Dose-titration, multicenter study of oral transmucosal fentanyl citrate for the treatment of breakthrough pain in cancer patients using transdermal fentanyl for persistent pain

Peripherally acting opioid analgesics and peripherally-induced analgesia

The management of pain, particularly chronic pain, is still an area of medical need. In this context, opioids remain a gold standard for the treatment of pain. However, significant side effects, mainly of central origin, limit their clinical use. Here, we review recent progress to improve the therapeutic and safety profiles of opioids for pain management. Characterization of peripheral opioid-mediated pain mechanisms have been a key component of this process. Several studies identified peripheral µ, δ, and κ opioid receptors (MOR, DOR, and KOR, respectively) and nociceptin/orphanin FQ (NOP) receptors as significant players of opioid-mediated antinociception, able to achieve clinically significant effects independently of any central action. Following this, particularly from a medicinal chemistry point of view, main efforts have been directed towards the peripheralization of opioid receptor agonists with the objective of optimizing receptor activity and minimizing central exposure and the associated undesired effects. These activities have allowed the characterization of a great variety of compounds and investigational drugs that show low central nervous system (CNS) penetration (and therefore a reduced side effect profile) yet maintaining the desired opioid-related peripheral antinociceptive activity. These include highly hydrophilic/amphiphilic and massive molecules unable to easily cross lipid membranes, substrates of glycoprotein P (a extrusion pump that avoids CNS penetration), nanocarriers that release the analgesic agent at the site of inflammation and pain, and pH-sensitive opioid agonists that selectively activate at those sites (and represent a new pharmacodynamic paradigm). Hopefully, patients with pain will benefit soon from the incorporation of these new entities.

Labour analgesia; Molecular pathway and the role of nanocarriers: a systematic review

Labour is considered to be one of the most painful procedures in human experience. The most effective technique for pain relief during labour is neuraxial labour analgesia which provides analgesia without maternal or fetal sedation. Genetic predisposition may be of importance for pain perception and women experience varying degrees of pain in labour. Genetic variations in opioid receptor (OPR) genes may influence the response to epidural opioid analgesia during labour. The single-nucleotide polymorphism, A118G of the mu opioid receptor gene (oprm1), has been associated with altered pain perception. Targeted drug delivery reduces toxic side effects. Liposomes, nano-particles, nanofibres hydrogel, have been suggested to deliver anaesthetic drugs.

[Dose-finding for treatment with a transdermal fentanyl patch : Titration with oral transmucosal fentanyl citrate and morphine sulfate]

To date, no studies investigating titration with oral transmucosal fentanyl for the dose-finding of transdermal fentanyl treatment have been published. In an open randomized study 60 patients with chronic malignant (n = 39) or nonmalignant pain (n = 21), who required opioid therapy according to step three of the guidelines of the World Health Organization (WHO), were investigated. In two groups of 30 patients each titration with immediate release morphine (IRM) or oral transmucosal fentanyl citrate (OTFC) was undertaken. For measurement purposes the Brief Pain Inventory (BPI) and Minimal Documentation System (MIDOS) were used. After a 24-h titration phase, in which patients documented the intensity of pain, nausea, and tiredness, treatment with transdermal fentanyl was evaluated over a 10-day period by means of the necessary dose adaptation (responder ≤ 1 dose adaptation; conversion formula 1:1 [OTFC group] vs 100:1 [IRM group]).The pain reduction over the first 24 h (titration phase) did not differ significantly between the groups. The number of responders (17 OTFC vs. 21 IRM) over the 10-day period did not show any difference either. In both groups there was a significant reduction in pain intensity (p < 0.001). Over the course of the study, there were significantly more drop-outs because of adverse effects in the OTFC group than in the IRM group (8 vs 1, p = 0.028).Oral transmucosal fentanyl citrate can be applied for the titration of transdermal fentanyl, but it does not show any clinically relevant advantage. For example, the risk of side effects-induced drop-outs was greater in the present study. Whether the unnecessary opioid switching to treat chronic pain and breakthrough pain is advantageous with regard to minimizing conversion errors cannot be definitively answered within the scope of this study.

The use of rapid onset fentanyl in children and young people for breakthrough cancer pain

Background and aims

No published studies have looked at the dosing and use of rapid onset fentanyl preparations in children. The primary aim of this study was to assess whether there is a correlation between effective dose of rapid onset fentanyl and background oral morphine equivalent analgesia in children less than 18 years old. Secondary objectives included establishing whether there is a correlation between effective dose of rapid onset fentanyl and age and weight. Reported side effects were also reviewed.

Methods

This study is a retrospective case note review of all children less than 18 years old who received rapid onset fentanyl products in a tertiary paediatric oncology centre in England between 2010 and 2015. Correlations were analysed using Spearman’s correlation coefficient as data was non-parametric.

Results

Data on 26 children (5-17 yrs; 13-100 kg) was analysed. The most common diagnosis in children being given rapid onset fentanyl products was a solid tumour (84.6%). Eleven children used sublingual tablets, 17 used lozenges and one used a fentanyl nasal spray (three patients used two different preparations). The only significant correlation found was between dose of fentanyl lozenge and weight (r s = 0.81, p < 0.001). Very few side effects were reported with the most frequent being nausea (8%) and sleepiness (8%).

Conclusions

Fentanyl lozenges seem to be safe and well tolerated in children as young as five years old, weighing as little as 13 kg. Results suggest that children should always be started on the lowest available dose of chosen preparation and that this dose should be titrated according to response.

This study demonstrates that there is no correlation between background opioid dose and effective dose of rapid onset fentanyl in children. This mirrors findings of similar studies in adults. There was a strong correlation between effective dose of fentanyl lozenge and weight. This may be in part due to clinicians being more inclined to increase fentanyl lozenge doses as the child is in control of when they have had enough medication. In contrast, buccal tablets are absorbed quickly and the child always receives the full dose, making clinicians more reluctant to titrate the dose.

Implications

This article presents initial evidence for feasibility and tolerability of fentanyl lozenges in children as young as five years old, who are on relatively low doses of background opioids. This could be of interest to clinicians who are looking for alternatives to oral opioids to manage breakthrough pain in children with cancer.

Nanotechnology application for pain therapy

Prolonged delivery of analgesic drugs at target sites remains a critical issue for efficient pain management. The use of nano-carriers has been reported to facilitate applicable delivery of these agents to target sites with a reduced level of systemic toxicity. Different analgesics have been loaded onto various nano carriers, including those that are natural, synthetic and copolymer, for various medical applications. In this review, we will discuss the concept of nano-formulated carriers for analgesic drugs and their impacts on the field of pain management.

