A One Year Health Economic Model Comparing Transdermal Fentanyl with Sustained-Release Morphine in the Treatment of Chronic Noncancer Pain

Transdermal drug delivery systems for fighting common viral infectious diseases

Transdermal drug delivery systems (TDDS) have many advantages and represent an excellent alternative to oral delivery and hypodermic injections. TDDS are more convenient and less invasive tools for disease and viral infection treatment, prevention, detection, and surveillance. The emerging development of microneedles for TDDS has facilitated improved skin barrier penetration for the delivery of macromolecules or hydrophilic drugs. Microneedle TDDS patches can be fabricated to deliver virus vaccines and potentially provide a viable alternative vaccine modality that offers improved immunogenicity, thermostability, simplicity, safety, and compliance as well as sharp-waste reduction, increased cost-effectiveness, and the capacity for self-administration, which could improve vaccine distribution. These advantages make TDDS-based vaccine delivery an especially well-suited option for treatment of widespread viral infectious diseases including pandemics. Because microneedle-based bioassays employ transdermal extraction of interstitial fluid or blood, they can be used as a minimally invasive approach for surveying disease markers and providing point-of-care (POC) diagnostics. For cutaneous viral infections, TDDS can provide localized treatment with high specificity and less systemic toxicity. In summary, TDDS, especially those that employ microneedles, possess special attributes that can be leveraged to reduce morbidity and mortality from viral infectious diseases. In this regard, they may have considerable positive impact as a modality for improving global health. In this article, we introduce the possible role and summarize the current literature regarding TDDS applications for fighting common cutaneous or systemic viral infectious diseases, including herpes simplex, varicella or herpes zoster, warts, influenza, measles, and COVID-19.

A Systematic Review of Economic Evaluation Studies of Drug-Based Non-Malignant Chronic Pain Treatment

BACKGROUND AND OBJECTIVE

Chronic pain is a highly prevalent problem, involving high costs and seriously affecting a patient's quality of life. This review aimed to systematically review economic evaluations of pharmacological-based treatments for non-malignant chronic pain and to compare different treatment approaches with regard to their economic profile.

METHODS

PubMed and Scopus were systematically searched in April 2016. Studies were included if quality-adjusted life years and incremental cost-effectiveness ratios were reported. Quality assessment was carried out by using La Torre's weighted scale on the Drummond checklist. Costs were converted into US$2014.

RESULTS

Fourteen economic evaluations met the inclusion criteria. Three treatment categories identified were: opioids, anticonvulsants, and anti-depressants. Compared to anticonvulsants and antidepressant, opioids had lower ICER. Transdermal buprenorphine showed an ICER of about US$11,000.00 while pregabalin showed an ICER of US$19,200. Studies included showed a diversity of methodological approaches, such as different modeling approaches and different perspectives (NHS and private payer).

CONCLUSION

There are limitations to the success of making appropriate recommendations about which treatment is most cost-effective due to considerable variability between treatments, pain syndromes, and drug dosages. Opioids may have lower ICER, but the societal implications of the opioid epidemic and overdose deaths should be taken into account when coming to general conclusions about their cost-effectiveness. To ensure correct resource allocation as well as the best benefit for patients, uniform and standardized approaches of cost and outcome measurement in economic evaluations of chronic are needed.

Economic evaluation in chronic pain: a systematic review and de novo flexible economic model

There is unmet need in patients suffering from chronic pain, yet innovation may be impeded by the difficulty of justifying economic value in a field beset by data limitations and methodological variability. A systematic review was conducted to identify and summarise the key areas of variability and limitations in modelling approaches in the economic evaluation of treatments for chronic pain. The results of the literature review were then used to support the development of a fully flexible open-source economic model structure, designed to test structural and data assumptions and act as a reference for future modelling practice. The key model design themes identified from the systematic review included: time horizon; titration and stabilisation; number of treatment lines; choice/ordering of treatment; and the impact of parameter uncertainty (given reliance on expert opinion). Exploratory analyses using the model to compare a hypothetical novel therapy versus morphine as first-line treatments showed cost-effectiveness results to be sensitive to structural and data assumptions. Assumptions about the treatment pathway and choice of time horizon were key model drivers. Our results suggest structural model design and data assumptions may have driven previous cost-effectiveness results and ultimately decisions based on economic value. We therefore conclude that it is vital that future economic models in chronic pain are designed to be fully transparent and hope our open-source code is useful in order to aspire to a common approach to modelling pain that includes robust sensitivity analyses to test structural and parameter uncertainty.

