Post hoc analyses of data from a 90-day clinical trial evaluating the tolerability and efficacy of tapentadol immediate release and oxycodone immediate release for the relief of moderate to severe pain in elderly and nonelderly patients

The Effect of Oxycodone on Post-operative Pain and Inflammatory Cytokine Release in Elderly Patients Undergoing Laparoscopic Gastrectomy

Background: To evaluate the effect of oxycodone on post-operative pain and inflammation in elderly patients undergoing laparoscopic gastrectomy. Methods: Sixty patients who were of both sexes, American Society of Anesthesiologists Physical Status (ASA-PS) Class I or II, over 65 years of age and undergoing an elective laparoscopic radical gastrectomy were randomly divided into two groups: an oxycodone group (Group O) including 20 males and 10 females and a sufentanil group (Group S) including 21 males and 9 females. The post-operative analgesia regimen was as follows: 40 mg of parecoxib sodium and 0.1 mg/kg of oxycodone was intravenously injected into Group O before the abdomen closure, while 40 mg of parecoxib sodium and 0.1 μg/kg of sufentanil was injected intravenously into Group S. Both groups were infiltrated with 20 ml of 1% ropivacaine at the end of the operation. The level of serum IL-6 and IL-10 were assayed immediately at the following timepoints: at the conclusion of surgery (T1), 1 h (T2), 6 h (T3), and 24 h (T4) after the completion of the surgery. The numerical rating scale (NRS), the Ramsay sedation score, analgesic-related adverse events, post-operative pulmonary inflammation events and the post-operative stay were recorded. Results: Compared with Group S, the serum IL-6 concentrations of Group O decreased at T₃ and T₄, while the serum IL-10 concentrations increased (P < 0.05). In Group O, the serum IL-6 concentrations at T₃ and T₄ were lower than those at T₁ (P < 0.05). The incidence of post-operative nausea and vomiting (PONV) and pulmonary inflammation in Group O was lower than that in Group S (P < 0.05). At each time point, the NRS of visceral pain in Group O was lower than that in Group S. At 6 and 24 h after extubation, the NRS of incision pain in Group O was lower than that in Group S (P < 0.05). Conclusion: Oxycodone can regulate the level of inflammatory cytokines and reduce post-operative inflammatory response.

Predictive Factors of Opioid-Induced Nausea in Cancer Patients

Approximately 30% of patients experience nausea after initiation of opioid therapy, which can lead to poor quality of life. We aimed to identify risk factors for opioid-induced nausea at the initiation of opioid therapy by conducting a retrospective review of medical records of patients diagnosed by palliative care specialists with solid cancer and pain at the lesion site at Showa University Hospital between June 2005 and June 2011. The primary endpoint was the development of nausea grade ≥1 according to the Common Terminology Criteria for Adverse Events version 4.0 within 48 hours of initiation of opioid therapy. The median age of the 134 enrolled patients was 67.7 (range 28-95) years. Fifty-three percent were male and 44% had gastrointestinal cancer. Furthermore, 22.4% had opioid-induced nausea. Age (odds ratio (OR) 1.74; 95% confidence interval (CI), 1.13-2.69), edema (OR 5.83; 95% CI, 1.22-28.19), and gastrointestinal cancer (OR 2.61, 95% CI 1.07-6.36) were significantly associated with opioid-induced nausea. Prophylactic antiemetics were found to be ineffective.

Opioid Use and Potency Are Associated With Clinical Features, Quality of Life, and Use of Resources in Patients With Gastroparesis

BACKGROUND & AIMS

Many patients with gastroparesis are prescribed opioids for pain control, but indications for opioid prescriptions and the relationship of opioid use to gastroparesis manifestations are undefined. We characterized associations of use of potent vs weaker opioids and presentations of diabetic and idiopathic gastroparesis.

