Can a controlled-release oral dose form of oxycodone be used as readily as an immediate-release form for the purpose of titrating to stable pain control?

Pharmacotherapy for Spine-Related Pain in Older Adults

As the population ages, spine-related pain is increasingly common in older adults. While medications play an important role in pain management, their use has limitations in geriatric patients due to reduced liver and renal function, comorbid medical problems, and polypharmacy. This review will assess the evidence basis for medications used for spine-related pain in older adults, with a focus on drug metabolism and adverse drug reactions. A PubMed/OVID search crossing common spine, neck, and back pain terms with key words for older adults and geriatrics was combined with common drug classes and common drug names and limited to clinical trials and age over 65 years. The results were then reviewed with identification of commonly used drugs and drug categories: nonsteroidal anti-inflammatories (NSAIDs), acetaminophen, corticosteroids, gabapentin and pregabalin, antispastic and antispasmodic muscle relaxants, tricyclic antidepressants (TCAs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tramadol, and opioids. Collectively, 138 double-blind, placebo-controlled trials were the focus of the review. The review found a variable contribution of high-quality studies examining the efficacy of medications for spine pain primarily in the geriatric population. There was strong evidence for NSAID use with adjustments for gastrointestinal and renal risk factors. Gabapentin and pregabalin had mixed evidence for neuropathic pain. SNRIs had good evidence for neuropathic pain and a more favorable safety profile than TCAs. Tramadol had some evidence in older patients, but more so in persons aged < 65 years. Rational therapeutic choices based on geriatric spine pain diagnosis are helpful, such as NSAIDs and acetaminophen for arthritic and myofascial-based pain, gabapentinoids or duloxetine for neuropathic and radicular pain, antispastic agents for myofascial-based pain, and combination therapy for mixed etiologies. Tramadol can be well tolerated in older patients, but has risks of cognitive and classic opioid side effects. Otherwise, opioids are typically avoided in the treatment of spine-related pain in older adults due to their morbidity and mortality risk and are reserved for refractory severe pain. Whenever possible, beneficial geriatric spine pain pharmacotherapy should employ the lowest therapeutic doses with consideration of polypharmacy, potentially decreased renal and hepatic metabolism, and co-morbid medical disorders.

Oxycodone for cancer-related pain

BACKGROUND

Many people with cancer experience moderate to severe pain that requires treatment with strong opioids, such as oxycodone and morphine. Strong opioids are, however, not effective for pain in all people, neither are they well tolerated by all people. The aim of this review was to assess whether oxycodone is associated with better pain relief and tolerability than other analgesic options for adults with cancer pain. This is an updated Cochrane review previously published in 2017.

OBJECTIVES

To assess the effectiveness and tolerability of oxycodone by any route of administration for pain in adults with cancer.

SEARCH METHODS

For this update, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE and MEDLINE In-Process (Ovid), Embase (Ovid), Science Citation Index, Conference Proceedings Citation Index - Science (ISI Web of Science), BIOSIS (ISI), and PsycINFO (Ovid) to November 2021. We also searched four trial registries, checked the bibliographic references of relevant studies, and contacted the authors of the included studies. We applied no language, date, or publication status restrictions.

SELECTION CRITERIA

We included randomised controlled trials (parallel-group or cross-over) comparing oxycodone (any formulation or route of administration) with placebo or an active drug (including oxycodone) for cancer background pain in adults by examining pain intensity/relief, adverse events, quality of life, and participant preference.

DATA COLLECTION AND ANALYSIS

Two review authors independently sifted the search, extracted data and assessed the included studies using standard Cochrane methodology. We meta-analysed pain intensity data using the generic inverse variance method, and pain relief and adverse events using the Mantel-Haenszel method, or summarised these data narratively along with the quality of life and participant preference data. We assessed the overall certainty of the evidence using GRADE.

MAIN RESULTS

For this update, we identified 19 new studies (1836 participants) for inclusion. In total, we included 42 studies which enrolled/randomised 4485 participants, with 3945 of these analysed for efficacy and 4176 for safety. The studies examined a number of different drug comparisons. Controlled-release (CR; typically taken every 12 hours) oxycodone versus immediate-release (IR; taken every 4-6 hours) oxycodone Pooled analysis of three of the four studies comparing CR oxycodone to IR oxycodone suggest that there is little to no difference between CR and IR oxycodone in pain intensity (standardised mean difference (SMD) 0.12, 95% confidence interval (CI) -0.1 to 0.34; n = 319; very low-certainty evidence). The evidence is very uncertain about the effect on adverse events, including constipation (RR 0.71, 95% CI 0.45 to 1.13), drowsiness/somnolence (RR 1.03, 95% CI 0.69 to 1.54), nausea (RR 0.85, 95% CI 0.56 to 1.28), and vomiting (RR 0.66, 95% CI 0.38 to 1.15) (very low-certainty evidence). There were no data available for quality of life or participant preference, however, three studies suggested that treatment acceptability may be similar between groups (low-certainty evidence). CR oxycodone versus CR morphine The majority of the 24 studies comparing CR oxycodone to CR morphine reported either pain intensity (continuous variable), pain relief (dichotomous variable), or both. Pooled analysis indicated that pain intensity may be lower (better) after treatment with CR morphine than CR oxycodone (SMD 0.14, 95% CI 0.01 to 0.27; n = 882 in 7 studies; low-certainty evidence). This SMD is equivalent to a difference of 0.27 points on the Brief Pain Inventory scale (0-10 numerical rating scale), which is not clinically significant. Pooled analyses also suggested that there may be little to no difference in the proportion of participants achieving complete or significant pain relief (RR 1.02, 95% CI 0.95 to 1.10; n = 1249 in 13 studies; low-certainty evidence). The RR for constipation (RR 0.75, 95% CI 0.66 to 0.86) may be lower after treatment with CR oxycodone than after CR morphine. Pooled analyses showed that, for most of the adverse events, the CIs were wide, including no effect as well as potential benefit and harm: drowsiness/somnolence (RR 0.88, 95% CI 0.74 to 1.05), nausea (RR 0.93, 95% CI 0.77 to 1.12), and vomiting (RR 0.81, 95% CI 0.63 to 1.04) (low or very low-certainty evidence). No data were available for quality of life. The evidence is very uncertain about the treatment effects on treatment acceptability and participant preference. Other comparisons The remaining studies either compared oxycodone in various formulations or compared oxycodone to different alternative opioids. None found any clear superiority or inferiority of oxycodone for cancer pain, neither as an analgesic agent nor in terms of adverse event rates and treatment acceptability. The certainty of this evidence base was limited by the high or unclear risk of bias of the studies and by imprecision due to low or very low event rates or participant numbers for many outcomes.

AUTHORS' CONCLUSIONS

The conclusions have not changed since the previous version of this review (in 2017). We found low-certainty evidence that there may be little to no difference in pain intensity, pain relief and adverse events between oxycodone and other strong opioids including morphine, commonly considered the gold standard strong opioid. Although we identified a benefit for pain relief in favour of CR morphine over CR oxycodone, this was not clinically significant and did not persist following sensitivity analysis and so we do not consider this important. However, we found that constipation and hallucinations occurred less often with CR oxycodone than with CR morphine; but the certainty of this evidence was either very low or the finding did not persist following sensitivity analysis, so these findings should be treated with utmost caution. Our conclusions are consistent with other reviews and suggest that, while the reliability of the evidence base is low, given the absence of important differences within this analysis, it seems unlikely that larger head-to-head studies of oxycodone versus morphine are justified, although well-designed trials comparing oxycodone to other strong analgesics may well be useful. For clinical purposes, oxycodone or morphine can be used as first-line oral opioids for relief of cancer pain in adults.

Revision of Pharmacological Treatment Recommendations for Cancer Pain: Clinical Guidelines from the Japanese Society of Palliative Medicine

Background: Pain is one of the most common symptoms in cancer patients. The Japanese Society for Palliative Medicine (JSPM) first published its clinical guidelines for the management of cancer pain in 2010. Since then, more research on cancer pain management has been reported, and new drugs have become available in Japan. Thus, the JSPM has now revised the clinical guidelines using a validated methodology. Methods: This guideline was developed through a systematic review, discussion, and the Delphi method, following a formal guideline development process. Results: Thirty-five recommendations were created: 19 for the pharmacological management of cancer pain, 6 for the management of opioid-induced adverse effects, and 10 for pharmacological treatment procedures. Due to the lack of evidence that directly addressed our clinical questions, most of the recommendations had to be based on consensus among committee members and other guidelines. Discussion: It is critical to continue to build high-quality evidence in cancer pain management, and revise these guidelines accordingly.

