Efficacy and safety of transdermal buprenorphine: a randomized, placebo-controlled trial in 289 patients with severe cancer pain

A Phase II Study About Efficacy and Safety of the Continuous IntraVenous Infusion of Ketamine as Adjuvant to Opioids in Terminally Ill Cancer Patients With Refractory Cancer Pain (CIVIK Trial)

BACKGROUND

Ketamine has been used to control refractory cancer pain as an adjuvant to opioids. We conducted a prospective phase II study to investigate the efficacy and safety of 5-day continuous intravenous infusion (CIVI) of Ketamine in terminally ill cancer patients with refractory cancer pain.

METHODS

Hospitalized terminally ill cancer patients with refractory cancer pain were enrolled. Refractory cancer pain was indicated by requirements for 4 or more rescue opioids or pain intensity using numerical rating scale > personalized pain goal (PPG) despite of intravenous morphine equivalent daily dose (IV MEDD) ≥ 120 mg/day. The CIVI of ketamine was increased from .05 mg/kg/hour to .5 mg/kg/hour by .05 every 8 hours if pain intensity exceeded PPG or if number of rescue opioids ≥2 during prior 8 hours was required. The primary end-point was overall pain response rate, which indicates complete response (both rescue opioid ≤3/day and pain intensity ≤ PPG) plus partial response (rescue opioid ≤3/day), without unacceptable toxicities.

RESULTS

Among 21 eligible patients enrolled between September 2019 and January 2023, 20 were analyzed. Most pain mechanisms were mixed type (n = 15, 75%), with neuropathic component (n = 17, 85%). The baseline background opioids were IV MEDD 186 mg/24hour (range, 124-592), number of rescue opioids was 6 (IQR, 5-9), and median PPG was 4 (IQR, 3-4). The overall pain response rate was 50% (n = 10) including 40% (n = 8) for complete pain response and 10% (n = 2) for partial pain response.

CONCLUSION

This study showed efficacy of gradually increasing CIVI of ketamine for terminally ill cancer patients with refractory cancer pain. CIVI of ketamine could be a useful tool in these patients considering the limited treatment options. (NCT03362073, Initial Release: November 15, 2017).

Opioid analgesics for nociceptive cancer pain: A comprehensive review

Pain is one of the most burdensome symptoms in people with cancer, and opioid analgesics are considered the mainstay of cancer pain management. For this review, the authors evaluated the efficacy and toxicities of opioid analgesics compared with placebo, other opioids, nonopioid analgesics, and nonpharmacologic treatments for background cancer pain (continuous and relatively constant pain present at rest), and breakthrough cancer pain (transient exacerbation of pain despite stable and adequately controlled background pain). They found a paucity of placebo-controlled trials for background cancer pain, although tapentadol or codeine may be more efficacious than placebo (moderate-certainty to low-certainty evidence). Nonsteroidal anti-inflammatory drugs including aspirin, piroxicam, diclofenac, ketorolac, and the antidepressant medicine imipramine, may be at least as efficacious as opioids for moderate-to-severe background cancer pain. For breakthrough cancer pain, oral transmucosal, buccal, sublingual, or intranasal fentanyl preparations were identified as more efficacious than placebo but were more commonly associated with toxicities, including constipation and nausea. Despite being recommended worldwide for the treatment of cancer pain, morphine was generally not superior to other opioids, nor did it have a more favorable toxicity profile. The interpretation of study results, however, was complicated by the heterogeneity in the study populations evaluated. Given the limited quality and quantity of research, there is a need to reappraise the clinical utility of opioids in people with cancer pain, particularly those who are not at the end of life, and to further explore the effects of opioids on immune system function and quality of life in these individuals.

Should Buprenorphine Be Considered a First-Line Opioid for the Treatment of Moderate to Severe Cancer Pain?

Cancer pain remains a significant problem worldwide, affecting more than half of patients receiving anti-cancer treatment and most patients with advanced disease. Opioids remain the cornerstone of therapy, and morphine, given its availability, multiple formulations, price, and evidence base, is typically considered the first-line treatment for moderate to severe cancer pain. Buprenorphine has emerged in recent decades as an alternative opioid for treating chronic pain and substance use disorder (SUD). However, it remains controversial whether buprenorphine should be considered a first-line opioid for moderate to severe cancer pain. In this "Controversies in Palliative Care" article, three expert clinicians independently answer this question. Specifically, each group provides a synopsis of the key studies that inform their thought process, share practical advice on their clinical approach, and highlight the opportunities for future research. All three groups agree that there is a place for the use of buprenorphine as a first-line opioid in cancer pain. Specifically, they mention populations of elderly patients, patients with renal failure, and those with (SUD). They also underscore many unique and favorable characteristics of buprenorphine, such as the low risk for respiratory depression, lack of adverse effects on testosterone levels in men, no risk of serotonin syndrome when combined with antidepressants, and ease of use given its transdermal, transmucosal, and sublingual formulations. However, further studies are needed to guide the use of buprenorphine for cancer pain-primarily randomized clinical trials (RCTs) comparing buprenorphine with other opioids in various pain syndromes.

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.

Effects of opioid rotation to buprenorphine/naloxone on pain, pain thresholds, pain tolerance, and quality of life in patients with chronic pain and opioid use disorder

ABSTRACT

Long-term opioid use in patients with chronic noncancer pain (CNCP) can lead to opioid use disorder (OUD) and has been associated with hyperalgesia and reduced quality of life (QoL). Studies suggest antihyperalgesic properties of buprenorphine, and buprenorphine or naloxone (BuNa) has shown beneficial effects on QoL in patients with OUD without CNCP. This study investigated the added value of BuNa in patients with CNCP with OUD on self-reported pain, pain thresholds, pain tolerance, and QoL. In the current study, 43 outpatients with CNCP and OUD were included for inpatient conversion from full μ-receptor agonist opioids to BuNa. Self-reported pain, pain thresholds, pain tolerance, and QoL were determined at baseline and after 2 months of follow-up, using, respectively, a Visual Analogue Scale (VAS-pain and VAS-QoL), quantitative sensory testing, and EuroQol-5 dimensions. In total, 37 participants completed the protocol, and their data were analyzed. The mean VAS-pain score decreased from 51.3 to 37.2 (27.5%, F = 3.3; P = 0.044), whereas the pressure pain threshold and electric pain threshold or tolerance increased after substitution (F = 7.8; P = 0.005 and F = 44.5; P < 0.001, respectively), as well as QoL (EuroQol-5 dimensions questionnaire: F = 10.4; P = 0.003 and VAS-QoL: F = 4.4; P = 0.043). We found that conversion of full μ-receptor agonists to BuNa, in patients with CNCP with OUD, was accompanied with lower self-reported pain, higher pain thresholds, higher pain tolerance, and improved QoL. Despite several study limitations, these data suggest that BuNa might be of value in patients with CNCP with OUD. Future studies should investigate long-term effects of BuNa in randomized trials.

