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

Phase 4

Completed

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

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Primary Outcome Measures

Name	Time	Method
Colonic Transit, Geometric Center at 24 Hours	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.
Gastric Emptying Half-time (t1/2) at 24 Hours	24 hours

Secondary Outcome Measures

Name	Time	Method
Colonic Geometric Center at 8 and 48 Hours	8 hours, 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.
Colonic Filling at 6 Hours	6 hours	Percent of the radio-labeled meal that reached the colon at 6 hours, indirectly reflecting small bowel transit time.
Ascending Colon Emptying (AC t1/2)	Over the first 24 hours after ingestion of the radioisotopically labeled charcoal particles	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.