of Medicine
Hosuton, Texas, United States
Pain Intensity
For change in pain intensity from baseline to 8-weeks, the investigators will estimate the mean within each arm using the The Endometriosis Health Profile Questionnaire (EHP-30). 30 point scale ranging from 0 (Never) to 5 (Always).
Time frame: Baseline to 8-weeks
Safety Analysis
AEs will be coded using the most recent version of the Medical Dictionary of Regulatory Activities (MedDRA) preferred terms and will be grouped by system, organ, and class (SOC) designation. The severity, frequency, and relationship of AEs to investigational product will be presented by preferred term by SOC grouping. Listings of each individual AE including start date, stop date, severity, relationship, outcome, and duration will be provided.
Time frame: Baseline to 8-weeks
Analgesic Use Log
Analgesic Use Change in Analgesic Use Log scores Day 1 to 56 Secondary analyses will use proper tests and appropriate statistical methods at a significance level of 0.05 (2-sided).
Time frame: Baseline to 8-weeks
Patient-Reported Outcomes Measurement Information System (PROMIS-29)
The severity of pain will be assessed by the validated scale within the Patient-Reported Outcomes Measurement Information System (PROMIS) is a 29-item profile instrument that can be used to assess seven subscales of health quality of life (QOL) for each of 8 domains-this outcome measure reports one of the 7 domains, anxiety: Physical Function, Anxiety, Depression, Fatigue, Sleep Disturbance, Ability to Participate in Social Roles and Activities, Pain Interference, and Pain Intensity. Responses rage from 5 (Without any difficulty) to 0 (Unable to do) on the Physical Function item, 1 (Never) to 5 (Always) on Anxiety, Depression, Ability to Participate in Social Roles and Activities items, 1 (Not at all) to 5 (Very Much) on the Fatigue, Sleep Disturbance, and Pain Interference items, 0 (No pain) to 10 (Worst Pain Imaginable ) on the Pain Intensity.
Time frame: Baseline to 8-weeks
Profile of Mood States (POMS questionnaire)
Changes in POMS . Scale range is 1 to 5 and describes how the participant feels at the time the assessment is administered. Scale of 1, the lowest score, describes a feeling of Not At All right now for the mood and the scale of 5 gives the highest score representing a feeling of Extremely for the mood.
Time frame: Baseline to 8-weeks
Visual Pain Scale
The Faces Pain Scale, a visual analogue scale (VAS), is self-report measure of pain intensity on the widely accepted 0-to-10 metric.
Time frame: Baseline to 8-weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.