Pharmacokinetic considerations for drugs that treat diarrhea-predominant irritable bowel syndrome: what's new?

INTRODUCTION

Irritable bowel syndrome (IBS), which presents a significant healthcare and socioeconomic burden, is one of the main issues in the field of therapy. Hence, it is imperative to tackle this matter by evaluating the safety and efficacy of the available treatments and determining the ideal approach for each patient.

AREAS COVERED

We reviewed the pharmacokinetics and safety of pharmacologic interventions administered in diarrhea-predominant IBS (IBS-D) patients. PubMed, Google Scholar and the USFDA databases were searched up to November 2023 to include all updated information on eluxadoline, alosetron, and rifaximin.

EXPERT OPINION

The most effective way to treat IBS-D is to focus on managing the most common symptoms. However, healthcare providers face a challenge when it comes to identifying the right treatment for each patient, and the root cause of this is the diversity of IBS-D population. Studies have shown that there are differences in how men and women metabolize drugs, which may lead to gender-specific adverse reactions. Women tend to have higher drug concentrations in their bloodstream and take longer to eliminate them. Therefore, healthcare providers may need to reduce the dosage for female patients. Integrating IBS care into sustainable development efforts can indirectly contribute to achieving SDGs and promote health and well-being for all.

Eluxadoline-Loaded Eudragit Nanoparticles for Irritable Bowel Syndrome with Diarrhea: Formulation, Optimization Using Box-Behnken Design, and Anti-Diarrheal Activity

Eluxadoline (ELD), a recently approved drug, exhibits potential therapeutic effects in the management and treatment of IBS-D. However, its applications have been limited due to poor aqueous solubility, leading to a low dissolution rate and oral bioavailability. The current study's goals are to prepare ELD-loaded eudragit (EG) nanoparticles (ENPs) and to investigate the anti-diarrheal activity on rats. The prepared ELD-loaded EG-NPs (ENP1-ENP14) were optimized with the help of Box-Behnken Design Expert software. The developed formulation (ENP2) was optimized based on the particle size (286 ± 3.67 nm), PDI (0.263 ± 0.01), and zeta potential (31.8 ± 3.18 mV). The optimized formulation (ENP2) exhibited a sustained release behavior with maximum drug release and followed the Higuchi model. The chronic restraint stress (CRS) was successfully used to develop the IBS-D rat model, which led to increased defecation frequency. The in vivo studies revealed a significant reduction in defecation frequency and disease activity index by ENP2 compared with pure ELD. Thus, the results demonstrated that the developed eudragit-based polymeric nanoparticles can act as a potential approach for the effective delivery of eluxadoline through oral administration for irritable bowel syndrome diarrhea treatment.

Single-dose Pharmacokinetics of Eluxadoline in Healthy Participants With Normal Renal Function and Participants With Renal Impairment

Eluxadoline is approved for the treatment of diarrhea-predominant irritable bowel syndrome in the United States. The impact of renal impairment on the pharmacokinetic (PK) parameters of eluxadoline is currently unknown. This phase 1, open-label, parallel-group study evaluated the PK and safety profile of eluxadoline in 8 participants with renal impairment and 8 matched healthy controls. Of the participants with renal impairment, 2 had severe renal impairment (estimated glomerular filtration rate [eGFR] <30 mL/min/1.73 m² ) and 6 had end-stage renal disease while not yet on dialysis (eGFR <15 mL/min/1.73 m² ). The primary objective was to assess plasma and urine PKs, and plasma protein binding of eluxadoline. In participants with renal impairment, mean plasma concentrations of eluxadoline were consistently higher compared with matched healthy controls: 1.4-fold higher for mean maximum plasma concentration (C_max ) and 2.2-fold higher for mean area under the plasma concentration-time curve from time 0 to time t. The median time to C_max was 2.5 hours in both groups. Although eluxadoline is a locally acting drug with low oral bioavailability, because of the increased systemic exposure in participants with renal impairment as a cautionary measure the lower approved dose of 75 mg twice daily is recommended for individuals with severe renal impairment and end-stage renal disease while not yet on dialysis. Eluxadoline 100 mg single dose was well tolerated in participants with renal impairment and matched healthy controls.