Regular dosing compared with as-needed dosing of opioids for management of chronic cancer pain: systematic review and meta-analysis

Opioids are the recommended form of analgesia for patients with persistent cancer pain, and regular dosing "by the clock" is advocated in many international guidelines on cancer pain management. The development of sustained-release opioid preparations has made regular dosing easier for patients. However, patients report that the intensity and impact of their cancer pain varies considerably day to day, and many try to find a trade-off between acceptable pain control and impact of cognitive (and other) adverse effects on daily activities. In acute care settings, (eg, postoperative) as-needed dosing and other opioid-sparing approaches have resulted in better patient outcomes compared with regular dosing. The aim of this study was to determine whether regular dosing of opioids was superior to as-needed dosing for persistent cancer pain. We systematically searched for randomised controlled trials that directly compared pain outcomes from regular dosing of opioids with as-needed dosing in adult cancer patients. We identified 4347 records, 25 randomised controlled trials meet the inclusion criteria, 9 were included in the review, and 7 of these included in meta-analysis. We found no clear evidence demonstrating superiority of regular dosing of opioids compared with as-needed dosing in persistent cancer pain, and regular dosing was associated with significantly higher total opioid doses. There was, however, a paucity of trials directly answering this question, and low-quality evidence limits the conclusions that can be drawn. It is clear that further high-quality clinical trials are needed to answer this question and to guide clinical practice.

A narrative review of buprenorphine in adult cancer pain

INTRODUCTION

Adult cancer pain is a disease state battled on a global scale. Proper pain management is essential to prevent health complications and promote patient well-being. Due to the opioid misuse crisis in the United States, providers are looking for alternatives to traditional opioids used for adult cancer pain. Buprenorphine has a unique pharmacologic profile, allowing it to be delivered in noninvasive ways; thus, it offers an alternative to traditional options. Randomized controlled trials have shown improved pain scores with transdermal buprenorphine, and they showed reductions in pain scores and increased improvement in quality of life scores versus other opioids. Sublingual buprenorphine has more limited, but promising data for reducing cancer pain.

AREAS COVERED

We provide a narrative review of pathophysiological pathways of pain in cancer, how they are treated, and the unique properties of buprenorphine. Guidelines addressing pain management during cancer treatment are assessed to identify buprenorphine's place in therapy. Recent literature reporting efficacy and safety of buprenorphine use in pain management during cancer treatment will be presented.

EXPERT OPINION

Current literature shows strong data for transdermal buprenorphine and promising data for sublingual buprenorphine. With this evidence, buprenorphine could have a more expanded role in managing adult cancer pain.

Chronic Pain Management in Head and Neck Oncology

Pain is epidemic in patients with head and neck cancer. Providers involved in the care of patients with head and neck cancer should be able to describe the common pain syndromes experienced by these patients, identify patients at risk of pain, and provide multimodal treatment of chronic pain. Treatment of chronic pain encompasses analgesic medications; adjuvant pharmacotherapy, including antidepressants and anticonvulsants; interventional techniques; as well as integrative medicine.

A Narrative Pharmacological Review of Buprenorphine: A Unique Opioid for the Treatment of Chronic Pain

Buprenorphine is a Schedule III opioid analgesic with unique pharmacodynamic and pharmacokinetic properties that may be preferable to those of Schedule II full μ-opioid receptor agonists. The structure of buprenorphine allows for multimechanistic interactions with opioid receptors μ, δ, κ, and opioid receptor-like 1. Buprenorphine is considered a partial agonist with very high binding affinity for the μ-opioid receptor, an antagonist with high binding affinity for the δ- and κ-opioid receptors, and an agonist with low binding affinity for the opioid receptor-like 1 receptor. Partial agonism at the μ-opioid receptor does not provide partial analgesia, but rather analgesia equivalent to that of full μ-opioid receptor agonists. In addition, unlike full μ-opioid receptor agonists, buprenorphine may have a unique role in mediating analgesic signaling at spinal opioid receptors while having less of an effect on brain receptors, potentially limiting classic opioid-related adverse events such as euphoria, addiction, or respiratory depression. The pharmacokinetic properties of buprenorphine are also advantageous in a clinical setting, where metabolic and excretory pathways allow for use in patients requiring concomitant medications, the elderly, and those with renal or hepatic impairment. The unique pharmacodynamic and pharmacokinetic properties of buprenorphine translate to an effective analgesic with a potentially favorable safety profile compared with that of full μ-opioid receptor agonists for the treatment of chronic pain.

Buprenorphine/naloxone induction for treatment of acute on chronic pain using a micro-dosing regimen: A case report

Background: Due to its unique pharmacologic properties, efficacy as an analgesic, and role as a first-line medication for the treatment of opioid use disorder, sublingual buprenorphine has emerged as a treatment for patients with concurrent chronic pain and opioid use disorders. One challenge to utilizing buprenorphine is that precipitated opioid withdrawal can result if this medication is initiated in the presence of other opiates with lesser binding affinities. Micro-dosing induction regimens utilize a slower titration to avoid the need for a period of abstinence from other opiates and decrease the risk of precipitated withdrawal.

Aims: The aim of this article is to present a case where a standardized micro-dosing induction regimen was used to transition a patient from other opiate analgesia to a sublingual formulation of buprenorphine/naloxone.

Methods: This case took place on an inpatient neurosurgical unit of a Canadian tertiary-care city hospital. Written informed consent was collected prior to a detailed chart review.

Results: Here we present a case of a postoperative neurosurgical inpatient who was referred to our team for pain management in the context of chronic pain and a past history of opioid use disorder. She was successfully transitioned to buprenorphine/naloxone, replacing all other opioid analgesia, without a period of opioid withdrawal using a micro-dosing induction regimen.

Conclusions: Sublingual buprenorphine/naloxone can be safe and effective for treatment of chronic pain, particularly for those with past or current opioid use disorder. Micro-dosing provides a preferable induction strategy for patients who are not able to tolerate the requirement for moderate opioid withdrawal prior to initiation with existing regimens.

