Pharmacological prevention and treatment of opioid-induced constipation in cancer patients: A systematic review and meta-analysis

BACKGROUND

Cancer-related pain often requires opioid treatment with opioid-induced constipation (OIC) as its most frequent gastrointestinal side-effect. Both for prevention and treatment of OIC osmotic (e.g. polyethylene glycol) and stimulant (e.g. bisacodyl) laxatives are widely used. Newer drugs such as the peripherally acting µ-opioid receptor antagonists (PAMORAs) and naloxone in a fixed combination with oxycodone have become available for the management of OIC. This systematic review and meta-analysis aims to give an overview of the scientific evidence on pharmacological strategies for the prevention and treatment of OIC in cancer patients.

METHODS

A systematic search in PubMed, Embase, Web of Science and the Cochrane Library was completed from inception up to 22 October 2022. Randomized and non-randomized studies were systematically selected. Bowel function and adverse drug events were assessed.

RESULTS

Twenty trials (prevention: five RCTs and three cohort studies; treatment: ten RCTs and two comparative cohort studies) were included in the review. Regarding the prevention of OIC, three RCTs compared laxatives with other laxatives, finding no clear differences in effectivity of the laxatives used. One cohort study showed a significant benefit of magnesium oxide compared with no laxative. One RCT found a significant benefit for the PAMORA naldemedine compared with magnesium oxide. Preventive use of oxycodone/naloxone did not show a significant difference in two out of three other studies compared to oxycodone or fentanyl. A meta-analysis was not possible. Regarding the treatment of OIC, two RCTs compared laxatives, of which one RCT found that polyethylene glycol was significantly more effective than sennosides. Seven studies compared an opioid antagonist (naloxone, methylnaltrexone or naldemedine) with placebo and three studies compared different dosages of opioid antagonists. These studies with opioid antagonists were used for the meta-analysis. Oxycodone/naloxone showed a significant improvement in Bowel Function Index compared to oxycodone with laxatives (MD -13.68; 95 % CI -18.38 to -8.98; I2 = 58 %). Adverse drug event rates were similar amongst both groups, except for nausea in favour of oxycodone/naloxone (RR 0.51; 95 % CI 0.31-0.83; I2 = 0 %). Naldemedine (NAL) and methylnaltrexone (MNTX) demonstrated significantly higher response rates compared to placebo (NAL: RR 2.07, 95 % CI 1.64-2.61, I2 = 0 %; MNTX: RR 3.83, 95 % CI 2.81-5.22, I2 = 0 %). With regard to adverse events, abdominal pain was more present in treatment with methylnaltrexone and diarrhea was significantly more present in treatment with naldemedine. Different dosages of methylnaltrexone were not significantly different with regard to both efficacy and adverse drug event rates.

CONCLUSIONS

Magnesium oxide and naldemedine are most likely effective for prevention of OIC in cancer patients. Naloxone in a fixed combination with oxycodone, naldemedine and methylnaltrexone effectively treat OIC in cancer patients with acceptable adverse events. However, their effect has not been compared to standard (osmotic and stimulant) laxatives. More studies comparing standard laxatives with each other and with opioid antagonists are necessary before recommendations for clinical practice can be made.

Effect of oral naloxone on opioid-induced constipation in methadone maintenance treatment patients, a double-blind, placebo-control, clinical trial

BACKGROUND

Opioid-induced constipation (OIC) is the most prevalent side effect of methadone maintenance therapy (MMT). Naloxone could reduce the OIC.

METHOD

Fifty-six MMT cases (< 75 mg/day methadone, > 3 months) were entered randomly into four groups of a trial. They received placebo or naloxone tablets (0.5, 2, or 4 mg/day) once a day for 2 weeks. They continued their conventional laxative. Their constipation and opiate withdrawal (OWS) were evaluated by the Bristol Stool Form Scale (stool consistency and frequency), Patient Assessment of Constipation Symptoms (PAC-SYM) questionnaire, Constipation Scoring System (CSS), and the Subjective Opiate Withdrawal Scale (SOWS) before starting treatment and at the end of the first and second weeks.

RESULTS

The dose of 4 mg/day naloxone was excluded from the study due to severe OWS. The precipitants of groups had similar ages, methadone dose and duration, laxative use, and constipation scores at the start of the trial. However, 2 mg of naloxone could change the stool consistency (PV = 0.0052) and frequency (P = 0.0133), 0.5 mg/day dose only improved the stool consistency (P = 0.0016). The patients' CSS and PAC-SYM scores were reduced by naloxone after the 1st week of treatment. However, there was no significant difference in the mean score of SOWS at different assessment times and groups. Also, 3 and 4 cases of 0.5 and 2 mg/day groups, respectively, withdrew from the study due to OWS.

CONCLUSION

Oral naloxone at doses of 0.5 and 2 mg/day was significantly more effective than placebo on OIC in MMT. However, the dose of 4 mg induced intolerable OWS.

Total postoperative opioid dose is an independent risk factor for prolonged postoperative ileus after laparoscopic colorectal surgery: a case-control study

BACKGROUND

Prolonged postoperative ileus (PPOI) is a major complication of colorectal surgery. Increased opioid consumption has been proposed to increase the risk of PPOI. This study aimed to test the hypothesis that an increased total postoperative opioid dose (TPOD) is associated with the increased incidence of PPOI.

METHODS

For this matched case-control study, patients who underwent elective laparoscopic colorectal procedures at the Peking University People's Hospital between January 2018 and June 2020 were retrospectively reviewed. Patients with PPOI were assigned to the ileus group, while patients without PPOI (control group) were matched at a 1:1 ratio to the ileus group according to age, American Society of Anesthesiologists physical status score, and type of surgical procedure. The primary outcome was the TPOD between the ileus and control groups. The secondary outcome was risk factors of PPOI.

RESULTS

A total of 267 participants were included in the final analysis. No differences in baseline or operative factors were found between the two groups. The TPOD, intravenous sufentanil dose on postoperative day 1 (POD1), and the use of patient-controlled analgesia with basal infusion were associated with PPOI (P < 0.05). Multivariate logistic regression analysis revealed that an increased TPOD was an independent risk factor for developing PPOI after laparoscopic colorectal procedures (Odd ratio: 1.67, 95% CI [1.03, 2.71], P = 0.04).

CONCLUSIONS

The TPOD is an independent risk factor for PPOI after laparoscopic colorectal surgery. We need to explore new strategies of postoperative analgesia to reduce the dosage of TPOD.

Overcoming barriers to opioid-induced constipation management in cancer patients

PURPOSE

Opioid-induced constipation (OIC) is a common adverse effect of opioid therapy. We aim to identify the main barriers hindering clinical recommendations implementation and propose consensus solutions to improve OIC control in cancer patients.

METHODS

Following collaborative and prioritization techniques, a scientific committee generated statements addressing possible barriers to optimal OIC management (related to patients, health providers and health care system), and potential interventions to overcome these barriers. An expert panel of 36 oncologists assessed the statements to reach a consensus.