An Open-Label Study to Evaluate the Effect of Eluxadoline on the Single-Dose Pharmacokinetics of Midazolam in Healthy Participants

Eluxadoline is a mixed μ-opioid, κ-opioid receptor agonist, and δ-opioid receptor antagonist, approved in the United States for adults with diarrhea-predominant irritable bowel syndrome. This phase 1, single-center, open-label, single-sequence study was conducted on 30 healthy participants to establish whether steady-state eluxadoline increases systemic exposure of the cytochrome P450 (CYP) 3A4 substrate midazolam. Participants received oral midazolam 4 mg on day 1 with a 7-day washout period. On days 8-16, oral eluxadoline 100 mg was administered twice daily. On day 15, midazolam 4 mg was coadministered with the eluxadoline 100-mg morning dose. Primary outcome measures were pharmacokinetic parameters of midazolam and 1-hydroxy-midazolam. The midazolam and 1-hydroxy-midazolam geometric mean ratios and 90%CIs for maximum plasma drug concentration were 99.0% (91.6-107.0) and 113.8% (104.9-123.5), respectively, and area under the plasma concentration-time curves were 90.5% (83.9-97.6) and 105.1% (99.8-110.7), respectively, demonstrating the 2 treatments were bioequivalent, and there was no clinically significant drug interaction. All treatment-emergent adverse events were treatment related, mild in intensity, with no serious adverse events. These results suggest that eluxadoline has no clinically significant effect on CYP3A4 activity and is, therefore, unlikely to affect the pharmacokinetics of other CYP3A4 substrates.

Eluxadoline Versus Antispasmodics in the Treatment of Irritable Bowel Syndrome: An Adjusted Indirect Treatment Comparison Meta-analysis

Objective: Eluxadoline is a newly approved drug for irritable bowel syndrome (IBS), but it has rarely been compared with positive controls. We aimed to compare eluxadoline with antispasmodics in the treatment of IBS.

Methods: We searched the OVID Medline, Embase, and the Cochrane Central Register of Controlled Trials databases for randomized controlled trials (RCTs) comparing eluxadoline or antispasmodics with placebo. The search was conducted from 1 January 1980, to 1 September 2020, without any language restrictions. The primary efficacy outcome was the relief of abdominal pain, defined by a reduction of pain scores of at least 30% from baseline. The secondary efficacy outcome was the relief of global IBS symptoms, defined by a composite response of a decrease in abdominal pain and improvement in stool consistency on the same day for at least 50% of the days assessed. The data were pooled using a random-effects model. Outcome estimates were pooled by using Risk Ratios (RRs) and P-scores.

Results: Forty-two trials with 8,457 participants were included from 45 articles. Compared with placebo, each of drotaverine, pinaverium, alverine combined with simethicone (ACS) and eluxadoline 100 mg was highly effective in the relief of abdominal pain, with drotaverine [RR, 2.71 (95% CI, 1.70 to 4.32), P-score = 0.95] ranking first. Drotaverine, otilonium, cimetropium, pinaverium, and eluxadoline 100 mg had significantly high the relief of global IBS symptomss, for which drotaverine [RR, 2.45 (95% CI, 1.42 to 4.22), P-score = 0.95] was ranked first. No significant difference was found between these interventions. Pinaverium had a significantly higher the relief of global IBS symptoms than eluxadoline [RR, 1.72 (95% CI, 1.33 to 2.21)] on sensitivity analysis. However, no significant difference was found in the number of adverse events between each intervention and the placebo.

Conclusion: Our network meta-analysis showed that eluxadoline 100 mg was at least as effective as antispasmodics in relieving abdominal pain in IBS. But eluxadoline had more reported adverse events. Antispasmodics are still the first choice for the treatment of IBS.

Efficacy of opioid receptor modulators in patients with irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND

While irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal diseases in clinical practice, it has diverse pathogenesis. Because of its sudden and lingering intractable symptoms, it seriously affects patients work and life. Opioid receptors are G protein-coupled receptors distributed across the brain, spinal cord, skin, and gastrointestinal tract, and each of the subtypes has a unique role and specific distribution. They play a role in regulating gastrointestinal motility, secretion, and visceral sensations in the gastrointestinal tract. Therefore, this meta-analysis aims to evaluate the effects of opioid receptor modulators on improving the symptoms of IBS.