Controlled Release of Oxycodone as an Opioid Titration for Cancer Pain Relief: A Retrospective Study

BACKGROUND In 2014, a Chinese expert consensus was proposed regarding a titration protocol with controlled-release (CR) oxycodone as a background dose for relieving the moderate to severe cancer pain. This work aimed to summarize its efficacy and safety in our hospital. MATERIAL AND METHODS The Good Pain Management (GPM) protocol comprises a CR morphine or oxycodone given every 12-hours as a background dose and an immediate-release (IR) opioid as a rescue dose. Cancer patients with moderate to severe cancer pain were treated with this protocol, and the successful titration (numerical rating scale [NRS] ≤3 within 3 days) rate was analyzed. SPSS was used for statistical analysis. Differences of variables between opioid intolerant patients and opioid tolerant patients were analyzed using the Mann-Whitney U test. The chi square test was used for comparison of frequencies in different groups. A P-value.

Assessment of prior opioid tolerance among new users of fentanyl transdermal system in FDA's Sentinel System

PURPOSE

Fentanyl transdermal system (FTS) is intended only for patients with prior opioid tolerance. The purpose of this study is to identify the proportion of new FTS users who had evidence of prior opioid tolerance, by dosage strength, in FDA's Sentinel System.

METHODS

We identified new FTS episodes (183-day washout) from 2009 through 2013. Members were <65 years and enrolled in medical and pharmacy coverage for 183 days prior to initial FTS dispensing (index). We assessed the proportion of users with prior tolerance stratified by dosage strength of FTS using four definitions of opioid tolerance: ≥30-mg oxycodone equivalents/day in each of 7 consecutive days immediately prior to index; ≥30-mg oxycodone equivalents/day for any 7 days in the 30 days prior to index (secondary); any dose in each of 7 days in the 7 consecutive days immediately prior to index (tertiary); and any dose for any 7 days in the 30 days prior to index (quaternary).

RESULTS

Of 44 450 episodes of 25 mcg/hr FTS, 37% met the primary definition, and 77% met the quaternary definition. Of 3507 episodes of 100 mcg/hr FTS, 57% and 74% met the primary and quaternary definitions, respectively. Those aged 25 to 34 years had the highest proportion of episodes with prior tolerance; those aged 55 to 64 accounted for more of the episodes overall.

CONCLUSIONS

In Sentinel, many new users of FTS did not have evidence of prior opioid tolerance by the primary definition, ie, the product label definition, which is the minimum standard for the lowest FTS dose (12 mcg/hr), especially at the highest strength (100 mcg/hr). Validation of this metric is warranted, but our findings suggest the need for further prescriber education regarding appropriate prescribing of FTS.

Efficacy, tolerability and acceptability of oxycodone for cancer-related pain in adults: an updated Cochrane systematic review

OBJECTIVES

To assess the efficacy, tolerability and acceptability of oxycodone for cancer pain in adults METHODS: We searched CENTRAL, MEDLINE, MEDLINE In-Process, Embase, SCI, Conference Proceedings Citation Index-Science, BIOSIS, PsycINFO and four trials registries to November 2016.

RESULTS

We included 23 randomised controlled trials with 2144 patients analysed for efficacy and 2363 for safety. Meta-analyses showed no significant differences between controlled-release (CR) and immediate-release oxycodone in pain intensity or adverse events but did show significantly better pain relief after treatment with CR morphine compared with CR oxycodone. However, sensitivity analysis did not corroborate this result. Meta-analyses of the adverse events showed a significantly lower risk of hallucinations after treatment with CR oxycodone compared with CR morphine, but no other differences. The remaining studies either compared oxycodone in various formulations or compared oxycodone to different alternative opioids. None found any clear superiority or inferiority of oxycodone in pain relief or adverse events. The quality of this evidence base was limited by the high/unclear risk of bias of the studies and the low event rates for many outcomes.

CONCLUSIONS

Oxycodone offers similar levels of pain relief and adverse events to other strong opioids. However, hallucinations occurred less with CR oxycodone than with CR morphine, but the quality of this evidence was very low, so this finding should be treated with utmost caution. Our conclusions are consistent with other reviews and suggest that oxycodone can be used first line as an alternative to morphine. However, because it is cheaper, morphine generally remains the first-line opioid of choice.

Oxycodone for cancer-related pain

BACKGROUND

Many people with cancer experience moderate to severe pain that requires treatment with strong opioids, such as oxycodone and morphine. Strong opioids are, however, not effective for pain in all people, neither are they well-tolerated by all people. The aim of this review was to assess whether oxycodone is associated with better pain relief and tolerability than other analgesic options for adults with cancer pain. This is an updated version of the original Cochrane review published in 2015, Issue 2 on oxycodone for cancer-related pain.

OBJECTIVES

To assess the effectiveness and tolerability of oxycodone by any route of administration for pain in adults with cancer.

SEARCH METHODS

For this update, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE and MEDLINE In-Process (Ovid), Embase (Ovid), Science Citation Index, Conference Proceedings Citation Index - Science (ISI Web of Science), BIOSIS (ISI), and PsycINFO (Ovid) to November 2016. We also searched four trial registries, checked the bibliographic references of relevant studies, and contacted the authors of the included studies. We applied no language, date, or publication status restrictions.

SELECTION CRITERIA

We included randomised controlled trials (parallel group or cross-over) comparing oxycodone (any formulation or route of administration) with placebo or an active drug (including oxycodone) for cancer background pain in adults by examining pain intensity/relief, adverse events, quality of life, and participant preference.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the included studies using standard Cochrane methodology. We meta-analysed pain intensity data using the generic inverse variance method, and adverse events using the Mantel-Haenszel method, or summarised these data narratively along with the quality of life and participant preference data. We assessed the overall quality of the evidence using GRADE.

MAIN RESULTS

For this update, we identified six new studies (1258 participants) for inclusion. In total, we included 23 studies which enrolled/randomised 2648 participants, with 2144 of these analysed for efficacy and 2363 for safety. The studies examined a number of different drug comparisons.Pooled analysis of three of the four studies comparing controlled-release (CR) oxycodone to immediate-release (IR) oxycodone showed that the ability of CR and IR oxycodone to provide pain relief were similar (standardised mean difference (SMD) 0.1, 95% confidence interval (CI) -0.06 to 0.26; low quality evidence). Pooled analyses of adverse events showed no significant differences between CR and IR oxycodone for asthenia (risk ratio (RR) 0.58, 95% CI 0.2 to 1.68), confusion (RR 0.78, 95% CI 0.2 to 3.02), constipation (RR 0.71, 95% CI 0.45 to 1.13), dizziness/lightheadedness (RR 0.74, 95% CI 0.4 to 1.37), drowsiness/somnolence (RR 1.03, 95% CI 0.69 to 1.54), dry mouth (RR 1.14, 95% CI 0.48 to 2.75), insomnia (RR 1.04, 95% CI 0.31 to 3.53), nausea (RR 0.85, 95% CI 0.56 to 1.28), nervousness (RR 0.57, 95% CI 0.2 to 1.64), pruritus (RR 1.46, 95% CI 0.65 to 3.25), vomiting (RR 0.66, 95% CI 0.38 to 1.15), and discontinuation due to adverse events (RR 0.6, 95% CI 0.29 to 1.22). The quality of the evidence was very low for all these adverse events. Three of the four studies found similar results for treatment acceptability.Pooled analysis of seven of the nine studies comparing CR oxycodone to CR morphine indicated that pain relief was significantly better after treatment with CR morphine than CR oxycodone (SMD 0.14, 95% CI 0.01 to 0.27; low quality evidence). However, sensitivity analysis did not corroborate this result (SMD 0.12, 95% CI -0.02 to 0.26).Pooled analyses of adverse events showed no significant differences between CR oxycodone and CR morphine for confusion (RR 1.01 95% CI 0.78 to 1.31), constipation (RR 0.98, 95% CI 0.82 to 1.16), dizziness/lightheadedness (RR 0.76, 95% CI 0.33 to 1.76), drowsiness/somnolence (RR 0.9, 95% CI 0.75 to 1.08), dry mouth (RR 1.01, 95% CI 0.8 to 1.26), dysuria (RR 0.71, 95% CI 0.4 to 1.26), nausea (RR 1.02, 95% CI 0.82 to 1.26), pruritus (RR 0.81, 95% CI 0.51 to 1.29), vomiting (RR 0.94, 95% CI 0.68 to 1.29), and discontinuation due to adverse events (RR 1.06, 95% CI 0.43 to 2.6). However, the RR for hallucinations was significantly lower after treatment with CR oxycodone compared to CR morphine (RR 0.52, 95% CI 0.28 to 0.97). The quality of the evidence was very low for all these adverse events. There were no marked differences in treatment acceptability or quality of life ratings.The remaining studies either compared oxycodone in various formulations or compared oxycodone to different alternative opioids. None found any clear superiority or inferiority of oxycodone for cancer pain, neither as an analgesic agent nor in terms of adverse event rates and treatment acceptability.The quality of this evidence base was limited by the high or unclear risk of bias of the studies and by imprecision due to low or very low event rates or participant numbers for many outcomes.

