methylnaltrexone and Neoplasms

Antagonists of mu-opioid receptor role in cancer progression remains to be elucidated. The objective of this review was to summarize the available evidence on antagonists of mu-opioid receptor effect on tumor progression and prognosis in different types of cancers and an evaluation of the available findings on their mechanism of action.. We have found studies related to methylnaltrexone (MNTX) and naltrexone (NTX) usage in cancer outcomes-related setting. We found consistent preclinical evidence of a potential action of MNTX and NTX on cancer growth and spread mediated mainly by effect on the opioid growth factor receptor (OGFr) axis, which results in depressed cell replication. However, clinical results are scarce and limited to poor-quality evidence. Further high-quality studies are warranted to study antagonists of mu-opioid receptor role as a therapeutic option in different types of cancer, especially in patients where the classical treatment causes unacceptable side effects.

Topics: Cell Proliferation; Humans; Naltrexone; Narcotic Antagonists; Neoplasms; Quaternary Ammonium Compounds; Receptors, Opioid

Opioid-induced bowel dysfunction (OIBD) is characterised by constipation, incomplete evacuation, bloating, and gastric reflux. It is one of the major adverse events (AEs) of treatment for pain in cancer and palliative care, resulting in increased morbidity and reduced quality of life. This review is a partial update of a 2008 review, and critiques as previous update (2018) trials only for people with cancer and people receiving palliative care.. To assess for OIBD in people with cancer and people receiving palliative care the effectiveness and safety of mu-opioid antagonists (MOAs) versus different doses of MOAs, alternative pharmacological/non-pharmacological interventions, placebo, or no treatment.. We searched CENTRAL, MEDLINE, Embase, CINAHL, and Web of Science (December 2021), clinical trial registries and regulatory websites. We sought contact with MOA manufacturers for further data.. Randomised controlled trials (RCTs) assessing the effectiveness and safety of MOAs for OIBD in people with cancer and people at a palliative stage irrespective of the type of terminal disease.. Two review authors assessed risk of bias and extracted data. The appropriateness of combining data from the trials depended upon sufficient homogeneity across trials. Our primary outcomes were laxation response, effect on analgesia, and AEs. We assessed the certainty of evidence using GRADE and created summary of findings tables.. We included 10 studies (two new trials) randomising in-total 1343 adults with cancer irrespective of stage, or at palliative care stage of any disease. The MOAs were oral naldemedine and naloxone (alone or in combination with oxycodone), and subcutaneous methylnaltrexone. The trials compared MOAs with placebo, MOAs at different doses, or in combination with other drugs. Two trials of naldemedine and three of naloxone with oxycodone were in people with cancer irrespective of disease stage. The trial on naloxone alone was in people with advanced cancer. Four trials on methylnaltrexone were in palliative care where most participants had advanced cancer. All trials were vulnerable to biases; most commonly, blinding of the outcome assessor was not reported.  Oral naldemedine versus placebo Risk (i.e. chance) of spontaneous laxations in the medium term (over two weeks) for naldemedine was over threefold greater risk ratio (RR) 2.00, 95% confidence interval (CI) 1.59 to 2.52, 2 trials, 418 participants, I² = 0%. Number needed to treat for an additional beneficial outcome (NNTB) 3, 95% CI 3 to 4; moderate-certainty evidence). Earlier risk of spontaneous laxations and patient assessment of bowel change was not reported. Very low-certainty evidence showed naldemedine had little to no effect on opioid withdrawal symptoms. There was little to no difference in the risk of serious (non-fatal) AEs (RR 3.34, 95% CI 0.85 to 13.15: low-certainty evidence). Over double the risk of AEs (non-serious) reported with naldemedine (moderate-certainty evidence). Low-dose oral naldemedine versus higher dose Risk of spontaneous laxations was lower for the lower dose (medium term, 0.1 mg versus 0.4 mg: RR 0.69, 95% CI 0.53 to 0.89, 1 trial, 111 participants (low-certainty evidence)). Earlier risk of spontaneous laxations and patient assessment of bowel change not reported. Low-certainty evidence showed little to no difference on opioid withdrawal symptoms (0.1 mg versus 0.4 mg mean difference (MD) -0.30, 95% CI -0.85 to 0.25), and occurrences of serious AEs (0.1 mg versus 0.4 mg RR 0.25, 95% CI 0.03 to 2.17). Low-certainty evidence showed little to no difference on non-serious AEs. Oral naloxone versus placebo Risk of spontaneous laxations and AEs not reported. Little to no difference in pain intensity (very low-certainty evidence). Full data not given. The trial reported that no serious AEs occurred. Oral naloxone + oxycodone versus oxycodone Risk of spontaneous laxations within 24 h. This update's findings for naldemedine and naloxone with oxycodone have been strengthened with two new trials, but conclusions have not changed. Moderate-certainty evidence for oral naldemedine on risk of spontaneous laxations and non-serious AEs suggests in people with cancer that naldemedine may improve bowel function over two weeks and increase the risk of AEs. There was low-certainty evidence on serious AEs. Moderate-certainty evidence for methylnaltrexone on spontaneous laxations over two weeks suggests subcutaneous methylnaltrexone may improve bowel function in people receiving palliative care, but certainty of evidence for AEs was low. More trials are needed, more evaluation of AEs, outcomes patients rate as important, and in children.