RESULTS

The survey consisted of 70 statements. Consensus was reached on 12/45 items related to barriers (26.6%) and on 19/25 items about corrective interventions (76%). The panel considered that patients are unaware of the existence of a specific OIC treatment, and their information sources are highly variable and unreliable. Regarding health providers, the panel considered that the oncologists prioritize symptoms such as diarrhea, pain, anxiety, or other treatment toxicities, over constipation. Work overload and bureaucratic requirements were the main barriers related to health care system. Regarding potential interventions, best-rated proposals included specific training programs development for primary care physicians and nurses, and multiplatform informative resources development for patients and caregivers, including precisely written instructions about OIC recognition and management. Oncologists assessed positively measures aiming to improve coordination between primary care physicians and oncologists, and nursing consultations implementation. The panel considered useful the OIC treatment algorithms simplification.

CONCLUSIONS

The expert panel identified the main barriers to optimal OIC management and suggested some feasible approaches to overcome these barriers.

A Nationwide Hospital Claims Database Analysis of Real-World Patterns of Laxative Use for Opioid-Induced Constipation in Japanese Patients with Cancer

INTRODUCTION

Opioid-induced constipation (OIC) is one of the most common side effects in patients with cancer treated with opioid analgesics. The actual use of laxatives for OIC in Japan remains unelucidated. This study aimed to investigate the real-world patterns of laxative use for patients with cancer who newly initiated opioid analgesic therapy.

METHODS

We used a Japanese nationwide hospital claims database (January 2018-December 2019). Patients with cancer newly receiving opioid analgesic therapy were included and classified on the basis of opioid classes (weak or strong) and route of administration (oral or transdermal) at initiation. The patients were divided into two groups on the basis of whether they received early medication (starting laxatives within 3 days after initiating opioid analgesic therapy), and patterns of laxative use were analyzed.

RESULTS

There were 26,939 eligible patients, with 50.7% of them initiated with strong opioids. The proportion of patients who received early medication was 25.0% for weak opioids and 57.3% for strong opioids. Osmotic laxatives were most frequently used as first-line therapy in the early medication group (oral weak opioids: 12.3%, oral strong opioids: 29.4%, transdermal strong opioids: 12.8%). Stimulant laxatives were frequently used as first-line therapy, to the same extent or more than osmotic laxatives in the non-early medication group (oral weak opioids: 13.7%, oral strong opioids: 7.7%, transdermal strong opioids: 15.1%). Peripherally acting μ-opioid receptor antagonists were the second most frequently used in the early medication group for those on oral strong opioids (9.4%).

CONCLUSION

This study demonstrated for the first time that the patterns of laxative use for OIC in Japanese patients with cancer were different, depending on the opioid types at initiation and the timing of laxative medication.

Opioid withdrawal syndrome developing after long-term administration of naldemedine

OBJECTIVE

One of the side effects of opioid administration is opioid-induced constipation (OIC). To address this side effect, the oral peripheral μ opioid receptor antagonist naldemedine was developed. As this drug does not cross the blood-brain barrier, it is thought that it does not lead to opioid withdrawal syndrome (OWS) with central nervous system symptoms.

METHODS

Here, we report a cancer patient who presented with symptoms centered round anxiety and irritation 4 months after administration of naldemedine for OIC and who was diagnosed with OWS after close investigation.

RESULTS

The patient was a 65-year-old female who had surgery for stage IB endometrial cancer 4 years previously, but experienced recurrence involving the pelvis 2 years later. Medical narcotics were used to control pain, but naldemedine was started to control subsequent constipation. When naldemedine-related OWS was suspected and the administration of naldemedine discontinued, the above symptoms disappeared within two days, and no recurrence was observed thereafter.

SIGNIFICANCE OF THE RESULTS

For patients receiving naldemedine, it is necessary to consider the possibility of OWS regardless of the period of administration in order to maintain patient quality of life.

Opioid-Induced Constipation in Real-World Practice: A Physician Survey, 1 Year Later

INTRODUCTION

Opioid-induced constipation (OIC) is the most common adverse effect of opioid therapy, but it is underdiagnosed and undertreated. Last year, a survey among Italian healthcare providers revealed important differences in the clinical management of OIC across physician specialties, the need of standardization of diagnosis and treatment, and the urgency of further education. Herein, we submitted an updated version of the survey to the same cohort of experts to evaluate potential progress.

METHODS

The online survey included 15 questions about OIC. Responses were analyzed descriptively and aggregated by physician specialty.

RESULTS

A total of 190 physicians completed the survey. Most respondents (65%) did not feel adequately educated about OIC despite general consensus regarding interest in the topic and acknowledgement of OIC impact on patients' QoL and adherence to opioid therapy. Overall, 55-77% of physicians regularly evaluated intestinal function or OIC symptoms in patients receiving opioid therapy, with one-third of respondents implementing it in the past year. Even though the most common method for assessment was still patient diary, the use of specific scales underwent a small but significant increase compared to the previous year, with major implementation in the use of Rome IV criteria. As regards first-line treatment, most respondents (49%) preferred macrogol prophylaxis followed by macrogol plus another laxative. For second-line treatment, we revealed a growth in the prescription of peripherally acting mu-opioid receptor antagonists (PAMORAs), with 46% of all the respondents having increased their use during the past year.

CONCLUSIONS

Despite some limitations, our study demonstrated a slow but important step closer to standardization of diagnosis and treatment of OIC. Further educational and training efforts should be put in place to favor best evidence-based clinical practice.

Opioid-Induced Constipation: Cost Impact of Approved Medications in the Emergency Department

INTRODUCTION

Opioid-induced constipation (OIC) prescription medications (OIC-Rx) like methylnaltrexone subcutaneous (SC) have shown efficacy in treating OIC in the emergency department (ED). This study aimed to describe and compare healthcare resource utilization (HRU) and healthcare costs in ED patients with OIC receiving OIC-Rx versus those not receiving OIC-Rx.

METHODS

Adult patients with OIC during an ED encounter were identified from a hospital-based ED encounters database (2016-2019) and classified on the basis of receipt of OIC-Rx (OIC-Rx versus No OIC-Rx cohorts). Entropy balancing was used to reweight characteristics of the two cohorts. HRU and healthcare costs were measured and compared during the ED encounter and 30-day post-discharge period.

RESULTS

Among 11,135 patients in the OIC-Rx cohort (21,474 in the No OIC-Rx cohort), 93% received methylnaltrexone SC. Patients in the OIC-Rx cohort had 0.7 fewer inpatient days per OIC ED encounter and 64% decreased odds of being hospitalized versus the No OIC-Rx cohort (both p < 0.001). During the post-discharge period, the OIC-Rx cohort had 35% decreased odds of any re-encounter (p < 0.001). The OIC-Rx cohort had a $732 reduction in costs per OIC ED encounter versus the No OIC-Rx cohort (p < 0.001), driven by larger hospitals and patients with Medicare or Commercial insurance. During the post-discharge period, the OIC-Rx cohort had a $421 reduction in costs associated with any re-encounter versus the No OIC-Rx cohort (p = 0.004).

