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The Analgesic Efficacy of Δ9-THC (Namisol®) in Patients With Persistent Postsurgical Abdominal Pain

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01562483
Recruitment Status : Completed
First Posted : March 23, 2012
Last Update Posted : October 28, 2014
European Union
Information provided by (Responsible Party):
Radboud University

Brief Summary:

Persistent postsurgical abdominal pain (PPAP) is a very difficult to treat pain. This pain can persist for months or even years and significantly diminishes quality of life. The exact underlying cause for this pain persistence is still unclear, which makes its treatment still a challenge. The promising analgesic effects of Δ9-THC in previous research, plus the improved bioavailability of Namisol® in comparison with previous Δ9-THC substances form the basis of the present research proposal.

The current study aims to investigate the analgesic efficacy of Namisol® as add-on analgesic during a long-term treatment (52 days) of persistent postsurgical abdominal pain.

Condition or disease Intervention/treatment Phase
Postsurgical Pain Abdominal Pain Chronic Pain Drug: Tetrahydrocannabinol Drug: Placebo Phase 2

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 36 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: The Analgesic Efficacy of Δ9-THC (Namisol®) in Patients With Persistent Postsurgical Abdominal Pain; a Randomized, Double Blinded, Placebo-controlled, Experiment
Study Start Date : October 2012
Actual Primary Completion Date : June 2014
Actual Study Completion Date : June 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Abdominal Pain
Drug Information available for: Dronabinol

Arm Intervention/treatment
Experimental: delta-9-tetrahydrocannabinol (namisol) Drug: Tetrahydrocannabinol
The add-on treatment consists of two phases: a step-up phase (day 1-5: 3 mg TID; day 6-10: 5 mg TID), and a stable dose phase (day 11-52: 8 mg TID). The dosage may be tapered to at least 5 mg TID, when 8 mg is not tolerated.
Other Names:
  • Namisol
  • Dronabinol

Placebo Comparator: Placebo Drug: Placebo
Identical to the Namisol arm.

Primary Outcome Measures :
  1. Average VAS pain [ Time Frame: Baseline versus day 52 ]
    The primary outcome measure is defined as the reduction in average VAS pain scores at the end of the study (day 50-52) compared to the pre-treatment level between the Namisol® and placebo group, measured by a Visual Analoge Scale (VAS) in a pain diary.

Secondary Outcome Measures :
  1. Electroencephalogram (EEG) [ Time Frame: Baseline versus day 52 ]
    Evoked potentials to noxious electrical stimuli, evoked potentials to auditory stimuli (oddball), and spontaneous brain activity will be measured in the electroencephalogram (EEG).

  2. Quantitative Sensory Testing (QST) [ Time Frame: Baseline versus day 15 and day 52 ]
    Pressure pain thresholds, electrical thresholds, electric wind-up response, and Diffuse Noxious Inhibitory Control (DNIC) will be measured using Quantitative Sensory Testing (QST).

  3. Depression and (pain related) anxiety [ Time Frame: Baseline versus day 52 ]
    Depression and (pain related) anxiety measured by questionnaires.

  4. Pharmacodynamic parameters [ Time Frame: Baseline versus day 15 and day 52 ]
    Pharmacodynamics measured by body sway and questionnaires (VASBond & Lader and VASBowdle)

  5. Safety parameters [ Time Frame: Baseline until follow-up (day 59-61) ]
    • Laboratory
    • Electrocardiogram (ECG)
    • Heart Frequency (HF) / Blood Pressure (BP)
    • Adverse Events (AE)

  6. Quality of life [ Time Frame: Baseline versus day 52 ]
    Quality of life will be evaluated by questionnaires

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Aged 18 years or older
  • Pain should have developed after a surgical procedure
  • Pain duration exceeding 3 months, and average NRS≥3
  • Stable doses intake of analgesics for the past 2 months
  • The patient has been informed about the study, understood the information and signed the informed consent form

Exclusion Criteria:

  • Diagnosed irritated bowel syndrome (IBS) or chronic pancreatitis
  • Patient took cannabinoids on a regular basis for at least one year
  • Patient does not feel a pinprick test in the lower extremities
  • Patient has a body mass index (BMI) above 36,0 kg/m2
  • Patient suffers from serious painful conditions other than chronic pancreatitis
  • Patient has a significant medical disorder that may interfere with the study or may pose a risk for the patient
  • Patient uses any kind of concomitant medication that may interfere with the study or may pose a risk for the patient
  • Patient does not tolerate oral intake of medication or liquids, or is refrained from oral intake because of medical reasons
  • Patient demonstrates clinical relevant deviations in the electrocardiogram (ECG)
  • Patient has an actual moderate to severe renal impairment
  • Patient has an actual moderate to severe hepatic impairment
  • Patient has a presence or history of major psychiatric illness
  • Patient has experienced an epileptic seizure in the past
  • Patient demonstrates clinically significant laboratory abnormalities
  • Patient demonstrates a positive urine drug screen for THC, cocaine, MDMA, and amphetamines
  • Patient demonstrates a positive test result on hepatitis B surface antigen, hepatitis C antibody or HIV antibody test
  • Patient has a history of sensitivity / idiosyncrasy to THC
  • Patient has a known or suspected lactose intolerance
  • Female patient is pregnant or breastfeeding
  • Patient intends to conceive a child during the course of the study
  • Patient participates in another investigational drug study
  • Patient has a clinical significant exacerbation in illness
  • Patient is unwilling or unable to comply with the lifestyle guidelines

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01562483

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Radboud University Nijmegen Medical Centre
Nijmegen, Netherlands, 6500 HB
Sponsors and Collaborators
Radboud University
European Union
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Principal Investigator: Harry van Goor, MD, PhD Radboud University Nijmegen Medical Centre, department of surgery
Publications automatically indexed to this study by Identifier (NCT Number):
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Responsible Party: Radboud University Identifier: NCT01562483    
Other Study ID Numbers: HEEL-2011-03
First Posted: March 23, 2012    Key Record Dates
Last Update Posted: October 28, 2014
Last Verified: October 2014
Keywords provided by Radboud University:
postsurgical pain
abdominal pain
visceral pain
chronic pain
Additional relevant MeSH terms:
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Chronic Pain
Abdominal Pain
Neurologic Manifestations
Signs and Symptoms, Digestive
Physiological Effects of Drugs
Psychotropic Drugs
Analgesics, Non-Narcotic
Sensory System Agents
Peripheral Nervous System Agents
Cannabinoid Receptor Agonists
Cannabinoid Receptor Modulators
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Hormones, Hormone Substitutes, and Hormone Antagonists