Rapid acting fentanyl formulations in breakthrough pain in cancer. Drug selection by means of the System of Objectified Judgement Analysis

Drug selection of rapid acting fentanyl formulations in the treatment of breakthrough pain in patients with cancer is performed by the System of Objectified Judgement Analysis method. All seven available formulations were included in the analysis. The following selection criteria were used: number of available strengths, variability in the rate of absorption, interactions, clinical efficacy, side effects, ease of administration and documentation. No direct double-blind comparative studies between two or more formulations were identified and the clinical documentation of all formulations is limited. The most distinguishing criterion was ease of use. This led to slightly higher scores for Abstral, Instanyl and PecFent than for the other formulations. The pros and cons of each formulation should be discussed with the patient, and the most suitable formulation selected for each individual patient.

Effect of Modulated Electrohyperthermia on the Pharmacokinetics of Oral Transmucosal Fentanyl Citrate in Healthy Volunteers

PURPOSE

This study aimed to determine whether changes occur in fentanyl absorption and disposition when administered in conjunction with modulated electrohyperthermia (mEHT) treatment.

METHODS

A randomized, single-dose, crossover, open-label study was used to investigate the effect of mEHT on the pharmacokinetic properties of fentanyl in 12 healthy volunteers. The 12 healthy volunteers were each administered a single dose of oral transmucosal fentanyl citrate (OTFC) or a single dose of OTFC with mEHT. mEHT was performed on the abdomen for 1 hour. Blood samples were collected for 24 hours after dosing. The temperature of the abdominal skin surface was assessed before dosing and at 10, 20, and 60 minutes after dosing.

FINDINGS

Geometric mean ratios (ratio of fentanyl with mEHT to fentanyl alone) for the C_max and AUC_0-last were 1.20 (90% CI, 1.09-1.32) and 1.15 (90% CI, 0.99-1.33), respectively. The mean temperature of the abdominal skin surface increased by approximately 4°C.

IMPLICATIONS

There was an increase in the overall exposure to the drug without implications of any clinical significance. OTFC can be administered without limitations in combination with mEHT, and it is not necessary to modify the dosing regimen. cris.nih.go,kr Identifier: KCT0001286.

Efficacy and Safety of Oral or Nasal Fentanyl for Treatment of Breakthrough Pain in Cancer Patients: A Systematic Review

Formulations of fentanyl that use buccal, sublingual, or nasal transmucosal routes of administration have been developed for the treatment of BTP in opioid-tolerant patients with cancer. The purposes of this analysis were to identify and review published data describing the efficacy and safety of different oral or nasal transmucosal fentanyl formulations for treatment of cancer-related BTP, based on a critical analysis of scientific literature. Oral transmucosal or intranasal fentanyl is an effective treatment for management of BTP episodes due to a potent analgesic effect, rapid onset of action, and sustained effect. Furthermore, it is a reasonably safe treatment, causing generally mild adverse events not leading to treatment discontinuation. Nevertheless, further progress in standardizing methodology, definitions, and criteria used both in research and in clinical practice is needed in order to generate quality information allowing a better understanding of the comparable efficacy of available formulations of fentanyl. A more rigorous assessment of long-term safety is also needed to establish a balance between benefits and risks of the available options.

Breakthrough Cancer Pain: Ten Commandments

The term "breakthrough cancer pain" (BTcP) was introduced about 25 years ago. Peaks of pain intensity reported in patients with cancer had been invariably examined in the past years, providing relevant information for a better knowledge of this phenomenon and its treatment. The aim of this critical review was to provide the golden rules, namely, the 10 commandments, for a correct diagnostic pathway of BTcP and a consequent personalized pharmacological treatment. These are as follows: 1) assessment of background analgesia, 2) drugs used for background analgesia, 3) BTcP is a frequent phenomenon, 4) characteristics of BTcP, 5) diagnosis of BTcP, 6) continuous assessment, 7) tailored pharmacological treatment of BTcP, 8) selection of BTcP medication, 9) dosing BTcP medications, and 10) education. These steps may help clinicians to recognize and treat BTcP adequately.

Fentanyl Pectin Nasal Spray Versus Oral Morphine in Doses Proportional to the Basal Opioid Regimen for the Management of Breakthrough Cancer Pain: A Comparative Study

CONTEXT

Fentanyl products have shown superiority over oral opioids for the management of breakthrough cancer pain (BTcP). However, these studies did not use an appropriate patient selection, and drugs have been compared using a different rationale.

OBJECTIVES

The aim of this randomized, crossover, controlled study was to compare the efficacy and safety of fentanyl pectin nasal spray (FPNS) and oral morphine (OM), given in doses proportional to opioid daily doses.

METHODS

Cancer patients with pain receiving ≥60 mg of OM equivalents/day and presenting with ≤3 episodes of BTcP/day were included. Patients received, in a randomized, crossover manner, FPNS or OM at doses proportional to the daily opioid regimen in four consecutive episodes of BTcP. Pain intensity was measured before (T0), 15 (T15), and 30 minutes (T30) after study drugs.

RESULTS

A total of 167 episodes were treated, 82 with FNPS and 85 with OM. A statistical difference in pain intensity between the two groups was observed at T15, but not at T30 (P = 0.018 and P = 0.204, respectively). In a greater number of episodes treated with FPNS, there was a pain decrease of ≥33% in comparison with OM after 15 and 30 minutes (76.5% vs. 32.8%, and 89% vs. 54.9%, respectively). Similar differences were found in the decrease in pain intensity of ≥50% after 15 and 30 minutes (52.3% vs. 11.4%, and 75% vs. 45.8%, respectively). The difference was highly significant at T15 (P < 0.0005). The mean (SD) pain difference at T15 of FPNS and OM were 3.24 (1.7) and 2.70 (1.2), respectively, whereas the mean (SD) SPIDs30 of FPNS and OM were 4.87 (1.7) and 4.54 (1.5), respectively. The difference was highly significant at T15 (P = 0.019). No severe adverse effects after study drug administration were observed.

CONCLUSION

When used in doses proportional to the basal opioid regimen, FPNS showed a superior analgesic effect over OM for the management of BTcP. Only minor adverse effects were found with both medications.

Prospective Observational Study of Patient-Controlled Intrathecal Analgesia: Impact on Cancer-Associated Symptoms, Breakthrough Pain Control, and Patient Satisfaction

BACKGROUND AND OBJECTIVES

Although data exist for the efficacy of intrathecal therapy (ITT), there are no prospective data on patient-controlled intrathecal analgesia (PCIA) in refractory cancer pain. This study examines the effect of PCIA on cancer symptom scores, patient satisfaction, and analgesic efficacy with an emphasis on breakthrough pain (BTP).