METHODS

We collected data on symptoms, gastric emptying, quality of life, and health care resource use from 583 patients with gastroparesis (>10% 4-h scintigraphic retention) from the National Institute of Diabetes and Digestive and Kidney Diseases Gastroparesis Consortium, from January 2007 through November 2016. Patients completed medical questionnaires that included questions about opioid use. The opioid(s) were categorized for potency relative to oral morphine. Symptom severities were quantified by Patient Assessment of Upper Gastrointestinal Disorders Symptoms questionnaires. Subgroup analyses compared patients on potent vs weaker opioids and opioid effects in diabetic vs idiopathic etiologies.

RESULTS

Forty-one percent of patients were taking opioids; 82% of these took potent agents (morphine, hydrocodone, oxycodone, methadone, hydromorphone, buprenorphine, or fentanyl). Abdominal pain was the reason for prescription for 61% of patients taking opioids. Mean scores for gastroparesis, nausea/vomiting, bloating/distention, abdominal pain, and constipation scores were higher in opioid users (P ≤ .05). Opioid use was associated with greater levels of gastric retention, worse quality of life, increased hospitalization, and increased use of antiemetic and pain modulator medications compared with nonusers (P ≤ .03). Use of potent opioids was associated with worse gastroparesis, nausea/vomiting, upper abdominal pain, and quality-of-life scores, and more hospitalizations compared with weaker opioids (tapentadol, tramadol, codeine, or propoxyphene) (P ≤ .05). Opioid use was associated with larger increases in gastric retention in patients with idiopathic vs diabetic gastroparesis (P = .008).

CONCLUSIONS

Opioid use is prevalent among patients with diabetic or idiopathic gastroparesis, and is associated with worse symptoms, delays in gastric emptying, and lower quality of life, as well as greater use of resources. Potent opioids are associated with larger effects than weaker agents. These findings form a basis for studies to characterize adverse outcomes of opioid use in patients with gastroparesis and to help identify those who might benefit from interventions to prevent opioid overuse.

Tapentadol Extended Release in the Treatment of Severe Chronic Low Back Pain and Osteoarthritis Pain

Tapentadol is a novel pain reliever with apparently synergistic dual mechanisms of action, capable of addressing both nociceptive and neuropathic components of chronic pain. As an effective analgesic with good tolerability, tapentadol may be appropriate for patients suffering from severe chronic pain associated with low back pain (LBP) or osteoarthritis (OA). Efficacy studies of tapentadol in populations of patients with severe chronic LBP or OA pain suggest that tapentadol is non-inferior to oxycodone. Its tolerability, especially with respect to gastrointestinal (GI) side effects, may be better than that of other strong opioids in clinical trials and analyses of multiple trials. Patient satisfaction with tapentadol extended release for chronic noncancer pain syndromes is good. Although tapentadol has an opioid component with abuse liability, it appears to be a difficult opioid for tampering with less appeal to abusers than other opioids. For patients with severe LBP and OA pain, tapentadol appears to hold promise as a safe, effective therapeutic option.

Review of Post-Marketing Safety Data on Tapentadol, a Centrally Acting Analgesic

Introduction

Tapentadol is a centrally acting analgesic that has been available for the management of acute and chronic pain in routine clinical practice since 2009.

Methods

This is the first integrated descriptive analysis of post-marketing safety data following the use of tapentadol in a broad range of pain conditions relating to the topics overall safety, dose administration above approved dosages, administration during pregnancy, serotonin syndrome, respiratory depression, and convulsion. The data analyzed pertain to spontaneous reports from healthcare and non-healthcare professionals and were put in the context of safety information known from interventional and non-interventional trials.

Results

The first years of routine clinical practice experience with tapentadol have confirmed the tolerability profile that emerged from the clinical trials. Moreover, the reporting of expected side effects such as respiratory depression and convulsion was low and no major risks were identified. The evaluation of available post-marketing data did not confirm the theoretical risk of serotonin syndrome nor did it reveal unexpected side effects with administration of higher than recommended doses.