METHODS

Searching the key words (Irritable Bowel Syndromes or Syndrome, Irritable Bowel OR Syndromes, Irritable Bowel OR Colon, Irritable OR Irritable Colon OR Colitis, Mucous OR Colitides, Mucous OR Mucous Colitides OR Mucous Colitis) AND (opioid receptor modulators OR eluxadoline OR Viberzi OR asimadoline OR loperamide), a preliminary search on PubMed (English), EMBASE (English), Cochrane Library (English), China National Knowledge Infrastructure Database (CNKI, Chinese), WanFang (Chinese), VIP citation databases (Chinese) and SinoMed (Chinese) databases yielded 1023 papers published in English and Chinese from inception to July 1, 2019. Nine studies were included in the final meta-analysis. Because this is a systematic review and meta-analysis, ethical approval is not necessary.

RESULTS

The random-effects meta-analysis based on these 9 studies and their 4156 patients found that opioid receptor modulators have a statistically significant beneficial effect on IBS global symptoms (RR = 0.85, 95%CI = 0.79-0.92, P < .01) and bowel movement frequency (SMD = -1.26, 95%CI = -2.49--0.04, P < .05), and while there was an improvement trend in stool consistency and quality of life, these findings were not statistically significant.

CONCLUSIONS

This is the first meta-analysis to examine the use of opioid receptor modulators in IBS, and few adverse events were reported in the available trials. Compared with the control group, eluxadolin has a better effect in improving IBS global symptoms and abdominal pain and has statistical significance and showed a low rate of constipation development in IBS patients in comparison with known effects of other opioid receptor modulators. However, current findings are based on a considerably limited evidence base with marked heterogeneity. Future studies should aim to identify subpopulations of patients with IBS and need to evaluate the long-term safety of these therapies.PROSPERO registration number: CRD42020141597.

In Silico Food-Drug Interaction: A Case Study of Eluxadoline and Fatty Meal

Food-drug interaction is an infrequently considered aspect in clinical practice. Usually, drugs are taken together with meals and what follows may adversely affect pharmacokinetic and pharmacodynamic properties, and hence, the therapeutic effects. In this study, a computational protocol was proposed to explain the different assimilations of two µ-receptors agonists, eluxadoline and loperamide, with a peculiar pharmacokinetic profile. Compared to loperamide, eluxadoline is absorbed less after the intake of a fatty meal, and the LogP values do not explain this event. Firstly, keeping in mind the different pH in the intestinal tract, the protonation states of both compounds were calculated. Then, all structures were subjected to a conformational search by using MonteCarlo and Molecular Dynamics methods, with solvation terms mimicking the water and weak polar solvent (octanol). Both computational results showed that eluxadoline has less conformational freedom in octanol, unlike loperamide, which exhibits constant behavior in both solvents. Therefore, we hypothesize that fatty meal causes the "closure" of the eluxadoline molecule to prevent the exposure of the polar groups and their interaction with water, necessary for the drug absorption. Based on our results, this work could be a reasonable "case study", useful for future investigation of the drug pharmacokinetic profile.

Eluxadoline Loaded Solid Lipid Nanoparticles for Improved Colon Targeting in Rat Model of Ulcerative Colitis

The aim of the current study was to evaluate the therapeutics potential of eluxadoline (ELX) loaded solid lipid nanoparticles (SLNs) in ulcerative colitis. ELX loaded SLNs were prepared using three different lipids according to the solvent emulsification technique. The optimization of prepared SLNs (F1-F3) were carried out based on size, PDI, zeta potential, percent drug entrapment (%EE), and loading (%DL). The lipid (stearic acid) based SLNs (F2) was optimized with particle size (266.0 ± 6.4 nm), PDI (0.217 ± 0.04), zeta potential (31.2 ± 5.19 mV), EE (65.0 ± 4.8%), and DL (4.60 ± 0.8%). The optimized SLNs (F2) was further evaluated by DSC, FTIR, SEM, in vitro release, and stability studies, which confirmed the successful encapsulation of ELX in SLNs. The efficacy of optimized SLNs (F2) in comparison to the pure ELX drug was assessed in acetic acid induced colitis rat models. It was observed that the delivery of ELX by SLNs alleviated the induced acetic acid colitis significantly. Thus, ELX loaded SLNs delivery to the colon has a significant potential to be developed for the treatment of ulcerative colitis.