METHODS

Ninety-eight patients with refractory cancer pain prospectively completed questionnaires including the MD Anderson Symptom Inventory and a BTP survey before and after the implantation of an intrathecal pump.

RESULTS

Fifty-eight patients were included in the study group. Average "worst" pain scores decreased from 8.32 (SD, 1.73) pre-ITT to 4.98 (SD, 2.92) post-ITT, P < 0.001. Severe pain (numerical rating score ≥7) decreased from 84.2% to 35.2% (P < 0.001). Mean daily morphine equivalent dosing decreased from 805.3 mg/d to 128.2 mg/d, with 65.5% of patients discontinuing all nonintrathecal opioids. The mean MD Anderson Symptom Inventory symptom severity score decreased from 4.98 to 3.72 (P < 0.0001), and the symptom interference score from 6.53 to 4.37 (P < 0.001). Pain reduction was 46.8% with pre-ITT breakthrough medications and 65.2% with PCIA (P < 0.001). Median time to onset was 30 minutes with pre-ITT breakthrough medications and 10 minutes with PCIA (P < 0.001). Patient-controlled intrathecal analgesia, compared with conventional BTP medications, was "a lot better" in 60.7% and "a little better" in 28.6%. Overall pain control satisfaction was also improved, with 78.2% "a lot better" and 10.9% "I have no pain."

CONCLUSIONS

In patients with poorly controlled cancer pain, PCIA is associated with improved pain control, improved cancer-related symptoms, and high satisfaction. Compared with conventional BTP regimens, PCIA provides superior analgesia and a 3-fold faster onset of action.

Canadian recommendations for the management of breakthrough cancer pain

Breakthrough cancer pain (btcp) represents an important element in the spectrum of cancer pain management. Because most btcp episodes peak in intensity within a few minutes, speed of medication onset is crucial for proper control. In Canada, several current provincial guidelines for the management of cancer pain include a brief discussion about the treatment of btcp; however, there are no uniform national recommendations for the management of btcp. That lack, accompanied by unequal access to pain medication across the country, contributes to both regional and provincial variability in the management of btcp. Currently, immediate-release oral opioids are the treatment of choice for btcp. This approach might not always offer optimal speed for onset of action and duration to match the rapid nature of an episode of btcp. Novel transmucosal fentanyl formulations might be more appropriate for some types of btcp, but limited access to such drugs hinders their use. In addition, the recognition of btcp and its proper assessment, which are crucial steps toward appropriate treatment selection, remain challenging for many health care professionals. To facilitate appropriate management of btcp, a group of prominent Canadian specialists in palliative care, oncology, and anesthesiology convened to develop a set of recommendations and suggestions to assist Canadian health care providers in the treatment of btcp and the alleviation of the suffering and discomfort experienced by adult cancer patients.

WITHDRAWN: Opioids for the management of breakthrough pain in cancer patients

At August 2015, this review has been withdrawn. It is correct at the date of publication, and previous versions can be accessed in the ‘Other versions’ tab on the Cochrane Library. The Cochrane Editorial Unit (CEU) agreed with the authors of the feedback that the review was misleading, and because the original author team was unavailable to update the review, the CEU advised that it should be withdrawn. See below for full details. PaPaS is seeking a new author team to develop a new review which will serve to update the original.

Feedback 1, received 15 February 2015

Dr Vicente Ruiz Garcia
 vicenteruizgarcia@gmail.com

With colleagues Xavier Bonfill Cosp, Eduardo Lopez Briz, Rafa Carbonell, Jose Luis Gonzalvez Perales, Sylvia Bort Martí, and Marta Roque Figuls.

Comment: Dear editor:

We have read the update of Zeppetella and Davies about management of breakthrough pain in cancer patients (1). We think that this review is very important to help clinicians and patients to decide whether the new treatments for the breakthrough pain in cancer could be a useful alternative to morphine.

In this update, some comments that we made to the previous review (the letter was not published) (2) were considered by the authors; in particular, not pooling the results obtained for oral transmucosal fentanyl citrate (OTFC) versus placebo, with those of OTFC versus morphine, and those of two trials that were titration of doses of fentanyl. However, we do not agree with the authors’ results when they state: “When compared with placebo or oral morphine, participants gave lower pain intensity and higher pain relief scores for transmucosal fentanyl formulations at all time points”. First, the outcomes at 15 min (the most important to obtain a quick relief of pain), Pain intensity Difference (Comparison 2. Transmucosal opioid versus oral morphine) and Comparison 4. OTFC versus intravenous morphine), failed to show statistically significant differences with oral morphine (mean difference 0.37 CI 95% 0.00‐0.73) and with morphine iv (mean difference 0.80 CI 95% 0.00‐1,60). In any case the results had no clinical relevance. Moreover the authors state “at all time points”, whereas they do not provide any data for longer times (i.e. 30, 45, 60 min). In addition, authors state “transmucosal fentanyl citrate are safe (..) (compared with both placebo and morphine) in relieving breakthrough pain”. Surprisingly no analysis of adverse events have been done that were only described in each study. Seven out 15 were crossover trials and it was impossible to draw conclusions about it.

As reviewers we know that multiple comparisons could be made, but the most clinical interesting comparison is the gold standard, morphine.

The review only shows in SOF, comparisons of fentanyl with placebo and concludes, that it is effective. Surprisingly, there is no mention of morphine comparison, which we consider a key point, because no patient will take placebo if he has a breakthrough pain, but morphine for obvious reasons.

In our opinion, traversing the authors’ conclusions, this review did not show that the use of oral and nasal transmucosal fentanyl is an effective alternative to morphine for patients with breakthrough cancer pain.

Reply

The authors of the review were contacted but chose not to provide a response to the feedback.

Contributors

Kate Seers, PaPaS Feedback Editor, and Anna Hobson, PaPaS Managing Editor.

Additional feedback 2, received May 2015

On 15 February 2015, Dr Vicente Ruiz Garcia (University Hospital La Fe, Spain), and his colleagues Xavier Bonfill Cosp, Eduardo Lopez Briz, Rafa Carbonell, Jose Luis Gonzalvez Perales, Sylvia Bort Martí, and Marta Roque Figuls submitted feedback via the Cochrane Library. The main complaint is available above.

On 23 February, 16 March and 15 April, Kate Seers (Feedback Editor, PaPaS) contacted the authors and invited them to respond. On 21 March, John Zeppetella (lead author) declined to provide a formal response. No response was received from Andrew Davies (second author).