Conclusion

More than 8 years after its first introduction, the favorable overall safety profile of tapentadol in the treatment of various pain conditions is maintained in the general population.

Funding

Grünenthal GmbH.

Electronic supplementary material

The online version of this article (10.1007/s12325-017-0654-0) contains supplementary material, which is available to authorized users.

Nanoconjugated NAP as a Potent and Periphery Selective Mu Opioid Receptor Modulator To Treat Opioid-Induced Constipation

Opioids are the mainstay for cancer and noncancer pain management. However, their use is often associated with multiple adverse effects. Among them, the most common and persistent one is probably opioid-induced constipation (OIC). Periphery selective opioid antagonists may alleviate the symptoms of OIC without compromising the analgesic effects of opioids. Recently our laboratories have identified one novel lead compound, 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-[(4'-pyridyl)acetamido]morphinan (NAP), as a peripherally selective mu opioid receptor ligand carrying subnanomolar affinity to the mu opioid receptor and over 100-folds of selectivity over both the delta and kappa opioid receptors, with reasonable oral availability and half-life, and potential to treat OIC. Nanoparticle-based drug delivery systems are now widely considered due to their technological advantages such as good stability, high carrier capacity, low therapeutic side effects, etc. Herein we report nanoparticle supported NAP as a potential candidate for OIC treatment with improved peripheral selectivity over the original lead compound NAP.

Opioids and GI Motility-Friend or Foe?

OPINION STATEMENT

The use of opioids for the treatment of chronic non-cancer pain is growing at an alarming rate. Opioid-induced bowel dysfunction (OBD) is a common adverse effect of long-term opioid treatment manifesting as constipation, nausea, and vomiting. These effects are primarily mediated by peripheral μ-opioid receptors with resultant altered GI motility and function. As a result, patients may present with opioid-induced constipation (OIC), opioid-induced nausea and vomiting (OINV), and/or narcotic bowel syndrome (NBS). This often leads to decreased quality of life and in many cases, discontinuation of opioid therapy. There is limited evidence to support the use of traditional anti-emetics and laxatives in the treatment of OBD. Tapering the dose of opioids, switching to transdermal application, opioid rotation, or dual-action opioids, such as tapentadol, may be helpful in the treatment of OBD. Novel agents, such as peripherally acting μ-opioid receptor antagonists which target the cause of OIC, show promise in the treatment of OBD and should be considered when conventional laxatives fail. This chapter will review the pathophysiology of OBD, including OINV and OIC, and treatment options available.

Improving acute pain management in emergency medicine

Undertreatment of pain (oligoanalgesia) in the emergency department is common, and it negatively impacts patient care. Both failure of appropriate pain assessment and the potential for unsafe analgesic use contribute to the problem. As a result, achieving satisfactory analgesia while minimizing side effects remains particularly challenging for emergency physicians, both in the emergency department and after a patient is discharged. Improvements in rapid pain assessment and in evaluation of noncommunicative populations may result in a better estimation of which patients require analgesia and how much pain is present. New formulations of available treatments, such as rapidly absorbed, topical, or intranasal nonsteroidal anti-inflammatory drug formulations or intranasal opioids, may provide effective analgesia with an improved risk-benefit profile. Other pharmacological therapies have been shown to be effective for certain pain modalities, such as the use of antidepressants for musculoskeletal pain, γ-aminobutyric acid agonists for neuropathic and postsurgical pain, antipsychotics for headache, and topical capsaicin for neuropathic pain. Nonpharmacological methods of pain control include the use of electrical stimulation, relaxation therapies, psychosocial/manipulative therapies, and acupuncture. Tailoring of available treatment options to specific pain modalities, as well as improvements in pain assessment, treatment options, and formulations, may improve pain control in the emergency department setting and beyond.