Update on Eluxadoline for the Treatment of Irritable Bowel Syndrome with Diarrhea: Patient Selection and Perspectives

Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder characterized by chronic abdominal pain associated with changes in bowel habits. It is the most common GI problem seen by gastroenterologists. IBS is a heterogenous disorder encompassing a spectrum of underlying mechanisms and clinical presentations. The pathophysiology of diarrhea-predominant form of IBS (IBS-D) remains poorly understood, and current available therapeutic options for IBS-D are limited. Eluxadoline is a novel, locally acting mixed μ- and κ-opioid receptor agonist and δ-receptor antagonist approved by the Food and Drug Administration (FDA) for treatment of adults with IBS-D. Data from two phase III clinical trials showed that approximately 25–30% of the eluxadoline-treated patients achieved composite clinical response, defined by a reduction of abdominal pain and improvement in stool consistency. Patients who achieve composite response during the first month of therapy were significantly more likely to demonstrate sustained clinical response. The most common adverse events reported with eluxadoline use were constipation, nausea and abdominal pain. The risk of abuse, dependence, or withdrawal is low. Serious adverse events associated with eluxadoline include sphincter of Oddi spasm (SOS) and pancreatitis particularly in patients without a gallbladder. Development of pancreatitis is likely secondary to SOS, but it remains unclear why pancreatitis occurs so quickly after initial doses. This adverse event profile helps guide proper selection of IBS-D patients for eluxadoline use, with important contraindications including absence of a gallbladder, biliary duct obstruction or sphincter of Oddi dysfunction, alcoholism, history of pancreatitis, or structural diseases of the pancreas. With the recent clinical trials demonstrating its efficacy, eluxadoline provides an additional option to the few existing pharmacologic interventions available for IBS-D. In this review, we discuss the drug development, efficacy and safety of eluxadoline, as well as selection criteria for identifying appropriate candidates for this medication.

Effects of treatment with eluxadoline on abdominal pain in patients with IBS-D: Additional post hoc analyses of Phase 3 trials

BACKGROUND

Recurring abdominal pain is a characteristic and often unpredictable and debilitating symptom of irritable bowel syndrome with diarrhea (IBS-D). Measuring the effects of IBS-D treatments on abdominal pain remains a significant challenge in clinical trials. Here, we aimed to examine the effect of eluxadoline through various post hoc analyses.

METHODS

Data from two eluxadoline Phase 3 trials were pooled over 26 weeks, comparing eluxadoline 100 mg twice daily to placebo. Worst abdominal pain (WAP) was measured daily on a 0-10 scale. WAP responder criteria were prospectively defined as a ≥30% improvement in daily WAP score on ≥50% of days. Pairwise, two-sided Cochran-Mantel-Haenszel tests assessed treatment effects. Cumulative distribution functions were used to plot WAP response rates using variations on the response criteria.

KEY RESULTS

Of 1615 patients with IBS-D (66% female, mean age 46 years), 806 received eluxadoline and 809 received placebo; 48.3% and 44.0% were WAP responders (≥30% improvement), respectively (P value not significant). When the response threshold was increased to 50% daily WAP improvement from baseline, a significantly greater percentage of eluxadoline-treated patients versus placebo-treated patients were WAP responders (38.7% vs 32.5%, respectively; P = .009). At Week 26, average WAP changes from baseline were -3.4 and -3.0 points, respectively (P = .002).

CONCLUSIONS AND INFERENCES

Despite small effect sizes, eluxadoline demonstrated consistent and sustained improvement in WAP compared to placebo across a range of prospective and post hoc analyses. Assessing WAP response across a range of measures is important for fully understanding a treatment's efficacy.

