Cost-effectiveness analysis of oxycodone with naloxone versus oxycodone alone for the management of moderate-to-severe pain in patients with opioid-induced constipation in Canada

Efficacy and Safety of Peripherally Acting Mu-Opioid Receptor Antagonists for the Treatment of Opioid-Induced Constipation: A Bayesian Network Meta-analysis

OBJECTIVE

To assess the efficacy and safety of peripherally acting mu-opioid receptor antagonists (PAMORAs) for the treatment of opioid-induced constipation (OIC).

METHODS

Randomized controlled trials (RCTs) were searched for OIC therapy comparing PAMORAs with placebo. Both a pairwise and network meta-analysis were performed. The surface under the cumulative ranking area (SUCRA) was used to determine the efficacy and safety of OIC treatment using different PAMORAs.

RESULTS

The primary target outcome was a response that achieves an average of three or more bowel movements (BMs) per week. In the network meta-analysis, four PAMORAs (naldemedine, naloxone, methylnaltrexone, and alvimopan) showed a better BM response than the placebo. Naldemedine was ranked first (odds ratio [OR] = 2.8, 95% credible interval [CrI] = 2-4.5, SUCRA = 89.42%), followed by naloxone (OR = 2.9, 95% CrI = 1.6-5.3, SUCRA = 87.44%), alvimopan (OR = 2.2, 95% CrI = 1.3-3.5, SUCRA = 68.02%), and methylnaltrexone (OR = 1.7, 95% CrI = 1.0-2.8, SUCRA = 46.09%). There were no significant differences in safety found between the PAMORAs and the placebo.

CONCLUSIONS

We found that PAMORAs are effective and can be safely used for the treatment of OIC. In network meta-analysis, naldemedine and naloxone appear to be the most effective PAMORAs for the treatment of OIC.

Oxycodone versus morphine for cancer pain titration: A systematic review and pharmacoeconomic evaluation

Objective

To evaluate the efficacy, safety and cost-effectiveness of Oxycodone Hydrochloride Controlled-release Tablets (CR oxycodone) and Morphine Sulfate Sustained-release Tablets (SR morphine) for moderate to severe cancer pain titration.

Methods

Randomized controlled trials meeting the inclusion criteria were searched through Medline, Cochrane Library, Pubmed, EMbase, CNKI,VIP and WanFang database from the data of their establishment to June 2019. The efficacy and safety data were extracted from the included literature. The pain control rate was calculated to eatimate efficacy. Meta-analysis was conducted by Revman5.1.4. A decision tree model was built to simulate cancer pain titration process. The initial dose of CR oxycodone and SR morphine group were 20mg and 30mg respectively. Oral immediate-release morphine was administered to treat break-out pain. The incremental cost-effectiveness ratio was performed with TreeAge Pro 2019.

Results

19 studies (1680 patients)were included in this study. Meta-analysis showed that the pain control rate of CR oxycodone and SR morphine were 86% and 82.98% respectively. The costs of CR oxycodone and SR morphine were $23.27 and $13.31. The incremental cost-effectiveness ratio per unit was approximate $329.76. At the willingness-to-pay threshold of $8836, CR oxycodone was cost-effective, while the corresponding probability of being cost-effective at the willingness-to-pay threshold of $300 was 31.6%. One-way sensitivity analysis confirmed robustness of results.

Conclusions

CR oxycodone could be a cost-effective option compared with SR morphine for moderate to severe cancer pain titration in China, according to the threshold defined by the WHO.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

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.

Efficacy of pharmacological therapies for the treatment of opioid-induced constipation: systematic review and network meta-analysis

OBJECTIVE

Opioids are increasingly prescribed in the West and have deleterious GI consequences. Pharmacological therapies to treat opioid-induced constipation (OIC) are available, but their relative efficacy is unclear. We performed a systematic review and network meta-analysis to address this deficit in current knowledge.

DESIGN

We searched MEDLINE, EMBASE, EMBASE Classic and the Cochrane central register of controlled trials through to December 2017 to identify randomised controlled trials (RCTs) of pharmacological therapies in the treatment of adults with OIC. Trials had to report a dichotomous assessment of overall response to therapy, and data were pooled using a random effects model. Efficacy and safety of pharmacological therapies was reported as a pooled relative risk (RR) with 95% CIs to summarise the effect of each comparison tested and ranked treatments according to their P-score.

