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

Clinical and pharmacokinetics overview of intranasal administration of fentanyl

Due to the presence of large surfaces and high blood supply, drug delivery through the nasal route of administration is the appropriate route to administrate drugs with rapid onsets of action. Bypassing first-pass metabolism can increase drug bioavailability. The physicochemical properties of fentanyl led to a need to develop formulations for delivery by multiple routes. Several approved inter-nasal fentanyl products in Europe and the USA have been used in prehospital and emergency departments to treat chronic cancer pain and used to treat severe acute abdominal and flank pain. Analgesia durations and onsets were not significantly different between intranasal and intravenous fentanyl in patients with cancer breakthrough pain and were well-tolerated in the long term. Intranasal Fentanyl (INF) at a 50 μg/ml concentration decreased renal colic pain to the lowest level in 30 min. Possible adverse effects specific to INF are epistaxis, nasal wall ulcer, rhinorrhea, throat irritation, dysgeusia, nausea, and vomiting. However, there is limited available literature about the serious adverse effects of INF in adults and children. Intranasal Fentanyl Spray (INFS) results in significantly higher plasma concentrations and has a lower Tmax than oral transmucosal formulation, and the bioavailability of fentanyl in intranasal formulations is very high (89 %), particularly in pectin-containing formulations such as PecFent and Lazanda.

Breakthrough and Episodic Cancer Pain from a Palliative Care Perspective

Cancer pain intensity (PI) fluctuates, but the relationship between pain flares and background pain with respect to pain management is not settled. We studied how flare and background PIs corresponded with treatment results for background cancer pain. Patients admitted to an acute palliative care unit with average and/or worst PI ≥ 1 on the 11-point numeric rating scale were included. Average and worst PI at admission and average PI at discharge were collected. We examined how the difference and ratio between worst and average PI and average PI at admission, were associated with average PI development during hospitalization. Positive differences between worst and average PI at admission were defined as pain flares. Ninety out of 131 patients had pain flares. The reduction in average PI for patients with flares was 0.9 and for those without, 1.9 (p = 0.02). Patients with large worst minus average PI differences reported the least improvement, as did those with large worst/average PI ratios. Patients with pain flares and average PI ≤ 4 at admission had unchanged average PI during hospitalization, while those with pain flares and average PI > 4 experienced pain reduction (2.1, p < 0.001). Large pain flares, in absolute values and compared to background PI, were associated with inferior pain relief.

High-rate breakthrough cancer pain and tumour characteristics - literature review and case series

Cancer pain requires careful comprehensive patient evaluation and an appropriate and personalized clinical approach by a trained multidisciplinary team. The proper assessment of breakthrough cancer pain (BTcP) is part of an all-inclusive multidimensional evaluation of the patient. The aim of this narrative review is to explore the relationship between high-rate BTcP, which strongly impacts health- related quality of life and tumour characteristics, in the face of novel approaches that should provide guidance for future clinical practice. The presentation of short, emblematic clinical reports also promotes knowledge of BTcP, which, despite the availability of numerous therapeutic approaches, remains underdiagnosed and undertreated. This article is part of the Management of breakthrough cancer pain Special Issue: https://www.drugsincontext.com/special_issues/management-of-breakthrough-cancer-pain.

Predicting tolerability of high-dose fentanyl buccal tablets in cancer patients

BACKGROUND & AIMS

Fentanyl buccal tablets (FBTs) are a rapid-onset opioid indicated for breakthrough cancer pain (BTcP) and FBT titration is needed to optimize BTcP management. We aimed to predict which patients could tolerate a high dose of FBT (400 μg or more at a time).

METHODS

A retrospective analysis was performed to assess the final FBT dose. The final FBT doses were compared according to the clinical features. The prediction accuracy of patients tolerant of 400 μg or higher FBT was compared using the area under the receiver operating characteristic (ROC) curves. A risk scoring model based on the odds ratio (OR) was developed from the final multivariable model, and patients were assigned into two groups: low tolerance (0-1 point) and high tolerance (2-3 points).

RESULTS

Among 131 patients, the most frequently effective dose of FBT was 200 μg (54%), followed by 100 μg (30%). The median value of morphine equivalent daily doses (MEDD) was 60 mg/day, and the most common daily use was 3-4 times/day. In multivariable analysis, male sex, younger age, and use of FBTs three or more times per day were independently associated with high-dose FBT. According to the risk scoring model, the patients with a final FBT of 400 μg or higher were significantly more in the high tolerance group (17%) compared to the low tolerance group (3%; p = 0.023).