Current and emerging pharmacological approaches for treating diarrhea-predominant irritable bowel syndrome

Introduction: Irritable bowel syndrome with diarrhea (IBS-D) is among the most common functional gastrointestinal (GI) disorders and is associated with impaired quality of life, increased health-care utilization, and significant costs to patients and society. The treatment of IBS is typically hierarchal with initial therapies consisting of dietary and lifestyle modifications. Pharmacotherapy with over-the-counter and prescription medications is also commonly used for symptomatic control in the course of therapy.Areas covered: Three medications are approved by the United States Food and Drug Administration (FDA) for IBS-D, with all of them demonstrating efficacy in randomized, placebo-controlled trials. In this review, the authors discuss the clinical trial data applicable to the current FDA approved IBS-D therapies as well as review data related to new and emerging therapies for this condition.Expert opinion: Clinicians should be familiar with emerging therapies for IBS-D as they may provide benefit to some IBS-D patients. The exact mechanisms of action of many of the emerging agents for IBS-D remain unknown. Despite substantial differences and limitations in the design and quality of supporting studies, there is an increasing body of evidence suggesting that emerging agents may promote meaningful symptom improvement in patients with IBS-D.

Management of irritable bowel syndrome with diarrhea: a review of nonpharmacological and pharmacological interventions

Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) condition involving numerous potential causative factors (e.g. alterations in gut microbiota, motility, brain-gut axis). Several interventions are available for the management of patients with IBS, but no universal management algorithm currently exists. The aim of this article is to review interventions that may be considered in the management of patients with IBS with diarrhea (IBS-D). Nonpharmacological interventions include dietary and lifestyle modification, which are generally used as first-line therapy. Probiotics have demonstrated efficacy and safety in patients with IBS, but studies are inconsistent in strains examined, dosing, and treatment duration. Psychological therapies (e.g. cognitive behavioral therapy, hypnotherapy) also may improve IBS symptoms. Pharmacological interventions for the management of IBS-D include the US Food and Drug Administration-approved agents eluxadoline, rifaximin, and alosetron, as well as loperamide, smooth muscle antispasmodics, bile acid sequestrants, and antidepressants (i.e. tricyclic antidepressants, selective serotonin reuptake inhibitors). Eluxadoline and rifaximin have been shown to improve abdominal pain and stool consistency in patients with IBS-D. In addition, data indicate that alosetron improves IBS symptoms; however, it is approved only for women with severe IBS-D. Of the three approved agents, rifaximin has the most favorable safety profile. The risk-benefit ratio is an important consideration with every medication, but is especially important in the treatment of functional GI disorders such as IBS-D. Thus, the most troublesome symptoms, quality of life, symptom intensity, and individual patient preferences should be considered when formulating a management plan for patients with IBS-D.

Impact of patient and disease characteristics on the efficacy and safety of eluxadoline for IBS-D: a subgroup analysis of phase III trials

BACKGROUND

Irritable bowel syndrome with diarrhea (IBS-D) is a prevalent gastrointestinal (GI) disorder with a varied presentation, often overlapping with other GI and non-GI disorders. Eluxadoline is a locally active mixed µ- and κ-opioid receptor agonist and δ-opioid receptor antagonist approved for the treatment of IBS-D in adults. As IBS-D is a heterogeneous disease, factors such as patient demographics, symptom severity, and symptom pattern history can potentially inform treatment selection.

METHODS

Here, we report additional prospectively planned analyses of two large double-blind, placebo-controlled studies (IBS-3001 and IBS-3002) enrolling patients meeting Rome III criteria for IBS-D. Patients were randomized 1:1:1 to receive placebo or eluxadoline 75 mg or 100 mg twice daily. Efficacy (abdominal pain, stool consistency, and composite, simultaneous improvement in both) and safety were assessed for prospectively defined patient subgroups stratified by age, sex, race, presence of comorbidities, and baseline disease characteristics.

RESULTS

Across all age, sex, race, comorbidity, and disease characteristic subgroups, a greater proportion of patients were composite responders with both eluxadoline doses as compared with placebo, including patients with a history of depression or a history of gastroesophageal reflux disease. Among patients aged ⩾65 years, a greater proportion of patients receiving eluxadoline 75 mg were composite, abdominal pain, and stool consistency responders compared with those receiving 100 mg. The proportion of patients with at least one adverse event was slightly higher in patients aged ⩾65 years and also in female patients.