Topics: Adult; Analgesics, Opioid; Child; Humans; Naloxone; Naltrexone; Narcotic Antagonists; Neoplasms; Opioid-Induced Constipation; Oxycodone; Palliative Care; Quaternary Ammonium Compounds; Substance Withdrawal Syndrome

Opioid-induced bowel dysfunction (OIBD) is characterised by constipation, incomplete evacuation, bloating, and gastric reflux. It is one of the major adverse events of treatment for pain in cancer and in palliative care, resulting in increased morbidity and reduced quality of life.This is an update of two Cochrane reviews. One was published in 2011, Issue 1 on laxatives and methylnaltrexone for the management of constipation in people receiving palliative care; this was updated in 2015 and excluded methylnaltrexone. The other was published in 2008, Issue 4 on mu-opioid antagonists (MOA) for OIBD. In this updated review, we only included trials on MOA (including methylnaltrexone) for OIBD in people with cancer and people receiving palliative care.. To assess the effectiveness and safety of MOA for OIBD in people with cancer and people receiving palliative care.. We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, and Web of Science to August 2017. We also searched clinical trial registries and regulatory websites. We contacted manufacturers of MOA to identify further data.. We included randomised controlled trials (RCTs) that assessed the effectiveness and safety of MOA for OIBD in people with cancer and people at a palliative stage irrespective of the type of terminal disease they experienced.. Two review authors assessed risk of bias and extracted data. The appropriateness of combining data from the trials depended upon sufficient homogeneity across the trials. Our primary outcomes were laxation, impact on pain relief, and adverse events. Impact on pain relief was a primary outcome because a possible adverse effect of MOAs is a reduction in pain relief from opioids. We assessed the evidence on these outcomes using GRADE.. We identified four new trials for this update, bringing the total number included in this review to eight. In total, 1022 men and women with cancer irrespective of stage or at a palliative care stage of any disease were randomised across the trials. The MOAs evaluated were oral naldemedine and naloxone (alone or in combination with oxycodone), and subcutaneous methylnaltrexone. The trials compared with MOA with a placebo or with the active intervention administered at different doses or in combination with other drugs. The trial of naldemedine and the two of naloxone in combination with oxycodone were in people with cancer irrespective of disease stage. The trial on naloxone alone was in people with advanced cancer. The four trials on methylnaltrexone were undertaken in palliative care where most participants had cancer. All trials were vulnerable to biases; four were at a high risk as they involved a sample of fewer than 50 participants per arm.In the trial of naldemedine compared to placebo in 225 participants, there were more spontaneous laxations over the two-week treatment for the intervention group (risk ratio (RR) 1.93, 95% confidence intervals (CI) 1.36 to 2.74; moderate-quality evidence). In comparison with higher doses, lower doses resulted in fewer spontaneous laxations (0.1 mg versus 0.2 mg: RR 0.73, 95% CI 0.55 to 0.95; 0.1 mg versus 0.4 mg: RR 0.69, 95% CI 0.53 to 0.89; moderate-quality evidence). There was moderate-quality evidence that naldemedine had no effect on opiate withdrawal. There were five serious adverse events. All were in people taking naldemedine (low-quality evidence). There was an increase in the occurrence of other (non-serious) adverse events in the naldemedine groups (RR 1.36, 95% CI 1.04 to 1.79, moderate-quality evidence). The most common adverse event was diarrhoea.The trials on naloxone taken either on its own, or in combination with oxycodone (an opioid) compared to oxycodone only did not evaluate laxation response over the first two weeks of administration. There was very low-quality evidence that naloxone alone, and moderate-quality evidence that oxycodone/naloxone, had no effect on analgesia. There was low-quality evidence that oxycodone/naloxone did not increase the risk of serious adverse events and moderate-quality evidence that it did not increase risk of adverse events.In combined analysis of two trials of 287 participants, we found methylnaltrexone compared to placebo induced more laxations within 24 hours (. In this update, the conclusions for naldemedine are new. There is moderate-quality evidence to suggest that, taken orally, naldemedine improves bowel function over two weeks in people with cancer and OIBD but increases the risk of adverse events. The conclusions on naloxone and methylnaltrexone have not changed. The trials on naloxone did not assess laxation at 24 hours or over two weeks. There is moderate-quality evidence that methylnaltrexone improves bowel function in people receiving palliative care in the short term and over two weeks, and low-quality evidence that it does not increase adverse events. There is a need for more trials including more evaluation of adverse events. None of the current trials evaluated effects in children.

