The dose-response relationship of controlled-release codeine (Codeine Contin) in chronic cancer pain

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.

A Review of Analytical Methods for Codeine Determination

Codeine is derived from morphine, an opioid analgesic, and has weaker analgesic and sedative effects than the parent molecule. This weak opioid is commonly used in combination with other drugs for over-the-counter cough relief medication. Due to the psychoactive properties of opioid drugs, the easily obtained codeine often becomes subject to misuse. Codeine misuse has emerged as a concerning public health issue due to its associated adverse effects such as headache, nausea, vomiting, and hemorrhage. Thus, it is very important to develop reliable analytical techniques to detect codeine for both quality control of pharmaceutical formulations and identifying drug misuse in the community. This review aims to provide critical outlooks on analytical methods applicable to the determination of codeine.

Systematic review and meta-analysis on non-opioid analgesics in palliative medicine

Non-opioid analgesics are widely used for pain relief in palliative medicine. However, there is a lack of evidence-based recommendations addressing the efficacy, tolerability, and safety of non-opioids in this field. A comprehensive systematic review and meta-analysis on current evidence can provide a basis for sound recommendations in clinical practice. A database search for controlled trials on the use of non-opioids in adult palliative patients was performed in Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, and EMBASE from inception to 18 February 2018. Endpoints were pain intensity, opioid-sparing effects, safety, and quality of life. Studies with similar patients, interventions, and outcomes were included in the meta-analyses. Our systematic search was able to only identify studies dealing with cancer pain. Of 5991 retrieved studies, 43 could be included (n = 2925 patients). There was no convincing evidence for satisfactory pain relief by acetaminophen alone or in combination with strong opioids. We found substantial evidence of moderate quality for a satisfactory pain relief in cancer by non-steroidal anti-inflammatory drugs (NSAIDs), flupirtine, and dipyrone compared with placebo or other analgesics. There was no evidence for a superiority of one specific non-opioid. There was moderate quality of evidence for a similar pain reduction by NSAIDs in the usual dosage range compared with up to 15 mg of morphine or opioids of equianalgesic potency. The combination of NSAID and step III opioids showed a beneficial effect, without a decreased tolerability. There is scarce evidence concerning the combination of NSAIDs with weak opioids. There are no randomized-controlled studies on the use of non-opioids in a wide range of end-stage diseases except for cancer. Non-steroidal anti-inflammatory drugs, flupirtine, and dipyrone can be recommended for the treatment of cancer pain either alone or in combination with strong opioids. The use of acetaminophen in the palliative setting cannot be recommended. Studies are not available for long-term use. There is a lack of evidence regarding pain treatment by non-opioids in specific cancer entities.

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.

Oral nonsteroidal anti-inflammatory drugs (NSAIDs) for cancer pain in adults

BACKGROUND

Pain is a common symptom with cancer, and 30% to 50% of all people with cancer will experience moderate to severe pain that can have a major negative impact on their quality of life. Non-opioid drugs are commonly used to treat cancer pain, and are recommended for this purpose in the World Health Organization (WHO) cancer pain treatment ladder, either alone or in combination with opioids.A previous Cochrane review that examined the evidence for nonsteroidal anti-inflammatory drugs (NSAIDs) or paracetamol, alone or combined with opioids, for cancer pain was withdrawn in 2015 because it was out of date; the date of the last search was 2005. This review, and another on paracetamol, updates the evidence.

OBJECTIVES

To assess the efficacy of oral NSAIDs for cancer pain in adults, and the adverse events reported during their use in clinical trials.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase from inception to April 2017, together with reference lists of retrieved papers and reviews, and two online study registries.

SELECTION CRITERIA

We included randomised, double-blind, single-blind, or open-label studies of five days' duration or longer, comparing any oral NSAID alone with placebo or another NSAID, or a combination of NSAID plus opioid with the same dose of the opioid alone, for cancer pain of any pain intensity. The minimum study size was 25 participants per treatment arm at the initial randomisation.