CONCLUSIONS

This analysis suggests that eluxadoline is effective in treating IBS-D across a range of commonly encountered patient types. In contrast to the overall population, patients aged ⩾65 years demonstrated a greater proportion of responders at the lower approved 75 mg eluxadoline dose.

Targeting mu opioid receptors to modulate gastrointestinal function: what have we learnt so far from the studies in functional bowel disorders?

Opioids have recently received much attention because of the epidemic in their use in some countries such as the USA and the UK. Concerns have been raised about the possibility that they can increase mortality in patients when used on a long-term basis. Moreover, they are known to induce paradoxical hyperalgesia as well as alterations of gut function. The analgesic properties of opioids are mediated by receptors located in the brain, but as opioid receptors are also expressed in the gastrointestinal tract, new drugs acting on these receptors have recently been developed to treat two functional disorders, namely irritable bowel syndrome with diarrhoea and opioid-induced constipation. The aim of this article is to highlight some interesting observations resulting from the development of these drugs in the field of functional gastrointestinal disorders.

Evaluation of Eluxadoline Effect on Cardiac Repolarization

This study evaluated the effects of eluxadoline, a mixed μ‐opioid receptor (OR) and κ‐OR agonist and δ‐OR antagonist, on cardiac repolarization. This evaluator‐blinded, placebo‐ and positive‐controlled, 4‐period crossover study randomized healthy men and women to single oral doses of eluxadoline (therapeutic dose 100 mg or supratherapeutic dose 1000 mg), moxifloxacin 400 mg, or placebo. QT data were corrected using individual custom correction (QTcI). The primary endpoint was the change from baseline in QTcI intervals (ΔQTcI) between eluxadoline and placebo (ΔΔQTcI). An upper bound of the 95% confidence interval around ΔΔQTcI of 10 milliseconds was considered clinically significant. Concentration–QTc data were analyzed using a repeated‐measures, mixed‐effects linear model. Sixty‐four volunteers were treated, and 58 completed the study. Assay sensitivity was demonstrated with moxifloxacin (noted by ΔΔQTcI of 11.94 milliseconds). The maximum ΔΔQTcI for eluxadoline 1000 mg was 4.10 milliseconds 1 hour postdose (1‐sided 95% upper confidence bound, 5.81 milliseconds), and for eluxadoline 100 mg was 1.20 milliseconds at 0.5 hours postdose (1‐sided 95% upper confidence bound, 2.91 milliseconds). Primary ΔΔQTcI results were confirmed using Fridericia's formula for QTc. Categorical, morphological, and concentration–QTc analyses were consistent with the primary and secondary findings. There were no significant gender effects on ΔΔQTcI values. The most common adverse events were contact dermatitis and nausea (12.5% each) and dizziness (10.9%); adverse events were more frequent in the eluxadoline 1000 mg group. In conclusion, eluxadoline, at therapeutic or supratherapeutic doses, did not significantly prolong QT intervals, and was safe and generally well tolerated in this study population.

Radar plots: A novel modality for displaying disparate data on the efficacy of eluxadoline for the treatment of irritable bowel syndrome with diarrhea

BACKGROUND

Patients with irritable bowel syndrome with diarrhea (IBS-D) experience a range of abdominal and bowel symptoms; successful management requires alleviation of this constellation of symptoms. Eluxadoline, a locally active mixed μ- and κ-opioid receptor agonist and δ-opioid receptor antagonist, is approved for the treatment of IBS-D in adults based on the results of 2 Phase 3 studies. Radar plots can facilitate comprehensive, visual evaluation of diverse but interrelated efficacy endpoints.

METHODS

Two double-blind, placebo-controlled, Phase 3 trials (IBS-3001 and IBS-3002) randomized patients meeting Rome III criteria for IBS-D to twice-daily eluxadoline 75 or 100 mg or placebo. Radar plots were prepared showing pooled Weeks 1-26 response rates for the primary efficacy composite endpoint (simultaneous improvement in abdominal pain and stool consistency), stool consistency, abdominal pain, urgency-free days, and adequate relief, and change from baseline to Week 26 in IBS-D global symptom score, abdominal discomfort, abdominal pain, abdominal bloating, and daily number of bowel movements.