On 31 March, PaPaS sought advice from the Cochrane Editorial Unit (CEU) on how to manage the issue; advised to publish without a response, depending on nature of feedback.

On 11 May 2015, review re‐published with feedback incorporated.

On 20 May 2015, Marta Roqué Figuls (Statistician, Iberoamerican Cochrane Centre) wrote to the CEU repeating the initial claim. They did not agree with the approach decided upon by the Co‐Ed, which was supported by the EiC. They stated “The CCIb assessment is that the review presents methodological shortcomings, and the conclusions are skewed in favor of fentanyl. Consequently, we support Vicente and colleagues’ petition to re‐assess the publication status of the review.”

Reply

On 9 June, Christopher Eccleston (Co‐ordinating Editor, PaPaS) advised that the review remain unchanged until it was ready for updating in September 2015.

On 25 June 2015 David Tovey (Editor in Chief, Cochrane) responded to say “We have now had a chance to appraise this review and also obtain a report from our screening team… In summary we agree with almost all of the criticisms made of the review, and are concerned that the flaws may mean that the findings are misleading as currently presented. We note that the authors have declined to respond to the useful comments provided by Vicente. Having considered this and discussed it internally, we agree with our colleagues at the IbCC that the review should be withdrawn temporarily until the errors have been fixed and the review updated. We would like to re‐screen the review before any update or amendment is published.”

On 2 July and 23 July, Anna Hobson (Managing Editor, PaPaS) again invited the authors to respond to the initial feedback and subsequent reviews by 23 July. No response was forthcoming.

At August 2015, the review was withdrawn.

Contributors

Kate Seers (Feedback Editor, PaPaS), Cochrane Editorial Unit (CEU), Christopher Eccleston (Co‐ordinating Editor, PaPaS), David Tovey (Editor in Chief, Cochrane), Anna Hobson (Managing Editor, PaPaS).

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

Patient Satisfaction with Fentanyl Sublingual Spray in Opioid-Tolerant Patients with Breakthrough Cancer Pain

OBJECTIVES

Breakthrough cancer pain (BTCP) is associated with decreased satisfaction with around-the-clock opioid therapy. This analysis examined patient satisfaction with fentanyl sublingual spray for BTCP during the open-label titration period of a randomized, placebo-controlled study.

METHODS

Opioid-tolerant patients with 1 to 4 daily BTCP episodes were included. During a 26-day, open-label titration phase, a successful dose (100 to 1600 mcg) of fentanyl sublingual spray was established that provided effective analgesia for 2 consecutive BTCP episodes with tolerable side effects. The Treatment Satisfaction Questionnaire for Medication (TSQM) was administered at baseline to assess satisfaction with previous BTCP medication and at the end of the titration to assess satisfaction with fentanyl sublingual spray.

RESULTS

Of 130 enrolled patients, 115 (88.5%) had a TSQM measure at baseline and at the end of their titration period. Scores on all 4 TSQM domains increased from baseline to end of the titration, with mean (standard error [SE]) improvements of 22.3 (2.3) for effectiveness, 7.7 (3.2) for side effects, 6.8 (2.2) for convenience, and 12.9 (2.8) for global satisfaction (P < 0.05 for all). Satisfaction with symptom relief (26.1% to 77.4%) and onset of action (21.7% to 82.6%) also improved from baseline to end of titration. At least one adverse event (AE) was reported by 78 patients (60.0%). The most common AEs considered possibly or probably related to study medication were dizziness, somnolence, and nausea (n = 10 [7.7%] each).

DISCUSSION

These data indicate markedly improved satisfaction among patients receiving fentanyl sublingual spray relative to previous BTCP medications.

A randomized, double-blind, placebo-controlled study of fentanyl buccal tablets for breakthrough pain: efficacy and safety in Japanese cancer patients

CONTEXT

Rapid-onset opioids for treating breakthrough pain (BTP) in patients with cancer are needed in the Japanese care setting.

OBJECTIVES

To examine the efficacy and safety of fentanyl buccal tablets (FBTs) for treating BTP in Japanese cancer patients.

METHODS

This was a randomized, double-blinded, placebo-controlled study. In subjects receiving around-the-clock (ATC) opioids at doses of 30 mg or more to less than 60 mg or 60-1000 mg of oral morphine equivalents (low and high ATC groups), dose titration was started from 50 to 100 μg FBT, respectively. Subjects whose effective dose was identified were randomly allocated to a prearranged administration order of nine tablets (six FBTs and three placebos), one tablet each for nine episodes of BTP (double blinded). Efficacy and safety of FBT were assessed for patients overall, and also for the low and high ATC groups.

RESULTS

A significant difference was observed between FBT and placebo for the primary endpoint of pain intensity difference at 30 minutes. The analgesic onset of FBT was observed from 15 minutes in several secondary variables (e.g., pain relief). Adverse events were somnolence and other events associated with opioids were mostly mild or moderate. Of the low and high ATC group subjects, an effective FBT dose was identified in 72.2% and 73.1%, respectively.

CONCLUSION

The safety of FBT and its analgesic effect on BTP were confirmed in Japanese cancer patients receiving opioids. Our findings suggest that analgesic onset may occur from 15 minutes after FBT, and that FBT can be administered to patients with low doses of ATC opioids.

How are palliative care cancer populations characterized in randomized controlled trials? A literature review

CONTEXT

The difficulties in defining a palliative care patient accentuate the need to provide stringent descriptions of the patient population in palliative care research.

OBJECTIVES

To conduct a systematic literature review with the aim of identifying which key variables have been used to describe adult palliative care cancer populations in randomized controlled trials (RCTs).

METHODS

The data sources used were MEDLINE (1950 to January 25, 2010) and Embase (1980 to January 25, 2010), limited to RCTs in adult cancer patients with incurable disease. Forty-three variables were systematically extracted from the eligible articles.

RESULTS

The review includes 336 articles reporting RCTs in palliative care cancer patients. Age (98%), gender (90%), cancer diagnosis (89%), performance status (45%), and survival (45%) were the most frequently reported variables. A large number of other variables were much less frequently reported.

CONCLUSION

A substantial variation exists in how palliative care cancer populations are described in RCTs. Few variables are consistently registered and reported. There is a clear need to standardize the reporting. The results from this work will serve as the basis for an international Delphi process with the aim of reaching consensus on a minimum set of descriptors to characterize a palliative care cancer population.

A network meta-analysis of the efficacy of opioid analgesics for the management of breakthrough cancer pain episodes

CONTEXT

With many medications available for the management of breakthrough cancer pain (BTCP), physicians may require additional guidance in selecting an appropriate medication to suit an individual patient's needs.

OBJECTIVES

To identify all the evidence and assess the relative clinical value of currently approved BTCP medications.