AUTHORS' CONCLUSIONS

The conclusions have not changed since the previous version of this review. The data suggest that oxycodone offers similar levels of pain relief and overall adverse events to other strong opioids including morphine. Although we identified a clinically insignificant benefit on pain relief in favour of CR morphine over CR oxycodone, this did not persist following sensitivity analysis and so we do not consider this important. However, in this updated analysis, we found that hallucinations occurred less often with CR oxycodone than with CR morphine, but the quality of this evidence was very low so this finding should be treated with utmost caution. Our conclusions are consistent with other reviews and suggest that while the reliability of the evidence base is low, given the absence of important differences within this analysis it seems unlikely that larger head to head studies of oxycodone versus morphine are justified, although well-designed trials comparing oxycodone to other strong analgesics may well be useful. For clinical purposes, oxycodone or morphine can be used as first-line oral opioids for relief of cancer pain in adults.

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.

CDC Guideline for Prescribing Opioids for Chronic Pain - United States, 2016

This guideline provides recommendations for primary care clinicians who are prescribing opioids for chronic pain outside of active cancer treatment, palliative care, and end-of-life care. The guideline addresses 1) when to initiate or continue opioids for chronic pain; 2) opioid selection, dosage, duration, follow-up, and discontinuation; and 3) assessing risk and addressing harms of opioid use. CDC developed the guideline using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework, and recommendations are made on the basis of a systematic review of the scientific evidence while considering benefits and harms, values and preferences, and resource allocation. CDC obtained input from experts, stakeholders, the public, peer reviewers, and a federally chartered advisory committee. It is important that patients receive appropriate pain treatment with careful consideration of the benefits and risks of treatment options. This guideline is intended to improve communication between clinicians and patients about the risks and benefits of opioid therapy for chronic pain, improve the safety and effectiveness of pain treatment, and reduce the risks associated with long-term opioid therapy, including opioid use disorder, overdose, and death. CDC has provided a checklist for prescribing opioids for chronic pain (http://stacks.cdc.gov/view/cdc/38025) as well as a website (http://www.cdc.gov/drugoverdose/prescribingresources.html) with additional tools to guide clinicians in implementing the recommendations.

Oxycodone for cancer-related pain

BACKGROUND

Many patients with cancer experience moderate to severe pain that requires treatment with strong opioids, of which oxycodone and morphine are examples. Strong opioids are, however, not effective for pain in all patients, nor are they well-tolerated by all patients. The aim of this review was to assess whether oxycodone is associated with better pain relief and tolerability than other analgesic options for patients with cancer pain.

OBJECTIVES

To assess the effectiveness and tolerability of oxycodone for pain in adults with cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE and MEDLINE In-Process (Ovid), EMBASE (Ovid), Science Citation Index, Conference Proceedings Citation Index - Science (ISI Web of Science), BIOSIS (ISI), PsycINFO (Ovid) and PubMed to March 2014. We also searched Clinicaltrials.gov, metaRegister of Controlled Trials (mRCT), EU Clinical Trials Register and World Health Organization International Clinical Trials Registry Platform (ICTRP). We checked the bibliographic references of relevant identified studies and contacted the authors of the included studies to find additional trials not identified by the electronic searches. No language, date or publication status restrictions were applied to the search.

SELECTION CRITERIA

We included randomised controlled trials (parallel-group or cross-over) comparing oxycodone (any formulation or route of administration) with placebo or an active drug (including oxycodone) for cancer background pain in adults.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted study data (study design, participant details, interventions and outcomes) and independently assessed the quality of the included studies according to standard Cochrane methodology. Where possible, we meta-analysed the pain intensity data using the generic inverse variance method, otherwise these data were summarised narratively along with the adverse event and patient preference data. The overall quality of the evidence for each outcome was assessed according to the GRADE approach.

MAIN RESULTS

We included 17 studies which enrolled/randomised 1390 patients with 1110 of these analysed for efficacy and 1170 for safety. The studies examined a number of different drug comparisons. Four studies compared controlled release (CR) oxycodone to immediate release (IR) oxycodone and pooled analysis of three of these studies showed that the effects of CR and IR oxycodone on pain intensity after treatment were similar (standardised mean difference (SMD) 0.1, 95% confidence interval (CI) -0.06 to 0.26; low quality evidence). This was in line with the finding that none of the included studies reported differences in pain intensity between the treatment groups. Three of the four studies also found similar results for treatment acceptability and adverse events in the IR and CR groups; but one study reported that, compared to IR oxycodone, CR oxycodone was associated with significantly fewer adverse events.Six studies compared CR oxycodone to CR morphine and pooled analysis of five of these studies indicated that pain intensity did not differ significantly between the treatments (SMD 0.14, 95% CI -0.04 to 0.32; low quality evidence). There were no marked differences in adverse event rates, treatment acceptability or quality of life ratings.The remaining seven studies either compared oxycodone in various formulations or compared oxycodone to different alternative opioids. None of them found any clear superiority or inferiority of oxycodone for cancer pain, neither as an analgesic agent nor in terms of adverse event rates and treatment acceptability.The quality of this evidence base was limited by the risk of bias of the studies and by small sample sizes for many outcomes. Random sequence generation and allocation concealment were under-reported, and the results were substantially compromised by attrition with data missing from more than 20% of the enrolled/randomised patients for efficacy and from more than 15% for safety.

AUTHORS' CONCLUSIONS

Overall, the data included within this review suggest that oxycodone offers similar levels of pain relief and adverse events to other strong opioids including morphine, which is commonly considered the gold standard strong opioid. Our conclusions are consistent with other recent reviews and suggest that while the reliability of the evidence base is low, given the absence of important differences within this analysis it seems unlikely that larger head to head studies of oxycodone versus morphine will be justified. This means that for clinical purposes oxycodone or morphine can be used as first line oral opioids for relief of cancer pain.

The effectiveness and risks of long-term opioid therapy for chronic pain: a systematic review for a National Institutes of Health Pathways to Prevention Workshop

BACKGROUND

Increases in prescriptions of opioid medications for chronic pain have been accompanied by increases in opioid overdoses, abuse, and other harms and uncertainty about long-term effectiveness.

PURPOSE

To evaluate evidence on the effectiveness and harms of long-term (>3 months) opioid therapy for chronic pain in adults.

DATA SOURCES

MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, PsycINFO, and CINAHL (January 2008 through August 2014); relevant studies from a prior review; reference lists; and ClinicalTrials.gov.

STUDY SELECTION

Randomized trials and observational studies that involved adults with chronic pain who were prescribed long-term opioid therapy and that evaluated opioid therapy versus placebo, no opioid, or nonopioid therapy; different opioid dosing strategies; or risk mitigation strategies.

DATA EXTRACTION

Dual extraction and quality assessment.

DATA SYNTHESIS

No study of opioid therapy versus no opioid therapy evaluated long-term (>1 year) outcomes related to pain, function, quality of life, opioid abuse, or addiction. Good- and fair-quality observational studies suggest that opioid therapy for chronic pain is associated with increased risk for overdose, opioid abuse, fractures, myocardial infarction, and markers of sexual dysfunction, although there are few studies for each of these outcomes; for some harms, higher doses are associated with increased risk. Evidence on the effectiveness and harms of different opioid dosing and risk mitigation strategies is limited.

LIMITATIONS

Non-English-language articles were excluded, meta-analysis could not be done, and publication bias could not be assessed. No placebo-controlled trials met inclusion criteria, evidence was lacking for many comparisons and outcomes, and observational studies were limited in their ability to address potential confounding.

