Effect of a Cannabinoid Agonist on Colonic Sensory Functions in Patients With Irritable Bowel Syndrome

Study on the Effect of Cannabinoid Agonist on Gastrointestinal and Colonic Motor and Sensory Functions in Patients With Diarrhea-Predominant Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) affects about 15% of the U.S. population. There are still no effective and safe medications approved for the treatment of abdominal pain associated with bowel symptoms in IBS. This study will investigate the effects of an approved medication, Dronabinol, on the movement of food through the stomach and colon in subjects with a history of diarrhea-predominant Irritable Bowel Syndrome (D-IBS).

Study Overview

• Status: Completed
• Conditions: Irritable Bowel Syndrome
• Intervention / Treatment: Drug: Dronabinol; Drug: Placebo

Detailed Description

Irritable bowel syndrome (IBS) affects about 15% of the U.S. population. Despite increasing understanding of the pathophysiology of IBS, there is no effective medication approved for the treatment of abdominal pain associated with IBS. Cannabinoid receptors (CBR) are on cholinergic neurons in the brain stem, stomach and colon. A cannabinoid receptor 1 (CB1) antagonist, rimonabant, is effective in induction of weight loss; however, the mechanism of this benefit is unclear. Human studies from this lab show that a CBR agonist, dronabinol, inhibits gastric and colonic motility, which may alter appetite or satiation in obesity, and may have potential in the treatment of IBS. The overall focus of the study is on the mechanisms involved in the modulation of gastric and colonic motor and sensory functions by cannabinoid receptors (CBR) in health and in IBS. CB1 receptors are also involved in nociception and in mediating inflammation which are increasingly recognized as being potential pathophysiological mechanisms in IBS.

All participants underwent the following procedures:

1. Documentation of eligibility, screening questionnaires and physical examination, including exclusion of rectal evacuation disorder by standard clinical evaluation within the past 12 months; this was important to ensure the diarrhea was not secondary to "retention with overflow".
2. Bowel preparation with PEG and electrolyte-containing oral colonic lavage solution, followed by a 12 hour fast.
3. Colonic testing of compliance, tone, motility and sensation measurement. Colonic compliance, fasting tone, sensory thresholds and sensory ratings in response to random-order phasic distensions were performed before treatment was administered. Then medication was ingested, and after 60 minutes, the same studies were performed that is compliance, fasting tone, sensory thresholds and sensory ratings in response to random-order phasic distensions. Participants also filled in responses to questionnaires (using 100 mm VAS scales) to describe their sense of tiredness, peace, worry and activity at the time of the measurements of sensation. Finally, participants ingested a standard chocolate 1000 kcal milkshake meal, and postprandial colonic tone and motility were measured for one hour.
4. With appropriate consent, a venous blood sample was obtained from each participant for DNA extraction; this will be used in ongoing pharmacogenomics studies.

Note: This study is related to NCT01253408, part A of the same protocol. Part A explored the effect of dronabinol on gastric and colonic motor functions.

• Study Type: Interventional
• Enrollment (Actual): 75
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 18-75 years
• Positive for IBS symptoms by Rome III criteria
• No prior abdominal surgery (except appendectomy or cholecystectomy
• Score of 10 or less on either Anxiety or Depression on the Hospital Anxiety/Depression Inventory

Exclusion Criteria:

• Patients with significant depression (score of greater than 10 on Hospital Depression Inventory
• Patients with anxiety (score of greater than 10 on Hospital Anxiety Inventory. However, patients on stable doses of selective serotonin inhibitors (SSRIs) or low dose of tricyclic antidepressants will be eligible.

Study Plan

How is the study designed?

Design Details

• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dronabinol 2.5 mg; One dose of dronabinol 2.5 mg was taken orally with water.	Drug: Dronabinol; Dronabinol is a synthetic delta-9-tetrahydrocannabinol, a nonselective cannabinoid agonist. Subjects received one dose of either 2.5 mg or 5 mg orally with water.; Other Names: Marimol
Experimental: Dronabinol 5 mg; One dose of dronabinol 5 mg was taken orally with water.	Drug: Dronabinol; Dronabinol is a synthetic delta-9-tetrahydrocannabinol, a nonselective cannabinoid agonist. Subjects received one dose of either 2.5 mg or 5 mg orally with water.; Other Names: Marimol
Placebo Comparator: Placebo; One dose of placebo was taken orally with water.	Drug: Placebo; Placebo will match study drug; taken as one dose orally with water.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Colonic Compliance at Pressure at Half-Maximum Volume (Pr 1/2)	Colonic compliance is a measure of the "stiffness" of the colon, that is, what pressure was needed to reach half the maximum volume of the colon. After the barostat catheter was inserted in the colon, the catheter was connected to a barostat machine. After an initial conditioning distension to 20 mm Hg, colonic compliance was measured by step-wise inflation with increments of 4 mm Hg up to 64 mm Hg. Colonic compliance was analyzed by a validated linear interpolation method. The pressure at half maximum volume serves as a summary of colonic compliance.	1 hour after drug was ingested