METHODS

Following a systematic literature search (2007-2010), the results of 10 randomized controlled trials investigating the effects of BTCP medications (intranasal fentanyl spray [INFS], fentanyl pectin nasal spray, fentanyl sublingual tablets, fentanyl buccal soluble film, fentanyl buccal tablets, oral transmucosal fentanyl citrate, and morphine sulfate immediate release) were synthesized using a network meta-analysis. The main outcome was pain intensity difference (PID) relative to placebo up to 60 minutes after the intake of medication.

RESULTS

INFS, fentanyl pectin nasal spray, fentanyl buccal tablet, and oral transmucosal fentanyl citrate showed greater PIDs relative to placebo than other BTCP medications 15 minutes after intake. All other medications showed greater PIDs relative to placebo at 30 minutes, except morphine sulfate immediate release, which did not show efficacy over placebo until 45 minutes. Only INFS produced clinically meaningful pain relief (absolute PID ≥2) at 15 minutes.

CONCLUSION

From current evidence, although all BTCP medications provided pain relief within the time frames assessed, transmucosal fentanyl medications achieved a greater level of pain relief in a shorter time frame than placebo or oral morphine.

Opioids for the management of breakthrough pain in cancer patients

BACKGROUND

This review is an update of a previously published review in the Cochrane Database of Systematic Reviews (Issue 1, 2006). Breakthrough pain is a transient exacerbation of pain that occurs either spontaneously or in relation to a specific predictable or unpredictable trigger despite relative stable and adequately controlled background pain. Breakthrough pain usually related to background pain and is typically of rapid onset, severe in intensity and generally self limiting with a mean duration of 30 minutes. Breakthrough pain has traditionally been managed by the administration of supplemental oral analgesia (rescue medication) at a dose proportional to the total around-the-clock (ATC) opioid dose.

OBJECTIVES

To determine the efficacy of opioid analgesics given by any route, used for the management of breakthrough pain in patients with cancer, and to identify and quantify, if data permitted, any adverse effects of this treatment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and trial registries in January 2005 for the original review, and again on 6 February 2013 for this update.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of opioids used as rescue medication against active or placebo comparator in patients with cancer pain. Outcome measures sought were reduction in pain intensity measured by an appropriate scale, adverse effects, attrition, patient satisfaction and quality of life. We applied no language restrictions.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected and examined eligible studies. We retrieved full text if any uncertainty about eligibility remained. We screened non-English texts. We conducted quality assessment and data extraction using standardised data forms. We compared drug and placebo dose, titration, route and formulation and recorded details of all outcome measures (if available).

MAIN RESULTS

The original review included four studies (393 participants), all concerned with the use of oral transmucosal fentanyl citrate (OTFC) in the management of breakthrough pain. Two studies examined the titration of OTFC, one study compared OTFC versus normal-release morphine and one study compared OTFC versus placebo.Fifteen studies (1699 participants) met the inclusion criteria for this update. All studies reported on the utility of seven different transmucosal fentanyl formulations, five of which were administered orally and two nasally. Eight studies compared the transmucosal fentanyl formulations versus placebo, four studies compared them with another opioid, one study was a comparison of different doses of the same formulation and two were randomised titration studies. Oral and nasal transmucosal fentanyl formulations were an effective treatment for breakthrough pain. When compared with placebo or oral morphine, participants gave lower pain intensity and higher pain relief scores for transmucosal fentanyl formulations at all time points. Global assessment scores also favoured transmucosal fentanyl preparations. One study compared intravenous with the transmucosal route and both were effective.

AUTHORS' CONCLUSIONS

Oral and nasal transmucosal fentanyl is an effective treatment in the management of breakthrough pain. The RCT literature for the management of breakthrough pain is relatively small. Given the importance of this subject, more trials, including head-to-head comparisons of the available transmucosal fentanyl formulations are required.

Single-dose pharmacokinetics of fentanyl sublingual spray and oral transmucosal fentanyl citrate in healthy volunteers: a randomized crossover study

BACKGROUND

Fentanyl sublingual spray (FSS) is a novel fentanyl formulation recently developed for the treatment of breakthrough cancer pain, which is characterized by a fast onset and a relatively short duration.

OBJECTIVE

To compare rate of absorption and systemic bioavailability between FSS and oral transmucosal fentanyl citrate (OTFC) in healthy volunteers.

METHODS

This randomized 3-way crossover study involved 29 healthy volunteers (25 men and 4 women; mean age, 35 years) who received single doses of FSS (400 μg), OTFC (400 μg), and intravenous fentanyl citrate (100 μg) separated by washout periods of ≥7 days. Oral naltrexone was given to minimize potential adverse effects of fentanyl. Plasma fentanyl concentrations were measured for 36 hours after each dose for the calculation of pharmacokinetic parameters.

RESULTS

Mean Cmax values of fentanyl were higher with FSS versus OTFC (0.81 ng/mL vs 0.61 ng/mL) and were attained more quickly; the median Tmax was 1.5 hours with FSS and 2.0 hours with OTFC (P < 0.05). Furthermore, potentially effective fentanyl concentrations were achieved more quickly with FSS than with OTFC. Five and 10 minutes after administration, mean plasma concentrations were 19.0% and 53.7% of Cmax with FSS, respectively, compared with levels below the lower limit of assay quantification and 6.1%, respectively, with OTFC. Plasma concentrations of fentanyl at 10 minutes with FSS were equivalent to those with OTFC at 60 minutes. The Cmax and AUCs were approximately 33% to 36% greater with FSS than with OTFC, and the 90% CIs of the geometric mean ratios for each parameter fell outside the bioequivalence range of 80% to 125%. Systemic bioavailability was also greater with FSS than with OTFC (approximately 76% vs 51%). All 3 fentanyl treatments were well tolerated. All reported adverse events were mild and consistent with those previously reported in healthy volunteers receiving transmucosal fentanyl with naltrexone, and none occurred in >2 participants during any treatment period.

CONCLUSIONS

Absorption of fentanyl in this study was faster and bioavailability was greater with FSS than with OTFC. The pharmacokinetic profile of the sublingual spray closely matches the duration of onset to pain intensity in a breakthrough cancer pain episode. These findings suggest that FSS is appropriate for the treatment of breakthrough cancer pain. ClinicalTrials.gov identifier: NCT01780233.

Fentanyl for the treatment of tumor-related breakthrough pain

BACKGROUND

Breakthrough cancer pain (BTCP) is common among cancer patients and markedly lowers their quality of life. The treatment for BTCP episodes that is recommended in current guidelines involves extended-release formulations in combination with rapid-onset and short-acting opioids. In the past few years, several new preparations of fentanyl, an opioid with a very rapid onset, have been approved for this indication. Treating physicians need to be aware of the clinical differences between the newer fentanyl preparations and immediate-release opioids.

