Comparison of the Effects of Tapentadol and Oxycodone on Gastrointestinal and Colonic Transit in Humans

Study Overview
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Brief Summary
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Tapentadol is FDA approved for the treatment of moderate to severe acute pain. Due to the dual mechanism of action as an opioid agonist and norepinephrine reuptake inhibitor, there is potential for off label use in chronic pain. Tapentadol is a new molecular entity that is structurally similar to tramadol. Tapentadol is a centrally-acting analgesic with a dual mode of action as an agonist at the mu-opioid receptor and as a norepinephrine reuptake inhibitor. These two actions are synergistic in pain relief. While its action reflects aspects of tramadol and morphine, its ability to control pain is more on the order of hydrocodone and oxycodone. Its dual mode of action provides analgesia at similar levels of more potent narcotic analgesics such as hydrocodone, oxycodone, and meperidine with a more tolerable side effect profile. Clinical studies showed that tapentadol effectively relieves moderate to severe pain in various pain care settings. In addition, it was reported to be associated with significantly fewer treatment discontinuations due to a significantly lower incidence of gastrointestinal-related adverse events compared with equivalent doses of oxycodone. The combination of these reduced treatment discontinuation rates and tapentadol efficacy for the relief of moderate to severe nociceptive and neuropathic pain may offer an improvement in pain therapy by increasing patient compliance with their treatment regimen.

Detailed Description
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Single center, parallel group, randomized controlled trial of tapentadol, oxycodone and placebo effects on gastrointestinal and colonic transit in healthy human volunteers

Official Title
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Comparison of the Effects of Tapentadol and Oxycodone on Gastrointestinal and Colonic Transit in Humans

Conditions
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Effects of 2 Mu-opiates on Gastrointestinal Transit

Intervention / Treatment
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* Drug: Tapentadol
* Drug: Oxycodone
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Healthy volunteers Inclusion criteria Males and non-pregnant, non-breastfeeding females 18-65 years old Exclusion criteria Use of any mu-opioid agent in the last 3 months Structural or metabolic diseases/conditions that affect the gastrointestinal system, or functional gastrointestinal disorders. For screening the shortened screening version of the Bowel Disease Questionnaire (Appendix) will be used to exclude subjects with dyspepsia, irritable bowel syndrome or significant gastrointestinal symptoms. Of 19 questions, participants have to have three or less positives to be eligible to participate. Unable to withdraw medications 48 hours prior to the study : Alter GI transit including laxatives, magnesium or aluminum-containing antacids, prokinetics, erythromycin, narcotics, anticholinergics, tricyclic antidepressants, selective serotonin re-uptake inhibitors (SSRIs) and newer antidepressants. Analgesic drugs including opiates, nonsteroidal anti-inflammatory drugs (NSAIDs), COX 2 inhibitors SSRI NOTE: Low stable doses of thyroid replacement, estrogen replacement, low dose aspirin for cardioprotection and birth control pills or depot injections are permissible. Female subjects who are pregnant or breast feeding. Clinical evidence (including physical exam, ECG, hemoglobin level and review of the medical history) of significant cardiovascular, respiratory, renal, hepatic, gastrointestinal, hematological, neurological, psychiatric, or other disease that interfere with the objectives of the study. Subjects who are considered by the investigator to be alcoholics not in remission or known substance abusers. Subjects who have participated in another clinical study within the past 30 days History of porphyria, renal (creatinine > 1.5mg/dL) or significant liver impairment (transaminases, alkaline phosphatase of gamma-glutamyl transpeptidase (GGT) >2 times upper limit of normal)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Tapentadol<br>75 mg tapentadol tid | Drug: Tapentadol<br>* Subjects received tapentadol immediate release formulation, 75 mg three times per day (tid) for 48 hours.<br>* Other names: Tapentadol brand name: Nucynta;|
| Active Comparator: Oxycodone<br>5 mg oxycodone tid | Drug: Oxycodone<br>* Subjects received oxycodone immediate release formulation, 5 mg three times per day (tid) for 48 hours.<br>* Other names: Roxicodone;|
| Placebo Comparator: Placebo<br>Placebo tid | Drug: Placebo<br>* Subjects received placebo three times per day (tid) for 48 hours.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Colonic Transit, Geometric Center at 24 Hours | The scintigraphic method is used to measure colonic transit. An isotope is adsorbed on activated charcoal particles and delivered to the colon in a delayed release capsule. Anterior and posterior gamma images are taken hourly. The geometric center (GC) is the weighted average of counts in the different colonic regions. The scale ranges from 1 to 5; a high GC implies faster colonic transit, a GC of 1 implies all isotope is in the ascending colon, and a GC of 5 implies all isotope is in the stool. | 24 hours | 
| Gastric Emptying Half-time (t1/2) at 24 Hours |  | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Colonic Geometric Center at 8 and 48 Hours | The scintigraphic method is used to measure colonic transit. An isotope is adsorbed on activated charcoal particles and delivered to the colon in a delayed release capsule. Anterior and posterior gamma images are taken hourly. The geometric center (GC) is the weighted average of counts in the different colonic regions. The scale ranges from 1 to 5; a high GC implies faster colonic transit, a GC of 1 implies all isotope is in the ascending colon, and a GC of 5 implies all isotope is in the stool. | 8 hours, 48 hours | 
| Colonic Filling at 6 Hours | Percent of the radio-labeled meal that reached the colon at 6 hours, indirectly reflecting small bowel transit time. | 6 hours | 
| Ascending Colon Emptying (AC t1/2) | Ascending colon emptying t1/2 will be estimated by power exponential analysis of the proportionate emptying over time of counts from the colon. The primary data for this analysis will be the proportion of decay and depth-corrected counts in the ascending colon on the hourly scans on the first day of transit measurement and the 24 hour data. | Over the first 24 hours after ingestion of the radioisotopically labeled charcoal particles | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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tapentadol, oxycodone, mu-opiate, stomach, small intestine, colon, motility, nausea, constipation