Cost-effectiveness analysis of levobupivacaine 0.5 %, a local anesthetic, infusion in the surgical wound after modified radical mastectomy

BACKGROUND AND OBJECTIVE

Effective treatment of postoperative pain contributes to decreasing the rate of complications as well as the total cost of the operated patients. The aim of this study was to analyze the costs and the efficiency of use of continuous infusion of levobupivacaine 0.5 % with the help of an infusion pump in modified radical mastectomy.

METHODS

A cost calculation of the analgesic procedures (continuous infusion of levobupivacaine 0.5 % [levobupivacaine group (LG)] or saline [saline group (SG)] (2 ml/h 48 h) has been carried out based on the data of a previous clinical trial (double-blind randomized study) of patients who underwent modified radical mastectomy surgery. The measure of the effectiveness was the point reduction of pain derived from the verbal numeric rating scale (VNRS). The usual incremental cost-effectiveness ratio (ICER) was performed.

RESULTS

Considering only the intravenous analgesia, overall costs were lower in LG, as less analgesia was used (EUR14.06 ± 7.89 vs. 27.47 ± 14.79; p < 0.001). In this study the costs of the infusion pump were not calculated as it was used by both groups and they offset each other. However, if the infusion pump costs were included, costs would be higher in the LG, (EUR91.89 ± 7.89 vs. 27.47 ± 14.79; p < 0.001) and then the ICER was -8.51, meaning that for every extra point of decrease in the pain verbal numerical rating score over the 2-day period, the cost increased by EUR8.51.

CONCLUSION

Infiltration of local anesthetics is an effective technique for controlling postoperative pain and the associated added costs are relatively low in relation to the total cost of mastectomy, therefore providing patients with a higher quality of care in the prevention of pain.

CLINICAL TRIALS REGISTRATION

clinicaltrials.gov: reference number NCT01389934. http://clinicaltrials.gov/show/NCT01389934

The cost of opioid-related adverse drug events

Opioids are the cornerstone of pain management; however, their use is associated with a variety of adverse drug events (ADEs) ranging from nausea and vomiting to urinary retention and respiratory depression. The purpose of this review is to describe the frequency and cost associated with different types of opioid-related ADEs to better understand their economic impact. A search of studies published in journals from 1946 to December, 2013, was conducted using MEDLINE and EMBASE. A total of 20 articles were reviewed. Data reflect a substantial economic burden of opioid-related ADEs resulting in high hospital costs, prolonged hospital stays, and substantial health care resource usage. Nausea, vomiting, and constipation are frequent and increased costs occur in all types of pain (surgical, nonsurgical, cancer, noncancer) in both inpatients and outpatients. Given the large economic burden of opioid-related ADEs, prevention rather than treatment may be the most effective strategy.

Opioid therapy pharmacogenomics for noncancer pain: efficacy, adverse events, and costs