METHODS

We searched the PubMed and Embase databases for randomized controlled trials (RCTs) of fentanyl for buccal, sublingual or intranasal administration in comparison with other opioids or a different fentanyl preparation for the treatment of BTCP.

RESULTS

In 6 trials of buccal, sublingual or intranasal fentanyl versus oral immediate-release opioids for the treatment of BTCP episodes, the use of fentanyl was associated with significantly less intense pain. In particular, fentanyl more often lowered the intensity of pain by at least 33% (range between studies: 13% to 57%) or by at least 50% (range between studies: 9% to 38%) within 15 minutes. Please change to "versus" if you agree.] Dose titration should begin at the lowest dose. When one fentanyl preparation is exchanged for another, the effective dose will probably differ.

CONCLUSION

The newer fentanyl preparations extend the treatment options for BTCP. They relieve pain within a short time better than conventional, immediate-release oral opioids do and may therefore be very helpful for patients with suddenly arising, intense, and short-lasting BTCP episodes. Further comparative trials are urgently needed.

Considerations in selecting rapid-onset opioids for the management of breakthrough pain

Breakthrough pain (BTP) is a transitory pain that occurs despite the use of long-term, around-the-clock analgesia. It is highly prevalent in certain populations and places a significant burden on patients, their families, caregivers, and health-care systems. Despite its prevalence and impact, BTP is sometimes unrecognized and often undertreated. Various formulations of fentanyl – a rapid-onset opioid with short duration of action – are available for the management of BTP. The efficacy of formulations using transmucosal, transbuccal, sublingual, and intranasal administration routes has been demonstrated for BTP treatment in clinical trials. However, a lack of head-to-head trials evaluating their relative efficacy makes it challenging for physicians to reach informed decisions on the most efficacious intervention for individual patients. In the absence of clear data on the relative efficacy of fentanyl formulations, prescribing decisions need to be based on physician understanding and experience and product cost and availability, taking into account the individual patient’s needs, the ability of the patient or caregivers to administer medication, and the patient’s wishes. This review evaluates current pharmacologic methods of alleviating BTP and discusses factors that should be considered when selecting the most appropriate formulation for individual patients. With the range of fentanyl formulations available, it is now possible to successfully address BTP in the majority of patients.

Grading clinical guidelines for the use of transmucosal immediate-release fentanyl products in breakthrough pain

Pain is a complex symptom that is commonly feared in palliative care owing to its significant effects on patients' quality of life (QoL), and is directly associated with morbidity. More specifically, the management of breakthrough pain (BTP) is particularly important. Opioids play a major part in the management of BTP, and the various transmucosal immediate-release fentanyl (TIRF) products are a common treatment choice. This paper considers the strength of the evidence underlying recommendations regarding the use of TIRF. Failure to consider the quality of evidence in practice can lead to misguided recommendations. Guidelines should therefore be used to inform clinicians of the quality of the underlying evidence and whether recommendations are strong or weak. The GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach is increasingly being adopted worldwide as it provides a system for rating quality of evidence and strength of recommendations that is clear, comprehensive, transparent, and practical. This paper adopts the GRADE approach to assess the strength of recommendations made in a 2011 review by Zeppetella in order to develop guidelines for the use of TIRF. The recommendations include that TIRF products can be considered for first-line treatment and that they should be individualised to patients who are on a background opioid.

Fentanyl (transmucosal)

Therapeutic Reviews aim to provide essential independent information for health professionals about drugs used in palliative and hospice care. Additional content is available on www.palliativedrugs.com. Country-specific books (Hospice and Palliative Care Formulary USA, and Palliative Care Formulary, British and Canadian editions) are also available and can be ordered from www.palliativedrugs.com. The series editors welcome feedback on the articles (hq@palliativedrugs.com).

A comprehensive review of rapid-onset opioids for breakthrough pain

Breakthrough pain (BTP) is a transitory pain (reaching maximum severity in ~15 minutes and lasting ~60 minutes in patients with cancer) that occurs despite the management of chronic pain with long-term around-the-clock analgesia. BTP occurs in 33-65% of patients with chronic cancer pain and in ~70% of patients with chronic noncancer pain. BTP has historically been managed with short-acting opioids; however, these medications have a pharmacokinetic profile that does not correlate with the sudden onset and short time to maximum severity of BTP. Interest in rapid-onset opioids to relieve BTP has therefore been growing. This comprehensive review aims to summarize the currently available clinical data for the approved rapid-onset opioids, which comprise different formulations of fentanyl, a μ-opioid receptor agonist with anaesthetic and analgesic properties. Administration routes for fentanyl in the management of BTP currently include the transmucosal and intranasal routes; an intrapulmonary formulation is also in development. The findings of this review suggest that the efficacy and safety of the approved rapid-onset opioids are comparable.

A phase I pharmacokinetic and bioavailability study of a sublingual fentanyl wafer in healthy volunteers

BACKGROUND

The sublingual administration of opioids is a simple and noninvasive method that provides rapid analgesia. In this phase I study we investigated the pharmacokinetics and bioavailability of a fentanyl wafer in healthy volunteers. The principal study objective was to investigate the pharmacokinetic profile of a new sublingual fentanyl wafer and to establish its absolute bioavailability.

METHODS

Twenty-four healthy volunteers, mean age 23 years, were randomly assigned to receive the equivalent of fentanyl 100 μg by both the sublingual and IV routes. Blood samples were collected in sterile polypropylene tubes for 24 hours after each fentanyl administration. The pharmacokinetic parameters were determined by model-independent pharmacokinetic analyses of the plasma fentanyl concentration-time profiles.

RESULTS

The mean absolute bioavailability of the sublingual fentanyl wafer was 78.9% (90% confidence interval [CI] 51.1% to 121.7%). The first detectable plasma fentanyl concentration time ranged from 2 to 10 minutes in all volunteers, and the mean (±SD) time to peak plasma concentration at 0.91 (±0.73) hours after administration.

CONCLUSION

Sublingual administration of fentanyl as a wafer product resulted in rapidly detectable plasma fentanyl concentrations. The absolute bioavailability of 78.9% indicated a high systemic availability of fentanyl and suggests that further development of this wafer is justified.