Evaluation of the cost-effectiveness of buprenorphine in treatment of chronic pain using competing EQ-5D weights

Background and aims

Chronic pain is a life altering condition and common among elderly persons. The 7-day buprenorphine patch could be a suitable treatment for managing chronic pain of moderate severity in elderly patients in Sweden.

The objective of this analysis was to investigate the cost-effectiveness of the 7-day buprenorphine patch, versus no treatment, in patients >50 years old who suffer from moderate pain in a health economic perspective. An additional aim was to evaluate how the cost-effectiveness is affected by the choice of EQ-5D weights.

Methods

The annual treatment cost and the potential gains in health-related quality of life (HRQoL) of buprenorphine, compared to no treatment, were evaluated. Original EQ-5D data were collected from four clinical reference studies at baseline and at the final visit. Treatment effects on HRQoL were then assessed using both UK and Swedish EQ-5D weights. Annual treatment costs were calculated based on costs of physician visits and pharmaceuticals.

The optimal treatment dose was 10-15 μg/h and the analysis was hence performed on both a 10- and a 15 μg/h buprenorphine patch.

Results

The analysis of buprenorphine treatment resulted in improved HRQoL in all reference studies, irrespective of choice of EQ-5D weight set. The change in quality adjusted life years (QALYs) varied with a gain of 0.042-0.118 using the UK weights and 0.020-0.051 with the Swedish weights. The average annual treatment cost was SEK14454 for the 10μg/h patch and SEK17 017 for the 15 μg/h patch, while cost for the no-treatment alternative was SEK 9 960. The base case incremental cost-effectiveness ratios (ICER) with the UK weights were SEK 40000-SEK 170000 and SEK 90000-SEK 350000 when applying the Swedish weights. The corresponding ICER-span in the sensitivity analysis was SEK 15 000-SEK 400 000 when applying the UK weights and SEK 30 000-SEK 840 000 with the Swedish weights (SEK 100 is about €11).

Conclusions

The results imply that the 7-day buprenorphine patch may be a cost-effective treatment of moderate chronic pain in patients over 50 years of age. The UK and the Swedish EQ-5D weights generated vastly different HRQoL estimates but buprenorphine remains cost-effective regardless choice of weight set.

Toward a systematic approach to opioid rotation

Patients requiring chronic opioid therapy may not respond to or tolerate the first opioid prescribed to them, necessitating rotation to another opioid. They may also require dose increases for a number of reasons, including worsening disease and increased pain. Dose escalation to restore analgesia using the primary opioid may lead to increased adverse events. In these patients, rotation to a different opioid at a lower-than-equivalent dose may be sufficient to maintain adequate tolerability and analgesia. In published trials and case series, opioid rotation is performed either using a predetermined substitute opioid with fixed conversion methods, or in a manner that appears to be no more systematic than trial and error. In clinical practice, opioid rotation must be performed with consideration of individual patient characteristics, comorbidities (eg, concurrent psychiatric, pulmonary, renal, or hepatic illness), and concurrent medications, using flexible dosing protocols that take into account incomplete opioid cross-tolerance. References cited in this review were identified via a search of PubMed covering all English language publications up to May 21, 2013 pertaining to opioid rotation, excluding narrative reviews, letters, and expert opinion. The search yielded a total of 129 articles, 92 of which were judged to provide relevant information and subsequently included in this review. Through a review of this literature and from the authors’ empiric experience, this review provides practical information on performing opioid rotation in clinical practice.

Oral or transdermal opioids for osteoarthritis of the knee or hip

BACKGROUND

Osteoarthritis is the most common form of joint disease and the leading cause of pain and physical disability in older people. Opioids may be a viable treatment option if people have severe pain or if other analgesics are contraindicated. However, the evidence about their effectiveness and safety is contradictory. This is an update of a Cochrane review first published in 2009.