Topics: Constipation; Defecation; Female; Gastrointestinal Agents; Humans; Intestinal Diseases; Male; Nalbuphine; Naloxone; Naltrexone; Narcotic Antagonists; Neoplasms; Opioid-Related Disorders; Oxycodone; Palliative Care; Piperidines; Quaternary Ammonium Compounds; Randomized Controlled Trials as Topic; Receptors, Opioid, mu

Mu opioids are among the most widely used drugs for patients with cancer with both acute and chronic pain as well as in the perioperative period. Several retrospective studies have suggested that opioid use might promote tumor progression and as a result negatively impact survival in patients with advanced cancer; however, in the absence of appropriate prospective validation, any changes in recommendations for opioid use are not warranted. In this review, the authors present preclinical and clinical data that support their hypothesis that the mu opioid receptor is a potential target for cancer therapy because of its plausible role in tumor progression. The authors also propose the hypothesis that peripheral opioid antagonists such as methylnaltrexone, which reverses the peripheral effects of mu opioids but maintains centrally mediated analgesia and is approved by the US Food and Drug Administration for the treatment of opioid-induced constipation, can be used to target the mu opioid receptor.

Topics: Animals; Humans; Mice; Molecular Targeted Therapy; Naltrexone; Narcotic Antagonists; Neoplasms; Quaternary Ammonium Compounds; Receptors, Opioid, mu

Opioids are one of the most widely used therapies for the palliative treatment of cancer pain; however, despite their proven analgesic efficacy, they are associated with several adverse effects. Associated with psychological distress and multiple concomitant clinical concerns, constipation is the most commonly occurring adverse effect of chronic opioid therapy in cancer patients. Whilst prophylaxis remains the first-line management option, methylnaltrexone is a recommended treatment option for opioid-related constipation if administration of laxatives is ineffective. Due to its inability to cross the blood-brain barrier, methylnaltrexone exerts a peripheral inhibition of opioid-related effects without influencing the opioid-induced central effects; as a result, the analgesic effect of opioids is unaffected. Moreover, multiple clinical trials, albeit not always conducted specifically in cancer patients, have demonstrated that up to 4 months' treatment with either intravenous or subcutaneous methylnaltrexone provides effective relief from opioid-related constipation and is well tolerated. Preliminary evidence indicates that the addition of methylnaltrexone to standard care for opioid-related constipation may also be advantageous from a pharmacoeconomic perspective. In addition, preliminary data suggest that methylnaltrexone could be associated with some further clinical benefits other than the treatment of opioid-related constipation, such as the improvement of gastric emptying, the relief of nausea/vomiting, and the reduction of the risk of regurgitation and pulmonary aspiration. This narrative review examines the most recent evidence and evaluates the current role of methylnaltrexone in the management of opioid-related constipation, and its potential efficacy in cancer patients. The pharmacokinetics, pharmacodynamics, efficacy and tolerability of methylnaltrexone are discussed.