Efficacy and safety of fentanyl sublingual spray for the treatment of breakthrough cancer pain: a randomized, double-blind, placebo-controlled study

BACKGROUND AND OBJECTIVES

A number of transmucosal fentanyl formulations have been developed for the management of breakthrough cancer pain (BTCP). Sublingual delivery of fentanyl, formulated as fentanyl sublingual spray, offers the potential for more rapid and greater absorption of fentanyl and associated onset of analgesic effect compared with other formulations. The objective of this study was to assess the efficacy and safety of fentanyl sublingual spray for the treatment of BTCP.

RESEARCH DESIGN AND METHODS

This was a randomized, double-blind, placebo-controlled phase III trial conducted in opioid-tolerant patients with BTCP. An open-label titration period was followed by a double-blind treatment period during which patients received fentanyl sublingual spray (100-1600 mcg) or placebo.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT00538850.

MAIN OUTCOME MEASURES

The primary efficacy measure was summed pain intensity difference at 30 minutes (SPID(30)). Secondary efficacy measures included total pain relief at 30 minutes (TOTPAR(30)) and patient global evaluation of study medication at 30 minutes. Efficacy measures were also assessed at various time points from 5-60 minutes postdose. Adverse events were monitored throughout the study.

RESULTS

A total of 130 patients were treated during the titration period, of whom 98 (75.4%) entered the double-blind period. Relative to placebo, fentanyl sublingual spray significantly improved mean SPID scores from 5 minutes (p = 0.0219) through 60 minutes (p < 0.0001), including the primary endpoint at 30 minutes (p < 0.0001). Fentanyl sublingual spray produced significantly greater pain relief (expressed in terms of TOTPAR) from 5 through 60 minutes (p < 0.0001), and significantly greater global evaluation of treatment effectiveness (p < 0.0001), compared with placebo. During double-blind treatment, the most frequently reported adverse events were nausea (7.1%), hyperhidrosis (5.1%), and peripheral edema (5.1%). Serious adverse events occurred in seven patients (5.4%) during titration and six (6.1%) during double-blind treatment; none were considered related to treatment.

CONCLUSIONS

These findings indicate that treatment with fentanyl sublingual spray results in effective relief of BTCP, with a rapid onset of action, and is well tolerated.

Oral trasmucosal fentanyl citrate for breakthrough pain treatment in cancer patients

INTRODUCTION

Breakthrough cancer pain has been defined as a transitory increase in pain intensity that occurs either spontaneously or in relation to a specific predictable or unpredictable trigger, despite relatively stable and adequately controlled background pain. The availability of supplemental doses of oral opioids, in addition to the continuous analgesic medication, is the main treatment suggested to manage pain flares.

AREAS COVERED

Oral transmucosal fentanyl citrate (OTFC) is the first product of a new generation of delivery systems, named rapid-onset opioids (ROOs), characterized by rapidity of effect and the short duration of analgesia. Controlled studies and long-term experience have shown that OTFC is an effective treatment for breakthrough pain management and its use should be considered in any patient experiencing breakthrough pain related to cancer.

EXPERT OPINION

The onset of action of OTFC - demonstrated to start within 15 min - and the short time to maximum concentration make it a useful indication for breakthrough pain; dose titration is commonly recommended. However, it is likely that patients receiving high doses of opioids for background analgesia will not be candidates for titration with minimal initial doses of OTFC, as they are opioid tolerant and the process would be time consuming.

Fentanyl for breakthrough pain: a systematic review

The purpose of this article is to systematically review the use of fentanyl as an analgesic for breakthrough pain. This article found that the oral transmucosal fentanyl (OTFC) had a quicker onset to analgesia than oral immediate-release opioids. Intranasal fentanyl (INFS) had a quicker onset to analgesia than buccal tablets, which in turn had a quicker onset to analgesia than OTFC. Patient acceptance and global rating of efficacy were greater for INFS than for buccal fentanyl. OTFC and INFS have been used effectively to reduce acute pain in children who are opioid-naive. Abuse and addiction to OTFC, fentanyl buccal tablets and INFS was low, owing to patient selection.

Patient-controlled intrathecal analgesia for the management of breakthrough cancer pain: a retrospective review and commentary

OBJECTIVE

  Intrathecal therapy (ITT) via an implanted pump has become an accepted practice for the treatment of refractory cancer pain by infusing opioids and adjuncts directly to the neuraxis. Until recently, only a programmed basal rate of infusion could be delivered, and therefore, breakthrough pain required ongoing use of oral or transmucosal opioids. Recently, an implanted pump manufacturer has introduced a handheld device to bolus additional medication for breakthrough pain. We hypothesize that patient-controlled intrathecal analgesia (PCIA) for the treatment of breakthrough cancer pain reduces the need for breakthrough opioids and improves the patient perception of pain.

METHODS

  A retrospective chart review was done on all patients who underwent ITT for cancer pain between January 2009 and February 2011. Clinical outcomes of interest were reduction in nonintrathecal opioid use and reduction in numerical rating score (NRS) for pain. The data was collected prior to ITT and at a 4-6 week postimplant visit.

RESULTS

  After initiation of ITT with PCIA, 50% of patients had discontinued all nonintrathecal opioids at follow-up, and 46% of the patients on breakthrough medications no longer required their use. At follow-up, there was a significant reduction in total nonintrathecal opioid use, with an average of 796 mg pre-ITT vs 64 mg post-ITT of daily oral morphine equivalent dosing (P = <0.001). There was a significant difference between mean NRS pain score at follow-up-6.5 vs 3.1 pre-ITT (P<0.001). 65% of patients reported their pain as severe (NRS of 7 or greater) prior to ITT; this decreased to 3% at follow-up.

CONCLUSIONS

  In patients with refractory cancer pain, intrathecal drug therapy with PCIA is associated with improved pain reporting, reduced nonintrathecal around-the-clock, and breakthrough opioid requirements.

Opioids for the management of breakthrough cancer pain in adults: a systematic review undertaken as part of an EPCRC opioid guidelines project

The usual management of cancer related breakthrough pain is with supplemental doses of analgesics (commonly opioids) at a dose proportional to the total around-the-clock opioid dose. The aim of this review, undertaken as part of a European Palliative Care Research Collaborative (EPCRC) project, to update the EAPC guidelines on opioid analgesics in cancer pain was to determine the evidence for the utility of opioids in the management of breakthrough pain in patients with cancer. Randomized controlled trials of opioids used as rescue medication were identified using electronic search strategies. Outcome measures sought were reduction in pain intensity measured by an appropriate scale, adverse effects, attrition, and patient satisfaction. The date of the final search was 31 July 2009. Eight studies (790 patients) met the inclusion criteria. Most studies investigated rescue medication delivery via the buccal or nasal transmucosal routes. Intravenous morphine has been compared with the transmucosal route and the two found to be effective. The oral route has not been formally tested although found to be an inferior comparator in one study. Most studies showed no meaningful relationship between the effective dose of transmucosal opioid and the around-the-clock scheduled medication or the previous rescue medication, although one study found a fixed proportion of either intravenous morphine or transmucosal fentanyl to be efficacious.