CONCLUSION

Patients receiving OIC-Rx in the ED had decreased odds of being hospitalized and fewer re-encounters in the 30-day post-discharge period versus patients who did not receive OIC-Rx, resulting in cost savings for insurance agencies and healthcare providers.

Impact and Consequences of Opioid-Induced Constipation: A Survey of Patients

INTRODUCTION

Opioids are a valuable tool to help achieve control of pain. However, opioid-induced constipation (OIC) is an important limitation of treatment with this class of drugs.

METHODS

To better understand the impact of OIC on patient-reported outcomes, we carried out a survey involving patients being treated with opioids. Both ad hoc questions and the PROMIS and PAC-SYM and PAC-QOL scores were used.

RESULTS

Of the 597 participants, 150 (25%) had cancer-related pain, and 447 (75%) had non-cancer pain; 66% experienced OIC. PROMIS pain interference questions indicated that pain is more likely to interfere with a patient's life when they have OIC. PAC-QOL and PAC-SYM revealed that 58% of patients with non-cancer pain and OIC reported at least one "severe" or "very severe" constipation symptom, compared to 83% with cancer-related pain. Younger age and less time on opioids were associated with greater impact of OIC on quality of life. Only 41% of patients were satisfied with how their constipation was managed. Over 50% of those with non-cancer pain said that they modified their opioid regimen due to constipation, vs. 6% of those with cancer pain. Constipation had been discussed with the healthcare provider (HCP) in 48% of non-cancer patients and in 73% of cancer patients. In those with chronic pain and OIC, 24% expressed varying degrees of dissatisfaction with the healthcare system, vs. 37% in those with cancer pain and OIC.

CONCLUSION

Our results provide additional evidence that management of OIC is inadequate in many cases. Moreover, they indicate that there is a definite need for better education about OIC among HCPs.

Management of Opioid-Induced Constipation and Bowel Dysfunction: Expert Opinion of an Italian Multidisciplinary Panel

The prescribing and use of opioid analgesics is increasing in Italy owing to a profusion in the number and types of opioid analgesic products available, and the increasing prevalence of conditions associated with severe pain, the latter being related to population aging. Herein we provide the expert opinion of an Italian multidisciplinary panel on the management of opioid-induced constipation (OIC) and bowel dysfunction. OIC and opioid-induced bowel dysfunction are well-recognised unwanted effects of treatment with opioid analgesics that can profoundly affect quality of life. OIC can be due to additional factors such as reduced mobility, a low-fibre diet, comorbidities, and concomitant medications. Fixed-dose combinations of opioids with mu (μ) opioid receptor antagonists, such as oxycodone/naloxone, have become available, but have limited utility in clinical practice because the individual components cannot be independently titrated, creating a risk of breakthrough pain as the dose is increased. A comprehensive prevention and management strategy for OIC should include interventions that aim to improve fibre and fluid intake, increase mobility or exercise, and restore bowel function without compromising pain control. Recommended first-line pharmacological treatment of OIC is with an osmotic laxative (preferably polyethylene glycol [macrogol]), or a stimulant laxative such as an anthraquinone. A second laxative with a complementary mechanism of action should be added in the event of an inadequate response. Second-line treatment with a peripherally acting μ opioid receptor antagonist (PAMORA), such as methylnaltrexone, naloxegol or naldemedine, should be considered in patients with OIC that has not responded to combination laxative treatment. Prokinetics or intestinal secretagogues, such as lubiprostone, may be appropriate in the third-line setting, but their use in OIC is off-label in Italy, and should therefore be restricted to settings such as specialist centres and clinical trials.

Insights into the Use of Peripherally Acting μ-Opioid Receptor Antagonists (PAMORAs) in Oncologic Patients: from Scientific Evidence to Real Clinical Practice

OPINION STATEMENT

Management of chronic pain is crucial to improve the quality of life of cancer and palliative care patients. Opioid-based treatments used to control pain can be prolonged over time. Unfortunately, constipation is one of the most disturbing adverse effects of long-term use of opioids. Opioid-induced constipation (OIC) occurs when opioids bind to the specific receptors present in the gastrointestinal (GI) tract, and can affect any patients receiving chronic opioid therapy, including cancer patients. The limited efficacy of laxatives to treat OIC symptoms prompted the search for new therapeutic strategies. Peripherally acting μ-opioid receptor antagonists (PAMORAs) have recently emerged as new effective drugs for OIC management due to their specific binding to enteric μ-receptors. Little information is available on the use of PAMORAs in real-life practice for OIC treatment in cancer patients. In this paper, a panel of experts specializing in cancer and palliative care pools their clinical experience with PAMORAs in cancer patients presenting OIC and highlights the importance of timing and choice of therapy in achieving prompt OIC management and benefitting patients.

Efficacy and Safety of Methylnaltrexone for the Treatment of Opioid-Induced Constipation: A Meta-analysis of Randomized Controlled Trials

Introduction

Opioid-induced constipation (OIC) is a distressing side effect during opioid analgesia and is mainly mediated by gastrointestinal μ-opioid receptors. Methylnaltrexone, a peripheral μ-opioid receptor antagonist with restricted ability to cross the blood–brain barrier, may alleviate OIC without reversing analgesia. We performed a meta-analysis to assess the efficacy and safety of methylnaltrexone for the treatment of OIC.

Methods

This meta-analysis was registered in PROSPERO (CRD42020187290). We searched PubMed, Embase, and Cochrane Library for randomized controlled trials that compared methylnaltrexone with placebo for the treatment of OIC. Relative risks (RR) and 95% confidence interval (CI) were pooled using a random-effects model. We used the GRADE approach to assess the certainty of the evidence.

Results

Eight trials with 2034 participants were included. Compared with placebo, methylnaltrexone significantly increased rescue-free bowel movement (RFBM) within 4 h after the first dose (eight trials; 1833 participants; RR 3.74, 95% CI 3.02–4.62; high-certainty evidence), RFBM within 24 h after the first dose (two trials; 614 participants; RR 1.98, 95% CI 1.52–2.58; moderate-certainty evidence), and RFBM ≥ 3 times per week (three trials; 1,396 participants; RR 1.33, 95% CI 1.17–1.52; moderate-certainty evidence) and decreased need to take rescue laxatives (three trials; 807 participants; RR 0.73, 95% CI 0.63–0.85; moderate-certainty evidence). For safety outcomes, there was no difference in any adverse events between the two groups (eight trials; 2034 participants; RR 1.11, 95% CI 0.99–1.23; moderate-certainty evidence), including diarrhea, nausea, vomiting, and flatulence; but for the most commonly reported adverse events, the abdominal pain was higher in methylnaltrexone group than that in placebo group (six trials; 1813 participants; RR 2.30, 95% CI 1.29–4.08; moderate-certainty evidence).

Conclusion

Methylnaltrexone is an effective and safe drug for the treatment of OIC, but the safety of abdominal pain should be considered.