CONCLUSION

Evidence is insufficient to determine the effectiveness of long-term opioid therapy for improving chronic pain and function. Evidence supports a dose-dependent risk for serious harms.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Impact of morphine, fentanyl, oxycodone or codeine on patient consciousness, appetite and thirst when used to treat cancer pain

BACKGROUND

There is increasing focus on providing high quality care for people at the end of life, irrespective of disease or cause, and in all settings. In the last ten years the use of care pathways to aid those treating patients at the end of life has become common worldwide. The use of the Liverpool Care Pathway in the UK has been criticised. In England the LCP was the subject of an independent review, commissioned by a Health Minister. The Neuberger Review acknowledged that the LCP was based on the sound ethical principles that provide the basis of good quality care for patients and families when implemented properly. It also found that the LCP often was not implemented properly, and had instead become a barrier to good care; it made over 40 recommendations, including education and training, research and development, access to specialist palliative care services, and the need to ensure care and compassion for all dying patients. In July 2013, the Department of Health released a statement that stated the use of the LCP should be "phased out over the next 6-12 months and replaced with an individual approach to end of life care for each patient".The impact of opioids was a particular concern because of their potential influence on consciousness, appetite and thirst in people near the end of life. There was concern that impaired patient consciousness may lead to an earlier death, and that effects of opioids on appetite and thirst may result in unnecessary suffering. This rapid review, commissioned by the National Institute for Health Research, used standard Cochrane methodology to examine adverse effects of morphine, fentanyl, oxycodone, and codeine in cancer pain studies as a close approximation to possible effects in the dying patient.

OBJECTIVES

To determine the impact of opioid treatment on patient consciousness, appetite and thirst in randomised controlled trials of morphine, fentanyl, oxycodone or codeine for treating cancer pain.

SEARCH METHODS

We assessed adverse event data reported in studies included in current Cochrane reviews of opioids for cancer pain: specifically morphine, fentanyl, oxycodone, and codeine.

SELECTION CRITERIA

We included randomised studies using multiple doses of four opioid drugs (morphine, fentanyl, oxycodone, and codeine) in cancer pain. These were taken from four existing or ongoing Cochrane reviews. Participants were adults aged 18 and over. We included only full journal publication articles.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted adverse event data, and examined issues of study quality. The primary outcomes sought were numbers of participants experiencing adverse events of reduced consciousness, appetite, and thirst. Secondary outcomes were possible surrogate measures of the primary outcomes: delirium, dizziness, hallucinations, mood change and somnolence relating to patient consciousness, and nausea, vomiting, constipation, diarrhoea, dyspepsia, dysphagia, anorexia, asthenia, dehydration, or dry mouth relating to appetite or thirst.Comparative measures of harm were known to be unlikely, and we therefore calculated the proportion of participants experiencing each of the adverse events of interest with each opioid, and for all four opioid drugs combined.

MAIN RESULTS

We included 77 studies with 5619 randomised participants. There was potential bias in most studies, with small size being the most common; individual treatment groups had fewer than 50 participants in 60 studies. Participants were relatively young, with mean age in the studies typically between 50 and 70 years. Multiple major problems with adverse event reporting were found, including failing to report adverse events in all participants who received medication, all adverse events experienced, how adverse events were collected, and not defining adverse event terminology or whether a reporting system was used.Direct measures of patient consciousness, patient appetite, or thirst were not apparent. For opioids used to treat cancer pain adverse event incidence rates were 25% for constipation, 23% for somnolence, 21% for nausea, 17% for dry mouth, and 13% for vomiting, anorexia, and dizziness. Asthenia, diarrhoea, insomnia, mood change, hallucinations and dehydration occurred at incidence rates of 5% and below.

AUTHORS' CONCLUSIONS

We found no direct evidence that opioids affected patient consciousness, appetite or thirst when used to treat cancer pain. However, somnolence, dry mouth, and anorexia were common adverse events in people with cancer pain treated with morphine, fentanyl, oxycodone, or codeine.We are aware that there is an important literature concerning the problems that exist with adverse event measurement, reporting, and attribution. Together with the known complications concerning concomitant medication, data collection and reporting, and nomenclature, this means that these adverse events cannot always be attributed unequivocally to the use of opioids, and so they provide only a broad picture of adverse events with opioids in cancer pain. The research agenda includes developing definitions for adverse events that have a spectrum of severity or importance, and the development of appropriate measurement tools for recording such events to aid clinical practice and clinical research.

Candidate metrics for evaluating the impact of prescriber education on the safe use of extended-release/long-acting (ER/LA) opioid analgesics

OBJECTIVE

The objective of this study was to develop metrics to assess opioid prescribing behavior as part of the evaluation of the Extended-Release/Long-Acting (ER/LA) Opioid Analgesic Risk Evaluation and Mitigation Strategies (REMS).

DESIGN

Candidate metrics were selected using published guidelines, examined using sensitivity analyses, and applied to cross-sectional rolling cohorts of Medicare patients prescribed with extended-release oxycodone (ERO) between July 2, 2006 and July 1, 2011. Potential metrics included prescribing opioid-tolerant-only ER/LA opioid analgesics to non-opioid-tolerant patients, prescribing early fills to patients, and ordering drug screens.

RESULTS

Proposed definitions for opioid tolerance were seven continuous days of opioid usage of at least 30 mg oxycodone equivalents, within the 7 days (primary) or 30 days (secondary) prior to first opioid-tolerant-only ERO prescription. Forty-four percent of opioid-tolerant-only ERO episodes met the primary opioid tolerance definition; 56% met the secondary definition. Fills were deemed "early" if a prescription was filled before 70% (primary) or 50% (secondary) of the prior prescription's days' supply was to be consumed. Five percent (primary) and 2% (secondary) of episodes had more than or equal to two early fills during treatment. At least one drug screen was billed in 14% of episodes. Stratified analyses indicated that older patients were less likely to be opioid tolerant at the time of the first opioid-tolerant-only ERO prescription.

CONCLUSIONS

Investigators propose three metrics to monitor changes in prescribing behaviors for opioid analgesics that might be used to evaluate the ER/LA Opioid Analgesics REMS. Low frequencies of patients, particularly those >85 years, were likely to be opioid tolerant prior to receiving prescriptions for opioid-tolerant-only ERO.

Systematic literature review and meta-analysis of the efficacy and safety of prescription opioids, including abuse-deterrent formulations, in non-cancer pain management

OBJECTIVE

This study was conducted to compare safety and efficacy outcomes between opioids formulated with technologies designed to deter or resist tampering (i.e., abuse-deterrent formulations [ADFs]) and non-ADFs for commonly prescribed opioids for treatment of non-cancer pain in adults.

METHODS

PubMed and Cochrane Library databases were searched for opioid publications between September 1, 2001 and August 31, 2011, and pivotal clinical trials from all years; abstracts from key pain conferences (2010-2011) were also reviewed. One hundred and ninety-one publications were initially identified, 68 of which met eligibility criteria and were systematically reviewed; a subset of 16 involved a placebo group (13 non-ADFs vs placebo, 3 ADFs vs placebo) and reported both efficacy and safety outcomes, and were included for a meta-analysis. Summary estimates of standardized difference in mean change of pain intensity (DMCPI), standardized difference in sum of pain intensity difference (DSPID), and odds ratios (ORs) of each adverse event (AE) were computed through random-effects estimates for ADFs (and non-ADFs) vs placebo. Indirect treatment comparisons were conducted to compare ADFs and non-ADFs.

RESULTS

Summary estimates for standardized DMCPI and for standardized DSPID indicated that ADFs and non-ADFs showed significantly greater efficacy than placebo in reducing pain intensity. Indirect analyses assessing the efficacy outcomes between ADFs and non-ADFs indicated that they were not significantly different (standardized DMCPI [0.39 {95% confidence interval (CI) 0.00-0.76}]; standardized DSPID [-0.22 {95% CI -0.74 to 0.30}]). ADFs and non-ADFs both were associated with higher odds of AEs than placebo. Odds ratios from indirect analyses comparing AEs for ADFs vs non-ADFs were not significant (nausea, 0.87 [0.24-3.12]; vomiting, 1.54 [0.40-5.97]; dizziness/vertigo, 0.61 [0.21-1.76]; headache, 1.42 [0.57-3.53]; somnolence/drowsiness, 0.47 [0.09-2.58]; constipation, 0.64 [0.28-1.49]; pruritus 0.41 [0.05-3.51]).

CONCLUSION

ADFs and non-ADFs had comparable efficacy and safety profiles, while both were more efficacious than placebo in reducing pain intensity.

Opioids compared to placebo or other treatments for chronic low-back pain

BACKGROUND

The use of opioids in the long-term management of chronic low-back pain (CLBP) has increased dramatically. Despite this trend, the benefits and risks of these medications remain unclear. This review is an update of a Cochrane review first published in 2007.

OBJECTIVES

To determine the efficacy of opioids in adults with CLBP.