DATA COLLECTION AND ANALYSIS

Two review authors independently searched for studies, extracted efficacy and adverse event data, and examined issues of study quality and potential bias. We did not carry out any pooled analyses. We assessed the quality of the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

Eleven studies satisfied inclusion criteria, lasting one week or longer; 949 participants with mostly moderate or severe pain were randomised initially, but fewer completed treatment or had results of treatment. Eight studies were double-blind, two single-blind, and one open-label. None had a placebo only control; eight compared different NSAIDs, three an NSAID with opioid or opioid combination, and one both. None compared an NSAID plus opioid with the same dose of opioid alone. Most studies were at high risk of bias for blinding, incomplete outcome data, or small size; none was unequivocally at low risk of bias.It was not possible to compare NSAIDs as a group with another treatment, or one NSAID with another NSAID. Results for all NSAIDs are reported as a randomised cohort. We judged results for all outcomes as very low-quality evidence.None of the studies reported our primary outcomes of participants with pain reduction of at least 50%, and at least 30%, from baseline; participants with Patient Global Impression of Change (PGIC) of much improved or very much improved (or equivalent wording). With NSAID, initially moderate or severe pain was reduced to no worse than mild pain after one or two weeks in four studies (415 participants in total), with a range of estimates between 26% and 51% in individual studies.Adverse event and withdrawal reporting was inconsistent. Two serious adverse events were reported with NSAIDs, and 22 deaths, but these were not clearly related to any pain treatment. Common adverse events were thirst/dry mouth (15%), loss of appetite (14%), somnolence (11%), and dyspepsia (11%). Withdrawals were common, mostly because of lack of efficacy (24%) or adverse events (5%).

AUTHORS' CONCLUSIONS

There is no high-quality evidence to support or refute the use of NSAIDs alone or in combination with opioids for the three steps of the three-step WHO cancer pain ladder. There is very low-quality evidence that some people with moderate or severe cancer pain can obtain substantial levels of benefit within one or two weeks.

WITHDRAWN: NSAIDS or paracetamol, alone or combined with opioids, for cancer pain

This review is out of date, although it is correct at the date of publication. The review may be misleading as new studies could alter the original conclusions. All previous versions of the review can be found in the ‘Other versions’ tab. A new author team intends to develop four new reviews on this topic, which will serve to update and supersede this review. The new reviews will cover paracetamol, paracetamol plus opioids, NSAIDs, and NSAIDs plus opioids, for cancer pain. For more information, contact the PaPaS Review Group.

The editorial group responsible for this previously published document have withdrawn it from publication.

Codeine, alone and with paracetamol (acetaminophen), for cancer pain

BACKGROUND

Pain is very common in patients with cancer. Opioid analgesics, including codeine, play a significant role in major guidelines on the management of cancer pain, particularly for mild to moderate pain. Codeine is widely available and inexpensive, which may make it a good choice, especially in low-resource settings. Its use is controversial, in part because codeine is not effective in a minority of patients who cannot convert it to its active metabolite (morphine), and also because of concerns about potential abuse, and safety in children.

OBJECTIVES

To determine the efficacy and safety of codeine used alone or in combination with paracetamol for relieving cancer pain.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library 2014, Issue 2), MEDLINE and EMBASE from inception to 5 March 2014, supplemented by searches of clinical trial registries and screening of the reference lists of the identified studies and reviews in the field.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials using single or multiple doses of codeine, with or without paracetamol, for the treatment of cancer pain. Trials could have either parallel or cross-over design, with at least 10 participants per treatment group. Studies in children or adults reporting on any type, grade, and stage of cancer were eligible. We accepted any formulation, dosage regimen, and route of administration of codeine, and both placebo and active controls.

DATA COLLECTION AND ANALYSIS

Two review authors independently read the titles and abstracts of all studies identified by the searches and excluded those that clearly did not meet the inclusion criteria. For the remaining studies, two authors read the full manuscripts and assessed them for inclusion. We resolved discrepancies between review authors by discussion. Included studies were described qualitatively, since no meta-analysis was possible because of the small amount of data identified, and clinical and methodological between-study heterogeneity.