OBJECTIVES

To determine the effects on pain, function, safety, and addiction of oral or transdermal opioids compared with placebo or no intervention in people with knee or hip osteoarthritis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and CINAHL (up to 28 July 2008, with an update performed on 15 August 2012), checked conference proceedings, reference lists, and contacted authors.

SELECTION CRITERIA

We included randomised or quasi-randomised controlled trials that compared oral or transdermal opioids with placebo or no treatment in people with knee or hip osteoarthritis. We excluded studies of tramadol. We applied no language restrictions.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate. We calculated standardised mean differences (SMDs) and 95% confidence intervals (CI) for pain and function, and risk ratios for safety outcomes. We combined trials using an inverse-variance random-effects meta-analysis.

MAIN RESULTS

We identified 12 additional trials and included 22 trials with 8275 participants in this update. Oral oxycodone was studied in 10 trials, transdermal buprenorphine and oral tapentadol in four, oral codeine in three, oral morphine and oral oxymorphone in two, and transdermal fentanyl and oral hydromorphone in one trial each. All trials were described as double-blind, but the risk of bias for other domains was unclear in several trials due to incomplete reporting. Opioids were more beneficial in pain reduction than control interventions (SMD -0.28, 95% CI -0.35 to -0.20), which corresponds to a difference in pain scores of 0.7 cm on a 10-cm visual analogue scale (VAS) between opioids and placebo. This corresponds to a difference in improvement of 12% (95% CI 9% to 15%) between opioids (41% mean improvement from baseline) and placebo (29% mean improvement from baseline), which translates into a number needed to treat (NNTB) to cause one additional treatment response on pain of 10 (95% CI 8 to 14). Improvement of function was larger in opioid-treated participants compared with control groups (SMD -0.26, 95% CI -0.35 to -0.17), which corresponds to a difference in function scores of 0.6 units between opioids and placebo on a standardised Western Ontario and McMaster Universities Arthritis Index (WOMAC) disability scale ranging from 0 to 10. This corresponds to a difference in improvement of 11% (95% CI 7% to 14%) between opioids (32% mean improvement from baseline) and placebo (21% mean improvement from baseline), which translates into an NNTB to cause one additional treatment response on function of 11 (95% CI 7 to 14). We did not find substantial differences in effects according to type of opioid, analgesic potency, route of administration, daily dose, methodological quality of trials, and type of funding. Trials with treatment durations of four weeks or less showed larger pain relief than trials with longer treatment duration (P value for interaction = 0.001) and there was evidence for funnel plot asymmetry (P value = 0.054 for pain and P value = 0.011 for function). Adverse events were more frequent in participants receiving opioids compared with control. The pooled risk ratio was 1.49 (95% CI 1.35 to 1.63) for any adverse event (9 trials; 22% of participants in opioid and 15% of participants in control treatment experienced side effects), 3.76 (95% CI 2.93 to 4.82) for drop-outs due to adverse events (19 trials; 6.4% of participants in opioid and 1.7% of participants in control treatment dropped out due to adverse events), and 3.35 (95% CI 0.83 to 13.56) for serious adverse events (2 trials; 1.3% of participants in opioid and 0.4% of participants in control treatment experienced serious adverse events). Withdrawal symptoms occurred more often in opioid compared with control treatment (odds ratio (OR) 2.76, 95% CI 2.02 to 3.77; 3 trials; 2.4% of participants in opioid and 0.9% of participants control treatment experienced withdrawal symptoms).

AUTHORS' CONCLUSIONS

The small mean benefit of non-tramadol opioids are contrasted by significant increases in the risk of adverse events. For the pain outcome in particular, observed effects were of questionable clinical relevance since the 95% CI did not include the minimal clinically important difference of 0.37 SMDs, which corresponds to 0.9 cm on a 10-cm VAS.