Treating Chronic Pain: An Overview of Clinical Studies Centered on the Buprenorphine Option

The buprenorphine receptor binding profile is unique in that it binds to all three major opioid receptors (mu, kappa, delta), and also binds to the orphan-like receptor, the receptor for orphanin FQ/nociceptin, with lower affinity. Within the mu receptor group, buprenorphine analgesia in rodents is dependent on the recently discovered arylepoxamide receptor target in brain, which involves a truncated 6-transmembrane mu receptor gene protein, distinguishing itself from morphine and most other mu opioids. Although originally designed as an analgesic, buprenorphine has mainly been used for opioid maintenance therapy and only now is increasingly recognized as an effective analgesic with an improved therapeutic index relative to certain potent opioids. Albeit a second-, third-, or fourth-line analgesic, buprenorphine is a reasonable choice in certain clinical situations. Transdermal patches and buccal film formulations are now commercially available as analgesics. This review discusses buprenorphine pharmacodynamics and pharmacokinetics, use in certain populations, and provides a synopsis of systematic reviews and randomized analgesic trials. We briefly discuss postoperative management in patients receiving buprenorphine maintenance therapy, opioid equivalence to buprenorphine, rotations to buprenorphine from other opioids, and clinical relevance of buprenorphine-related QTc interval changes.

A Comparative Study of Transdermal Buprenorphine and Oral Morphine in the Treatment of Chronic Pain of Malignant Origin

Background and Objective:

The study was designed to compare the efficacy and adverse effects of buprenorphine transdermal (TD) against oral morphine in pain management of cancer patient.

Methods:

A randomized open-labeled prospective study was done in palliative cancer pain clinic in a tertiary care medical college between August 2017 and January 2018, to compare the efficacy (pain assessed by VAS) and adverse events (CTCAEv4) between arm A, buprenorphine TD, (20 μg/h, extended 7 days formulation) and arm B, oral morphine (10mg immediate releasing formulation). Patients with solid tumour malignancies with VAS score >40 (moderate to severe pain) were included in study.

Results:

63 patients were analyzed. Commonest primary cancers were breast in females and head and neck in male individuals in both arms. Initial VAS score of arm A and arm B were 81.25 and 82.26 respectively. By 1st week, 11 arm A patients were relieved from pain. Another 17 patients of arm A became pain free by 2nd week, total dose of 40 μg/h. Only 4 patients needed 60 μg/h for pain relief. In arm B, 2 patients were relieved by 1 week with total 30mg/day morphine, 11patients were relieved with 60 mg/day by 2nd week and 12 patients with 90 mg/day. 6 patients were relieved with 120 mg/day dose at the end of 4^th week. Nausea and constipation were stastically higher in Arm B compared to that of Arm-A.

Conclusions:

TD Buprenorphine had similar efficacy with oral morphine, with better toxicity profile and better compliance.

Evidence-Based Palliative Care 13 Years On: Has anything changed?

There is a paucity of data on whether interventions in individual palliative care units are evidence-based. Thirteen years ago an initial study evaluated the evidence base of interventions in palliative care. Using similar methodology in the present study, we evaluated the evidence for interventions performed in an inpatient palliative care setting, looking at level of evidence as well as quality and outcome of evidence. More than half of all the interventions (47 interventions, 59 percent) we looked at in a Brisbane, Australia, inpatient palliative care setting were based on a high level of evidence in the form of systematic reviews of randomized controlled trials (level I or level II). There were only a few interventions (10 percent) for which no evidence could be retrieved. Our results show that the evidence base for interventions in palliative care continues to evolve, but that there are still areas for which further high-quality studies are needed.

The switch from buprenorphine to tapentadol: is it worth?

Opioid analgesia continues to be the primary pharmacologic intervention for managing acute pain and malignant pain in both hospitalized and ambulatory patients. The increasing use of opioids in chronic nonmalignant pain is more problematic. Opioid treatment is complicated with the risks raised by adverse effects, especially cognitive disturbance, respiratory depression but also the risk of tolerance, opioid abuse and drug-disease interactions. Despite the growing number of available opioids within the last years, adequate trials of opioid rotation are lacking and most of the information is anecdotal. This article reviews the clinical evidence surrounding the switch from transdermal buprenorphine to tapentadol in malignant and non-malignant pain. Tapentadol acts on both the μ-opioid receptors (MOR) and on the neuronal reuptake of noradrenaline with a limited usefulness in acute pain management while buprenorphine is a mixed agonist-antagonist, and both present some advantages over other opioids. Both drugs show particular pharmacodynamic and pharmacokinetic properties which reduce the risks of development of tolerance, opioid abuse, diversion and determine fewer hormone changes than the "classical opioids" making these opioids more attractive than other opioids in long term opioid treatment. However, in the absence of powered clinical trials, the evidence to support the method used for transdermal buprenorphine rotation to tapentadol is weak.

Use of immediate-release opioids as supplemental analgesia during management of moderate-to-severe chronic pain with buprenorphine transdermal system

Background

The buprenorphine transdermal system (BTDS) is approved in the US for the management of chronic pain. Due to its high affinity for μ-opioid receptors with a slow dissociation profile, buprenorphine may potentially displace or prevent the binding of competing μ-opioid-receptor agonists, including immediate-release (IR) opioids, in a dose-dependent manner. Health care professionals may assume that the use of IR opioids for supplemental analgesia during BTDS therapy is not acceptable.

Materials and methods

This post hoc analysis evaluated the use of IR opioids as supplemental analgesia during the management of moderate–severe chronic pain with BTDS at 52 US sites (BUP3015S, NCT01125917). Patients were categorized into IR-opioid and no-IR-opioid groups. At each visit of the extension phase, adverse events, concomitant medications, and information from the Brief Pain Inventory (BPI) were recorded.

Results

The most common supplemental IR opioids prescribed during BTDS treatment (n=354) were hydrocodone–acetaminophen and oxycodone–acetaminophen. The mean daily dose of IR opioids (morphine equivalents) for supplemental analgesia was 22 mg. At baseline, BPI – pain intensity and BPI – interference scores were higher for patients in the IR-opioid group. In both treatment groups, scores improved by week 4, and then were maintained throughout 6 months of the open-label extension trial. The incidence of treatment-emergent adverse events was similar in both groups.

Conclusion

Patients who were prescribed IR opioids reported lower scores for BPI pain intensity and pain interference to levels similar to patients receiving BTDS without IR opioids, without increasing the rate or severity of treatment-emergent adverse events. Patients prescribed concomitant use of IR opioids with BTDS had greater treatment persistence. The results of this post hoc analysis provide support for the concomitant use of IR opioids for supplemental analgesia during the management of moderate–severe chronic pain with BTDS.