Opioid therapy duration before naldemedine treatment is a significant independent risk of diarrhea: a retrospective cohort study

Background

The most common adverse event (AE) associated with opioid analgesics is opioid-induced constipation (OIC). Naldemedine (NAL) is widely used for the treatment of OIC. However, diarrhea has been reported as the most common treatment-emergent AE of NAL, and little is known about the risk factors associated with the development of diarrhea during NAL administration. This study examined the risk factors for NAL-induced diarrhea via a retrospective chart review of hospitalized patients.

Methods

The data of 101 hospitalized adult patients who received NAL for the first time for the treatment of OIC at Mie University Hospital between June 2017 and December 2018 were extracted from electronic medical records. According to the inclusion and exclusion criteria, 70 of the 101 patients were enrolled in this study. Diarrhea was defined as “diarrhea” on the medical record within 2 weeks of NAL administration. Univariate and multivariate analyses were performed to identify risk factors for the development of diarrhea in patients receiving NAL.

Results

Twenty-two of the 70 patients enrolled (31%) developed diarrhea within 2 weeks of NAL administration. The median duration (range) of NAL treatment before diarrhea onset was 3 (1–12) days. Patients with diarrhea had a significantly longer duration of opioid therapy before NAL administration than patients without diarrhea (P=0.002). Multivariate logistic regression analysis indicated that the independent risk factors for the development of NAL-induced diarrhea were NAL administration after more than 17 days of opioid therapy (odds ratio [OR]=7.539; P=0.016) and pancreatic cancer (OR=6.217; P=0.025). In fact, the incidence of diarrhea in patients who were administered NAL within a day of opioid therapy was significantly lower than that in patients who were administered NAL after more than 17 days of opioid therapy (13% vs. 54%, P=0.030).

Conclusions

These results suggested that a prolonged duration of opioid therapy prior to NAL initiation is associated with increased incidence of diarrhea.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40780-020-00187-3.

Peripherally Acting μ-Opioid Receptor Antagonists in the Management of Postoperative Ileus: a Clinical Review

Postoperative ileus (POI) and constipation are common secondary effects of opioids and carry significant clinical and economic impacts. μ-Opioid receptors mediate opioid analgesia in the central nervous system (CNS) and gastrointestinal-related effects in the periphery. Peripherally acting μ-opioid receptor antagonists (PAMORAs) block the peripheral effects of opioids in the gastrointestinal tract, while maintaining opioid analgesia in the CNS. While most are not approved for POI or postoperative opioid-induced constipation (OIC), PAMORAs have a potential role in these settings via their selective effects on the μ-opioid receptor. This review will discuss recent clinical trials evaluating the safety and efficacy of PAMORAs, with a focus on alvimopan (Entereg^®) and methylnaltrexone (Relistor^®) in patients with POI or postoperative OIC. We will characterize potential factors that may have impacted the efficacy observed in phase 3 trials and discuss future directions for the management and treatment of POI.

Opioid-induced constipation in patients with cancer pain in Japan (OIC-J study): a post hoc subgroup analysis of patients with gastrointestinal cancer

BACKGROUND

Constipation is a common side effect of opioid therapy. An observational study of opioid-induced constipation (OIC) in Japanese patients with cancer (OIC-J) included 212 patients with various tumor types. This post hoc analysis of OIC-J evaluated a subgroup of patients with gastrointestinal (GI) cancer.

METHODS

Patients were aged ≥ 20 years, starting strong opioid therapy, had an ECOG PS of ≤ 2, and must have had ≥ 3 bowel movements during the week before enrollment. OIC was evaluated for 2 weeks after opioid initiation using the Rome IV diagnostic criteria for colorectal disorders, as well as physician's diagnosis, number of spontaneous bowel movements, Bowel Function Index score, and patient's self-assessment. Relationships between baseline characteristics and OIC incidence, and the effects of OIC on quality of life (QOL) were also explored.

RESULTS

Fifty patients from OIC-J who had GI cancer [colon (50%), stomach (28%), and esophageal (22%)] were included. OIC incidence varied by which diagnostic criteria were used (46.0-62.0%) and occurred rapidly after initiating opioid therapy. The use of prophylactic laxatives reduced the overall incidence rate of OIC from 71.0% to 47.4%. No baseline characteristics, except comorbidities, were associated with OIC incidence. Change from baseline to day 15 in PAC-SYM total score was significantly greater for patients with OIC versus those without OIC (0.188 versus -0.362; P = 0.0011).

CONCLUSIONS

This post hoc analysis suggests that OIC occurs rapidly in patients with GI cancer after initiating opioid therapy, and negatively impacts QOL. Early and effective intervention strategies may be particularly useful in this group.

ADDITIONAL INFORMATION

Coauthor Makio Gamoh is deceased.

What to Do and What Not to Do in the Management of Opioid-Induced Constipation: A Choosing Wisely Report

Introduction

Despite the essential utility of opioids for the clinical management of pain, opioid-induced constipation (OIC) remains an important obstacle in clinical practice. In patients, OIC hinders treatment compliance and has negative effects on quality of life. From a clinician perspective, the diagnosis and management of OIC are hampered by the absence of a clear, universal diagnostic definition across disciplines and a lack of standardization in OIC treatment and assessment.

Methods

A multidisciplinary panel of physician experts who treat OIC was assembled to identify a list of ten corrective actions—five “things to do” and five “things not to do”—for the diagnosis and management of OIC, utilizing the Choosing Wisely methodology.

Results

The final list of corrective actions to improve the diagnosis and clinical management of OIC emphasized a need for: (i) better physician and patient education regarding OIC; (ii) systematic use of diagnostically validated approaches to OIC diagnosis and assessment (i.e., Rome IV criteria and Bristol Stool Scale, respectively) across various medical contexts; and (iii) awareness about appropriate, evidence-based treatments for OIC including available peripheral mu-opioid receptor antagonists (PAMORAs).

Conclusions

Physicians who prescribe long-term opioids should be forthcoming with patients about the possibility of OIC and be adequately versed in the most recent guideline recommendations for its management.

Comparing the effectiveness of magnesium oxide and naldemedine in preventing opioid-induced constipation: a proof of concept, single institutional, two arm, open-label, phase II, randomized controlled trial: the MAGNET study

Background

Patients taking opioids are known to develop opioid-induced constipation (OIC), which reduces their quality of life. The aim of this study is to compare magnesium oxide with naldemedine and determine which is more effective in preventing OIC.

Methods

This proof-of-concept, prospective, randomized controlled trial commenced in Japan in March 2018. Initially, a questionnaire-based survey will be conducted targeting adult patients with cancer who concomitantly commenced opioid treatment and OIC prevention treatment. Patients will then be randomly allocated to a magnesium oxide group (500 mg thrice daily) or a naldemedine group (0.2 mg once daily). Each drug will be orally administered for 12 weeks. The primary endpoint is defined as any improvement in scores on the Japanese version of Patient Assessment of Constipation Quality of Life questionnaire (JPAC-QOL) from baseline to 2 weeks of treatment.

Discussion

The primary endpoint is change in JPAC-QOL score from baseline to 2 weeks of intervention. The key secondary endpoint will be change in spontaneous bowel movements at 2 and 12 weeks of intervention. This study will determine whether magnesium oxide or naldemedine is more effective for the prevention of OIC.