SEARCH METHODS

We electronically searched the Cochrane Back Review Group's Specialized Register, CENTRAL, CINAHL and PsycINFO, MEDLINE, and EMBASE from January 2006 to October 2012. We checked the reference lists of these trials and other relevant systematic reviews for potential trials for inclusion.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that assessed the use of opioids (as monotherapy or in combination with other therapies) in adults with CLBP that were at least four weeks in duration. We included trials that compared non-injectable opioids to placebo or other treatments. We excluded trials that compared different opioids only.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the risk of bias and extracted data onto a pre-designed form. We pooled results using Review Manager (RevMan) 5.2. We reported on pain and function outcomes using standardized mean difference (SMD) or risk ratios with 95% confidence intervals (95% CI). We used absolute risk difference (RD) with 95% CI to report adverse effects.

MAIN RESULTS

We included 15 trials (5540 participants). Tramadol was examined in five trials (1378 participants); it was found to be better than placebo for pain (SMD -0.55, 95% CI -0.66 to -0.44; low quality evidence) and function (SMD -0.18, 95% CI -0.29 to -0.07; moderate quality evidence). Transdermal buprenorphine (two trials, 653 participants) may make little difference for pain (SMD -2.47, 95%CI -2.69 to -2.25; very low quality evidence), but no difference compared to placebo for function (SMD -0.14, 95%CI -0.53 to 0.25; very low quality evidence). Strong opioids (morphine, hydromorphone, oxycodone, oxymorphone, and tapentadol), examined in six trials (1887 participants), were better than placebo for pain (SMD -0.43, 95%CI -0.52 to -0.33; moderate quality evidence) and function (SMD -0.26, 95% CI -0.37 to -0.15; moderate quality evidence). One trial (1583 participants) demonstrated that tramadol may make little difference compared to celecoxib (RR 0.82, 95% CI 0.76 to 0.90; very low quality evidence) for pain relief. Two trials (272 participants) found no difference between opioids and antidepressants for either pain (SMD 0.21, 95% CI -0.03 to 0.45; very low quality evidence), or function (SMD -0.11, 95% -0.63 to 0.42; very low quality evidence). The included trials in this review had high drop-out rates, were of short duration, and had limited interpretability of functional improvement. They did not report any serious adverse effects, risks (addiction or overdose), or complications (sleep apnea, opioid-induced hyperalgesia, hypogonadism). In general, the effect sizes were medium for pain and small for function.

AUTHORS' CONCLUSIONS

There is some evidence (very low to moderate quality) for short-term efficacy (for both pain and function) of opioids to treat CLBP compared to placebo. The very few trials that compared opioids to non-steroidal anti-inflammatory drugs (NSAIDs) or antidepressants did not show any differences regarding pain and function. The initiation of a trial of opioids for long-term management should be done with extreme caution, especially after a comprehensive assessment of potential risks. There are no placebo-RCTs supporting the effectiveness and safety of long-term opioid therapy for treatment of CLBP.

Long-term opioid treatment of chronic nonmalignant pain: unproven efficacy and neglected safety?

BACKGROUND

For the past 30 years, opioids have been used to treat chronic nonmalignant pain. This study tests the following hypotheses: (1) there is no strong evidence-based foundation for the conclusion that long-term opioid treatment of chronic nonmalignant pain is effective; and (2) the main problem associated with the safety of such treatment - assessment of the risk of addiction - has been neglected.

METHODS

Scientometric analysis of the articles representing clinical research in this area was performed to assess (1) the quality of presented evidence (type of study); and (2) the duration of the treatment phase. The sufficiency of representation of addiction was assessed by counting the number of articles that represent (1) editorials; (2) articles in the top specialty journals; and (3) articles with titles clearly indicating that the addiction-related safety is involved (topic-in-title articles).

RESULTS

Not a single randomized controlled trial with opioid treatment lasting >3 months was found. All studies with a duration of opioid treatment ≥6 months (n = 16) were conducted without a proper control group. Such studies cannot provide the consistent good-quality evidence necessary for a strong clinical recommendation. There were profound differences in the number of addiction articles related specifically to chronic nonmalignant pain patients and to opioid addiction in general. An inadequate number of chronic pain-related publications were observed with all three types of counted articles: editorials, articles in the top specialty journals, and topic-in-title articles.

CONCLUSION

There is no strong evidence-based foundation for the conclusion that long-term opioid treatment of chronic nonmalignant pain is effective. The above identified signs indicating neglect of addiction associated with the opioid treatment of chronic nonmalignant pain were present.

Contribution of oxycodone and its metabolites to the overall analgesic effect after oxycodone administration

OBJECTIVE

Oxycodone (OC) is an opioid which exerts its analgesic effect through µ-receptors in the brain. It is metabolized through CYP450 enzymes and some of the metabolites show pharmacological activity. The aim of this investigation is to research the contribution of the metabolites of OC to its overall analgesic effect. A further aim was to elucidate the role of drug-drug interactions and CYP2D6 polymorphism.

RESEARCH DESIGN AND METHODS

The authors performed a literature search to identify published information on: blood concentrations of OC and metabolites, protein binding, blood-brain-barrier behavior and opioid receptor affinity. The authors then calculated the contribution of OC and metabolites to the overall analgesic effect.

RESULTS

OC itself is responsible for 83.02 and 94.76% of the analgesic effect during p.o. and i.v. administration, respectively. Oxymorphone (OM), which has a much higher affinity for the µ-receptor, only plays a minor role (15.77 and 4.52% for p.o. and i.v., respectively). Although the CYP2D6 genotype modulates OM pharmacokinetics, OC remains the major contributor to the overall analgesic effect.

CONCLUSION

This article's calculations demonstrate that OC itself is responsible for the analgesic effect. Although OM and noroxymorphone have much higher µ-receptor affinity than the parent drug, the metabolite concentrations at the site of action are very low. This suggests that there is a minimal analgesic effect from these metabolites.

Is oxycodone efficacy reflected in serum concentrations? A multicenter, cross-sectional study in 456 adult cancer patients

CONTEXT

The relationship between oxycodone and metabolite serum concentrations and clinical effects has not previously been investigated in cancer pain patients.

OBJECTIVES

The aim of this study was to assess whether there is a relationship between oxycodone concentrations and pain intensity, cognitive functioning, nausea, or tiredness in cancer patients. Also, oxymorphone and noroxymorphone contributions to analgesia and the adverse effects of oxycodone were assessed.

METHODS

Four hundred fifty-six cancer patients receiving oxycodone for cancer pain were included. Pain was assessed using the Brief Pain Inventory. The European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire-C30 was used to assess the symptoms of tiredness, nausea, constipation, and depression. Cognitive function was assessed using the Mini-Mental State Examination. Associations were examined by multiple linear or ordinal logistic regressions. Whether patients classified as being a "treatment success" or a "treatment failure" had different serum concentrations of oxycodone or metabolites was assessed using Mann-Whitney U-tests.

RESULTS

Serum concentrations of oxycodone and metabolites were not associated with pain intensity, nausea, tiredness, or cognitive function, with the exception that increased pain intensity was associated with higher oxymorphone concentrations. Patients with poor pain control and side effects had higher serum concentrations of the oxycodone metabolites, noroxycodone and noroxymorphone, compared with those with good pain relief and without side effects.

CONCLUSION

This study of patients receiving oxycodone for cancer pain confirms previous observations that there is most likely no association between serum concentrations of opioid analgesics and clinical effects.

Controlled-release oxycodone tablets after transdermal-based opioid therapy in patients with cancer and non-cancer pain

BACKGROUND AND AIMS

Several publications and guidelines stress the efficacy and safety of opioid-based therapy for cancer and non-cancer pain management. The first point of the World Health Organization (WHO) guidelines recommends that, if possible, analgesics should be given by mouth. This advice fully matches the European Society for Medical Oncology (ESMO) guidelines, which advise that opioids should be titrated to take effect as rapidly as possible. The European Association for Palliative Care (EAPC) guidelines specify that transdermal fentanyl should be administered only in patients with stable analgesic requirements. The aim of this study was to assess the efficacy and influence on the quality of life of controlled- release (CR) oxycodone in patients who had obtained no or only partial pain relief after transdermal (TTD)-based opioid therapy.

METHODS

Forty-one consecutive patients experiencing persistent cancer and non-cancer related pain and in treatment with transdermal- based opioid therapy for at least 5 days were enrolled in this open-label, multicenter observational study. All patients were switched from transdermal to oral opioid therapy with oxycodone CR for 21 days. Pain intensity was rated on a numeric rating scale (NRS) from 0 to 10 (0=no pain, 10=maximum severity). Patients were asked to rate their perceptions on efficacy and pain interference on the quality of life on an NRS from 0 to 10 (0=no interference, 10=maximum interference).