Assessment of Transdermal Buprenorphine Patches for the Treatment of Chronic Pain in a UK Observational Study

BACKGROUND

Opioids provide effective analgesia for moderate-to-severe, chronic pain. Transdermal buprenorphine (TDB) is available in the UK as weekly, lower-dose (5-20 μg/h) patches and twice-weekly, higher dose (35-70 μg/h) patches. This prospective, observational, multicenter study of patients with various chronic pain conditions assessed the safety, perceptions, and discontinuation of treatment with TDB in a real-world, non-interventional setting (ClinicalTrials.gov study ID: NCT01225861).

METHODS

Patients aged ≥18 years who were already receiving or initiating treatment with TDB were recruited in the UK during routine clinical visits and were followed for 6 visits or 9 months (whichever came first). Self-reported treatment adherence, patient satisfaction, and safety data were collected at each study visit.

RESULTS

Of 465 patients, 272 were already receiving 7-day TDB at the study start (TDB experienced), 146 were TDB naïve, and 47 were prescribed twice-weekly TDB. Most patients were female (72.9 %) and overweight/obese (body mass index ≥25: 75.3 %). The median age was 67 years, and the mean duration of pain was 11.1 years. Arthritis/other musculoskeletal disorders (39.6 %) were the most common causes of pain. Mild adverse events were commonly reported. Skin irritations, which were most frequent in 7-day TDB-experienced patients (45.6 %), rarely resulted in treatment discontinuation (8.8 %). Nearly all patients used TDB in accordance with treatment recommendations. Most patients reported that TDB was 'effective'/'very effective' at relieving pain and were 'satisfied'/'very satisfied' with TDB therapy.

CONCLUSION

In everyday clinical practice, TDB was well tolerated and patients were satisfied with their therapy. Self-reported adherence to TDB was very high, and adverse events rarely resulted in treatment discontinuation. Opportunities were identified to limit common adverse events associated with TDB.

The effectiveness of buprenorphine for treating cancer pain: an abridged Cochrane review

OBJECTIVES

To assess the effectiveness and tolerability of buprenorphine for cancer pain in adults and children.

METHODS

We searched CENTRAL, MEDLINE, EMBASE, ISI Web of Science, ISI BIOSIS, ClinicalTrials.gov, metaRegister of Controlled Trials, WHO International Clinical Trials Registry Platform and the Proceedings of the Congress of the European Federation of International Association for the Study of Pain to early 2015.

RESULTS

We included 19 randomised controlled trials comparing buprenorphine with placebo, buprenorphine or another active drug for cancer pain. The trials included 1421 patients and examined 16 different intervention comparisons. Of the 11 studies that compared buprenorphine to another drug, 5, 3 and 3 studies, respectively, found that buprenorphine was superior, no different or inferior to the alternative treatment in side effects profile or patient preference/acceptability. Pain intensity ratings did not differ significantly between intramuscular buprenorphine and buprenorphine suppository, although intramuscular treatment was associated with more adverse events (1 study). One study found faster onset of pain relief after sublingual than subdermal buprenorphine, with similar analgesia duration and adverse event rates. 2 studies found transdermal buprenorphine superior to placebo, whereas a third study found no difference between placebo and different doses of transdermal buprenorphine. No clear dose-response relationship was found for transdermal buprenorphine. The quality of this evidence base was limited by under-reporting, small sample sizes and attrition.

CONCLUSIONS

Buprenorphine might be considered as a fourth-line option compared with the more standard therapies of morphine, oxycodone and fentanyl, and even then it would only be suitable for some patients.

Buprenorphine for treating cancer pain

BACKGROUND

Many patients with cancer experience moderate to severe pain that requires treatment with strong analgesics. Buprenorphine, fentanyl and morphine are examples of strong opioids used for cancer pain relief. However, strong opioids are ineffective as pain treatment in all patients and are not well-tolerated by all patients. The aim of this Cochrane review is to assess whether buprenorphine is associated with superior, inferior or equal pain relief and tolerability compared to other analgesic options for patients with cancer pain.

OBJECTIVES

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

SEARCH METHODS

We searched CENTRAL (the Cochrane Library) issue 12 or 12 2014, MEDLINE (via OVID) 1948 to 20 January 2015, EMBASE (via OVID) 1980 to 20 January 2015, ISI Web of Science (SCI-EXPANDED & CPCI-S) to 20 January 2015, ISI BIOSIS 1969 to 20 January 2015. We also searched ClinicalTrials.gov (http://clinicaltrials.gov/; metaRegister of Controlled Trials (mRCT) (http://www.controlled-trials.com/mrct/), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal (http://apps.who.int/trialsearch/) and the Proceedings of the Congress of the European Federation of International Association for the Study of Pain (IASP; via European Journal of Pain Supplements) on 16 February 2015. We checked the bibliographic references of identified studies as well as relevant studies and systematic reviews to find additional trials not identified by the electronic searches. We contacted authors of included studies for other relevant studies.

SELECTION CRITERIA

We included randomised controlled trials, with parallel-group or crossover design, comparing buprenorphine (any formulation and any route of administration) with placebo or an active drug (including buprenorphine) for cancer background pain in adults and children.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data pertaining to study design, participant details (including age, cancer characteristics, previous analgesic medication and setting), interventions (including details about titration) and outcomes, and independently assessed the quality of the included studies according to standard Cochrane methodology. As it was not feasible to meta-analyse the data, we summarised the results narratively. We assessed the overall quality of the evidence for each outcome using the GRADE approach.

MAIN RESULTS

In this Cochrane review we identified 19 relevant studies including a total of 1421 patients that examined 16 different intervention comparisons.Of the studies that compared buprenorphine to another drug, 11 studies performed comparative analyses between the randomised groups, and five studies found that buprenorphine was superior to the comparison treatment. Three studies found no differences between buprenorphine and the comparison drug, while another three studies found treatment with buprenorphine to be inferior to the alternative treatment in terms of the side effects profile or patients preference/acceptability.Of the studies that compared different doses or formulations/routes of administration of buprenorphine, pain intensity ratings did not differ significantly between intramuscular buprenorphine and buprenorphine suppository. However, the average severity of dizziness, nausea, vomiting and adverse events as a total were all significantly higher in the intramuscular group relatively to the suppository group (one study).Sublingual buprenorphine was associated with faster onset of pain relief compared to subdermal buprenorphine, with similar duration analgesia and no significant differences in adverse event rates reported between the treatments (one study).In terms of transdermal buprenorphine, two studies found it superior to placebo, whereas a third study found no difference between placebo and different doses of transdermal buprenorphine.The studies that examined different doses of transdermal buprenorphine did not report a clear dose-response relationship.The quality of this evidence base was limited by under-reporting of most bias assessment items (e.g., the patient selection items), by small sample sizes in several included studies, by attrition (with data missing from 8.2% of the enrolled/randomised patients for efficacy and from 14.6% for safety) and by limited or no reporting of the expected outcomes in a number of cases. The evidence for all the outcomes was very low quality.