KEY RESULTS

The studies enrolled 2428 patients. Eluxadoline increased Weeks 1-26 responder proportions vs placebo for the composite endpoint, stool consistency, abdominal pain, urgency-free days, and adequate relief. Changes from baseline to Week 26 in IBS-D global symptom score, abdominal discomfort, abdominal pain, abdominal bloating, and number of bowel movements were greater with eluxadoline vs placebo.

CONCLUSIONS AND INFERENCES

Data presentation in radar plot format facilitates interpretation across multiple domains, demonstrating that eluxadoline treatment led to improvements vs placebo across 13 endpoints representing the range of symptoms experienced by patients with IBS-D.

Advancements in drug development for diarrhea-predominant irritable bowel syndrome

INTRODUCTION

Diarrhea-predominant irritable bowel syndrome (IBS-D) is a common disorder characterized by a complex pathophysiology hampering optimal targeted drug development. Recent advances in our understanding of key underlying mechanisms prompted novel therapeutics including novel pharmacological approaches.

AREAS COVERED

This review summarizes the latest advancements in the pipeline of IBS-D drugs focusing on new pharmacological targets, efficacy and safety of medicinal products considering the recent harmonization of regulatory requirements by the FDA and the EMA.

EXPERT OPINION

The new 5-HT₃ receptor antagonist ramosetron appears a promising therapeutic approach devoid of significant adverse events, although it is presently unavailable in Western countries, most likely because of the precautionary approach taken by regulatory agencies with this drug class. New pharmacological concepts on full agonists/antagonists, mixed-receptor activity and novel drug targets may streamline the present drug pipeline along with the adherence on new regulatory guidelines on outcome measures. Eluxadoline can be taken as an example of this paradigm shift. It has now been granted marketing authorization for IBS-D on both sides of the Atlantic, but it is still considered as a second-line agent by the NICE. There is still much work to be done to fully cover clinical needs of patients with IBS-D.

Preparation, Evaluation and Bioavailability Studies of Eudragit Coated PLGA Nanoparticles for Sustained Release of Eluxadoline for the Treatment of Irritable Bowel Syndrome

Eluxadoline is a newly approved orally administered drug used for the treatment of Irritable Bowel Syndrome with Diarrhea. It is reported as a poorly water-soluble drug due to which its dissolution rate and oral bioavailability are very poor. In this work, various plain PLGA nanoparticles (NPs) (F1–F4) were prepared and optimized based on particle size, PDI, zeta potential and percent drug entrapment efficiency (EE). The developed plain NPs (F1–F4) showed average particle size ranging from 260.19 to 279.76 nm with smooth surface and EE of 17.83–56.29%. The optimized plain NPs (F3) had particle size of 273.76 ± 7.25 nm with a low PDI value 0.327, zeta potential - 30.63 ± 2.47 mV and % EE of 56.29 ± 2.56%. The optimized F3 NPs was further submitted for enteric coating using Eudragit S100 polymer and evaluated in terms of particles characterization, in vitro release and pharmacokinetic studies in rats. The bioavailability of plain and coated nanaoparticles were enhanced by 6.8- and 18.5-fold, respectively, compared to normal suspension. These results revealed that the developed coated NPs could be used for its oral delivery for an effective treatment of Irritable Bowel Syndrome with Diarrhea.

Eluxadoline in irritable bowel syndrome with diarrhea: rationale, evidence and place in therapy

