Dynamics of breakthrough pain vs. pharmacokinetics of oral morphine: implications for management

Breakthrough pain and rapid-onset opioids in patients with cancer pain: a narrative review

Breakthrough pain is transitory pain that occurs despite the use of opioids for background pain control. Breakthrough pain occurs in 40% to 80% of patients with cancer pain. Despite effective analgesic therapy, patients and their caregivers often feel that their pain is not sufficiently controlled. Therefore, an improved understanding of breakthrough pain and its management is essential for all physicians caring for patients with cancer. This article reviews the definition, clinical manifestations, accurate diagnostic strategies, and optimal treatment options for breakthrough pain in patients with cancer. This review focuses on the efficacy and safety of rapid-onset opioids, which are the primary rescue drugs for breakthrough pain.

Fentanyl in cancer pain management: avoiding hasty judgments and discerning its potential benefits

Cancer pain is an important challenge in treatment and requires a rapid onset of action for its control. In particular, breakthrough cancer pain (BTcP) should be adequately controlled with a stable dose of a short-acting oral opioid. Fentanyl is a synthetic, highly selective opioid with many advantageous chemical properties, including high lipophilicity and distinct pharmacokinetic properties. It is recommended for pain management in a variety of settings, including acute pain, chronic pain and BTcP. To date, its variously designed formulations allow non-invasive administration; amongst others, sublingual fentanyl has proven useful in the management of BTcP and in improving the quality of life of patients with cancer. This review provides an update on the management of BTcP with fentanyl, with consideration of safety, as it remains an important tool in the treatment of cancer pain.

Intravenous Patient-Controlled Analgesia Versus Oral Opioid to Maintain Analgesia for Severe Cancer Pain: A Randomized Phase II Trial

BACKGROUND

Optimal analgesic maintenance for severe cancer pain is unknown. This study evaluated the efficacy and safety of intravenous patient-controlled analgesia (IPCA) with continuous infusion plus rescue dose or bolus-only dose versus conventional oral extended-release morphine as a background dose with normal-release morphine as a rescue dose to maintain analgesia in patients with severe cancer pain after successful opioid titration.

METHODS

Patients with persistent severe cancer pain (≥7 at rest on the 11-point numeric rating scale [NRS]) were randomly assigned to 1 of 3 treatment arms: (A1) IPCA hydromorphone with bolus-only dose where dosage was 10% to 20% of the total equianalgesic over the previous 24 hours (TEOP24H) administered as needed, (A2) IPCA hydromorphone with continuous infusion where dose per hour was the TEOP24H divided by 24 and bolus dosage for breakthrough pain was 10% to 20% of the TEOP24H, and (B) oral extended-release morphine based on TEOP24H/2 × 75% (because of incomplete cross-tolerance) every 12 hours plus normal-release morphine based on TEOP24H × 10% to 20% for breakthrough pain. After randomization, patients underwent IPCA hydromorphone titration for 24 hours to achieve pain control before beginning their assigned treatment. The primary endpoint was NRS over days 1 to 3.

RESULTS

A total of 95 patients from 9 oncology study sites underwent randomization: 30 into arm A1, 32 into arm A2, and 33 into arm B. Arm B produced a significantly higher NRS over days 1 to 3 compared with arm A1 or A2 (P<.001). Daily NRS from day 1 to day 6 and patient satisfaction scores on day 3 and day 6 were worse in arm B. Median equivalent-morphine consumption increase was significantly lower in A1 (P=.024) among the 3 arms. No severe adverse event occurred in any arm.

CONCLUSIONS

Compared with oral morphine maintenance, IPCA hydromorphone for analgesia maintenance improves control of severe cancer pain after successful titration. Furthermore, IPCA hydromorphone without continuous infusion may consume less opioid.

Rapid-Onset Opioids for Management of Breakthrough Cancer Pain: Considerations for Daily Practice

Background and Objective

Rapid-onset opioids (ROOs) are effective treatments for breakthrough cancer pain (BTcP) given their rapid onset of action and relatively short duration of analgesia. The aim of this article is to describe specific considerations for the use of ROOs in daily practice, focusing on dose titration and treatment of specific populations.