MAIN RESULTS

We included 15 studies including 721 participants with cancer pain due to diverse types of malignancy. All studies were performed on adults; there were no studies on children. The included studies were of adequate methodological quality, but all except for one were judged to be at a high risk of bias because of small study size, and six because of methods used to deal with missing data or high withdrawal rates. Three studies used a parallel group design; the remainder were cross-over trials in which there was an adequate washout period, but only one reported results for treatment periods separately.Twelve studies used codeine as a single agent and three combined it with paracetamol. Ten studies included a placebo arm, and 14 included one or more of 16 different active drug comparators or compared different routes of administration. Most studies investigated the effect of a single dose of medication, while five used treatment periods of one, seven or 21 days. Most studies used codeine at doses of 30 mg to 120 mg.There were insufficient data for any pooled analysis. Only two studies reported our preferred responder outcome of 'participants with at least 50% reduction in pain' and two reported 'participants with no worse than mild pain'. Eleven studies reported treatment group mean measures of pain intensity or pain relief; overall for these outcome measures, codeine or codeine plus paracetamol was numerically superior to placebo and equivalent to the active comparators.Adverse event reporting was poor: only two studies reported the number of participants with any adverse event specified by treatment group and only one reported the number of participants with any serious adverse event. In multiple-dose studies nausea, vomiting and constipation were common, with somnolence and dizziness frequent in the 21-day study. Withdrawal from the studies, where reported, was less than 10% except in two studies. There were three deaths, in all cases due to the underlying cancer.

AUTHORS' CONCLUSIONS

We identified only a small amount of data in studies that were both randomised and double-blind. Studies were small, of short duration, and most had significant shortcomings in reporting. The available evidence indicates that codeine is more effective against cancer pain than placebo, but with increased risk of nausea, vomiting, and constipation. Uncertainty remains as to the magnitude and time-course of the analgesic effect and the safety and tolerability in longer-term use. There were no data for children.

The Effects of Intraarticular Opioids in pain relief after Arthroscopic Menisectomy: A Randomized Clinical Trial Study

Objective: Knee arthroscopy is a painful procedure which if untreated will cause intensive and prolonged pain that may prevent rehabilitation of patients. This study was designed to compare the analgesic effects of different opioids in the early post operative period in comparison to control group.

Methodology: One hundred forty patients were prospectively assigned to four groups randomly. After arthroscopic menisectomy all patients received an intraarticular injection containing 9.5 ml bupivacaine 0.5% with 1:200000 epinephrine in a 10 ml syringe. The remainder of syringe was filled with one of the study solutions. Group I: 5mg methadone, group II: 5mg morphine, group III: 5 ml normal saline, group IV: 50 mg meperidine. At three stages in the ealy post operative period the need for analgesics was recorded. A statistical comparison was done afterwards.

Results: In morphine group (group II), the analgesic usage in hospitalized and outpatients compared with other groups was significantly low(P<0.05).

Conclusion: Morphine in comparison to meperidine or methadone is more beneficial in reducing pain or analgesic need when is added to bupivacain injection following arthroscopic menisectomy.

Recent updates on codeine

Alleviation of pain is a major objective in medicine to increase the quality of life. Analgesics are agents that relieve pain by elevating the pain threshold without disturbing consciousness or altering other sensory modalities. Opium is an isoquinoline alkaloid obtained from poppy plant Papaver somniferum (Papaveraceae). Codeine is an alkaloid prepared from opium or morphine by methylation. Codeine is used as a central analgesic, sedative, hypontic, antinonciceptive, antiperistaltic, and is also recommended in tuberculosis and insomnia due to incessant coughing. The literature information relate mostly to the determination of codeine active components using Gas chromatography (GC), Capillary electrophoresis, Thin layer chromatography, High-performance thin layer chromatography, UV–Vis Spectrophotometry, High-performance liquid chromatography and GC in combination with Mass spectroscopy. This contribution provides a comprehensive review of its analytical and pharmacologic profile of codeine.

The role of paracetamol and nonsteroidal anti-inflammatory drugs in addition to WHO Step III opioids in the control of pain in advanced cancer. A systematic review of the literature

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) and paracetamol are used widely in the management of mild to moderate cancer pain and are frequently combined with opioids in the treatment of moderate to severe pain.

AIM

To perform a systematic literature review of the evidence of the efficacy and toxicity of NSAIDs or paracetamol added to WHO Step III opioid treatment for cancer pain.

DESIGN AND DATA SOURCES

A systematic literature review of MedLine, EMBASE and Cochrane Central register of controlled trials database was carried out using both text words and MeSH/EMTREE terms.

RESULTS

Seven eligible papers were retrieved from the new search and five from the Cochrane review. Five of seven studies showed an additive effect of NSAIDs when combined with opioids either by improving analgesia (three studies) or by reducing the opioid dose (two studies). Paracetamol was only marginally effective in one of five trials. The study designs were not adequate to assess differences in side effects between the opioids alone and opioids in combination with NSAIDs or paracetamol.