AUTHORS' CONCLUSIONS

Based on the available evidence, it is difficult to say where buprenorphine fits in the treatment of cancer pain with strong opioids. However, it might be considered to rank as a fourth-line option compared to the more standard therapies of morphine, oxycodone and fentanyl, and even there it would only be suitable for some patients. However, palliative care patients are often heterogeneous and complex, so having a number of analgesics available that can be given differently increases patient and prescriber choice. In particular, the sublingual and injectable routes seemed to have a more definable analgesic effect, whereas the transdermal route studies left more questions.

Buprenorphine for treating cancer pain

BACKGROUND

Many patients with cancer experience moderate to severe pain that requires treatment with strong analgesics. Buprenorphine, fentanyl and morphine are examples of strong opioids used for cancer pain relief. However, strong opioids are ineffective as pain treatment in all patients and are not well-tolerated by all patients. The aim of this Cochrane review is to assess whether buprenorphine is associated with superior, inferior or equal pain relief and tolerability compared to other analgesic options for patients with cancer pain.

OBJECTIVES

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

SEARCH METHODS

We searched CENTRAL (the Cochrane Library) issue 12 or 12 2014, MEDLINE (via OVID) 1948 to 20 January 2015, EMBASE (via OVID) 1980 to 20 January 2015, ISI Web of Science (SCI-EXPANDED & CPCI-S) to 20 January 2015, ISI BIOSIS 1969 to 20 January 2015. We also searched ClinicalTrials.gov (http://clinicaltrials.gov/; metaRegister of Controlled Trials (mRCT) (http://www.controlled-trials.com/mrct/), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal (http://apps.who.int/trialsearch/) and the Proceedings of the Congress of the European Federation of International Association for the Study of Pain (IASP; via European Journal of Pain Supplements) on 16 February 2015. We checked the bibliographic references of identified studies as well as relevant studies and systematic reviews to find additional trials not identified by the electronic searches. We contacted authors of included studies for other relevant studies.

SELECTION CRITERIA

We included randomised controlled trials, with parallel-group or crossover design, comparing buprenorphine (any formulation and any route of administration) with placebo or an active drug (including buprenorphine) for cancer background pain in adults and children.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data pertaining to study design, participant details (including age, cancer characteristics, previous analgesic medication and setting), interventions (including details about titration) and outcomes, and independently assessed the quality of the included studies according to standard Cochrane methodology. As it was not feasible to meta-analyse the data, we summarised the results narratively. We assessed the overall quality of the evidence for each outcome using the GRADE approach.

MAIN RESULTS

In this Cochrane review we identified 19 relevant studies including a total of 1421 patients that examined 16 different intervention comparisons.Of the studies that compared buprenorphine to another drug, 11 studies performed comparative analyses between the randomised groups, and five studies found that buprenorphine was superior to the comparison treatment. Three studies found no differences between buprenorphine and the comparison drug, while another three studies found treatment with buprenorphine to be inferior to the alternative treatment in terms of the side effects profile or patients preference/acceptability.Of the studies that compared different doses or formulations/routes of administration of buprenorphine, pain intensity ratings did not differ significantly between intramuscular buprenorphine and buprenorphine suppository. However, the average severity of dizziness, nausea, vomiting and adverse events as a total were all significantly higher in the intramuscular group relatively to the suppository group (one study).Sublingual buprenorphine was associated with faster onset of pain relief compared to subdermal buprenorphine, with similar duration analgesia and no significant differences in adverse event rates reported between the treatments (one study).In terms of transdermal buprenorphine, two studies found it superior to placebo, whereas a third study found no difference between placebo and different doses of transdermal buprenorphine.The studies that examined different doses of transdermal buprenorphine did not report a clear dose-response relationship.The quality of this evidence base was limited by under-reporting of most bias assessment items (e.g., the patient selection items), by small sample sizes in several included studies, by attrition (with data missing from 8.2% of the enrolled/randomised patients for efficacy and from 14.6% for safety) and by limited or no reporting of the expected outcomes in a number of cases. The evidence for all the outcomes was very low quality.

AUTHORS' CONCLUSIONS

Based on the available evidence, it is difficult to say where buprenorphine fits in the treatment of cancer pain with strong opioids. However, it might be considered to rank as a fourth-line option compared to the more standard therapies of morphine, oxycodone and fentanyl, and even there it would only be suitable for some patients. However, palliative care patients are often heterogeneous and complex, so having a number of analgesics available that can be given differently increases patient and prescriber choice. In particular, the sublingual and injectable routes seemed to have a more definable analgesic effect, whereas the transdermal route studies left more questions.

Buprenorphine for Cancer Pain

Buprenorphine (BUP) is a semisynthetic derivative of the opium alkaloid thebaine found in the poppy Papaver somniferum. Its chemical structure contains the morphine structure but differs by having a cyclopropylmethyl group. Buprenorphine is a potent µ opioid agonist. Buprenorphine undergoes extensive first-pass metabolism in the liver and gut. The development of a transdermal BUP formulation in 2001 led to its evaluation in cancer pain. This article provides the practitioner with an update on the current role of BUP in cancer care. It highlights data suggesting effectiveness in various types of cancer pain. The article reviews pharmacology, routes of administration, adverse effects, drug interactions, and cost considerations.

Principles of Opioid Use in Cancer Pain

The management of pain is an essential aspect of comprehensive cancer care. Positive outcomes can be achieved in most patients with widely available therapies. There is a broad consensus that opioid-based pharmacotherapy is the first-line strategy for the treatment of moderate or severe chronic pain in populations with active disease, and treatment guidelines have been developed from the known pharmacology of these drugs, extant data, and extensive clinical experience. This article describes the major opioid analgesics available for the treatment of cancer-related pain and reviews the key elements for safe and effective prescribing, including selection of the best drug and route, approaches to titration and long-term administration of baseline and supplemental doses, rotation from one drug to another in poorly responsive patients, and management of opioid risks.