Trial registration

University Hospital Medical Information Network (UMIN) Clinical Trials Registry, UMIN000031891. Registered March 25, 2018.

The Impact of Alvimopan on Return of Bowel Function After Major Spine Surgery - A Prospective, Randomized, Double-Blind Study

BACKGROUND

Pain management following major spine surgery requires high doses of opioids and is associated with a risk of opioid-induced constipation. Peripheral mu-receptor antagonists decrease the gastrointestinal complications of perioperative systemic opioid administration without antagonizing the analgesic benefits of these drugs.

OBJECTIVE

To investigate the impact of alvimopan in opioid-naive patients undergoing major spine surgery.

METHODS

Patients undergoing >3 levels of thoracic and/or lumbar spine surgery were enrolled in this prospective, randomized, double-blind study to receive either alvimopan or placebo prior to and following surgery. Opioid consumption; pain scores; and time of first oral intake, flatus, and bowel movement were recorded.

RESULTS

A total of 24 patients were assigned to the active group and 25 were assigned to the placebo group. There was no significant difference in demographics between the groups. Postoperatively, the alvimopan group reported earlier time to first solid intake [median (range): alvimopan: 15 h (3-25) vs placebo: 17 h (3-46), P < .001], passing of flatus [median (range): alvimopan: 22 h (7-63) vs placebo: 28 h (10-58), P < .001], and first bowel movement [median (range): alvimopan: 50 h (22-80) vs placebo: 64 h (40-114), P < .001]. The alvimopan group had higher pain scores (maximum, minimum, and median); however, there was no significant difference between the groups with postoperative opioid use.

CONCLUSION

This study shows that the perioperative use of alvimopan significantly reduced the time to return of bowel function with no increase in postoperative opioid use despite a slight increase in pain scores.

Prolonged-Release (PR) Oxycodone/Naloxone Improves Bowel Function Compared with Oxycodone PR and Provides Effective Analgesia in Chinese Patients with Non-malignant Pain: A Randomized, Double-Blind Trial

Introduction

Prolonged-release oxycodone/naloxone (OXN PR), combining an opioid analgesic with selective blockade of enteric µ-opioid receptors, provided effective analgesia and improved bowel function in patients with moderate-to-severe pain and opioid-induced constipation in clinical trials predominantly conducted in Western countries. This double-blind randomized controlled trial investigated OXN PR (N = 116) versus prolonged-release oxycodone (OXY PR, N = 115) for 8 weeks at doses up to 50 mg/day in patients with moderate-to-severe, chronic, non-malignant musculoskeletal pain and opioid-induced constipation recruited in China.

Methods

A total of 234 patients at least 18 years of age with non-malignant musculoskeletal pain for more than 4 weeks that was moderate-to-severe in intensity and required round-the-clock opioid therapy were randomized (1:1) to OXN PR or OXY PR. The primary endpoint was bowel function using the Bowel Function Index (BFI). Secondary endpoints included safety, Brief Pain Inventory-Short Form (BPI-SF), use of analgesic and laxative rescue medication, and health-related quality of life (EQ-5D).

Results

While BFI scores were comparable at baseline, at week 8 improvements were greater with OXN PR vs OXY PR (least squares mean [LSM] difference (95% CI) − 9.1 (− 14.0, − 4.2); P < 0.001. From weeks 2 to 8, mean BFI scores were in the range of normal bowel function (≤ 28.8) with OXN PR but were in the range of constipation (> 28.8) at all timepoints with OXY PR. Analgesia with OXN PR was similar and non-inferior to OXY PR on the basis of modified BPI-SF average 24-h pain scores at week 8: LSM difference (95% CI) − 0.3 (− 0.5, − 0.1); P < 0.001. The most frequent treatment-related AEs were nausea (OXN PR 5% vs OXY PR 6%) and dizziness (4% vs 4%).

Conclusion

OXN PR provided clinically meaningful improvements in bowel function and effective analgesia in Chinese patients with moderate-to-severe musculoskeletal pain and pre-existing opioid-induced constipation.

Trial Registration

ClinicalTrials.gov, identifier NCT01918098.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01244-x) contains supplementary material, which is available to authorized users.

Prevention and management of diarrhea associated with naldemedine among patients receiving opioids: a retrospective cohort study

BACKGROUND

Naldemedine, a novel peripherally-acting mu-opioid receptor antagonist, has improved opioid-induced constipation in randomized controlled trials. The most frequent adverse event of naldemedine is diarrhea, which can cause abdominal pain and often leads to treatment discontinuation. We aimed to identify risk factors and appropriate management strategies for key adverse events including diarrhea associated with naldemedine, since those have not been extensively studied.

METHODS

We conducted a multi-center retrospective cohort study. Eligible patients had cancer, had undergone palliative care at participating centers, had been prescribed regular opioids, and had taken at least one dose of naldemedine between June 2017 and March 2018. The primary endpoint was the incidence of diarrhea according to baseline characteristics. Secondary endpoints included the duration of naldemedine administration, daily defecation counts before and after starting naldemedine, duration and severity of diarrhea as an adverse event of naldemedine, other adverse events, and the incidence of constipation within 7 days after recovery from diarrhea. We defined patients who started naldemedine within three days of starting a regularly prescribed opioid as the early group, and the remainder as the late group.

RESULTS

Among 103 patients who received naldemedine, 98 fulfilled the eligibility criteria. The median age was 68 years and 48% of the patients were female. Median performance status was 3, and the median oral intake was 50%. The median duration of naldemedine administration and overall survival were 25 and 64 days, respectively. The incidence of diarrhea in the early group (n = 26) was significantly lower than in the late group (n = 72) (3.9% vs. 22.2%, p = 0.02). Daily defecation counts increased after late (median 0.43 to 0.88, p < 0.001), but remained stable after early naldemedine administration (median 1.00 to 1.00, p = 0.34). Constipation after the diarrhea was resolved was common (53%), especially among patients who stopped naldemedine (78%). The diarrhea was improved within three days in 92% of patients who stopped other laxatives.

CONCLUSIONS

The early administration of naldemedine is beneficial because it reduces adverse events including diarrhea. Diarrhea caused by naldemedine can be effectively managed by stopping other laxatives while continuing naldemedine.

Opioid-Induced Constipation in Oncological Patients: New Strategies of Management

OPINION STATEMENT

Cancer-associated pain has traditionally been treated with opioid analgesics, often in escalating doses. Opioid-induced constipation (OIC) is a common problem associated with chronic use of opioid analgesics. Typical treatment strategies to alleviate constipation are based on dietary changes, exercise, and laxatives. However, laxatives have a nonspecific action and do not target underlying mechanisms of OIC. This article will review prevalent, clinical presentation and recommendations for the treatment of OIC. An independent literature search was carried out by the authors. We reviewed the literature for randomized controlled trials that studied the efficacy of laxatives, naloxone, and naloxegol in treating OIC. Newer strategies addressing the causal pathophysiology of OIC are needed for a more effective assessment and management of OIC. Finally, traditional recommended therapies are appraised and compared with the latest pharmacological developments. Future research should address whether naloxegol is more efficacious by its comparison directly with first-line treatments, including laxatives.