Topics: Analgesics, Opioid; Constipation; Humans; Naltrexone; Narcotic Antagonists; Neoplasms; Pain; Palliative Care; Quaternary Ammonium Compounds

Cancer-related constipation is common and a significant detractor from patient quality of life. It has many possible causes and is still not well understood. Information is lacking on therapies for cancer-related constipation among current medications approved by the US Food and Drug Administration (FDA). Most agents have only been formally tested in comparison with placebo in chronic idiopathic constipation if at all. Few comparative studies of laxatives have been performed to establish superiority or synergy. As we understand more about the physiology of the gastrointestinal tract, new targeted therapies have become available. These include a selective chloride channel activator, lubiprostone, and a selective 5HT4 serotonin receptor agonist, tegaserod, both of which have been FDA approved for chronic idiopathic constipation. The role of these agents in cancer-related constipation remains to be seen. On the horizon are two investigational peripherally acting opioid receptor antagonists, alvimopan and methylnaltrexone. Preliminary results in cancer-related constipation suggest that these agents may be important additions to our treatment repertoire.

Topics: Alprostadil; Constipation; Fatty Acids; Gastrointestinal Agents; Humans; Indoles; Lubiprostone; Naltrexone; Narcotic Antagonists; Neoplasms; Piperidines; Quaternary Ammonium Compounds; Serotonin Receptor Agonists

Methylnaltrexone is a peripherally acting mu-opioid receptor antagonist that has been shown to relieve severe opioid-induced constipation (OIC) in patients with advanced disease receiving palliative care. Its efficacy remains unknown in cancer patients who are not terminally ill. The primary aim of this study was to evaluate the efficacy of methylnaltrexone over 48 h in cancer patients who were not terminally ill.. In this single-dose phase II trial, cancer patients with a prognosis of ≥3 months and OIC with <3 laxations during the preceding week were eligible. The primary endpoint was a rescue-free laxation ≤4 h after a single dose of methylnaltrexone. Friedman's two-way analysis of variance was conducted for the number of laxations, pain and withdrawal scales, and laxation- and constipation-related symptoms. Univariate/bivariate Cox proportional hazard models for laxation times were employed.. Twelve patients received methylnaltrexone. Eleven patients had an ECOG performance status of 1 or 2. Four (33.3 %) and 5 (41.7 %) patients had rescue-free laxation within 4 and 24 h, respectively, and 10 (83.3 %) had laxation within 48 h (p = 0.006). Difficulty passing a stool improved significantly over 48 h (p = 0.029). The bivariate Cox models revealed that a shorter time to laxation was associated with a higher baseline morphine equivalent daily dose (hazard ratio, 1.02 per 1 mg; p = 0.018) and a smaller number of laxations in the preceding week (hazard ratio, 0.13 per one laxation; p = 0.035). Patients tolerated methylnaltrexone well without opioid withdrawal.. Methylnaltrexone may relieve severe OIC in cancer patients who are not terminally ill. A larger prospective study is justified in this population. (NCT01004393, https://clinicaltrials.gov/show/NCT01004393 ).

Topics: Adult; Aged; Aged, 80 and over; Analgesics, Opioid; Constipation; Female; Humans; Injections, Subcutaneous; Male; Middle Aged; Naltrexone; Narcotic Antagonists; Neoplasm Staging; Neoplasms; Prognosis; Quaternary Ammonium Compounds