Chronic non-cancer pain is a debilitating condition associated with high individual and societal costs. While opioid treatment for pain has been available for centuries, it is associated with high variability in outcome, and a considerable proportion of patients is unable to attain relief from symptoms while suffering adverse events and developing medication dependence. We performed a review of the efficacy of pharmacogenomic markers and their abilities to predict adverse events, dependence, and associated economic costs, focusing on two genes: OPRM1 and CYP2D6. Data sources were articles indexed by PubMed on or before August 6, 2013. Articles were first selected after review of their titles and abstracts, and full papers were read to confirm eligibility. Initially, fifty-two articles were identified. Of these, 17 were relevant to biological actions of pharmacogenomic markers and their effect on therapeutic efficacy, 16 to adverse events, 15 to opioid dependence, and eight to economic costs. In conclusion, increasing costs of opioid therapy have made the advances in pharmacogenomics an attractive solution to personalize care with unclear repercussions related to the impact on costs, morbidity, and outcomes. This intersection of pharmacoeconomics and pharmacogenomics presents a unique platform to further examine current advances in clinical medicine and their utility in cost-effective treatment of chronic pain.

Clinical simulation model of long-acting opioids for treatment of chronic non-cancer pain in the United States

OBJECTIVE

To evaluate costs and outcomes associated with initial tapentadol ER vs oxycodone CR for the treatment of chronic non-cancer pain (CNCP) in the US.

METHODS

This study developed a Monte-Carlo simulation based on the scientific foundation established by published models of long-acting opioids (LAO) in patients having moderate-to-severe CNCP. It estimates costs and outcomes associated with the use of tapentadol ER vs oxycodone CR over a 1-year period from the perspective of a US payer. LAO effectiveness and treatment-emergent adverse event (TEAE) rates are derived from clinical trials of tapentadol ER vs oxycodone CR; other inputs are based on published literature supplemented sparingly with clinical opinion. Sensitivity analyses consider the impact of real-world dosing patterns for LAO on treatment costs.

RESULTS

Initial tapentadol ER consistently demonstrates better outcomes than initial oxycodone CR (proportion of patients achieving adequate pain relief and no GI TEAE; acute TEAE-free days; days free of chronic constipation; quality-adjusted life days; productive working hours). While total costs with initial tapentadol ER are slightly (2.2%) higher than with initial oxycodone CR, nearly twice as many modeled patients in the initial tapentadol ER arm (29% vs 15%) achieve adequate pain relief and no GI TEAE compared to initial oxycodone CR. In sensitivity analyses, tapentadol ER becomes a dominant strategy when real-world dosing patterns are considered.

CONCLUSION

The additional costs to produce better outcomes (pain relief and no GI TEAE) associated with tapentadol ER are small in the context of double the likelihood of a patient response with tapentadol ER. When daily average consumption (DACON) for oxycodone CR is factored into the analysis, initial tapentadol ER becomes a dominant strategy. Our findings are both strengthened, and limited by the use of randomized trial-centric input parameters. These results should be validated as inputs from clinical practice settings become available.

Cost-effectiveness of tapentadol in severe chronic pain in Spain: a cost analysis of data from RCTs

BACKGROUND

Chronic pain is known to be a significant and common health problem. Tapentadol, a recently developed centrally active, oral analgesic agent is used to treat adults with severe chronic pain that can be adequately managed only with opioid analgesics. Tapentadol has been reported to provide an improved adverse-events (AE) profile compared with other potent opioid analgesics at similar levels of analgesia.

OBJECTIVES

The aim of this study was to compare the cost-effectiveness of tapentadol to that of opioids commonly used as first-line treatment of severe, chronic, nonmalignant pain from the perspective of the health care payer in Spain.

METHODS

A Markov state-transition model was developed to compare the cost-effectiveness of first-line treatment with tapentadol to that of oxycodone, morphine, and transdermal fentanyl (TDF) over a 1-year time horizon. Four health states were defined: (1) treatment discontinuation due to a severe AE; (2) treatment discontinuation due to a lack of efficacy; (3) occurrence of an AE that required medical treatment; and (4) no discontinuation and no AE. If a patient discontinued a treatment, he or she was switched to an alternative, second-line opioid. Data regarding efficacy, tolerability, and utility values (EQ-5D) were derived from randomized clinical trials. Clinical experts estimated the rates of switching to other opioids and the health care resource utilization associated with the treatment of severe chronic pain. Unit costs were derived from public price lists/tariff works and were calculated from the perspective of the National Spanish Health System. The robustness of the model results was tested in extensive sensitivity analyses in which event probabilities, costs, utilities, and treatment-switching rates were altered.