Gastrointestinal Motility Issues in Cancer Patients

PURPOSE OF REVIEW

This paper seeks to highlight GI motility disorders that are frequently present in patients with a malignancy. GI dysmotility can occur due to the cancer itself or as a consequence of medical and surgical treatments. Often, symptoms are nonspecific and the diagnosis requires a high index of suspicion. The goal of the paper is to review the common motility problems seen in patients with cancer, their clinical manifestations, and options for management.

RECENT FINDINGS

Studies show that newer endoscopy techniques such as endoscopic mucosal dissection can cause esophageal dysmotility. Opioid-induced constipation is frequently encountered in patients with cancer. Motility disorders in cancer patient can lead to clinical morbidity, poor quality of life, and malnutrition. Newer diagnostic tests and medical and surgical treatments may be helpful in improving the diagnosis and management of these disorders.

Patient and provider differences in the treatment of opioid-induced constipation: a qualitative study

BACKGROUND

Patients using opioids to treat chronic non-cancer pain often experience side effects that may affect health-related quality of life (HRQOL). These side effects include opioid-induced constipation (OIC), sedation, dizziness, and nausea. OIC can significantly affect HRQOL for patients on a daily basis. However, it is not well understood whether patients and clinicians view OIC management similarly.

AIMS

In this study, we sought to elucidate the decision-making process around managing OIC by assessing patient and provider treatment preferences, experiences, and communication regarding this condition.

METHODS

We conducted semi-structured interviews with 33 clinicians, and held three focus groups with patients who were currently using or had used opioids for chronic non-cancer pain. We then analyzed transcribed interviews using descriptive qualitative methods based on grounded theory methodology.

RESULTS

Clinicians recognized OIC as a concern but prioritized pain management over constipation. They focused on medication-based treatments for OIC, but also recommended lifestyle changes (e.g., diet) and reducing opioids to relieve symptoms. Patients reported using over-the-counter treatments, but the majority focused on diet-related constipation management. Patients reported not receiving adequate information from clinicians about OIC and relevant treatments. Cost of treatment was a major concern for both patients and clinicians.

CONCLUSIONS

Assessing experiences with and preferences for OIC treatment, including cost, ease of access, and side effects, could improve patient-provider communication and HRQOL. Quality improvement efforts can target uncovered misalignments between patients and clinicians to improve communication about opioid medication adverse effects and relevant treatment options, which may help improve quality of life for patients with chronic pain.

More opioids, more constipation? Evaluation of longitudinal total oral opioid consumption and self-reported constipation in patients with cancer

PURPOSE

Opioid-induced constipation (OIC) is a distressing physical symptom for patients with cancer taking opioids. Total opioid consumption may contribute to developing worsening OIC-related symptoms. We completed a retrospective analysis examining the association of total daily opioid consumption on self-reported constipation in patients with cancer.

METHODS

In over 5 clinic visits, we collected self-reported constipation scores and 24-h oral morphine equivalents (OME). We examined the association between OME and the presence of constipation (i.e., score > 3) and the relationship of OME between patients with or without constipation.

RESULTS

Of 297 patients with cancer, we observed 57.8% with constipation and 42.4% without constipation at the first clinic visit. Age was similar in both groups (54.2 ± 14.5 vs. 56.4 ± 14.8 years [mean ± SD]) and the majority of patients were women (63.7% vs. 61.1%). The most common cancer type in patients with constipation was non-colorectal gastrointestinal (n = 25, 14.6%), while in patients without constipation was colorectal gastrointestinal (n = 25; 19.8%). Across visits, we observed weak or no association between OME and self-reported constipation (r = 0.01-0.27). At the first visit, higher mean OME was seen in patients who self-reported constipation (133.4 vs 76; p < 0.05). Age, sex, metastatic disease, and stimulant laxative use were not associated with constipation.

CONCLUSIONS

We observed weak to no association between OME and constipation in patients with cancer. These results suggest a lack of a clear association between total opioid consumption and self-reported constipation.

Pathophysiology and management of opioid-induced constipation: European expert consensus statement

Background

Opioid-induced bowel dysfunction is a complication of opioid therapy, in which constipation is the most common and problematic symptom. However, it is frequently under-recognised and thus effective management is often not instituted despite a number of treatment options.

Objective

The central objective of this study is to provide a summary of the pathophysiology and clinical evaluation of opioid-induced constipation and to provide a pragmatic management algorithm for day-to-day clinical practice.

Methods

This summary and the treatment algorithm is based on the opinion of a European expert panel evaluating current evidence in the literature.

Results

The pathophysiology of opioid-induced constipation is multi-faceted. The key aspect of managing opioid-induced constipation is early recognition. Specific management includes increasing fluid intake, exercise and standard laxatives as well as addressing exacerbating factors. The Bowel Function Index is a useful way of objectively evaluating severity of opioid-induced constipation and monitoring response. Second-line treatments can be considered in those with recalcitrant symptoms, which include gut-restricted or peripherally acting mu-opioid receptor antagonists. However, a combination of interventions may be needed.

Conclusion

Opioid-induced constipation is a common, yet under-recognised and undertreated, complication of opioid therapy. We provide a pragmatic step-wise approach to opioid-induced constipation, which should simplify management for clinicians.

Pharmacological Treatment of Opioid-Induced Constipation Is Effective but Choice of Endpoints Affects the Therapeutic Gain

BACKGROUND

Widespread opioid use has led to increase in opioid-related adverse effects like constipation. We examined the impact of study endpoints on reported treatment benefits.

METHODS

Using MEDLINE, EMBASE, and ClinicalTrials.gov, we searched for randomized control trials targeting chronic opioid-induced constipation (OIC) and subjected them to meta-analysis. Data are given with 95% confidence intervals.

RESULTS

Thirty trials met our inclusion criteria. Combining all dichotomous definitions of responders, active drugs were consistently more effective than placebo, with an odds ratio (OR): 2.30 [2.01-2.63; 15 studies], independent of the underlying drug mechanism. The choice of endpoints significantly affected the therapeutic gain. When time from drug administration to defecation was used, the OR decreased from 4.74 [2.71-4.74] at 6 h or less to 2.46 [1.80-3.30] at 24 h (P < 0.05). Using other response definitions, the relative benefit over placebo was 2.10 [1.77-2.50; 12 studies] for weekly bowel frequency, 2.03 [1.39-2.95; 9 studies] for symptom scores, 2.21 [1.25-3.90; 4 studies] for global assessment scales, and 1.27 [0.79-2.03; 7 studies] for rescue laxative use.

CONCLUSION

While treatment of OIC with active drugs is more effective than placebo, the relative gain depends on the choice of endpoints. The commonly used time-dependent response definition is associated with the highest response rate but is of questionable relevance in a chronic disorder. The limited data do not clearly demonstrate a unique advantage of the peripherally restricted opioid antagonists, suggesting that treatment with often cheaper agents should be optimized before shifting to these novel expensive agents.