CONCLUSIONS

The evidence from the available clinical trials is of limited amount and quality, but it weakly supports the proposal that the addition of an NSAIDs to WHO Step III opioids can improve analgesia or reduce opioid dose requirement. There is insufficient evidence to support the use of paracetamol in combination with Step III opioids. Data on the toxicity of NSAIDs in this indication are insufficient owing to the small number of patients and the short duration of treatment reported in the studies.

Use of opioid analgesics in the treatment of cancer pain: evidence-based recommendations from the EAPC

Here we provide the updated version of the guidelines of the European Association for Palliative Care (EAPC) on the use of opioids for the treatment of cancer pain. The update was undertaken by the European Palliative Care Research Collaborative. Previous EAPC guidelines were reviewed and compared with other currently available guidelines, and consensus recommendations were created by formal international expert panel. The content of the guidelines was defined according to several topics, each of which was assigned to collaborators who developed systematic literature reviews with a common methodology. The recommendations were developed by a writing committee that combined the evidence derived from the systematic reviews with the panellists' evaluations in a co-authored process, and were endorsed by the EAPC Board of Directors. The guidelines are presented as a list of 16 evidence-based recommendations developed according to the Grading of Recommendations Assessment, Development and Evaluation system.

NSAIDS or paracetamol, alone or combined with opioids, for cancer pain

BACKGROUND

NSAIDs are widely applied to treat cancer pain and are frequently combined with opioids in combination preparations for this purpose. However, it is unclear which agent is most clinically efficacious for relieving cancer-related pain, or even what may be the additional benefit of combining an NSAID with an opioid in this setting.

OBJECTIVES

To assess the effects of NSAIDs, alone or combined with opioids, for the treatment of cancer pain.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (Issue 2, 2002), MEDLINE (January 1966 to March 2003), EMBASE (January 1980 to December 2001), LILACS (January 1984 to December 2001) and reference list of articles.

SELECTION CRITERIA

Randomized controlled trials and controlled clinical trials that compared NSAID versus placebo; NSAID versus NSAID; NSAID versus NSAID plus opioid; opioid versus opioid plus NSAID; or NSAID versus opioid.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Adverse event information was collected from trials. Where there was disagreement between reviewers, the opinion of an additional reviewer was sought to resolve the issue.

MAIN RESULTS

Forty-two trials involving 3084 patients were included. Clinical heterogeneity of study methods and outcomes precluded meta-analyses and only supported a qualitative systematic review. Seven of eight papers that compared NSAID with placebo demonstrated superior efficacy of NSAID with no difference in side effects. Thirteen papers compared one NSAID with another; four reported increased efficacy of one NSAID over another. Four different studies found that one NSAID had fewer side effects than one or more others. Twenty-three studies compared NSAIDs and opioids in combination or alone with NSAID/opioid combinations. Thirteen out of 14 studies found no difference, or low clinical difference, when combining an NSAID plus an opioid versus either drug alone. Comparisons between various NSAID/opioid combinations were inconclusive. Nine studies assessed the association between dose and efficacy and safety. Four papers demonstrated increased efficacy with increased dose, but no dose-dependent increase in side effects within the dose ranges studied. Study duration ranged from single dose studies performed over six hours to crossover studies lasting six weeks; however the majority of studies were of less than seven days duration.

AUTHORS' CONCLUSIONS

Based upon limited data, NSAIDs appear to be more effective than placebo for cancer pain; clear evidence to support superior safety or efficacy of one NSAID over another is lacking; and trials of combinations of an NSAID with an opioid have disclosed either no difference (4 out of 14 papers), a statistically insignificant trend towards superiority (1 out of 14 papers), or at most a slight but statistically significant advantage (9 out of 14 papers), compared with either single entity. The short duration of studies undermines generalization of their findings on efficacy and safety of NSAIDs for cancer pain.

Nonsteroidal Anti-Inflammatory Drugs, Alone or Combined With Opioids, for Cancer Pain

Purpose

To assess the safety and efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs), alone or combined with opioids, for the treatment of cancer pain.

Patients and Methods

Forty-two trials involving 3,084 patients met inclusion criteria: eight compared NSAID with placebo; 13 compared one NSAID with another; 23 compared NSAID with opioid, NSAID or opioid versus NSAID plus opioid combinations, or NSAID plus opioid combinations versus NSAID plus opioid combinations; and nine studies assessed the effect of increasing NSAID dose.