Type of Review

We conducted a narrative review on the use of ROOs for BTcP. We selected papers according to the following search terms: “breakthrough cancer pain” and “rapid onset opioids”.

Results

ROOs may be considered as the most suitable drugs to treat BTcP and can be used “on-demand”. Several fentanyl formulations are available and have been associated with control of BTcP and with improvement in quality of life. Various titration schemes have been used to optimize ROO dosing; however, a dose-proportional scheme could be considered safe and effective in most patients. Specific formulations may be more suitable for specific patient subgroups; for example, patients with oral mucositis may prefer intranasal to oral formulations. Moreover, elderly patients or those without caregivers should be clearly educated on the use of these formulations. A key element in achieving successful treatment of BTcP is awareness of the barriers to pain management, including poor overall assessment, patient reluctance to take opioids or report pain, and physician reluctance to prescribe opioids.

Conclusion

A personalized approach is fundamental when prescribing a medication for BTcP, and careful attention should be given to drug choice and route of administration, and to the need for alternative therapeutic options.

Prevalence, Clinical Characteristics, and Management of Episodic Dyspnea in Advanced Lung Cancer Outpatients: A Multicenter Nationwide Study-The INSPIRA-DOS Study

Background: Episodic dyspnea (ED) is a common problem in patients with advanced lung cancer (LC). However, the prevalence of ED and other related aspects in this patient population is not known. Objectives: To assess and describe the prevalence, clinical features, treatment, and risk factors for ED in outpatients with advanced LC. Design: Multicenter cross-sectional study. Subjects: Consecutive sample of adult outpatients with advanced LC. Measurements: We assessed background dyspnea (BD), the characteristics, triggers, and management of ED. Potential ED risk factors were assessed through multivariate logistic regression. Results: A total of 366 patients were surveyed. Overall, the prevalence of ED was 31.9% (90% in patients reporting BD). Patients reported a median of one episode per day (interquartile range [IQR]: 1-2), with a median intensity of 7/10 (IQR: 5-8.25). ED triggers were identified in 89.9% of patients. ED was significantly associated with chronic obstructive pulmonary disease (p = 0.011), pulmonary vascular disease (p = 0.003), cachexia (p = 0.002), and palliative care (p < 0.001). Continuous oxygen use was associated with higher risk of ED (odds ratio: 9.89; p < 0.001). Opioids were used by 44% patients with ED. Conclusions: ED is highly prevalent and severe in outpatients with advanced LC experiencing BD. The association between intrathoracic comorbidities and oxygen therapy points to alveolar oxygen exchange failure having a potential etiopathogenic role in ED in this population. Further studies are needed to better characterize ED in LC to better inform treatments and trial protocols.

Understanding the Chameleonic Breakthrough Cancer Pain

Breakthrough cancer pain (BTcP) is a variegated phenomenon, that often presents in different ways in each individual, and may change its presentation in the same individual during the course of disease. An appropriate assessment is fundamental for depicting the pattern of BTcP in individuals. This information is determinant for a personalised management of BTcP. The use of opioids as needed, is recommended for the management of BTcP. There are several options which should be chosen according to the individual pattern of BTcP. In general, a drug with a short onset and offset should be preferred. Although oral opioids may still have specific indications, fentanyl products have been found to be more rapid and effective, providing analgesia in 5-15 min. The most controversial point regards the opioid dose to be used. The presence of tolerance suggests using a dose that is proportional to the dose used for background analgesia. In contrast, regulatory studies have suggested using the minimal available dose to be titrated until the effective dose. Further large studies should definitely settle this never-ending question.

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.

Breakthrough pain in cancer patients: prevalence, mechanisms and treatment options

PURPOSE OF REVIEW

The aim of this article was to examine the definition, the characteristics, and the management of breakthrough cancer pain (BTP) in cancer patients by a critical review of recent literature.