Medication pain management in the elderly: unique and underutilized analgesic treatment options

BACKGROUND

By 2030, the US population of adults aged ≥65 years will increase by >80%, and these adults will account for nearly 20% of the US population. In this population, the decline of multiple physiologic processes and diseases collectively influence treatment options. Physiologic changes, drug-drug interactions resulting from polypharmacy, and drug-disease interactions combine to make elderly patients more sensitive to the adverse events (AEs) associated with medications, all of which must be considered in drug selection.

OBJECTIVE

This article focuses on select underutilized medication options for analgesia that may provide significant advantages in the elderly population above and beyond commonly prescribed conventional choices.

METHODS

We performed a complete review of the literature using the search terms pain management, elderly, opioids, NSAIDs, topical NSAIDs, levorphanol, buprenorphine transdermal, and tapentadol. Databases searched included PubMed, Google Scholar, Ovid, and Athens. Package inserts were utilized for approval dates, indications, and formulations available. We looked at reviews of agents to identify important studies for consideration that searches may have missed. Pharmacology and pharmacokinetic data were taken from randomized trials focusing in this area. Pivotal Phase III trials were utilized for discussion of clinical trial experience and to summarize efficacy and AEs. For purposes of validity, only peer-reviewed literature was included.

RESULTS

There were limited data that specifically outlined analgesic drug selection and highlighted safer alternatives for the elderly patient based on polypharmacy risks, end-organ deterioration, and/or drug choices that presented less risk. We focused on unique opioid alternatives: levorphanol, which offers several therapeutic advantages similar to methadone but without the pharmacokinetic and drug-interaction pitfalls associated with methadone; tapentadol, associated with significantly less gastrointestinal distress and constipation; and transdermal buprenorphine, an agonist/antagonist with less risk for the toxicities associated with conventional opioids and with compliance benefits. Topical NSAIDs are discussed as a viable therapeutic option. Specific attention to a more desirable tolerability profile, including avoidance of drug interactions, end-organ dysfunction, and gastrointestinal bleed with topical NSAID agents versus their oral counterparts is discussed, including the ability to achieve superior tissue levels for appropriately selected inflammatory conditions.

CONCLUSION

It is incumbent that providers consider these options as part of an analgesic armamentarium in an effort to maximize therapeutic benefit and minimize risks in the increasing elderly patient population.

Opioid induced nausea and vomiting

Opioids are broad spectrum analgesics that are an integral part of the therapeutic armamentarium to combat pain in the palliative care population. Unfortunately, among the adverse effects of opioids that may be experienced along with analgesia is nausea, vomiting, and/or retching. Although it is conceivable that in the future, using combination agents (opioids combined with agents which may nullify emetic effects), currently nausea/vomiting remains a significant issue for certain patients. However, there exists potential current strategies that may be useful in efforts to diminish the frequency and/or intensity of opioid-induced nausea/vomiting (OINV).

Treatment of chronic pain in older people: evidence-based choice of strong-acting opioids

In the treatment of chronic malignant and non-malignant pain, opioids are used as strong analgesics. Frail elderly patients often have multiple co-morbidities and use multiple medicines, leading to an increased risk of clinically relevant drug-drug and drug-disease interactions. Age-related changes and increased frailty may lead to a less predictable drug response, increased drug sensitivity, and potential harmful drug effects. As a result, physicians face a complex task in prescribing medication to elderly patients. In this review, the appropriateness of the strong-acting opioids buprenorphine, fentanyl, hydromorphone, methadone, morphine, oxycodone and tapentadol is determined for use in elderly patients. Evidence-based recommendations for prescribing strong opioids to the frail elderly are presented. A literature search was performed for all individual drugs, using a validated and published set of 23 criteria concerning effectiveness, safety, pharmacokinetics and pharmacodynamics, experience, and convenience in elderly patients. First, information on the criteria was obtained from pharmaceutical reference books and a MEDLINE search. The information obtained on the individual drugs in the class of opioids was compared with the reference drug morphine. Evidence-based recommendations were formulated on the basis of the pros and cons for the frail elderly. Using the set of 23 criteria, no differentiation can be made between the appropriateness of buprenorphine, fentanyl, hydromorphone, morphine and oxycodone for use in elderly patients. Methadone has strong negative considerations in the treatment of chronic pain in the frail elderly. Methadone has a high drug-drug interaction potential and is associated with prolongation of the QT interval and a potential risk of accumulation due to a long elimination half-life. In addition, methadone is difficult to titrate because of its large inter-individual variability in pharmacokinetics, particularly in the frail elderly. Because of a lack of empiric knowledge, the use of tapentadol is not recommended in frail elderly persons. Nevertheless, tapentadol may prove to be a useful analgesic for the treatment of chronic pain in frail elderly persons because of its possible better gastrointestinal tolerability. In the treatment of chronic pain in the frail elderly, the opioids of first choice are buprenorphine, fentanyl, hydromorphone, morphine and oxycodone. In order to improve the convenience for elderly patients, the controlled-release oral dosage forms and transdermal formulations are preferred.