The patient burden of opioid-induced constipation: New insights from a large, multinational survey in five European countries

BACKGROUND

Despite its high prevalence, opioid-induced constipation (OIC) remains under-recognised and undertreated, and its true impact on wellbeing and quality of life (QoL) may be underestimated.

METHODS

A quantitative, questionnaire-based international survey was conducted.

RESULTS

Weak-opioid users appeared as bothered by constipation as strong-opioid users (38% vs 40%, respectively; p = 0.40), despite it causing less-severe physical symptoms and impact on QoL. Strong-opioid users meeting Rome IV OIC criteria appeared to experience greater symptomatic and biopsychosocial burden from constipation than those not satisfying these criteria. Almost one-fifth of respondents were dissatisfied with their current constipation treatment and around one-third found balancing the need for adequate pain relief with constipation side effects challenging. Consequently, more than half failed to adhere to their prescribed treatment regimens, or resorted to suboptimal strategies, e.g. 40% reduced their opioid intake, to relieve constipation. Almost 60% of healthcare professionals did not adequately counsel patients about constipation as a common side effect of opioid use.

CONCLUSIONS

Findings suggest that both weak- and strong-opioid users suffer comparable bother and decreased QoL, Rome IV criteria can identify patients with more-severe OIC, but may underdiagnose patients showing fewer symptoms, and increased education is needed to manage patients' expectations and enable improved OIC self-management.

Analysis of Nausea in Clinical Studies of Lubiprostone for the Treatment of Constipation Disorders

BACKGROUND

Lubiprostone is a ClC-2 chloride channel activator approved for the treatment of chronic idiopathic constipation (CIC) and opioid-induced constipation (OIC) in adults and irritable bowel syndrome with constipation (IBS-C) in women. Lubiprostone is generally well tolerated, with nausea being the most common adverse event.

AIMS

To characterize nausea with lubiprostone using pooled results from clinical studies in patients with CIC, OIC, or IBS-C.

METHODS

Data from three 3- and 4-week placebo-controlled studies and three long-term open-label studies were pooled for the CIC analysis. The OIC and IBS-C analyses each used pooled data from three 12-week placebo-controlled studies and one 36-week open-label extension study.

RESULTS

The populations included the following numbers of patients: CIC, 316 (placebo) and 1113 (lubiprostone 24 mcg twice daily [BID]); OIC, 652 (placebo) and 889 (lubiprostone 24 mcg BID); and IBS-C, 435 (placebo) and 1011 (lubiprostone 8 mcg BID). The incidence of nausea in lubiprostone-treated patients ranged from 11.4 to 31.1%, with the highest incidence in patients with CIC. Among patients with any nausea, most reported only mild or moderate severity (96.5-99.1% across indications) and only one event (83.6-88.7%); most events occurred within the first 5 days of treatment.

CONCLUSIONS

Nausea was the most common adverse event following the treatment with lubiprostone. Event rates varied by indication and dose, and the majority of nausea adverse events were mild to moderate in severity. Nausea events predominantly occurred early in the treatment period in all of the pooled study populations.

When People with Opioid-Induced Constipation Speak: A Patient Survey

Introduction

Opioid-induced constipation (OIC) is a common consequence of opioid use for chronic pain. OIC creates problems for patients independent of their pain syndromes, in addition to threatening pain treatment effectiveness. Healthcare practitioners need to be alert to how patients talk about OIC so that it is not missed. Using a survey mechanism, we sought patient expressions of the personal impact OIC imposes on how they are able to live their lives and on meanings that symptom relief would produce.

Methods

We used an online survey asking adults with OIC about quality of life implications of OIC and focused on open-ended text responses to questions about personal impacts of straining and meanings attached to OIC symptom relief. Participants were from the US, Canada, UK, Germany, Sweden, and Norway.

Results

A survey of 513 people with OIC produced 280 text responses concerning the impacts of straining on quality of life and 469 text responses on the meaning OIC symptom relief would confer. Text responses about the quality of life impacts of straining often included explicit descriptions conveying physical, psychological, or practical problems. Text responses about the meaning conferred from OIC symptom relief primarily concentrated around freedom from the constraints that OIC can impose.

Conclusions

Patients are willing and able to comment on the problems OIC cause them, using a variety of terms and phrases. Their comments concerning impacts on their lives will often refer to physical consequences, psychological effects, or practical implications. These insights provide healthcare practitioners guidance on how to engage patients about OIC.

Healthcare resource use and costs of opioid-induced constipation among non-cancer and cancer patients on opioid therapy: A nationwide register-based cohort study in Denmark

BACKGROUND AND AIM

Opioid analgesics are often effective for pain management, but may cause constipation. The aim of this study was to determine healthcare resource use and costs in non-cancer and cancer patients with opioid-induced constipation (OIC).

METHODS

This was a nationwide register-based cohort study including patients ≥18 years of age initiating ≥4 weeks opioid therapy (1998-2012) in Denmark. A measure of OIC was constructed based on data from Danish national health registries, and defined as ≥1 diagnosis of constipation, diverticulitis, mega colon, ileus/subileus, abdominal pain/acute abdomen or haemorrhoids and/or ≥2 subsequent prescription issues of laxatives. Total healthcare resource utilization and costs (including pharmacy dispense, inpatient-, outpatient-, emergency room- and primary care) were estimated according to OIC status, opioid treatment dosage and length, gender, age, marital status, and comorbidities using Generalised Linear Model.

RESULTS

We identified 97169 eligible opioid users (77568 non-cancer and 19601 patients with a cancer diagnosis). Among non-cancer patients, 15% were classified with OIC, 10% had previous constipation, and 75% were without OIC. Patients characteristics of non-cancer OIC patients showed a higher frequency of strong opioid treatment (69% versus 41%), long-term opioid treatment (1189 days versus 584 days), advanced age (73 years versus 61 years), and cardiovascular disease (31% versus 19%) compared to those without OIC (P<0.001 for all comparisons). Non-cancer patients with OIC had 34% higher total healthcare costs compared to those without OIC (P<0.001) after adjusting for age, gender, opioid usage, marital status and comorbidities. Among cancer patients, 35% were classified with OIC, 14% had previous constipation, and 51% were without OIC. A higher proportion of cancer patients with OIC were continuous opioid users (85% versus 83%) and strong opioid users (97% versus 85%), compared to those without OIC (P<0.001 for both comparisons). Further, the mean number of days on opioids were higher for cancer patients with versus without OIC (329 days versus 238 days, P<0.001). Total healthcare costs were 25% higher for cancer patients with versus without OIC (P<0.001) after adjusting for age, gender, opioid usage, marital status and comorbidities.

CONCLUSIONS

The results of this nationwide study based on real life data suggested that both non-cancer patients and cancer patients suffering from opioid-induced constipation (OIC) may have higher healthcare resource utilization and higher associated costs compared to those without OIC.

IMPLICATIONS

Reducing the number of OIC patients has potential cost savings for the health care system. Special attention should be on patients at potential high risk of OIC, such as strong and long-term opioid treatment, advanced age, and concomitant cardiovascular disease.