Methylnaltrexone (MNTX), a peripherally acting μ-opioid receptor (MOR) antagonist, is FDA-approved for treatment of opioid-induced constipation (OIC). Preclinical data suggest that MOR activation can play a role in cancer progression and can be a target for anticancer therapy.. Pooled data from advanced end-stage cancer patients with OIC, despite laxatives, treated in two randomized (phase III and IV), placebo-controlled trials with MNTX were analyzed for overall survival (OS) in an unplanned post hoc analysis. MNTX or placebo was given subcutaneously during the double-blinded phase, which was followed by the open-label phase, allowing MNTX treatment irrespective of initial randomization.. In two randomized, controlled trials, 229 cancer patients were randomized to MNTX (117, 51%) or placebo (112, 49%). Distribution of patients' characteristics and major tumor types did not significantly differ between arms. Treatment with MNTX compared with placebo [76 days, 95% confidence interval (CI) 43-109 versus 56 days, 95% CI 43-69; P = 0.033] and response (laxation) to treatment compared with no response (118 days, 95% CI 59-177 versus 55 days, 95% CI 40-70; P < 0.001) had a longer median OS, despite 56 (50%) of 112 patients ultimately crossing over from placebo to MNTX. Multivariable analysis demonstrated that response to therapy [hazard ratio (HR) 0.47, 95% CI 0.29-0.76; P = 0.002) and albumin ≥3.5 (HR 0.46, 95% CI 0.30-0.69; P < 0.001) were independent prognostic factors for increased OS. Of interest, there was no difference in OS between MNTX and placebo in 134 patients with advanced illness other than cancer treated in these randomized studies (P = 0.88).. This unplanned post hoc analysis of two randomized trials demonstrates that treatment with MNTX and, even more so, response to MNTX are associated with increased OS, which supports the preclinical hypothesis that MOR can play a role in cancer progression. Targeting MOR with MNTX warrants further investigation in cancer therapy.. NCT00401362, NCT00672477.

Topics: Adult; Aged; Analgesics, Opioid; Constipation; Disease-Free Survival; Female; Humans; Kaplan-Meier Estimate; Laxatives; Male; Middle Aged; Naltrexone; Neoplasms; Quaternary Ammonium Compounds; Receptors, Opioid, mu

Pediatric oncology patients can experience opioid-induced constipation, which may not respond to laxative treatment. Methylnaltrexone is an opioid receptor antagonist that can reverse opioid-induced constipation without affecting analgesia. Published literature on the use of methylnaltrexone in children is very limited. This retrospective review describes the effectiveness and safety of methylnaltrexone for opioid-induced constipation in pediatric oncology patients.. A retrospective review of health records was conducted for pediatric oncology in-patients who were prescribed methylnaltrexone between May 2008 and September 2012 at The Hospital for Sick Children. Demographic, clinical, efficacy, and safety data were collected, including; opioid, laxative, and methylnatrexone dosing and frequency.. Fifteen patients (median age: 14 years, range: 4-17 years) received methylnaltrexone; 12 received a single dose while three received multiple doses. At the time of methylnaltrexone administration, patients were receiving a median oral morphine dose equivalent of 5.7 mg/kg/day (range: 1.5-29.2 mg/kg/day) and had not had any bowel movements for several days despite treatment with multiple laxatives. Methylnaltrexone was given at a mean dose of 0.15 ± 0.02 mg/kg/dose (range: 3-12 mg/dose) as a subcutaneous injection. After 14 of 19 doses administered, patients had a bowel movement within 4 hours. Three patients had documented mild gastrointestinal upset following methylnaltrexone administration. None reported a reduction of pain control or opioid withdrawal symptoms.. This case series suggests that methylnaltrexone is safe and may be effective when given subcutaneously as a 0.15 mg/kg single dose to pediatric oncology patients with opioid-induced constipation.

Topics: Adolescent; Analgesics, Opioid; Child; Child, Preschool; Constipation; Female; Humans; Male; Naltrexone; Narcotic Antagonists; Neoplasms; Pain; Quaternary Ammonium Compounds; Retrospective Studies

Methylnaltrexone, a peripherally-acting quaternary opioid antagonist, is an investigational treatment for opioid-induced constipation in patients with advanced illness. This randomized, parallel-group, repeated dose, dose-ranging trial included a double-blind phase for one week followed by an open-label phase for a maximum of three weeks. Opioid-treated patients with advanced illness who met criteria for opioid-induced constipation despite laxative therapy were potentially eligible. Double-blind treatment occurred on Days 1, 3, and 5; open-label therapy could be administered as often as every other day. The initial dose range of 1mg, 5mg, or 12.5mg was extended by adding a 20mg group during the study while still maintaining the double blind; the initial open-label dose of 5mg could be titrated. The primary outcome was a laxation response within four hours after the first dose. Thirty-three patients received at least one dose of methylnaltrexone. Only one of 10 patients (10%) who received the 1mg dose experienced laxation within four hours of dosing. The median time to laxation was >48 hours for the 1mg dose group, compared to 1.26 hours for all patients receiving >or=5mg (P=0.0003). There was no apparent dose-response above 5mg. Most adverse events were related to the gastrointestinal system, were mild, and did not lead to discontinuation. In conclusion, methylnaltrexone relieved opioid-induced constipation at doses >or=5mg in patients with advanced illness, and did not reduce analgesia or cause opioid withdrawal symptoms.