RECENT FINDINGS

BTP should be more correctly defined as an episode of severe intensity in patients receiving an adequate treatment with opioids able to provide at least mild analgesia. BTP is a heterogeneous condition as episodes vary between individuals. BTP can be classified into two big distinct pictures: spontaneous-type and incident-type pain. The principal pharmacological treatment of BTP is represented by the administration of opioids as needed. Recent reviews revealed that transmucosal preparation of fentanyl provided superior and more rapid pain relief as compared with placebo in the first 30 min after dosing. Few comparison studies among fentanyl products have been performed.Finally, although dose titration was recommended for years, a meaningful dosing according to the level of opioid tolerance may enhance the advantages of such products.

SUMMARY

BTP represents a serious problem reported by many cancer patients despite receiving regular use of opioids. Subgroups of breakthrough pain have been identified. Different modalities of pharmacological interventions are available. Further studies are warranted to assess the net benefit of these drugs to assist decision-making by patients, clinicians, and payers according to individual clinical conditions.

Fentanyl Buccal Tablet vs. Oral Morphine in Doses Proportional to the Basal Opioid Regimen for the Management of Breakthrough Cancer Pain: A Randomized, Crossover, Comparison Study

CONTEXT

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

OBJECTIVES

The aim of this randomized, crossover, controlled study was to compare efficacy and safety of fentanyl buccal tablets (FBTs) and oral morphine (OM), given in doses proportional to opioid daily doses.

METHODS

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

RESULTS

In total, 263 episodes of BTcP were treated. A statistical difference in changes in pain intensity-decrease of ≥33% and ≥50%-between the two groups was observed at T15 and T30 (P < 0.0005). No severe adverse effects after study drug administration were observed.

CONCLUSION

When used in doses proportional to the basal opioid regimen, FBT showed a clear superiority and was well tolerated when compared with OM during the first 30 minutes, which is the approximate target for a timely intervention required for a BTcP medication.

Relationship between onset of pain relief and patient satisfaction with fentanyl pectin nasal spray for breakthrough pain in cancer

BACKGROUND

Satisfaction with pain relief in patients with breakthrough pain in cancer (BTPc) has typically been assessed by overall efficacy without consideration of the rapidity of that response.

OBJECTIVE

To determine the relationship between speed of onset of pain relief and patient satisfaction for treated BTPc episodes overall and for individual treatments.

DESIGN

Pooled data from two randomized, double-blinded crossover studies.

SETTING/SUBJECTS

Patients having 1-4 BTPc episodes per day on ≥60 mg/day oral morphine or equivalent. Episodes treated with fentanyl pectin nasal spray (FPNS; 100-800 μg), immediate-release morphine sulfate (IRMS), or placebo.

MEASUREMENTS

Pain intensity was measured on an 11-point scale (5-60 minutes posttreatment); satisfaction was measured on a 4-point scale (30 and 60 minutes). The primary analysis assessed the overall relationship of time to onset of pain relief (pain intensity difference [PID]≥1) or time to clinically meaningfully reduction in pain (PID≥2) versus patient satisfaction and overall pain intensity (summed pain intensity difference at 30 [SPID30] and 60 minutes [SPID60]) assessed by analysis of variance (ANOVA). A secondary analysis assessed whether satisfaction was different between treatments using a within-patient comparison.

RESULTS

Eight hundred thirty-one FPNS-treated, 368 IRMS-treated, and 200 placebo-treated episodes were analyzed. Overall, within the pool there was a statistically significant relationship between time to onset of pain relief (PID≥1 and PID≥2) and patient satisfaction (both speed of relief and overall) at 30 and 60 minutes (p<0.001); this relationship was also true within individual treatment groups (p<0.01). Similar results were found for overall pain intensity reduction. When treatment groups were compared using within-patient data, FPNS provided earlier onset of pain relief than IRMS or placebo (p<0.05), which translated into better satisfaction at 60 minutes (p<0.01).