CONCLUSIONS

According to the dose relationship between the final FBT dose and the clinical features, three factors (sex, age, daily use of FBT) were independently associated with the final dose of FBT. Our risk score model could help predict tolerance to high-dose FBT and guide the titration plan for BTcP.

Prostate cancer induced bone pain: pathobiology, current treatments and pain responses from recent clinical trials

PURPOSE

Metastatic spread of prostate cancer to the skeleton may result in debilitating bone pain. In this review, we address mechanisms underpinning the pathobiology of metastatic prostate cancer induced bone pain (PCIBP) that include sensitization and sprouting of primary afferent sensory nerve fibres in bone. We also review current treatments and pain responses evoked by various treatment modalities in clinical trials in this patient population.

METHODS

We reviewed the literature using PubMed to identify research on the pathobiology of PCIBP. Additionally, we reviewed clinical trials of various treatment modalities in patients with PCIBP with pain response outcomes published in the past 7 years.

RESULTS

Recent clinical trials show that radionuclides, given either alone or in combination with chemotherapy, evoked favourable pain responses in many patients and a single fraction of local external beam radiation therapy was as effective as multiple fractions. However, treatment with chemotherapy, small molecule inhibitors and/or immunotherapy agents, produced variable pain responses but pain response was the primary endpoint in only one of these trials. Additionally, there were no published trials of potentially novel analgesic agents in patients with PCIBP.

CONCLUSION

There is a knowledge gap for clinical trials of chemotherapy, small molecule inhibitors and/or immunotherapy in patients with PCIBP where pain response is the primary endpoint. Also, there are no novel analgesic agents on the horizon for the relief of PCIBP and this is an area of large unmet medical need that warrants concerted research attention.

Pharmacokinetic Characterisation and Comparison of Bioavailability of Intranasal Fentanyl, Transmucosal, and Intravenous Administration through a Three-Way Crossover Study in 24 Healthy Volunteers

Background

For more than 60 years, the synthetic opioid fentanyl has been widely used in anaesthesia and analgesia. While the intravenous formulation is primarily used for general anaesthesia and intensive care settings, the drug's high lipophilic properties also allow various noninvasive routes of administration. Published data suggest that intranasal administration is also attractive for use as intranasal patient-controlled analgesia (PCA). A newly developed intranasal fentanyl formulation containing 47 μg fentanyl, intravenous fentanyl, and oral transmucosal fentanyl citrate were characterised, and bioavailability was compared to assess the suitability of the intranasal formulation for an intranasal PCA product.

Methods

27 healthy volunteers were enrolled in a single-centre, open-label, randomised (order of treatments), single-dose study in a three-period crossover design. The pharmacokinetics of one intranasal puff of fentanyl formulation (47 μg, 140 mL per puff), one short intravenous infusion of 50 μg fentanyl, and one lozenge with an integrated applicator (200 μg fentanyl) were studied, and bioavailability was calculated. Blood samples were collected over 12 hours, and plasma concentrations of fentanyl were determined by HPLC with MS/MS detection.

Results

24 volunteers completed the study. The geometric mean of AUC_0-tlast was the highest with oral transmucosal administration (1106 h ∗ pg/ml, CV% = 32.86), followed by intravenous (672 h ∗ pg/ml, CV% = 32.18) and intranasal administration (515 h ∗ pg/ml, CV% = 30.10). C _max was 886 pg/ml (CV% = 59.38) for intravenous, 338 pg/ml (CV% = 45.61) for intranasal, and 310 pg/ml (CV% = 29.58) for oral transmucosal administration. t _max was shortest for intravenous administration (0.06 h, SD = 0.056), followed by intranasal (0.21 h, SD = 0.078) and oral transmucosal administration (1.20 h, SD = 0.763). Dose-adjusted absolute bioavailability was determined to be 74.70% for the intranasal formulation and 41.25% for the oral transmucosal product. In total, 38 adverse events (AEs) occurred. Fourteen AEs were potentially related to the investigational items. No serious AE occurred.