RESULTS

Data from 3 studies (1981 patients) were included in the model. Overall, the model predicted that initiating first-line treatment with tapentadol in patients with severe, chronic, nonmalignant pain was associated with lower costs and greater efficacy versus first-line treatment with oxycodone. Compared with morphine and TDF, tapentadol yielded incremental cost-effectiveness ratios of €2656 and €2069 per quality-adjusted life-year gained, respectively. On extensive 1-way and scenario analyses, findings on the cost-effectiveness of tapentadol were consistent. The probability that tapentadol would be cost-effective compared with each comparator at the willingness-to-pay threshold of €20,000 to €30,000/QALY gained exceeded 90%.

CONCLUSIONS

Based on the findings from the present model, tapentadol is likely to be a cost-effective first-line treatment in patients with severe, chronic, nonmalignant pain in Spain according to the commonly accepted willingness-to-pay thresholds. Compared with morphine and TDF, the incremental cost-effectiveness ratios were low; compared with oxycodone, tapentadol dominated, showing better quality-of-life outcomes at lower costs.

Pharmacoeconomic impact of adverse events of long-term opioid treatment for the management of persistent pain

Opioids are the most powerful analgesic drugs currently available and consequently form an essential part of the treatment options for malignant and non-malignant chronic pain. However, the benefits of these medications can be offset by gastrointestinal adverse events such as nausea, vomiting and constipation, as well as adverse events affecting the CNS. These occur relatively frequently in patients receiving long-term opioids for pain relief and are a cause of additional patient suffering and reduced work and social functioning, measured as reductions in quality-of-life outcomes. Consequently, adverse events are often the cause of treatment non-compliance or discontinuation (non-persistence). A literature search was conducted using BIOSIS Previews, EMBASE, Cochrane Collaboration and MEDLINE databases to identify references with specific relevance to the measurement of health outcomes related to adverse events of long-term opioid treatment of chronic pain. The results of this search highlighted that clinical interventions required to manage adverse events associated with opioids, and to provide alternative methods of pain control, both incur direct costs. These are largely driven by the cost of medical consults and drug supplies. Indirect costs are generated from work absences and reduced social functioning. Estimated preference ratings, providing an insight into the trade-off between effective pain control and adverse events, have shown that utility decrements associated with an increase in adverse-event severity were similar in size to those caused by a shift from well controlled to poorly controlled pain. Given the rising prevalence of chronic pain conditions (affecting one in five adult Europeans), the direct and indirect costs incurred from the management of adverse events with long-term opioids are likely to be multiplied, contributing to the socioeconomic burden of chronic pain. For this reason, the adverse-event profile of opioid-based analgesics should be improved to achieve more efficient long-term pain control.

Pharmacoeconomic impact of adverse events of long-term opioid treatment for the management of persistent pain

Opioids are the most powerful analgesic drugs currently available and consequently form an essential part of the treatment options for malignant and non-malignant chronic pain. However, the benefits of these medications can be offset by gastrointestinal adverse events such as nausea, vomiting and constipation, as well as adverse events affecting the CNS. These occur relatively frequently in patients receiving long-term opioids for pain relief and are a cause of additional patient suffering and reduced work and social functioning, measured as reductions in quality-of-life outcomes. Consequently, adverse events are often the cause of treatment non-compliance or discontinuation (non-persistence). A literature search was conducted using BIOSIS Previews, EMBASE, Cochrane Collaboration and MEDLINE databases to identify references with specific relevance to the measurement of health outcomes related to adverse events of long-term opioid treatment of chronic pain. The results of this search highlighted that clinical interventions required to manage adverse events associated with opioids, and to provide alternative methods of pain control, both incur direct costs. These are largely driven by the cost of medical consults and drug supplies. Indirect costs are generated from work absences and reduced social functioning. Estimated preference ratings, providing an insight into the trade-off between effective pain control and adverse events, have shown that utility decrements associated with an increase in adverse-event severity were similar in size to those caused by a shift from well controlled to poorly controlled pain. Given the rising prevalence of chronic pain conditions (affecting one in five adult Europeans), the direct and indirect costs incurred from the management of adverse events with long-term opioids are likely to be multiplied, contributing to the socioeconomic burden of chronic pain. For this reason, the adverse-event profile of opioid-based analgesics should be improved to achieve more efficient long-term pain control.