Systematic review of adverse events of buprenorphine patch versus fentanyl patch in patients with chronic moderate-to-severe pain

SUMMARY This systematic review compares convenience of administration, adverse events and tolerability of buprenorphine patch with fentanyl patch in patients with chronic pain. Methods of quantitative and qualitative research were combined. Seventeen databases were searched up to December 2010. A total of 49 unique trials (56 publications) were included. Patients regarded the use of patches, both transdermal buprenorphine and fentanyl, as easy and convenient. Compared with buprenorphine patch, fentanyl can cause more cases of constipation and could lead to a higher number of serious adverse events. There were no differences between buprenorphine patch and fentanyl patch regarding dizziness, somnolence, nausea and treatment discontinuation. Overall, transdermal administration of buprenorphine and fentanyl can be seen as an alternative pathway for delivering these drugs. Use of transdermal buprenorphine might be favorable in certain groups of patients, such as renally impaired, elderly and immunosuppressed patients.

A meta-analysis of efficacy and tolerability of buprenorphine for the relief of cancer pain

This study aimed to synthesize available evidence on the analgesic efficacy of buprenorphine in treating cancer pain and related adverse effects. We searched electronic databases for randomized controlled trials, assessing the efficacy of buprenorphine, regardless of delivery system. The primary endpoints were patient-reported 'pain intensity' and 'pain relief'. Statistical heterogeneity among included studies was assessed with the I (2) test. The summary relative risk (RR) and 95% CI were derived, if two or more studies reported the similar outcome. Sixteen RCTs (n = 1329) with buprenorphine were included: 8 transdermal (TD), 5 sublingual (SL), 2 intramuscular injection (IM) and 1 subcutaneous infusion (SC) studies; with both SL and IM routes being assessed in one study. Only a few studies reported the same outcome in a similar way, creating difficulty for pooling of the outcome data. Many studies had a high risk of bias. In 2 studies (n = 241), the 'global impression change' was significantly different between TD buprenorphine and the combined placebo and morphine (RR 1.35, 95% CI 1.14-1.59; I (2): 42%); the 'number-needed-to-treat' (NNT) was 4.9 (95% CI: 3.1-10.9). In 2 studies (n = 331), 'requirement for rescue SL buprenorphine' was comparable between TD buprenorphine and placebo (RR 1.25, 95% CI 0.71-2.18; I (2) : 40%). In 2 studies (n = 141), 'incidence of nausea' was less in TD buprenorphine (RR: 0.38, 95% CI: 0.2-0.71, I (2): 0%, NNT: 9.3, 5.6-28.5). Due to the small number of participants in a small number of studies, the results of the present review provide insufficient evidence to position adequately the use of buprenorphine in treatment of cancer pain. Large multicenter RCTs that compare TD buprenorphine with standard analgesic treatment is needed to position TD buprenorphine in the therapeutic armamentarium of cancer pain treatment.

Systematic review of efficacy and safety of buprenorphine versus fentanyl or morphine in patients with chronic moderate to severe pain

OBJECTIVE

To systematically assess efficacy and safety of buprenorphine patch versus fentanyl patch in patients with chronic moderate to severe pain.

METHODS

Fifteen databases were searched up to December 2010. Randomised and quasi-randomised trials assessing the efficacy in patients with chronic pain were included. Quantitative methods for data synthesis were used and two network meta-analyses were conducted.

RESULTS

Fourteen unique trials (17 publications) were included. No head-to-head randomised trials of buprenorphine patch compared with fentanyl patch were identified. Therefore, less robust evidence from indirect comparisons was used. Results from a network meta-analysis of non-enriched designs (eight trials), using trials versus placebo and trials versus morphine for indirect comparisons, indicated that transdermal fentanyl, in comparison with transdermal buprenorphine, showed significantly more nausea (odds ratio [OR] 4.66, 95% confidence interval (CI) 1.07 to 20.39), a significantly higher number of treatment discontinuations due to adverse events (OR 5.94, 95% CI 1.78 to 19.87), and non-significant differences on all other outcomes, including pain measures. In comparison with morphine, transdermal buprenorphine had a significantly higher decrease of pain intensity (MD [mean difference] -16.20, 95% CI -28.92 to -3.48) while morphine caused more cases of constipation (OR 7.50, 95% CI 1.45 to 38.85) and a significantly higher number of treatment discontinuations due to adverse events (OR 5.80, 95% CI 1.68 to 20.11). All other outcomes showed non-significant differences between transdermal buprenorphine and morphine. The results were similar when also including six trials using enriched designs with the exception of more cases of vomiting for fentanyl (OR 17.32, 95% CI 4.43 to 67.71) and morphine (OR 15.85, 95% CI 3.92 to 64.13) compared to buprenorphine.

CONCLUSIONS

The findings indicate comparability of transdermal buprenorphine and transdermal fentanyl for pain measures with significantly fewer adverse events (nausea and treatment discontinuation due to adverse events) caused by transdermal buprenorphine.

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.

Transdermal buprenorphine for the treatment of cancer pain: results from a multicenter, observational, post-marketing study in Spain (RELIEF study)

SUMMARY 

AIM

This study evaluated health outcomes in patients with cancer pain during treatment with transdermal buprenorphine, including quality of life, effectiveness, tolerability, and functional consequences for patients and their carers.

METHODS

In this 3-month, noncomparative, multicenter, observational study performed in a normal clinical practice setting in Spain, patients received transdermal buprenorphine 37, 52.5 or 70 µg/h, with patches changed every 96 h. The effect of transdermal buprenorphine on quality of life (primary study focus) was assessed using the Visual Analog Scale (VAS) component of the EuroQol 5 Dimensions™ (EQ-5D). In addition, pain (assessed using the Brief Pain Inventory - Short Form [BPI-SF] and VAS-pain), the impact of pain on patients and carers (assessed using the Beck Depression Inventory, sleep quality analysis, VAS-patient limitation, VAS-carer limitation and the Palliative Care Scale), patient's use of health resources, patient satisfaction, and tolerability, were evaluated.