Topics: Acquired Immunodeficiency Syndrome; Adult; Aged; Aged, 80 and over; Analgesics, Opioid; Diarrhea; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Injections, Subcutaneous; Male; Middle Aged; Naltrexone; Narcotic Antagonists; Neoplasms; Pain; Pain Measurement; Quaternary Ammonium Compounds; Terminal Care

Opioids are prescribed in over 40% of patients with advanced cancer, but side effects occur frequently. In this study we evaluated the development and treatment of opioid induced constipation (OIC), and OIC resolving effect of methylnaltrexone for different opioid subtypes in daily clinical practice.. Patients with cancer using opioids were included in a retrospective chart analysis. Baseline characteristics, data on opioid use, laxative use, and OIC were collected. Patients with OIC who were prescribed methylnaltrexone, were included in a prospective observational trial (NCT01955213).. Thirty-nine of 327 patients (pts) with cancer who were treated with opioids suffered from OIC (overall prevalence 12%; 95%-CI: 8-15%). The prevalence of OIC was similar in patients treated with oxycodone or fentanyl (12 of 81 pts. vs. 18 of 110 pts., RR 0.9; 95%CI 0.4-2.0). The morphine equivalent daily dose did not significantly differ between opioid subtypes (fentanyl 89 mg (IQR 60-180) vs. oxycodone 40 mg (40-80), P = 0.231). Twenty-two individual patients (7%) were admitted for OIC. Most effective laxatives in admitted patients were enemas, methylnaltrexone, or 4-l polyethylene-glycol solution. In the prospective observational study, the effect of methylnaltrexone could be evaluated in 23 patients. Eleven patients achieved the primary endpoint of ≥2 laxation responses out of the first four doses methylnaltrexone, independent of opioid subtype.. OIC is a burdensome clinical problem independent of opioid subtype. Timely intensification of prophylactic laxative treatment, especially when opioid doses increase, may help to prevent OIC. Clinically overt OIC requires a more intensive laxative regimen with for example methylnaltrexone.. NCT01955213 .

Topics: Aged; Analgesics, Opioid; Constipation; Female; Fentanyl; Humans; Laxatives; Male; Middle Aged; Naltrexone; Narcotic Antagonists; Neoplasms; Oxycodone; Pain Management; Prospective Studies; Quaternary Ammonium Compounds; Retrospective Studies; Surveys and Questionnaires

Opioid-induced constipation (OIC) is common among children and adolescents and young adults (AYA) with progressive incurable cancer. Although methylnaltrexone is a successful treatment for OIC in adult cancer patients, no case series has established its safety and efficacy in pediatric cancer patients.. The aim of the study was to describe the safety and efficacy of methylnaltrexone use for OIC in children and AYA with progressive incurable cancer at the end of life in the inpatient and outpatient settings.. We conducted a retrospective review of medical records of children and AYA with progressive incurable cancer who received methylnaltrexone at our institution from May 2008 to June 2013. Pharmacy data were reviewed for each patient and a chart review was performed for documentation of laxation and side effects.. Of the 9 patients (age range: 17 months to 21 years) with progressive incurable cancer who developed OIC, 7 (78%) had laxation after methylnaltrexone administration (0.15 mg/kg/dose). Of these 7 patients, 5 (71%) had laxation with the first dose, and 5 (71%) who responded had a continued response to repeated doses. The longest a patient regularly received methylnaltrexone was 9 months. Of 5 patients with intraabdominal disease, 4 (80%) had laxation. There were no negative side effects in any of the patients. Also, there was no increase in pain either qualitatively or by pain score.. Methylnaltrexone appears to be safe and efficacious in treating OIC in children and AYA with progressive incurable cancer. Methylnaltrexone was tolerated in both the inpatient and outpatient settings and with repeated dosing.