RESULTS

After 3 days with oxycodone CR, pain intensity decreased by 38.83% (p<0.001) and maintained a significant decrease throughout the period (T0-T7: -59.71%, p<0.001; T0-T21: -65.75%, p<0.001). The average daily dose of oxycodone CR increased from 68.75 mg at baseline to 72.39 mg after 7 days and was maintained stable until the study ended. At T0, 56.10% of patients suffered from severe pain (NRS 7- 10); this percentage had decreased to 2.56% at the end of the study. About 7% of patients considered transdermal therapy effective at baseline; after 21 days, 72.22% and 19.44% of patients considered it effective and very effective, respectively. Quality of life improved significantly during the 21 days with the oral treatment (p<0.001).

CONCLUSIONS

Switching from transdermal opioid to oxycodone CR treatment is effective and leads to patients' improved satisfaction and quality of life.

Oxycodone controlled release in cancer pain management

Oral opioids are the treatment of choice for chronic cancer pain. Morphine is the strong opioid of choice for the treatment of moderate to severe cancer pain according to guidelines from the World Health Organization (WHO). This recommendation by the WHO was derived from availability, familiarity to clinicians, established effectiveness, simplicity of administration, and relative inexpensive cost. It was not based on proven therapeutic superiority over other options. Patients who experience inadequate pain relief or intolerable side effects with one opioid may often be successfully treated with another agent or with the same agent administered by a different route. Opioid rotation, or switching to an alternative opioid, helps some patients achieve better pain control with fewer associated adverse effects. Oxycodone is a μ-opioid receptor specific ligand, with clear agonist properties. It is an active potent opioid, which is in part a κ-receptor agonist. Like morphine and other pure agonists, there is no known ceiling to the analgesic effects of oxycodone. The active metabolites of oxycodone (eg, oxymorphone) could be important in oxycodone-mediated analgesia. The main pharmacokinetic difference between oxycodone and morphine is in oral bioavailability. The bioavailability of oxycodone is >60% and the bioavailability of morphine is 20%. Controlled-release oxycodone is absorbed in a bi-exponential fashion. There is a rapid phase with a mean half-life of 37 min, accounting for 38% of the dose, and a slow phase with a half-life of 6.2 h, which accounts for the residual 62%. Oxycodone elimination is impaired by renal failure because there are both an increased volume of distribution and reduced clearance. A lot of studies prove that the efficacy of controlled-release oxycodone in cancer-pain control is at least the same as morphine, immediate-release oxycodone and hydromorphone. Its toxicity profile seems better than that of morphine. There are actually several illustrations of a lower incidence of side-effects in the central nervous system. It is therefore possible to conclude that oxycodone represents a valid alternative to morphine in the management of moderate to severe cancer pain, also as first-line treatment.

A systematic review of oxycodone in the management of cancer pain

BACKGROUND

Oxycodone is often used as an opioid analgesic for moderate to severe cancer-related pain, but its use varies across Europe. This systematic literature review forms the basis of guidelines for oxycodone use within the European Palliative Care Research Collaborative opioid guidelines project conducted on behalf of the European Association for Palliative Care.

OBJECTIVES

The objective of this study was to identify and assess the quality of evidence for the use of oxycodone for cancer pain in adults.

METHODS

The Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, MedLine, EMBASE and CINAHL were systematically searched in addition to hand searching of relevant journals. Studies were included if they reported a clinical outcome relevant to the use of oxycodone in adult patients with moderate to severe cancer pain. Any form and route of oxycodone was included except intrathecal. No direct comparator was required for inclusion and studies were excluded if patients had previously switched from another strong opioid because of intolerable adverse effects or poor efficacy. This is a narrative systematic review, using the GRADE approach to assess the quality of studies and to formulate guidelines.

RESULTS

Twenty-nine original studies were identified including a meta-analysis and 14 randomized controlled trials. The identified meta-analysis included three trials comparing oxycodone to morphine and one comparing oxycodone to hydromorphone. Four other randomized trials compared oxycodone with other opioids. The remaining randomized controlled trials compared different routes of administration or formulations of oxycodone. No additional studies that would have been suitable for addition to the meta-analysis were identified.

CONCLUSIONS

There is no evidence from the included trials of a significant difference in analgesia or adverse effects between oxycodone and morphine or hydromorphone. The evidence was graded as high quality on the basis of a well-conducted meta-analysis, with no limitations likely to affect the outcome, in addition to consistency in the results of the other studies. The research was conducted using participants relevant to cancer and palliative care populations. Oxycodone can be recommended as an alternative to morphine or hydromorphone for cancer-related pain.

Role of oxycodone and oxycodone/naloxone in cancer pain management

Oxycodone is a valued opioid analgesic, which may be administered either as the first strong opioid or when other strong opioids are ineffective. In case of insufficient analgesia and/or intense adverse effects such as sedation, hallucinations and nausea/vomiting a switch from another opioid to oxycodone might be beneficial. Oxycodone is administered to opioid-naive patients with severe pain and to patients who were unsuccessfully treated with weak opioids, namely tramadol, codeine and dihydrocodeine. Oxycodone effective analgesia may be attributed to its affinity to μ and possibly κ opioid receptors, rapid penetration through the blood-brain barrier and higher concentrations in brain than in plasma. Oxycodone displays high bioavailability after oral administration and may be better than morphine in patients with renal impairment due to the decreased production of active metabolites. Recently an oral controlled-release oxycodone formulation was introduced in Poland. Another new product that was launched recently is a combination of prolonged-release oxycodone with prolonged-release naloxone (oxycodone/naloxone tablets). The aim of this review is to outline the pharmacodynamic and pharmacokinetic properties, drug interactions, dosing rules, adverse effects, equianalgesic dose ratio with other opioids and clinical studies of oxycodone in patients with cancer pain. The potential role of oxycodone/naloxone in chronic pain management and its impact on the bowel function is also discussed.

Adequacy assessment of oxycodone/paracetamol (acetaminophen) in multimodal chronic pain : a prospective observational study

BACKGROUND

Multimodal pain is comprised of nociceptive/inflammatory and neuropathic components. Pharmacological pain therapies from different classes provide pain relief using different mechanistic actions; often a combination of such therapies provides more effective pain relief than monotherapy. To assess whether pain management is adequate requires a comprehensive pain scoring system.

OBJECTIVE

To evaluate the adequacy of a low-dose combination of oxycodone and paracetamol (acetaminophen) in patients with multimodal, chronic, non-malignant pain using the Pain Management Index (PMI).

METHODS

During this prospective, observational study, consecutive patients were classified according to the presence of prevalent osteoarticular pain (group A, n = 78) or prevalent neuropathic pain (group B, n = 72). Existing pain-relief medications were discontinued and both groups received oxycodone 5 mg and paracetamol 325 mg up to 8 hourly for a planned duration of >/= 6 weeks. Patients in group B who were receiving gabapentin continued this treatment up to a maximum daily dosage of 2400 mg during the observation period. Pain intensity was evaluated using a visual analogue scale (VAS from 0 to 10). Functional limitation for patients in group A was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The intensities of dynamic allodynia and hyperalgesia in patients in group B were evaluated by a VAS. Results from the WOMAC, dynamic allodynia, and hyperalgesia assessments were evaluated using the PMI.

RESULTS

In group A, 64.3% of patients showed improvements in pain symptoms after 15 days of treatment in the WOMAC categories of "pain preventing sleep" and "walks with aid". The PMI showed that the oxycodone/paracetamol therapy was adequate in patients with osteoarticular pain. In group B, 83.3% of patients reported improvement in the category of "pain preventing sleep", and all patients rated the remaining four categories ("spontaneous pain", "burning pain", "painful paresthesia", and "pinprick") as either stable or improved after 15 days of treatment. Using the PMI, hyperalgesia resolved with oxycodone/paracetamol therapy. 37.1% and 58.3% of patients did not complete the study in group A and B, respectively.

CONCLUSION

The PMI was an effective tool for assessment of pain management efficacy. Oxycodone/paracetamol improved pain symptoms in the majority of compliant patients. In patients with neuropathic pain, rescue therapy with oxycodone/paracetamol showed a lesser, but significant, improvement of pain symptoms.