RESULTS

Of 116 patients entering the study, 42 completed the 3-month study period. Five patients withdrew due to adverse events. The two main reasons for study discontinuation were nontreatment-related death (27.1%) and lost to follow-up (18.8%). The mean age was 62.9 years and the mean baseline duration of pain was 7.78 weeks. In the month prior to starting transdermal buprenorphine, 80% of patients had received at least one nonopioid analgesic medication; 21% had received an opioid analgesic (most commonly tramadol). The most common dose of transdermal buprenorphine used was 35 µg/h. The mean improvement from baseline in the EQ-5D VAS score among 65 patients with data was 15.20 ± 24.96 (p < 0.0001). EQ-5D descriptive parameters also improved during the study (not statistically significant). Mean improvements in BPI scores for worst pain (3.76) and average pain (3.03) were significant (p < 0.0001). The other measures of pain relief also supported transdermal buprenorphine as an effective analgesic. Sleep quality improved during the study. VAS scores (100 mm scale) for patient limitation and caregiver burden due to pain improved, with a significant mean change in VAS-carer limitation score (30.34; p < 0.0001). Adverse events were reported by ten (8.6%) patients, most commonly affecting the gastrointestinal system (vomiting [4.3% of patients], nausea [2.6%] and constipation [0.9%]). The majority of patients reported satisfaction with their analgesic treatment.

CONCLUSIONS

In this observational study in normal clinical practice, transdermal buprenorphine provided effective pain relief and was generally well tolerated by patients with cancer pain. It also improved quality of life for patients and reduced caregiver burden. Considering the high number of study discontinuations (mainly due to nontreatment-related death and lost to follow-up), the results of this study need to be evaluated with caution.

Systematic review of the role of alternative application routes for opioid treatment for moderate to severe cancer pain: an EPCRC opioid guidelines project

The European Palliative Care Research Collaboration is updating the EAPC recommendations on opioids in cancer pain management. A systematic literature search on Medline on the use of alternative routes for opioid application identified 242 papers, with 72 publications included in the final evaluation. Two or more alternative routes of opioid application were compared in 18 papers with a total of 674 patients. The best evidence base was available for the subcutaneous route. A comparison of subcutaneous and intravenous routes found no differences, confirming both routes as feasible, effective and safe. Efficacy and safety of the rectal route was comparable to the parenteral route. The side effect profile seemed to be very similar for the subcutaneous, intravenous, rectal or transdermal routes. Local side effects were reported for rectal application as well as for subcutaneous and transdermal administration. In conclusion, the systematic review found good evidence that subcutaneous administration of morphine or other opioids is an effective alternative for cancer patients if oral treatment is not possible. However, for a number of patients intravenous, rectal or transdermal therapy will offer a good alternative to the subcutaneous route. The review found no significant differences in efficacy or side effects between the alternative application routes.

Transdermal opioids as front line treatment of moderate to severe cancer pain: a systemic review

BACKGROUND

To assess the role of transdermal opioids as a front-line approach to moderate to severe cancer pain.

METHODS

A systematic review of the literature was performed by two authors. An analysis of the level of evidence and risk/benefit ratio was performed for all of the selected trials. A combined analysis of the included studies to assess the level of evidence, risk/benefit ratio and strength of the recommendations was performed to determine the place of transdermal opioids in the treatment of cancer when compared with oral morphine.

RESULTS

Thirteen papers were included in the analysis. The level of evidence was considered low for transdermal opioids (without distinction between transdermal fentanyl and transdermal buprenorphine) or transdermal fentanyl, and very low for transdermal buprenorphine. The risk/benefit ratio was considered uncertain for both transdermal opioids (fentanyl and buprenorphine) considered together and transdermal fentanyl or buprenorphine alone. The strength of the final recommendations (using the GRADE system) was weak negative for transdermal opioids (transdermal fentanyl plus transdermal buprenorphine) and transdermal fentanyl, and strong negative for transdermal buprenorphine.

CONCLUSIONS

The use of slow release oral morphine probably remains the preferred approach for these patients, with the use of transdermal opioids to be reserved for selected patients.

Management of opioid-induced nausea and vomiting in cancer patients: systematic review and evidence-based recommendations

The objectives were to review the existing literature on management of opioid-induced nausea and vomiting in cancer patients and summarize the findings into evidence-based recommendations. Systematic searches of MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were performed, using free text and MeSH/EMTREE search terms. The searches were limited to articles published in English from each database set-up date to 31 July 2009. Reference lists and relevant international conference proceedings were hand-searched. Fifty-five studies were identified, providing data on 5741 patients. The studies were classified into: (A) studies in which treatment of nausea/vomiting was the primary outcome (a total of 18 studies, of which eight studies specifically addressed opioid-induced emesis); and (B) studies in which nausea/vomiting were secondary or tertiary outcomes (37 studies). The existing evidence had several limitations, there was a lack of consistency and the overall quality was grade D. By applying the principles of the Grading of Recommendations Assessment, Development and Evaluations (GRADE) system, three weak recommendations were formulated. The current evidence is too limited to give evidence-based recommendations for the use of antiemetics for opioid-induced nausea or vomiting in cancer patients. The evidence suggests that nausea and vomiting in cancer patients receiving an opioid might be reduced by changing the opioid or opioid administration route. The evidence was also too limited to prioritize between symptomatic treatment and adjustment of the opioid treatment.

Can morphine still be considered to be the standard for treating chronic pain? A systematic review including pair-wise and network meta-analyses

OBJECTIVE

For chronic pain treatment many health care authorities consider morphine to be the reference standard for strategic decisions in pain therapy. Although morphine's effectiveness is clear and its cost is low, it's unclear whether morphine should remain the first choice or reference treatment.

RESEARCH DESIGN AND METHODS

We performed a systematic review to evaluate the evidence available to support the position of morphine as the reference standard for step III opioids based on efficacy and tolerability outcomes.

RESULTS

The search yielded 5,675 titles and 56 studies were included. Considerable heterogeneity precluded pair-wise meta-analysis on change of pain intensity and no difference between morphine and other opioids were found for tolerability outcomes. The network meta-analysis showed no statistically significant difference in change of pain intensity between morphine and oxycodone, methadone and oxymorphone. Compared to morphine, patients using buprenorphine are more likely to discontinue treatment due to lack of effect (OR 2.32, 95% CI 1.37 to 3.95). Patients using methadone are more likely to discontinue due to adverse events (OR 3.09, 95% CI 1.14 to 8.36), whereas this risk is decreased for patients using fentanyl (OR 0.29, 95% CI 0.17 to 0.50) or buprenorphine (OR 0.30, 95% CI 0.16 to 0.53). The most important limitation of this review is that the included studies are heterogeneous with regard to study population and intervention, which may affect the pooled effect estimates. The main strength is that we only included parallel RCTs, the strongest design for intervention studies.