RESULTS

Twenty-seven eligible RCTs of pharmacological therapies, containing 9149 patients, were identified. In our primary analysis, using failure to achieve an average of ≥3 bowel movements (BMs) per week with an increase of ≥1 BM per week over baseline or an average of ≥3 BMs per week, to define non-response, the network meta-analysis ranked naloxone first in terms of efficacy (RR=0.65; 95% CI 0.52 to 0.80, P-score=0.84), and it was also the safest drug. When non-response to therapy was defined using failure to achieve an average of ≥3 BMs per week, with an increase of ≥1 BM per week over baseline, naldemedinewas ranked first (RR=0.66; 95% CI 0.56 to 0.77, P score=0.91) and alvimopan second (RR=0.74; 95% CI 0.57 to 0.94, P-score=0.71).

CONCLUSION

In network meta-analysis, naloxone and naldemedine appear to be the most efficacious treatments for OIC. Naloxone was the safest of these agents.

The role of oxycodone/naloxone in the management of patients with pain and opioid-induced constipation

INTRODUCTION

Common opioid adverse effects (AE) of the gastrointestinal tract include opioid-induced constipation (OIC) and opioid-induced bowel dysfunction (OIBD) with traditional laxatives being of limited efficacy, having AEs and not addressing the pathophysiology of OIC or OIBD. Targeted treatment comprises of PAMORA (peripherally acting mu-opioid receptor antagonists) and a combination of an opioid receptor agonist with its antagonist, namely prolonged-release oxycodone with prolonged-release naloxone (OXN) tablets at a fixed ratio of 2:1. Oxycodone provides analgesia, whereas naloxone prevents binding or displaces it from opioid receptors located in the gut wall. Areas covered: The authors review the role of OXN in the management of patients with pain and OIC. A literature search was performed using the search terms 'oxycodone/naloxone' and 'opioid-induced constipation' using the PubMed database up to October 2018. Expert opinion: OXN delivers analgesia comparable (or superior versus placebo and in observational studies) to oxycodone alone and other opioids with a limited or decreased disturbing effect on bowel function. OXN in daily doses of up to 160 mg/80 mg provides effective analgesia with little negative impact on bowel function. OXN may be successfully used in patients with chronic pain, to prevent or treat symptoms of OIC and OIBD.

Peripherally acting μ-opioid receptor antagonists as treatment options for constipation in noncancer pain patients on chronic opioid therapy

Opioid-induced constipation (OIC), a prevalent and distressing side effect of opioid therapy, does not reliably respond to treatment with conventional laxatives. OIC can be a treatment-limiting adverse event. Recent advances in medications with peripherally acting μ-opioid receptor antagonists, such as methylnaltrexone, naloxegol, and alvimopan, hold promise for treating OIC and thus extending the benefits of opioid analgesia to more chronic pain patients. Peripherally acting μ-opioid receptor antagonists have been clinically tested to improve bowel symptoms without compromise to pain relief, although there are associated side effects, including abdominal pain. Other treatment options include fixed-dose combination products of oxycodone analgesic together with naloxone.

Treatment of Severe Pain and Opioid-induced Constipation: An Observational Study of Quality of Life, Resource Use, and Costs in Sweden

INTRODUCTION

Opioid-induced constipation (OIC) is a common and costly side effect of opioid treatment affecting patients' quality of life (QoL). The combination oxycodone/naloxone reduces OIC while providing effective analgesia in patients with moderate to severe pain. The objective of this observational study was to compare health-related quality of life (HRQoL), healthcare resource use, and costs in patients with severe pain who were initially treated with oxycodone and laxatives and then subsequently switched to treatment with oxycodone/naloxone.

METHODS

Data were collected by means of questionnaires completed by patients with OIC before and after the initiation of oxycodone/naloxone treatment at different clinical centers in Sweden. The questionnaires included questions on healthcare resource use and absence from work and also consisted of the Patient Assessment of Constipation-QoL (PAC-QoL) instrument, the EuroQol five dimensions questionnaire (EQ-5D), the Patient Assessment of Constipation Symptoms (PAC-SYM) instrument, and the Bowel Function Index (BFI).

RESULTS

The analysis included 37 patients. Resource utilization was lower after treatment with oxycodone/naloxone, in terms of both the number of healthcare contacts and the purchases of medicine for the treatment of constipation. According to the BFI score, patients had fewer problems with OIC after the initiation of oxycodone/naloxone. The PAC-QoL score showed a positive change for patients in both the 96-point dissatisfaction index and the 16-point satisfaction index. PAC-SYM scores was lower after the initiation of oxycodone/naloxone treatment, indicating fewer constipation-related problems.

CONCLUSION

Treatment with oxycodone/naloxone had an overall positive effect on patients, consisting mainly of decreasing the severity of the constipation problems, increasing HRQoL, and decreasing the use of healthcare resources.

FUNDING

Mundipharma AB, Gothenburg, Sweden.