Results

Sixteen studies lasted 1 week or longer and 11 evaluated a single dose. Seven of eight trials demonstrated superior efficacy of single doses of NSAID compared with placebo. Only four of 13 studies reported increased efficacy of one NSAID compared with another; four other studies found that one NSAID had fewer side effects than one or more others. Thirteen of 14 studies found no difference, or minimal clinical difference, when comparing an NSAID plus opioid combination versus either drug alone. Comparisons between various NSAID plus opioid combinations were inconclusive. Four studies demonstrated increased efficacy with increased NSAID dose, without dose-dependent increases in side effects.

Conclusion

Heterogeneity of study methods and outcomes precluded meta-analyses. Short duration of studies undermines generalization of findings on efficacy and safety. On the basis of limited data, NSAIDs appear to be more effective than placebo for cancer pain; clear evidence to support superior safety or efficacy of one NSAID compared with another is lacking; and trials of combinations of an NSAID with an opioid have disclosed either no significant difference, or at most a slight but statistically significant advantage, compared with either single entity.

In vivo pain relief effectiveness of an analgesic-anesthetic carrying biodegradable controlled release rod systems

Pain is the most common and feared symptom for patients, especially those with cancer. Treatment of chronic pain with conventional ways of medication usually fails with increasing severity of the pain. New approaches enabling the prolonged provision of pain relievers are required. We designed a controlled release system of pain relievers, mainly for opioids (morphine, M, codeine, C, and hydromorphone, HM), and a local anesthetic (bupivacaine, BP) in the form of poly(L-lactide-co-glycolide) (PLGA) rods. The efficacy of these rods implanted alone or in combination in relieving chronic pain in rats caused by the ligation of the sciatic nerve of their right hind limbs was studied. The two most common tests for measuring analgesia, i.e. tail-flick tests, that show analgesia at sites other than the site of injury, were used to study the degree of systemic distribution of the drugs and paw-withdrawal tests were used to study the analgesia at the site of injury. Alleviation of this chronic and severe neuropathic pain could be obtained for about 3-4 days when rods for two drugs, 'dual drug' (analgesic-anesthetic), were used. This duration is decreased by half (2 days) with the single-drug rods. Also the dual-drug rods, though at half the dose of each single drug application, enhanced the degree of analgesia of the first day. These in vivo results are also consistent with the previous in vitro results as in the case with codeine which had a higher first-day analgesia than morphine, despite a lower potency due to the faster in vitro release rate. Similarly, slower release of hydromorphone from PLGA (85:15) rods resulted in less systemic analgesia than the more rapidly eroding PLGA (50:50) rods of the same drug.

Antihyperalgesic effect of simultaneously released hydromorphone and bupivacaine from polymer fibers in the rat chronic constriction injury model

We aimed to evaluate the antihyperalgesic efficacy of a combination of hydromorphone (HM) and bupivacaine (BP) delivered via controlled release from a biodegradable cylindrical rod. In vivo studies were performed using a rat model of thermal hyperalgesia induced by chronic constriction injury (CCI) of the sciatic nerve with loose ligatures. Poly(lactic-co-glycolic acid) (PLGA) rods (10 mm length, 1 mm diameter) loaded with HM (5 mg per rod), BP (5 mg per rod) or no drug (placebo) were implanted subcutaneously, in single or dual pairs, adjacent to the constriction injury, immediately after nerve ligation. We evaluated the efficacy of two dose levels for each drug, alone or in combination, in attenuating thermal hyperesthesia over a period of 12 days according to a prevention protocol. Plasma levels of drugs released from the rods and also released in an in vitro simulation were evaluated. In vitro studies demonstrated that drug release is maintained for at least 10 days. HM (5 mg) alone and BP (5 mg) alone did not attenuate hyperalgesia. Their combination provided a significant increase in the paw withdrawal latency as compared to single agents or placebo. When the dose in each group was doubled, implanting four rods, significant attenuation of hyperalgesia was observed. Analyses of rods retrieved after termination of experiments (after 12 days) revealed 30% residual HM and 70% residual BP content. Prolonged delivery of HM and BP alone or in combination via locally applied PLGA rods may offer a feasible alternative to provide long-lasting analgesia.