CONCLUSIONS

Earlier onset of pain relief resulted in greater patient satisfaction and overall relief of pain; between-treatment comparisons showed that FPNS provided earlier pain relief and greater satisfaction than IRMS or placebo.

Breakthrough cancer pain (BTcP): a synthesis of taxonomy, pathogenesis, therapy, and good clinical practice in adult patients in Italy

Pain presents in 80% of patients with advanced cancer, and 30% have periods of increased pain due to fluctuating intensity, known as breakthrough cancer pain (BTcP). BTcP is high-intensity, short-duration pain occurring in several episodes per day and is non-responsive to treatment. The clinical approach to BTcP is variable. A review of the literature was performed to provide clinicians and practitioners with a rational synthesis of the ongoing scientific debate on BTcP and to provide a basis for optimal clinical approach to BTcP in adult Italian patients. Data show that circadian exacerbations of pain should be carefully monitored, differentiating, if possible, between fluctuations of background pain (BP), end-of-dose effect, and BTcP. BTcP should be monitored in all care contexts in clinical practice and each care facility must have all the medications and products approved for use in BTcP at their disposal. Data show that knowledge about medications for BTcP is lacking: medications for BTcP treatment are not interchangeable, although containing the same active substance; each physician must know the specific characteristics of each medication, its pharmacological properties, limitations in clinical practice, specifics relating to titration and repeatability of administration, and technical specifics relating to the accessibility and delivery. Importantly, before choosing a rapid-onset opioid (ROO), it is essential to deeply understand the status of patient and the characteristics of their family unit/caregivers, taking into account the patient’s progressive loss of autonomy and/or cognitive-relational functionality. When BTcP therapy is initiated or changed, special attention must be paid to training the patient and family members/caregivers, providing clear instructions regarding the timing of drug administration. The patient must already be treated effectively with opioids before introducing ROOs for control of BTcP.

Budget impact analysis of the fentanyl buccal tablet for treatment of breakthrough cancer pain

BACKGROUND

The purpose of this study was to assess the economic impact of the fentanyl buccal tablet for the management of breakthrough cancer pain (BTcP) in Spain.

METHODS

A 4-year budget impact model was developed for the period 2012-2015 for patients with BTcP from the perspective of the Spanish National Health System. BTcP products included in this model were rapid-onset opioids containing fentanyl (buccal, sublingual, or nasal transmucosal). Prevalence data on cancer, BTcP, opioid use, and number of BTcP episodes were obtained from the literature. Input data on health care resources associated with opioid use and opioid-induced side effects were obtained by consulting experts in oncology from different Spanish hospitals. Resources used included drugs, medical and emergency visits, other nonpharmacologic treatments, and treatment of opioid-induced side effects. Unit costs were obtained from the literature, and a 3% discount rate was applied to costs. Based on the unit costs for drugs and health care resources, the annual BTcP treatment costs per patient associated with each fentanyl product were determined to estimate the overall budget impact based on the total treatment population and the percentage of drug utilization associated with each product. One-way sensitivity analyses were conducted to test the robustness of the model.

RESULTS

Patients treated with oral opioids for BTcP were estimated at 23,291 in 2012, with an increase up to 23,413 in 2015. The average annual budget savings, with an increase of fentanyl buccal tablets, fentanyl sublingual tablets, and intranasal fentanyl spray, and a decrease in oral transmucosal fentanyl citrate, was estimated at €2.6 million, which represents a 0.5% decrease in the total costs of BTcP over the next 4 years. Results of the sensitivity analysis showed that the model was most sensitive to drug cost per day for the fentanyl buccal tablet. A 50% decrease in the daily cost of the fentanyl buccal tablet resulted in the largest overall decrease in budget impact of €5.4 million.

CONCLUSION

The increase in use of the fentanyl buccal tablet leads to overall savings in the budget impact for the Spanish National Health System. Although the economic impact of treatment for BTcP was shown to increase over 4 years due to population growth, the average annual cost per patient was reduced by €29 with increased use of the fentanyl buccal tablet.