Estimating drug costs in economic evaluations in Ireland and the UK: an analysis of practice and research recommendations

Cost estimates for the drug of interest, its comparator and concomitant drugs are an important component of pharmacoeconomic evaluations. However, whilst in general considerable efforts are made by analysts to ensure valid and accurate parameter inputs, the methods for estimating drug costs are often lacking. We reviewed recent pharmacoeconomic evaluations undertaken in Ireland and the UK and documented the sources of data for drug costs and the methods of cost estimation. Methods were often inadequately described and, where adequate information was available, there was considerable variation and limitations in the methods used, thereby reducing the comparability of studies. Data from a sample of studies from other Northern European countries suggested that the findings from Ireland and the UK were not atypical. In order to improve current practice we suggest a methodological checklist for use in future studies.

Dermal and Transdermal Drug Delivery Systems: Current and Future Prospects

The protective function of human skin imposes physicochemical limitations to the type of permeant that can traverse the barrier. For a drug to be delivered passively via the skin it needs to have adequate lipophilicity and also a molecular weight <500 Da. These requirements have limited the number of commercially available products based on transdermal or dermal delivery. Various strategies have emerged over recent years to optimize delivery and these can be categorized into passive and active methods. The passive approach entails the optimization of formulation or drug carrying vehicle to increase skin permeability. Passive methods, however do not greatly improve the permeation of drugs with molecular weights >500 Da. In contrast active methods that normally involve physical or mechanical methods of enhancing delivery have been shown to be generally superior. Improved delivery has been shown for drugs of differing lipophilicity and molecular weight including proteins, peptides, and oligonucletides using electrical methods (iontophoresis, electroporation), mechanical (abrasion, ablation, perforation), and other energy-related techniques such as ultrasound and needless injection. However, for these novel delivery methods to succeed and compete with those already on the market, the prime issues that require consideration include device design and safety, efficacy, ease of handling, and cost-effectiveness. This article provides a detailed review of the next generation of active delivery technologies.

Transdermal drug delivery systems: skin perturbation devices

Human skin serves a protective function by imposing physicochemical limitations to the type of permeant that can traverse the barrier. For a drug to be delivered passively via the skin it needs to have a suitable lipophilicity and a molecular weight < 500 Da. The number of commercially available products based on transdermal or dermal delivery has been limited by these requirements. In recent years various passive and active strategies have emerged to optimize delivery. The passive approach entails the optimization of formulation or drug carrying vehicle to increase skin permeability. However, passive methods do not greatly improve the permeation of drugs with molecular weights >500 Da. In contrast, active methods, normally involving physical or mechanical methods of enhancing delivery, have been shown to be generally superior. The delivery of drugs of differing lipophilicity and molecular weight, including proteins, peptides and oligonucletides, has been shown to be improved by active methods such as iontophoresis, electroporation, mechanical perturbation and other energy-related techniques such as ultrasound and needleless injection. This chapter details one practical example of an active skin abrasion device to demonstrate the success of such active methods. The in vitro permeation of acyclovir through human epidermal membrane using a rotating brush abrasion device was compared with acyclovir delivery using iontophoresis. It was found that application of brush treatment for 10 s at a pressure of 300 N m(-2) was comparable to 10 min of iontophoresis. The observed enhancement of permeability observed using the rotating brush was a result of disruption of the cells of the stratum corneum, causing a reduction of the barrier function of the skin. However, for these novel delivery methods to succeed and compete with those already on the market, the prime issues that require consideration include device design and safety, efficacy, ease of handling, and cost-effectiveness. This chapter provides a detailed review of the next generation of active delivery technologies.