Conclusion

Pharmacokinetic parameters and bioavailability of the investigated intranasal fentanyl indicated suitability for its intended use as an intranasal PCA option.

Breakthrough cancer pain in 2020

PURPOSE OF REVIEW

An overview on breakthrough cancer pain (BTCP), including inherent limitations of the terminology, assessment, clinical presentation, and treatment options.

RECENT FINDINGS

The estimated prevalence of BTCP is dependent on the defined cutoffs for controlled background pain and the magnitude of the pain flare. In addition, pain flares outside the definition of BTCP are prevalent. In the 11th Revision of the International Classification of Diseases, the temporal characteristics of cancer pain are described as continuous background pain and intermittent episodic pain. BTCP should be assessed by validated methods, and the patient perspective should be included. The pain may be related to neoplastic destruction of bone, viscera, or nerve tissue and is characterized by rapid onset, high intensity, and short duration. Treatment directed towards painful metastases must be considered. Due to pharmacological properties mirroring the pain characteristics, transmucosal fentanyl formulations are important for the treatment of BTCP. Oral immediate release opioids can be used for slow-onset or predictable BTCP. For more difficult pain conditions, parenteral, or even intrathecal pain medication, may be indicated.

SUMMARY

All clinically relevant episodic pains must be adequately treated in accordance with the patient's preferences. Transmucosal fentanyl formulations are effective for BTCP.

Drug utilization study on immediate release Fentanyl in Spain. Prevalence, incidence, and indication

PURPOSE

We aimed to characterize the trends of immediate release fentanyl (IRF) use in Spain between 2012 and 2017 and indication for its use. IRF drugs are rapid-acting opioids approved to treat breakthrough cancer pain (BTCP) in patients already receiving maintenance opioid therapy for chronic cancer pain. A substantial increase in consumption of IRF has been observed with emerging cases of abuse and dependence, most of them in noncancer patients.

METHODS

An ecological descriptive consumption study with aggregated data from drug dispensed by community pharmacies and reimbursed by the National Health System in which Defined Daily Doses per 10 000 inhabitants (DID) were calculated and a retrospective cohort study using data from the Spanish Database for Pharmacoepidemiological Research in Primary Care in which participants entered the cohort study after 1 year with the Primary Care Practitioners were performed. Annual prevalence and incidence rate of IRF use were estimated by sex and calendar year. Potential indication was also assessed.

RESULTS

IRF use in Spain increased from 2.1 DID in 2012 to 3.8 DID in 2017. The incidence rate and prevalence increased in 53% and 74%, respectively. Patients without previous cancer or BCTP diagnosis represented 27% of incident users, predominantly women. Half of patients with noncancer-related diagnosis had a musculoskeletal disorder linked to the first IRF prescription.

CONCLUSIONS

National consumption and new IRF users in Spain increased over the study period and one quarter of patients did not have a BTCP or cancer diagnosis registered in their clinical record.

Working towards a consensus on the oncological approach of breakthrough pain: a Delphi survey of Spanish experts

Purpose

There is a lack of standards for the diagnosis, assessment and management of breakthrough cancer pain (BTcP). La Fundación ECO (the Foundation for Excellence and Quality in Oncology) commissioned a study to establish a consensus and lay the foundations for the appropriate management of BTcP in oncology patients.

Patients and methods

A modified Delphi survey comprising two rounds was used to gather and analyze data, which was conducted over the Internet. Each statement that reached a consensus with the respondents was defined as a median consensus score (MED) of ≥7, and agreement among panelists as an interquartile range (IQR) of ≤3.

Results

In total, 69 medical oncologists responded, with a broad consensus that BTcP implied exacerbations of high-intensity pain, as opposed to moderate pain. Furthermore, they concurred that appropriate diagnostic equipment is needed, and that rapid-onset fentanyl formulations should be the preferred treatment for BTcP management. The panelists agreed that a lack of appropriate information and training to attend to patients, as well as limited patient visitation rights, were barriers to effective BTcP management. Regarding gaps in detected knowledge, the panelists were unsure of the measures necessary to assess the burden of the disease on the patient’s quality of life and associated medication costs. Alongside this, there was a lack of awareness of the technical specifics of the different formulations of rapid-onset fentanyl.

Conclusion

These results represent the current status of BTcP management. They may inform recommendations and provide a framework for future research.