Design, synthesis, and biological evaluation of 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-[(4'-pyridyl)carboxamido]morphinan derivatives as peripheral selective μ opioid receptor Agents

Peripheral selective μ opioid receptor (MOR) antagonists could alleviate the symptoms of opioid-induced constipation (OIC) without compromising the analgesic effect of opioids. However, a variety of adverse effects were associated with them, partially due to their relatively low MOR selectivity. NAP, a 6β-N-4'-pyridyl substituted naltrexamine derivative, was identified previously as a potent and highly selective MOR antagonist mainly acting within the peripheral nervous system. The noticeable diarrhea associated with it prompted the design and synthesis of its analogues in order to study its structure-activity relationship. Among them, compound 8 showed improved pharmacological profiles compared to the original lead, acting mainly at peripheral while increasing the intestinal motility in morphine-pelleted mice (ED(50) = 0.03 mg/kg). The slight decrease of the ED(50) compared to the original lead was well compensated by the unobserved adverse effect. Hence, this compound seems to be a more promising lead to develop novel therapeutic agents toward OIC.

A randomised, placebo-controlled trial comparing the effects of tapentadol and oxycodone on gastrointestinal and colonic transit in healthy humans

BACKGROUND

Tapentadol is a mu-opioid receptor agonist and norepinephrine reuptake inhibitor. In clinical trials, tapentadol provided somatic pain relief comparable to mu-opioids such as oxycodone, with significantly less gastrointestinal adverse effects. The acute effects of tapentadol on gastrointestinal and colonic transit are unclear.

AIM

To compare acute effects of oral tapentadol and oxycodone on gastric, small bowel and colonic transit of solids in 38 healthy human subjects.

METHODS

In a randomised, parallel-group, double-blind, placebo-controlled study of the effects of identical-appearing tapentadol immediate release (IR), 75 mg t.d.s., or oxycodone IR, 5 mg t.d.s., for 48 h, we measured gastric (GE), small bowel (SBT measured as colonic filling at 6 h) and colonic transit by validated scintigraphy. Drug was commenced on the evening before the start of the transit test. The primary endpoints were overall colonic transit (geometric centre, GC) at 24 h and GE half-time (t1/2 ). ancova of transit data included gender or BMI as covariates. Adverse effects were summarised.

RESULTS

At the doses tested, oxycodone and tapentadol significantly delayed GE t1/2 and SBT, but not overall colonic transit, compared to placebo. Transit profiles in all regions were not significantly different between oxycodone and tapentadol at the doses tested. Both oxycodone and tapentadol were associated with nausea and central effects attributable to central opiate effects.

CONCLUSIONS

Tapentadol significantly delayed gastric emptying t1/2 and small bowel transit, similar to oxycodone. These data suggest that acute administration of tapentadol may not have significant advantages over standard mu-opioids, in terms of the potential to avoid upper gastrointestinal motor dysfunction.