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.

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.

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.

Consistency of efficacy, patient acceptability, and nasal tolerability of fentanyl pectin nasal spray compared with immediate-release morphine sulfate in breakthrough cancer pain

CONTEXT

We recently reported that fentanyl pectin nasal spray (FPNS) provides superior pain relief from breakthrough cancer pain (BTCP) compared with immediate-release morphine sulfate (IRMS), with significant effects by five minutes and clinically meaningful pain relief from 10 minutes postdose.

OBJECTIVES

To report the consistency of efficacy, tolerability, and patient acceptability of FPNS vs. IRMS.

METHODS

Patients (n=110) experiencing one to four BTCP episodes/day while taking ≥60 mg/day oral morphine (or equivalent) for background pain entered a double-blind, double-dummy (DB/DD), multiple-crossover study. Those who completed an open-label titration phase (n=84) continued to a DB/DD phase; 10 episodes were randomly treated with FPNS and overencapsulated placebo or IRMS and nasal spray placebo (five episodes each). Pain intensity (PI) and pain relief scores were assessed. Patient acceptability scores were assessed at 30 and 60 minutes. Safety and tolerability were assessed by adverse events (AEs) and nasal assessments.

RESULTS

Per-episode analysis revealed that FPNS consistently provided relief from pain more rapidly than IRMS; by 10 minutes, there were significant differences in PI difference scores and in the percentages of episodes showing clinically meaningful pain relief (P<0.05). Overall acceptability scores were significantly greater for FPNS than for IRMS at 30 (P<0.01) and 60 (P<0.05) minutes. Patients were "satisfied/very satisfied" with the convenience (79.8%) and ease of use (77.2%) of FPNS. Only 4.7% of patients withdrew from titration because of AEs; no significant nasal effects were reported.

CONCLUSION

This study demonstrates that FPNS is efficacious, well accepted, and well tolerated by patients with BTCP.

Efficacy of intranasal fentanyl spray versus other opioids for breakthrough pain in cancer

OBJECTIVE

To compare the efficacy of intranasal fentanyl spray (INFS), oral transmucosal fentanyl citrate (OTFC), fentanyl buccal tablet (FBT) and oral morphine (OM) for the treatment of breakthrough cancer pain (BTCP).

METHODS

A systematic literature review (Medline, EMBASE, BIOSIS; 1996-2007) identified six randomised controlled trials (RCTs) investigating the effects of INFS, OTFC, FBT and OM for the treatment of BTCP. The endpoint of interest was pain intensity difference (PID, reported on a 0-10 numeric rating scale [NRS]) up to 60 minutes after intake. Results of all trials were analysed simultaneously with a mixed treatment comparison (extended meta-analysis). MTC can be considered a valid method when included studies are comparable regarding effect modifying baseline patient and study characteristics.

RESULTS

INFS provided the greatest reduction in pain relative to placebo: PID 1.7 points (95% CrI: 1.4; 1.9) at 15 minutes, 2.0 (1.6; 2.3) at 30 minutes, 2.0 (1.5; 2.4) at 45 minutes and 1.9 (1.5; 2.4) at 60 minutes. PID for OTFC and FBT relative to placebo were 0.4 (0.0; 0.8) and 0.5 (0.3; 0.7) at 15 minutes. Both treatments provided a reduction in pain superior to placebo at other time points. INFS displayed a more than 99% probability of providing the greatest pain reduction out of all interventions compared at 15 minutes after intake. This was maintained for any measured time point before 45 minutes when compared to FBT and for any measured time point before 60 minutes when compared to OTFC. Only from 45 minutes onwards did OM show a greater pain reduction than placebo.

CONCLUSION

Based on currently available evidence, INFS is expected to provide the greatest improvement in the treatment of BTCP. Due to its slow onset to effect OM cannot be considered an efficacious treatment for BTCP.