Nanoconjugated NAP as a Potent and Periphery Selective Mu Opioid Receptor Modulator To Treat Opioid-Induced Constipation

Opioids are the mainstay for cancer and noncancer pain management. However, their use is often associated with multiple adverse effects. Among them, the most common and persistent one is probably opioid-induced constipation (OIC). Periphery selective opioid antagonists may alleviate the symptoms of OIC without compromising the analgesic effects of opioids. Recently our laboratories have identified one novel lead compound, 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-[(4'-pyridyl)acetamido]morphinan (NAP), as a peripherally selective mu opioid receptor ligand carrying subnanomolar affinity to the mu opioid receptor and over 100-folds of selectivity over both the delta and kappa opioid receptors, with reasonable oral availability and half-life, and potential to treat OIC. Nanoparticle-based drug delivery systems are now widely considered due to their technological advantages such as good stability, high carrier capacity, low therapeutic side effects, etc. Herein we report nanoparticle supported NAP as a potential candidate for OIC treatment with improved peripheral selectivity over the original lead compound NAP.

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.

Opioids and GI Motility-Friend or Foe? ACTA ACUST UNITED AC. 2016;14:478-494. [PMID: 27807793 DOI: 10.1007/s11938-016-0112-0]

OPINION STATEMENT

The use of opioids for the treatment of chronic non-cancer pain is growing at an alarming rate. Opioid-induced bowel dysfunction (OBD) is a common adverse effect of long-term opioid treatment manifesting as constipation, nausea, and vomiting. These effects are primarily mediated by peripheral μ-opioid receptors with resultant altered GI motility and function. As a result, patients may present with opioid-induced constipation (OIC), opioid-induced nausea and vomiting (OINV), and/or narcotic bowel syndrome (NBS). This often leads to decreased quality of life and in many cases, discontinuation of opioid therapy. There is limited evidence to support the use of traditional anti-emetics and laxatives in the treatment of OBD. Tapering the dose of opioids, switching to transdermal application, opioid rotation, or dual-action opioids, such as tapentadol, may be helpful in the treatment of OBD. Novel agents, such as peripherally acting μ-opioid receptor antagonists which target the cause of OIC, show promise in the treatment of OBD and should be considered when conventional laxatives fail. This chapter will review the pathophysiology of OBD, including OINV and OIC, and treatment options available.

Impact of Treatment with Naloxegol for Opioid-Induced Constipation on Patients' Health State Utility

Introduction

Opioid-induced constipation (OIC) is the most common side effect of opioid treatment. Treatment for OIC typically involves a laxative. However, some patients have an inadequate response to these (laxative inadequate responders, or LIR). This has led to the development of treatments such as naloxegol. This analysis estimates the impact of naloxegol on the health state utility of LIR patients, examines if this utility impact is driven by the change in OIC status, and estimates the utility impact of relief of OIC.

Methods

The analysis was conducted using data from two 12-week randomized controlled trials, KODIAC 4 (ClinicalTrials.gov identifier, NCT01309841) and KODIAC 5 (ClinicalTrials.gov identifier, NCT01323790), plus KODIAC 7 (ClinicalTrials.gov identifier, NCT01395524), a 12-week extension to KODIAC 4. All were designed to assess the efficacy and safety of oral naloxegol (12.5 and 25 mg) compared to placebo. Health state utility data were collected through the EuroQol—five dimensions questionnaire (EQ-5D-3L). Descriptive analysis was undertaken to estimate how EQ-5D utility scores and EQ-5D domain responses varied with treatment, OIC status, and over time. A repeated measure mixed-effects model was used to predict the change from baseline in health state utility score over time.

Results

Compared with placebo, LIR patients treated with naloxegol 25 mg reported a 0.08 improvement in the EQ-5D overall score after 12 weeks of treatment. The analyses also suggest that change in OIC status is a key driver of the impact of OIC treatment on health state utility. When other factors are controlled, relieving OIC is associated with a 0.05 improvement in health state utility, although treatment with naloxegol is associated with an improvement in health state utility over and above the improvement in OIC status.

Conclusion

These analyses suggest that treatment with naloxegol improves patients’ health state utility; driven predominantly by the relief of patients’ constipation.

Funding

AstraZeneca.

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

BACKGROUND

Approximately 20-30% of Canadians suffer from chronic pain. Guidelines for the management of chronic pain support the use of controlled-release (CR) opioids to treat chronic pain. Although effective in managing chronic pain, oxycodone is associated with high rates of opioid-induced constipation (OIC). The cost-effectiveness of a combination of oxycodone for the management of pain and naloxone for the relief of OIC has not previously been evaluated for Canada.

METHODS

A decision analytic model was developed to estimate the cost-utility of combination oxycodone/naloxone compared to oxycodone alone in four populations. Drug costs for managing pain and healthcare costs related to managing OIC were included in the analysis and the primary measure of effectiveness was quality adjusted life years (QALYs) derived from OIC rates observed in clinical trials. The analysis was conducted from a healthcare system perspective, used a 1-year time horizon, and results were expressed in 2015 Canadian dollars.

RESULTS

In all four patient populations, there was a trade-off between slightly higher total expected costs for Targin treated patients compared to oxycodone treated patients, but also improved clinical benefits in terms of reduced OIC, which resulted in higher QALYs for patients. Although analgesic costs were found to be slightly higher for Targin treated patients, Targin also resulted in cost offsets to the healthcare system in terms of less rescue laxative drug use and other resources required for the management of OIC. The resulting 1-year cost-utility of Targin compared to oxycodone ranged from $2178-$7732 per QALY gained in the base case analysis, and it was found that these cost-utility results remained robust and at low values throughout a series of one-way deterministic analyses of uncertainty.

CONCLUSION

The clinical effectiveness of oxycodone/naloxone in managing pain and OIC compared to CR oxycodone alone resulted in low cost-utility estimates.

Naloxegol: the first orally administered, peripherally acting, mu opioid receptor antagonist, approved for the treatment of opioid-induced constipation

Treatment of opioid-induced constipation (OIC) is becoming a relevant clinical challenge as most of the treatments demonstrated to be more effective than placebo in treating OIC have safety issues limiting a broad clinical application. Naloxegol is the first orally administered, peripherally acting, µ opioid receptor antagonist approved by the FDA and EMA specifically for the treatment of noncancer patients with OIC. This review summarizes the results of the studies regarding the effects of naloxegol in OIC. Pharmacodynamic studies have demonstrated that naloxegol was able to inhibit gastrointestinal opioid effects while preserving central analgesic actions. Phase II and phase III studies in patients with noncancer OIC have confirmed the efficacy of naloxegol to inhibit OIC, and the most consistent efficacy was seen with the 25-mg dose once daily. Side effects were mainly gastrointestinal in origin (and usually transient and mild) and there were no signs of opioid withdrawal in the studies. Safety and tolerability were shown in a long-term safety study. Considering its efficacy, safety, route of administration and the limitations of most of the other available treatments, naloxegol has the potential to become the first-line treatment for noncancer patients with OIC.