Topics: Adolescent; Analgesics, Opioid; Child; Child, Preschool; Constipation; Double-Blind Method; Female; Humans; Infant; Male; Medical Audit; Naltrexone; Narcotic Antagonists; Neoplasms; Quaternary Ammonium Compounds; Retrospective Studies; Terminally Ill; Young Adult

Opioids are major contributing factors to the problem of constipation in palliative care. Whilst this is without doubt, it remains unclear how much other factors also contribute to the problem. The aim of this audit is to review what other contributing factors are present when methylnaltrexone, the peripheral opioid antagonist is prescribed for constipation. The medical records of people prescribed methylnaltrexone over a four-month period were reviewed to examine certain characteristics of people including the whether the reason for constipation was charted, whether other factors that could contribute to constipation were considered and the effectiveness of methylnaltrexone. Over the study period, 10 people received methylnaltrexone, only 4 of whom had a bowel action less than 24 hours after administration with 3 not having any bowel actions reported 6 days after administration. Whilst all were receiving opioids, the opioids doses were in the moderate range (61-200 mg morphine equivalent). However, all had other factors that could contribute to constipation including impaired functional status and medications with anti-cholinergic effects (mean anti-cholinergic load 4.5). In conclusion, methylnaltrexone is targeted treatment for the management of opioid-induced constipation. However, there is a percentage of people who fail to respond. The impact of other factors on the problem of constipation requires greater clarification.

Topics: Aged; Analgesics, Opioid; Constipation; Female; Humans; Laxatives; Male; Medical Records; Middle Aged; Naltrexone; Narcotic Antagonists; Neoplasms; New South Wales; Outcome Assessment, Health Care; Palliative Care; Quaternary Ammonium Compounds; Risk Factors

When laxative regimens have failed, methylnaltrexone may be indicated for the relief of opioid-induced constipation (OIC) in patients with advanced illness receiving palliative care.. A cost-benefit analysis (CBA), based on a willingness-to-pay (WTP) approach, was performed to determine if methylnaltrexone should be added to the formulary list of drugs being reimbursed by third-party payers in Canada for the treatment of cancer patients in palliative care suffering from OIC.. The WTP study had two components: a decision board explaining treatment options (Component A) and a questionnaire to measure individual WTP using a bidding game approach (Component B). Component A had two options: Option 1 (laxatives only) and Option 2 (laxatives+methylnaltrexone injection). Only participants choosing Option 2 were invited to complete Component B. The results of the WTP survey were then incorporated into a CBA. Within a hypothetical cohort, additional monthly premiums that individuals were willing to pay for methylnaltrexone were compared with the monthly costs to the insurer for providing methylnaltrexone to all patients who would potentially be using it.. Four hundred one Canadians, of age 18 years and older, were surveyed and yielded a WTP in additional monthly insurance premiums of Canadian dollar (CAD) $8.65 (95% confidence interval: CAD$6.17-CAD$11.13). The CBA resulted in additional CAD$89,307 with a cost of CAD$139,840 and benefits of CAD$229,147. A set of 10,000 Monte Carlo simulations resulted in average CBA savings of CAD$145,011 with a 99.86% probability of dominance.. The present CBA provides pharmacoeconomic evidence for the adoption of methylnaltrexone for treating OIC in terminally ill cancer patients.

Topics: Adolescent; Adult; Age Distribution; Analgesics, Opioid; Constipation; Consumer Behavior; Cost of Illness; Cost-Benefit Analysis; Female; Health Care Costs; Humans; Male; Middle Aged; Naltrexone; Narcotic Antagonists; Neoplasms; Ontario; Pain; Palliative Care; Patient Acceptance of Health Care; Quaternary Ammonium Compounds; Sex Distribution; Socioeconomic Factors; Treatment Outcome; Young Adult

Topics: Blood-Brain Barrier; Constipation; Drug Therapy, Combination; Humans; Morphine; Naltrexone; Narcotic Antagonists; Nausea; Neoplasms; Orphan Drug Production; Pain; Quaternary Ammonium Compounds; United States; United States Food and Drug Administration