A comparison of long- and short-acting opioids for the treatment of chronic noncancer pain: tailoring therapy to meet patient needs

Management of chronic noncancer pain (CNCP) requires a comprehensive assessment of the patient, the institution of a structured treatment regimen, an ongoing reassessment of the painful condition and its response to therapy, and a continual appraisal of the patient's adherence to treatment. For many patients with CNCP, the analgesic regimen will include opioids. Physicians should consider the available evidence of efficacy, the routes of administration, and the pharmacokinetics and pharmacodynamics of the various formulations as they relate to the temporal characteristics of the patient's pain. When making initial decisions, physicians should decide whether to prescribe a short-acting opioid (SAO) with a relatively quick onset of action and short duration of analgesic activity, a long-acting opioid (LAO) with a longer duration of analgesic action but a potentially longer onset of action, or both. Studies suggest that SAOs and LAOs are both effective for most types of CNCP. A review of published studies found no data to suggest that either SAOs or LAOs are generally more efficacious for treating any particular CNCP condition. The LAOs may provide more stable analgesia with less frequent dosing; however, opioid therapy should be tailored to the pain state and the individual patient, and SAOs may be appropriate for some patients with CNCP. MEDLINE and PubMed searches were conducted to locate relevant studies published from January 1975 to April 2008 using the following search terms: opioids, short-acting opioids, long-acting opioids, chronic pain, chronic pain AND opioids, and narcotics. English-only randomized controlled trials and nonrandomized studies were considered.

Oxycodone controlled-release as first-choice therapy for moderate-to-severe cancer pain in Italian patients: results of an open-label, multicentre, observational study

BACKGROUND AND OBJECTIVES

Cancer pain affects patients at all stages of the disease and there are clear guidelines for its management. Morphine is considered the first-choice strong opioid in the treatment of moderate-to-severe pain; however, numerous studies have shown that oxycodone controlled-release (CR) has a similar efficacy and safety profile. The purpose of this study was to evaluate the efficacy and tolerability of oxycodone CR as a first-line strong opioid for the treatment of moderate-to-severe pain in Italian cancer patients.

METHODS

This was a prospective, open-label, multicentre, observational trial carried out at 15 locations across Italy. Patients with a referral for cancer-related pain of > or =5 on a 10-point numerical rating scale were enrolled. Patients were treated with oral oxycodone CR and monitored for 21 days. Dosage was individualized for each patient and up-titrated until effective pain control was achieved. Pain, adverse events and quality-of-life scores were assessed throughout the study.

RESULTS

390 patients (174 females and 216 males) with a mean age of 66 +/- 11 years were evaluated. The average daily dose ranged from 22.84 on day 1 to 40 mg/day on day 21. Pain intensity (assessed on a 10-point numerical rating scale) decreased significantly within 1 day of treatment commencement (p = 0.00001) and continued to decrease throughout the study period (from a mean 7.22 at baseline to a mean 2.11 points on day 21). Adverse events were mild to moderate in intensity and consisted of common opioid-related events. Ten patients (2.6%) discontinued the study because of adverse events and four (1%) because of uncontrolled pain. All aspects of activities of daily life assessed were improved by study end.

CONCLUSIONS

Oxycodone CR is efficacious and well tolerated as a first-line strong opioid for the treatment of moderate-to-severe cancer-related pain in Italian patients.

Open experience with a new myorelaxant agent for low back pain

INTRODUCTION

Eperisone hydrochloride has been recently proposed as a muscle relaxant for the treatment of muscle contracture and chronic low back pain (LBP) as it is devoid of clinically relevant sedative effects on the central nervous system (CNS). We tested this hypothesis by performing a study of patients with LBP and muscle contracture who were treated with full-dose eperisone.

METHODS

Patients with moderate to severe, acute, or relapsing LBP received eperisone 100 mg three times daily for 10 consecutive days. Assessments included: spontaneous pain, pain on movement, resistance to passive movement, antalgic rigidity, and tolerability.

RESULTS

In total, 100 patients were enrolled into the study. The treatment achieved a consistent analgesic and muscle relaxant activity across all patients. Both spontaneous pain and pain on movement were significantly decreased, as was resistance encountered by the investigator to passive movements, antalgic rigidity, and muscle contracture. As a consequence, treatment with eperisone resulted in a lower rigidity of the lower back and an improved motility for patients. Only seven adverse reactions were reported, including light-headedness (1), occasional vertigo and/or loss of equilibrium (3), mild somnolence (2), and epigastric pain (1). In almost all cases, there was no need to interrupt the treatment and the adverse reaction resolved spontaneously.

CONCLUSIONS

Eperisone had an analgesic and muscle relaxant effect in patients with LBP. It should be noted that while it is common practice in rheumatology to combine a pain killer with a muscle relaxant in order to achieve a satisfactory result on both symptoms, the present results with eperisone were achieved with a single drug. With an improved tolerability profile compared with nonsteroidal anti-inflammatory drugs, and a lack of significant adverse effects on the CNS, eperisone hydrochloride represents a valuable alternative to traditional analgesics and muscle relaxants for the treatment of LBP.

Conversion from standard opioid therapy to once-daily oral extended-release hydromorphone in patients with chronic cancer pain

This open-label, multicenter study assessed the efficacy and tolerability of conversion to once-daily OROS hydromorphone from previous opioid agonist therapy in patients with chronic cancer pain. Patients were stabilized on their previous therapy before conversion at a 5:1 ratio of morphine sulfate to hydromorphone hydrochloride. The OROS hydromorphone dose was titrated over 3 - 21 days to achieve effective analgesia and was maintained for up to 14 days. Efficacy was assessed using the Brief Pain Inventory (BPI). Adverse events and vital signs were monitored. Dose stabilization was achieved in 119 of the 127 (94%) patients who received the study medication; in 77%, stabilization was achieved with no titration steps. Mean BPI pain intensity ratings and BPI pain interference scores decreased significantly after OROS hydromorphone treatment compared with pretreatment values. Mean pain-relief level remained stable after conversion and throughout treatment with OROS hydromorphone. Adverse events were as expected for cancer patients receiving opioid agonists. There were no clinically significant changes in vital signs.

The efficacy of oxycodone for management of acute pain episodes in chronic neck pain patients

OBJECTIVE

Most treatments of acute pain associated with non-malignant chronic pains are not satisfactory. The aim of this study is to evaluate the efficacy and side effects of oxycondone controlled release (Oxy-CR) in managing chronic neck pain with acute pain episodes.

DESIGN

Randomised, double-blind, stand controlled study. A total of 116 patients were evenly divided into an oxycodone group (Oxy-CR, 5-10 mg and q12 h/day) and a placebo group (placebo, q12 h/day). Patients were assessed for the frequency of pain flares, visual analgesia score (VAS), quality of life (QOL), quality of sleep (QOS) and adverse effects before the treatment and on days 1, 3, 7, 14, 21 and 28 after the treatment. Withdrawal symptoms were monitored during the study, also on the completion of the entire study. The SF-36 was administered at the beginning and the end of the study for each patient.

RESULTS

Compared with the baselines of Oxy-CR and the placebo groups, the frequency of pain episodes and VAS were decreased significantly starting on day 3 of administration of Oxy-CR (p<0.05). Improvements in QOL and QOS were significant on day 3 after treatment with Oxy-CR (p<0.05). The patients who were treated with Oxy-CR reported significantly higher side effects than the patients in the placebo group (p<0.05). However, these side effects started to diminish after day 7 of the treatment. Withdrawal symptoms did not emerge in this study. Most domains of SF-36 were improved in the treated patients at the end of study (p<0.05).

CONCLUSION

Oxycondone controlled release could be an important optional drug for the management of refractory and frequent acute episodes of chronic neck pain in patients who failed to respond to non-opioid conservative treatment.

Oxycodone: a review of its use in the management of pain

BACKGROUND

Oxycodone is a strong opioid that acts at mu- and kappa-opioid receptors. It has pharmacological actions similar to strong opioids, but with a specific pharmacologic profile and greater analgesic potency to morphine. The efficacy of oxycodone in managing neuropathic and somatic pain, both of malignant and non-malignant origin, has been established in a wide range of settings.

SCOPE

This review aims to provide a comprehensive evaluation of oxycodone and its role within clinical settings in order to provide an evidence-based perspective on its use in the clinic. Literature searches using Medline, EMBASE and Cochrane Databases were used to compile data for review. The review provides information on the pharmacokinetics and pharmacodynamics of oxycodone and also profiles established clinical data in neuropathic and somatic pain as well as emerging data to support the use of oxycodone in visceral pain, which may be due to its interaction with kappa-opioid receptors. Oxycodone is available in a range of formulations for oral, intraspinal and parenteral administration.

FINDINGS

The prolonged-release form of oxycodone offers a fast onset of analgesia, controlling pain for 12 hours and providing clinically meaningful relief of moderate to severe pain and improving quality of life across a broad spectrum of pain types.