Modeling the economic and health consequences of managing chronic osteoarthritis pain with opioids in Germany: comparison of extended-release oxycodone and OROS hydromorphone

OBJECTIVE

The Osmotic controlled-Release Oral delivery System (OROS) hydromorphone ensures continuous release of hydromorphone over 24 hours. It is anticipated that this will facilitate optimal pain relief, improve quality of sleep and compliance. This simulation compared managing chronic osteoarthritis pain with once-daily OROS hydromorphone with an equianalgesic dose of extended-release (ER) oxycodone administered two or three times a day.

METHODS

This discrete event simulation follows patients for a year after initiating opioid treatment. Pairs of identical patients are created; one receives OROS hydromorphone the other ER oxycodone; undergo dose adjustments and after titration can be dissatisfied or satisfied, suffer adverse events, pain recurrence, or discontinue the opioid. Each is assigned an initial sleep problems score, and an improved score from a treatment dependent distribution at the end of titration; these are translated to a utility value. Utilities are assigned pre-treatment, updated until the patient reaches the optimal dose or is non-compliant or dissatisfied. The OROS hydromorphone and ER oxycodone doses are converted to equianalgesic morphine doses using the following ratios: hydromorphone to morphine ratio; 1:5, oxycodone to morphine ratio; 1:2. Sensitivity analyses explored uncertainty in the conversion ratios and other key parameters. Direct medical costs are in 2005 euros.

RESULTS

Over 1 year on a mean daily morphine-equivalent dose of 90 mg, 14% were estimated to be dissatisfied with each opioid. OROS hydromorphone was predicted to yield 0.017 additional quality-adjusted life years (QALYs)/patient for a small additional annual cost (E141/patient), yielding an incremental cost-effectiveness ratio (ICER) of E8343/QALY gained. Changing the assumed conversion ratio for oxycodone:morphine to 1:1.5 led to lower net costs of E68 per patient, E3979/QALY, and for hydromorphone to 1:7.5 to savings.

CONCLUSION

Based on these analyses, OROS hydromorphone is expected to yield health benefits at reasonable cost in Germany.

Topical agents for the management of musculoskeletal pain

The recent recognition of the magnitude of cardiovascular risk of both nonselective nonsteroidal anti-inflammatory drugs and COX-2 selective inhibitors, in addition to the persistent concerns about the use of opioids, has brought increased attention to nonsystemic, topical analgesics. These agents have a favorable safety profile and there is increasing evidence indicating their efficacy for a variety of pain disorders. The use of topical analgesics in the treatment of the most prevalent musculoskeletal pain syndromes is described, with a focus on mechanisms for drug delivery and clinical trials data.

Economic evaluation of Durogesic in moderate to severe, nonmalignant, chronic pain in Germany

We carried out a cost-effectiveness evaluation of transdermal fentanyl compared to three other widely used opioids: transdermal buprenorphine, sustained-release morphine, and controlled-release oxycodone from a third-party-payers perspective. A decision analytic model with data from a structured database search and from panel data and assumptions was used to derive both cost and utility results. Probabilistic sensitivity analysis was performed to ensure the findings. Transdermal fentanyl patients gain more quality adjusted life-days or quality-adjusted life-years per euro. The incremental cost per quality-adjusted life-year is 1,625.65 euro for transdermal fentanyl compared to sustained-release morphine and 1,003.03 euro compared to CO, and it is cost-saving compared to transdermal buprenorphine (-203.38 euro per patient). Transdermal fentanyl is thus cost-effective compared to both sustained-release morphine and CO and dominant compared to transdermal buprenorphine in the treatment of adults with nonmalignant moderate to severe chronic pain.

Endogenous opiates and behavior: 2003

This paper is the 26th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over a quarter-century of research. It summarizes papers published during 2003 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).