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postprandial Change in Colonic Tone	Colonic tone is a measurement of the volume of the colon. Colonic tone was assessed by noting the changes in the balloon volume in the presence of a constant operating pressure in the balloon (in the barostat-manometric assembly placed in the colon.)	1 hour after ingestion of standard meal
Post-treatment Sensory Threshold for First Perception of Pain	The sensory threshold for first perception of pain was measured by stepwise inflation in increments of 4 mm Hg at 60 second intervals up to a maximum pressure of 64 mm Hg. During this assessment participants were asked to report when they had the first sensation. The investigator recorded the threshold pressure at which the participants reported this sensation.	1 hour after drug was ingested
Post-Treatment Overall Sensory Rating in Response to 16, 24, 32, and 40 mm Hg Distensions	The sensory rating was measured by a 100 mm long Visual Analog Scale (VAS). The VAS does not have any pre-set marks between the extremes of 0 for no pain and 100 mm for extreme pain. The investigator measures the mark made by the participant in mm and records this for the value of pain.	1 hour after drug was ingested
Fasting Colonic Tone	Colonic tone is a measurement of the volume of the colon. Colonic tone was assessed by noting the changes in the balloon volume in the presence of a constant operating pressure in the balloon (in the barostat-manometric assembly placed in the colon.)	After 12 hour fast, before drug administered
Postprandial Colonic Motility Index	Colonic phasic pressure activity is summarized as a motility index (MI)=log_e[number of contractions * sum of amplitudes) + 1]. A normal fasting average motility index (MI) would be about 12. An increase in MI means an increase in the phasic contractions (in contrast to tone) which is measured as a change in volume of the barostat balloon. (Therefore, an increase in MI means that the meal is moving more quickly through the colon.)	1 hour after ingestion of standard meal
Post-treatment Sensory Threshold for First Sensation	The sensory threshold for first sensation was measured by stepwise inflation in increments of 4 mm Hg at 60 second intervals up to a maximum pressure of 64 mm Hg. During this assessment participants were asked to report when they had the first sensation. The investigator recorded the threshold pressure at which the participants reported this sensation.	1 hour after drug was ingested
Post-Treatment Sensory Threshold for First Perception of Gas	The sensory threshold for first perception of gas was measured by stepwise inflation in increments of 4 mm Hg at 60 second intervals up to a maximum pressure of 64 mm Hg. During this assessment participants were asked to report when they had the first sensation. The investigator recorded the threshold pressure at which the participants reported this sensation.	1 hour after drug was ingested

Collaborators and Investigators

• Sponsor: Michael Camilleri
• Collaborators: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); National Center for Research Resources (NCRR)

Publications and helpful links

General Publications

• Wong BS, Camilleri M, Eckert D, Carlson P, Ryks M, Burton D, Zinsmeister AR. Randomized pharmacodynamic and pharmacogenetic trial of dronabinol effects on colon transit in irritable bowel syndrome-diarrhea. Neurogastroenterol Motil. 2012 Apr;24(4):358-e169. doi: 10.1111/j.1365-2982.2011.01874.x. Epub 2012 Jan 30.
• Wong BS, Camilleri M, Busciglio I, Carlson P, Szarka LA, Burton D, Zinsmeister AR. Pharmacogenetic trial of a cannabinoid agonist shows reduced fasting colonic motility in patients with nonconstipated irritable bowel syndrome. Gastroenterology. 2011 Nov;141(5):1638-47.e1-7. doi: 10.1053/j.gastro.2011.07.036. Epub 2011 Jul 29.

Helpful Links

• Link to Part A of this study, results for GI and colonic motor functions, n=36

Study record dates

Study Major Dates

• Study Start: September 1, 2009
• Primary Completion (Actual): December 1, 2011
• Study Completion (Actual): December 1, 2011

Study Registration Dates

• First Submitted: February 5, 2013
• First Submitted That Met QC Criteria: February 5, 2013
• First Posted (Estimate): February 7, 2013

Study Record Updates

• Last Update Posted (Estimate): March 14, 2013
• Last Update Submitted That Met QC Criteria: March 13, 2013
• Last Verified: March 1, 2013

More Information

Terms related to this study

• Keywords: motor; small bowel; sensory; gastric; motility; anandamide; cannabinoid; fatty acid amide hydrolase
• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Disease; Gastrointestinal Diseases; Colonic Diseases, Functional; Colonic Diseases; Intestinal Diseases; Syndrome; Irritable Bowel Syndrome; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Analgesics, Non-Narcotic; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Psychotropic Drugs; Hallucinogens; Cannabinoid Receptor Agonists; Cannabinoid Receptor Modulators; Dronabinol
• Other Study ID Numbers: 08-008314 Part B; UL1RR024150 (U.S. NIH Grant/Contract); R01DK079866 (NIH)