Randomized evaluation of controlled-release codeine and placebo in chronic cancer pain

Codeine is widely used in combination with acetaminophen and aspirin for the management of mild to moderate pain. However, there are few controlled clinical trials of single-entity codeine in chronic cancer pain. The purpose of this study was to evaluate the clinical efficacy and safety of controlled-release codeine given every 12 hr in patients with cancer pain. Thirty-five patients with chronic cancer pain were randomized in a double-blind crossover study to controlled-release (CR) codeine or placebo, for 7 days each. Pain intensity was assessed at 0800 hr and 2000 hr using a visual analogue scale (VAS) and a five-point categorical scale, and the use of "rescue" acetaminophen-plus-codeine (300 mg/30 mg every 4 hr as needed) was recorded. Thirty patients completed the study (17 male, 13 female; mean age, 64.4 +/- 9.8 years) with a mean daily CR codeine dose of 277 +/- 77 mg (range, 200-400 mg). CR codeine treatment resulted in significantly lower overall VAS pain intensity scores (22 +/- 18 mm versus 36 +/- 20 mm, P = 0.0001), categorical pain intensity scores (1.2 +/- 0.8 versus 1.8 +/- 0.8, P = 0.0001), and pain scores when assessed by day of treatment and by time of day. Daily "rescue" analgesic consumption was significantly lower on CR codeine, compared to placebo treatment (2.2 +/- 2.3 versus 4.6 +/- 2.8 tablets per day, P = 0.0001). Both patients and investigators preferred CR codeine to placebo (80% versus 3%, P = 0.0014 and 73% versus 7%, P = 0.0160, respectively). These data indicate that CR codeine, given every 12 hr results in significant reductions in pain intensity and the use of "rescue" acetaminophen-plus-codeine in patients with cancer pain. CR codeine provides the benefits of a flexible single entity codeine formulation and the convenience of 12-hr duration of action, which allows patients uninterrupted sleep and improved compliance.

Efficacy of controlled-release codeine in chronic non-malignant pain: a randomized, placebo-controlled clinical trial

Treatment decisions for the use of opioid analgesics in chronic non-malignant pain are based primarily on survey data, as evidence from well-controlled clinical trials has been lacking. Forty-six patients with chronic non-malignant pain were enrolled in a randomized, double-blind, placebo-controlled evaluation of controlled-release (CR) codeine. Following a 3-7-day diary familiarization period, patients were randomly assigned to 7 days of treatment each with CR codeine q12h or placebo. The CR codeine dose was determined from the consumption of acetaminophen+codeine in the 7 days preceding the study. During both phases, breakthrough pain was treated with acetaminophen+codeine every 4 h as required. Pain intensity was assessed at 08:00 h and 20:00 h using a visual analogue scale (VAS) and a 5-point categorical scale, and rescue analgesic consumption was recorded at the time of use. Thirty patients (17 female, 13 male; mean age: 55.1 +/- 13.4 years) completed the study and were treated with a mean daily CR codeine dose of 273 +/- 78 mg (range: 200-400 mg). CR codeine treatment resulted in significantly lower overall VAS pain intensity scores (35 +/- 18 vs. 49 +/- 16, P = 0.0001), categorical pain intensity scores (1.7 +/- 0.6 vs. 2.2 +/- 0.6, P = 0.0001), and in pain scores by day of treatment and by time of day. Daily rescue analgesic consumption was significantly lower on CR codeine, relative to placebo treatment (3.6 +/- 3.5 vs. 6.1 +/- 3.2 tablets/day, P = 0.0001). There was also a significant reduction in the Pain Disability Index (PDI) on CR codeine, compared to placebo (25.0 +/- 7.7 vs. 35.1 +/- 8.2, P = 0.0001). Patients' and investigators' blinded treatment preference was significantly in favor of CR codeine, relative to placebo (73% vs. 10%, P = 0.0160 and 80% vs. 7%, P = 0.0014, respectively). The incidence of nausea was significantly higher on CR codeine than on placebo (32.6% vs. 11.9%, P = 0.013). Ninety-three percent of patients completing the study requested long-term, open-label treatment with CR codeine. Pain intensity scores at the completion of 19 weeks of long-term evaluation were comparable to those during the double-blind CR codeine treatment. We conclude that treatment with CR codeine results in reduced pain and pain-related disability in patients with chronic non-malignant pain.