CONCLUSIONS

Oxycodone provides significant pain relief. It has relevant points of difference from other opioids and as such may be a suitable alternative to morphine.

Once-daily OROS hydromorphone for the management of chronic nonmalignant pain: a dose-conversion and titration study

BACKGROUND

The use of opioid analgesics for patients with chronic nonmalignant pain is becoming more widely accepted, and long-acting formulations are an important treatment option.

AIM

To assess conversion to extended-release OROS hydromorphone from previous stable opioid agonist therapy in patients with chronic nonmalignant pain of moderate-to-severe intensity.

METHODS

In this open-label multicentre trial, patients were stabilised on their previous opioid therapy before being switched to OROS hydromorphone at a ratio of 5 : 1 (morphine sulphate equivalent to hydromorphone hydrochloride). The OROS hydromorphone dose was titrated over 3-16 days to achieve effective analgesia, and maintenance treatment continued for 14 days.

RESULTS

Study medication was received by 336 patients; 66% completed all study phases. Stabilisation of OROS hydromorphone was achieved by 94.6% of patients, the majority in two or fewer titration steps (mean time, 4.2 days). Mean pain intensity scores, as determined by the Brief Pain Inventory, decreased during OROS hydromorphone treatment (p <or= 0.001). The percentage of patients rating their pain relief as 'good' or 'complete' increased, and the use of rescue analgesics for breakthrough pain decreased. The interference of pain with everyday activities (e.g. walking or work), and the effects on mood and enjoyment of life, also improved during the study (all p < 0.001). OROS hydromorphone was well tolerated, and adverse events were those expected for opioid agonist therapy.

CONCLUSION

Patients with chronic nonmalignant pain who had been receiving opioid therapy easily underwent conversion to OROS hydromorphone, with no loss of efficacy or increase in adverse events.

Oxycodone: a pharmacological and clinical review

Oxycodone is a semi-synthetic opioid with an agonist activity on mu, kappa and delta receptors. Equivalence with regard to morphine is 1:2. Its effect commences one hour after administration and lasts for 12 h in the controlled-release formulation. Plasma halflife is 3-5 h (half that of morphine) and stable plasma levels are reached within 24 h (2-7 days for morphine). Oral bioavailability ranges from 60 to 87%, and plasma protein binding is 45%. Most of the drug is metabolised in the liver, while the rest is excreted by the kidney along with its metabolites. The two main metabolites are oxymorphone--which is also a very potent analgesic--and noroxycodone, a weak analgesic. Oxycodone metabolism is more predictable than that of morphine, and therefore titration is easier. Oxycodone has the same mechanism of action as other opioids: binding to a receptor, inhibition of adenylyl-cyclase and hyperpolarisation of neurons, and decreased excitability. These mechanisms also play a part in the onset of dependence and tolerance. The clinical efficacy of oxycodone is similar to that of morphine, with a ratio of 1/1.5-2 for the treatment of cancer pain. Long-term administration may be associated with less toxicity in comparison with morphine. In the future, both opioids could be used simultaneously at low doses to reduce toxicity. It does not appear that there are any differences between immediate and slow-release oxycodone, except their half-life is 3-4 h, and 12 h, respectively. In Spain, controlled-release oxycodone (OxyContin) is marketed as 10-, 20-, 40- or 80-mg tablets for b.i.d. administration. Tablets must be taken whole and must not be broken, chewed or crushed. There is no food interference. The initial dose is 10 mg b.i.d. for new treatments and no dose reduction is needed in the elderly or in cases of moderate hepatic or renal failure. Immediate-release oxycodone (OxyNorm) is also available in capsules and oral solution. Side effects are those common to opioids: mainly nausea, constipation and drowsiness. Vomiting, pruritus and dizziness are less common. The intensity of these side effects tends to decrease over the course of time. Oxycodone causes somewhat less nausea, hallucinations and pruritus than morphine.

Revisión sistemática: ¿son eficaces los opiáceos mayores en el tratamiento del dolor osteomuscular?

BACKGROUND AND OBJECTIVE

To evaluate the efficacy of major opioids in the treatment of musculoskeletal pain.

MATERIAL AND METHOD

Systematic review. A sensitive search strategy was undertaken in MEDLINE and EMBASE up to April 2005. The Cochrane Library and the abstracts of the 2004-2005 meetings of the American College of Rheumatology were also hand searched. All randomized controlled trials of major opiods in patients with musculoskeletal pain were selected. An analytical review was performed and evidence tables produced. A meta-analysis was run when appropriate.

RESULTS

We obtained 427 references from the search, (27 duplicated from MEDLINE and EMBASE, 2 from the Cochrane Library, and 5 abstracts), of which 68 articles plus one meeting abstract were selected for detailed analysis. Of these, 23 finally met the inclusion criteria. Combined analysis of oral major opioids versus placebo showed significant improvement in pain relief in patients with osteoarthritis.

CONCLUSIONS

Specific major opioids can reduce pain in patients with chronic musculoskeletal disorders. The clinical trials report positive effects on pain and the meta-analysis confirms these effects.

Economic evaluation of Durogesic in moderate to severe, nonmalignant, chronic pain in Germany

We carried out a cost-effectiveness evaluation of transdermal fentanyl compared to three other widely used opioids: transdermal buprenorphine, sustained-release morphine, and controlled-release oxycodone from a third-party-payers perspective. A decision analytic model with data from a structured database search and from panel data and assumptions was used to derive both cost and utility results. Probabilistic sensitivity analysis was performed to ensure the findings. Transdermal fentanyl patients gain more quality adjusted life-days or quality-adjusted life-years per euro. The incremental cost per quality-adjusted life-year is 1,625.65 euro for transdermal fentanyl compared to sustained-release morphine and 1,003.03 euro compared to CO, and it is cost-saving compared to transdermal buprenorphine (-203.38 euro per patient). Transdermal fentanyl is thus cost-effective compared to both sustained-release morphine and CO and dominant compared to transdermal buprenorphine in the treatment of adults with nonmalignant moderate to severe chronic pain.

Optimizing use of opiates in the management of cancer pain

Cancer pain is often suboptimally managed. The underestimation and undertreatment continues to be a problem despite the availability of consensus-based guidelines. Most patients with cancer develop pain. The prevalence and severity of pain among cancer patients varies according to primary and metastatic sites and stage of disease. Opioid therapy is the cornerstone of management of severe chronic pain in the field of cancer patients and in general in palliative care medicine. Since this class of drugs is the cornerstone of the treatment, optimizing its use may be useful in clinical practice. For this purpose we focused on 4 distinct issues: 1) How to implement the use the opioids in cancer patients; 2) How to optimise the use of morphine in cancer patients; 3) The management of side effects and opioid switching; 4) What is the role of other potent opioids. A holistic approach including an appropriate use of opioids may improve pain control in most cancer patients, particularly for those with advanced disease.

The DIRE score: predicting outcomes of opioid prescribing for chronic pain

The objective of this retrospective study was to test the validity and reliability of a scoring tool (the DIRE Score), for use by clinicians, that predicts which chronic noncancer pain patients will have effective analgesia and be compliant with long-term opioid maintenance treatment. DIRE scores were assigned to 61 cases from the pain center's databases. These cases were abstracted into vignettes that were reviewed and scored by 6 physicians. Repeat scoring was carried out on a subset of 30 vignettes after 2 weeks. The main outcome measures were: global impression of compliance and efficacy as indicated in the medical record and by interview with the patient's treating clinician; and final disposition, ie, whether or not opioids were continued or discontinued at the time of last clinical documentation. Internal consistency of the factors making up the DIRE Score was high (Cronbach's alpha = .80). Sensitivity and specificity of the DIRE Score for predicting patient compliance were 94% and 87%, respectively. For efficacy, sensitivity and specificity were 81% and 76%. For disposition, the sensitivity and specificity were 86% and 73%. Intraclass correlation was 0.94 for interrater reliability and 0.95 for intrarater reliability.

PERSPECTIVE

Public controversy about the use of long-term opioids for chronic pain fuels physician ambivalence about the prescribing process. In this initial retrospective study, validity and reliability of the DIRE Score are demonstrated. The score correlated well with measures of patient compliance and efficacy of long-term opioid therapy.

Pain management

This article provides information regarding treatments for the management of moderate to severe pain in patients who are at the end of life. Discussion focuses on the use of strong opioids and adjuvant analgesics. Special attention also is given to the most frequently used forms of interventional pain management. Although pain in terminally ill patients is not always related to cancer, many of the studies cited in this article were performed in cancer patients, a model that informs much of what is presented.