CONCLUSIONS

The current evidence is moderate, both in respect to the number of directly comparative studies and in the quality of reporting of these studies. No clear superiority in efficacy and tolerability of morphine over other opioids was found in pair-wise and network analyses. Based on these results, a justification for the placement of morphine as the reference standard for the treatment of severe chronic pain cannot be supported.

Current knowledge of buprenorphine and its unique pharmacological profile

Despite the increasing clinical use of transdermal buprenorphine, questions have persisted about the possibility of a ceiling effect for analgesia, its combination with other μ-opioid agonists, and the reversibility of side effects. In October 2008, a consensus group of experts met to review recent research into the pharmacology and clinical use of buprenorphine. The objective was to achieve consensus on the conclusions to be drawn from this work. It was agreed that buprenorphine clearly behaves as a full μ-opioid agonist for analgesia in clinical practice, with no ceiling effect, but that there is a ceiling effect for respiratory depression, reducing the likelihood of this potentially fatal adverse event. This is entirely consistent with receptor theory. In addition, the effects of buprenorphine can be completely reversed by naloxone. No problems are encountered when switching to and from buprenorphine and other opioids, or in combining them. Buprenorphine exhibits a pronounced antihyperalgesic effect that might indicate potential advantages in the treatment of neuropathic pain. Other beneficial properties are the compound's favorable safety profile, particularly in elderly patients and those with renal impairment, and its lack of effect on sex hormones and the immune system. The expert group agreed that these properties, as well as proven efficacy in severe pain and favorable tolerability, mean that buprenorphine can be considered a safe and effective option for treating chronic cancer and noncancer pain.

Managing severe cancer pain: the role of transdermal buprenorphine: a systematic review

Pain is a frequent and important symptom in cancer patients. Among the available strong opioids, transdermal buprenorphine has been licensed in Europe since 2002, and results from a few clinical studies suggest that it may be a good alternative to the other oral or transdermal opioids. To assess the best available evidence on its efficacy and safety, we carried out a systematic literature review with the aim of pooling relevant studies. We identified 19 eligible papers describing 12 clinical studies (6 randomized controlled trials and 6 observational prospective studies), including a total of about 5000 cancer patients. Given the poor quality of reports and the heterogeneity of methods and outcomes, pooling was not feasible as the type of data was not appropriate for combining the results statistically. A meta-analysis based on individual data is ongoing in the context of the Cochrane Collaboration. In conclusion, although the narrative appraisal of each study suggests a positive risk benefit profile, well designed and statistically powered controlled clinical trials are needed to confirm this preliminary evidence.

Transdermal buprenorphine - a critical appraisal of its role in pain management

This paper reviews the current clinical data for the role of transdermal buprenorphine (BUP TDS) in the treatment of diverse acute and chronic pain syndromes. Literature searches were carried out using PubMed (1988 to June 2009). The published findings seem to support hypotheses regarding the rather unique analgesic mechanisms of buprenorphine as compared with pure μ-opioids like morphine and fentanyl. However, the exact mechanism of this analgesic efficacy still remains largely unknown despite recent advances in preclinical pharmacological studies. Such assessments have demonstrated the sustained antihyperalgesic effect of buprenorphine in diverse animal pain models. These findings are supported in a growing number of clinical studies of oral, intrathecal, intravenous, and Bup TDS. This review paper focuses almost entirely on the clinical experience concerning the transdermal administration of buprenorphine, although preclinical aspects are also addressed in order to provide a complete picture of the unique pharmacological properties of this analgesic drug. Mounting evidence indicates the appropriateness of Bup TDS in the treatment of diverse acute and chronic pain syndromes which have been less or not responsive to other opioids. Additionally, BUP TDS seems to hold great promise for other difficult-to-treat (pain) conditions, such as patients in the intensive care setting. However, its use is somewhat tempered by the occurrence of local skin reactions which have been shown to be often therapy resistant. Further studies are certainly warranted to identify even more precisely the clinical syndromes that are most sensitive to buprenorphine treatment, and to compare buprenorphine to other opioids in head-to-head trials of acute and chronic pain conditions.

The role of transdermal buprenorphine in the treatment of cancer pain: an expert panel consensus

BACKGROUND

The semi-synthetic opioid, buprenorphine, has the general structure of morphine but differs from it in significant ways, both pharmacologically and clinically. A number of long-term studies have shown effective, long-lasting analgesia in moderate to severe cancer and non-cancer pain, including neuropathic pain, with a low incidence of constipation, nausea, dizziness and tiredness. The treatment of moderate to severe chronic pain has improved as a result of the development of new methods of administration of this substance, particularly the introduction of the transdermal drug delivery system, which offers a number of advantages over the usual oral and parenteral routes.

SCOPE

A panel of experts specialising in palliative care and pain treatment was convened in November 2007 to discuss their clinical experiences with transdermal buprenorphine and other analgesics. The aim was to provide practical guidance on the treatment of cancer pain with transdermal buprenorphine, particularly when there is a need for increasing pain relief leading to high and increasing doses. A literature search on the use of transdermal buprenorphine was carried out for the panel meeting (based on a search of PubMed to November 2007 - since updated by an additional search for the period to February 2009) and a number of case histories were presented and discussed. This commentary article presents this evidence and the consensus findings of the expert panel.

FINDINGS

The Panel reached consensus that transdermal buprenorphine was a valuable treatment for chronic cancer pain, including its neuropathic components. A number of general recommendations were made. Large-scale, randomised clinical studies are needed to provide product comparisons on the use of analgesics in the treatment of neuropathic pain although it was recognised that such studies may not be practicable. Data on the treatment of acute and chronic pain should be kept separate in general. Physicians should be made more aware of the problem of hyperalgesic effects of some opioids in long term use. Buprenorphine in contrast has been described to exert an antihyperalgesic effect. The development of analgesic tolerance with some opioids in long term use and the lack of it with buprenorphine requires further studies. The registered dose range of 35-140 microg/h was considered adequate to achieve sufficient pain relief in most patients although some members of the panel presented data showing that increases beyond this dose range provided improved pain relief if slow titration is used. However, it was generally felt that more evidence was needed before this could become generally acceptable.

CONCLUSION

The consensus was that transdermal buprenorphine has a valuable role to play in the treatment of chronic cancer pain because of its efficacy and good safety and tolerability profile, including a low risk of respiratory depression, a lack of immunosuppression and a lack of accumulation in patients with impaired renal function.