Integrated strategies for the successful management of breakthrough cancer pain

PURPOSE OF REVIEW

To highlight the significant impact breakthrough cancer pain (BTcP) can have on patients' quality of life and to discuss potential management strategies that could improve pain control in clinical practice as well as effective strategies to manage risk.

RECENT FINDINGS

BTcP can place a significant physical, psychological and economic burden on patients. Despite advances in the management of cancer pain, through the application of modern, evidence-based, multimodality management and the availability of new treatment options, recent European surveys have indicated that the diagnosis and treatment of BTcP is still suboptimal. A general lack of consensus on its definition alongside poor recognition and inadequate assessment may often lead to undertreatment and poor patient outcomes. Fentanyl preparations that have been developed and licensed specifically for the treatment of BTcP have been shown to work more rapidly and be preferred by patients to traditional rescue medication, such as normal-release oral opioids.

SUMMARY

Optimizing the management of BTcP requires an integrated approach, including independent assessment and better use of available treatments while taking into consideration risk management strategies, which will ultimately lead to improved outcomes and quality of life for patients.

Treatment of breakthrough pain with fentanyl buccal tablet in opioid-tolerant patients with chronic pain: appropriate patient selection and management

BACKGROUND

Opioids can be a safe and effective option for carefully selected patients with a structured treatment program that includes consistent monitoring. However, the benefits and risks of opioid therapy for patients with chronic pain, and society as a whole, have been sharply debated. A key component of this debate has involved the administration of rapid-onset opioids for the management of breakthrough pain.

OBJECTIVE

Review key aspects of breakthrough pain management with fentanyl buccal tablet, with a focus on minimizing risk to optimize therapeutic outcomes. Recommendations that apply broadly to all rapid-onset opioids are also discussed.

DESIGN

Available fentanyl buccal tablet clinical and post-marketing data were reviewed.

RESULTS

Like other schedule II controlled substances, and because fentanyl buccal tablet is a highly potent opioid, its use is associated with risk of overdose, misuse, and diversion. As with all rapid-onset opioids, particular attention to patient selection and risk assessment is warranted. The inclusion and exclusion criteria in fentanyl buccal tablet clinical studies represent patient selection standards that should be translated to clinical practice, most importantly, that patients are opioid-tolerant before fentanyl buccal tablet initiation. Titration of fentanyl buccal tablet from a low starting dose to a successful dose allows the safe identification of a dose that provides the greatest pain relief without unacceptable adverse events. After initiating fentanyl buccal tablet therapy, all patients should continue to be regularly monitored for response, including analgesia, functioning, tolerability, and aberrant behavior.

CONCLUSIONS

Fentanyl buccal tablet can be an effective and generally safe treatment for breakthrough pain when appropriate patient selection, administration, dosing, and monitoring are applied.

A novel 12-week study, with three randomized, double-blind placebo-controlled periods to evaluate fentanyl buccal tablets for the relief of breakthrough pain in opioid-tolerant patients with noncancer-related chronic pain

OBJECTIVE

To evaluate the time of onset, overall efficacy, and safety of fentanyl buccal tablet (FBT) for noncancer-related breakthrough pain (BTP) in opioid-tolerant adults over 12 weeks.

DESIGN

A novel 12-week study that mimicked clinical practice with dose titration to effective dose, open-label treatment, and three randomized, double-blind, placebo-controlled, multiple-crossover periods at weeks 4, 8, and 12. For each double-blind period, study patients received nine doses (FBT = 6, placebo = 3) in a randomized sequence.

SETTING

Twenty-one study centers in the United States.

POPULATION

Opioid-tolerant adults with noncancer-related chronic pain and BTP.

OUTCOME MEASURES

The primary outcome was the sum of the pain intensity differences (PID) 5-60 minutes post dose (SPID₆₀) during the final double-blind period. Secondary outcomes included pain relief (PR), meaningful PR, and proportion of episodes with a PID of ≥33% and ≥50%.

RESULTS

Of 148 patients who entered the titration phase, 105 (71%) achieved a successful dose and 81 (55%) participated in all three assessment periods in the study. The final RCT assessment period results demonstrated continued efficacy of FBT vs placebo (P < 0.05) for SPID₆₀ (mean [SD]: 7.7 [6.2] vs 4.6 [4.7]). The average onset of PR began at 5 minutes, with meaningful PR by ≤10 minutes. The proportion of episodes with ≥33% improvement in PI was 7% with FBT vs 3% with placebo at 5 minutes and with ≥50% was 17% vs 10% at 15 minutes. All periods showed similar results. Adverse events and patient discontinuations were generally typical of clinical opioid use.

CONCLUSIONS

FBT showed continued clinically important analgesic effects and was generally well tolerated over 12 weeks of treatment.

Characterization of cancer-induced bone pain: an exploratory study

PURPOSE

Cancer-induced bone pain (CIBP) is the commonest cause of pain in patients with cancer. Its association with increased morbidity combined with limitations of currently available therapies makes it a clinical challenge. Clinical characterization of this complex pain syndrome is essential in underpinning clinical management and informing future research. The aim of this exploratory study was to characterise CIBP using self-rating scales.

PATIENTS AND METHODS

A cross-sectional survey of patients with CIBP was carried out in a regional oncology centre. Patients described their pain over the preceding 24 h using the McGill Pain Questionnaire, Brief Pain Inventory (BPI), and a breakthrough pain questionnaire. Multiple linear regression analyses were conducted.

RESULTS

Fifty-five patients were recruited. Annoying, gnawing, aching, and nagging were the most commonly used words to describe CIBP. From the BPI, median average pain was 4/10 and worst pain was 7/10 on a 0-10 Numerical Rating Scale. The worst pain score correlated more strongly with BPI interference score (p=0.001). Forty-one patients had breakthrough pain. Patients with breakthrough pain had higher total BPI interference scores than those with no breakthrough pain; median (IQR); 35.0 (2.5-44.7) vs. 18.5 (5.5-26.7), p<0.01. Of the patients, 20/41 (48%) had breakthrough pain of rapid onset (less than 5 min) and short duration (less than 15 min).

CONCLUSION

In CIBP, worst pain most accurately reflects the characteristics of pain flares and functional impairment. Breakthrough pain is often unpredictable, sudden onset and short duration. Further characterization studies of CIBP in the broader cancer population are needed.