Irritable bowel syndrome (IBS) is the most common gastrointestinal (GI) disorder worldwide, however treatment options for diarrhea-predominant IBS (IBS-D) remain limited. Eluxadoline, a µ- and κ-opioid receptor agonist and δ-opioid receptor antagonist, was recently approved for the treatment of IBS-D. A novel compound first described in 2008, eluxadoline was shown to normalize GI transit, with a subsequent phase I demonstrating its safety and tolerability in healthy adults. In 2016, two randomized, double-blind, placebo-controlled phase III trials studying eluxadoline use at 75 mg and 100 mg twice daily over 26 weeks demonstrated a significant improvement in stool consistency and many global symptoms of IBS. However, the data did not demonstrate a significant advantage over placebo using the United States Food and Drug Administration (US FDA) and European Medicines Agency (EMA) endpoints for abdominal pain. Safety and tolerability data, pooled from both phase II and III studies, suggest that eluxadoline is generally well tolerated with the most common adverse events (AEs) occurring in approximately 3-8% of patients and included nausea, constipation, and abdominal pain. The most common serious adverse event (SAE) is pancreatitis, which had a 0.4% incidence. Recent US FDA reports reporting severe pancreatitis and sphincter of Oddi dysfunction after short-term use of eluxadoline in patients without a gallbladder has added a history of cholecystectomy as an important contraindication. Eluxadoline is also contraindicated in patients with a history of biliary duct obstruction, sphincter of Oddi dysfunction, active alcohol abuse, history of pancreatitis or known pancreatic duct obstruction, severe hepatic impairment, severe or chronic constipation, or known mechanical gastrointestinal obstruction. As a new drug to enter the IBS-D market, the place of eluxadoline in the hierarchy of IBS treatments is still to be determined. In this article, we review the development and clinical trial data behind the approval of eluxadoline with a focus on safety data and its use in clinical practice.

Eluxadoline in the treatment of diarrhea-predominant irritable bowel syndrome

Eluxadoline is a novel drug approved for the management of diarrhea predominant irritable bowel syndrome (IBS-D). It has unique pharmacology and works on three different opioid receptors. Several Phase II and III clinical trials have demonstrated eluxadoline’s efficacy in reducing symptoms related to IBS-D. Clinical trial results and postmarketing reports show a risk of pancreatitis in patients without a gallbladder or those abusing alcohol. This review article will include information on clinical trial results related to IBS-D management as well as eluxadoline’s limitations.

Spotlight on eluxadoline for the treatment of patients with irritable bowel syndrome with diarrhea

BACKGROUND

Irritable bowel syndrome with diarrhea (IBS-D) has limited options for treatment currently, including mainly anti-motility medications, antispasmodics, and antidepressants. This review discusses the properties of a new drug, eluxadoline, a gut-targeting mu- and kappa-opioid receptor agonist and a delta-opioid receptor antagonist, and its efficacy and safety in patients with IBS-D.

MATERIALS AND METHODS

A systematic review of the literature was undertaken to identify studies that had investigated eluxadoline as a treatment in IBS-D. A narrative review of other information is provided with respect to pharmacological and chemical properties. Where suitable, meta-analysis was performed with a random-effects model to produce a pooled estimate.

RESULTS

Eluxadoline showed efficacy improving stool consistency (standardized mean difference [SMD]: -0.29 at 12 weeks, p = 0.0004; -0.46 at 26 weeks, p = 0.0001), global symptoms (SMD: -0.15 at 12 weeks, p = 0.006; -0.14 at 26 weeks, p = 0.02), quality of life (SMD: 0.21 at 12 weeks, p < 0.0001; 0.16 at 26 weeks, p = 0.007), pain (SMD: -0.17 at 12 weeks, p = 0.001; -0.16 at 26 weeks, p = 0.01), and adequate relief (odds ratio [OR]: 1.99 at 12 weeks, p < 0.00001; 1.78 at 26 weeks, p < 0.0001). It also improved IBS severity and other abdominal symptoms such as bloating, discomfort, and risk of urgency and fecal incontinence. Its main side effects included constipation (OR: 3.49, p < 0.00001), vomiting (OR: 3.42, p = 0.0002), abdominal pain (OR: 1.78, p = 0.007), and nausea (OR: 1.42, p = 0.07). The overall quality of trials was satisfactory with the meta-analyses providing largely homogeneous outcomes.

CONCLUSION

Eluxadoline's place in clinical practice might prove useful since the pharmacological options of IBS-D are limited and eluxadoline showed a positive effect in treating the symptoms of IBS-D.

The place of eluxadoline in the management of irritable bowel syndrome with diarrhea

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by abdominal pain associated with defecation with altered stool frequency or stool form. The global prevalence of IBS ranges from 10% to 15% and total healthcare cost attributable to IBS is significant. Among individuals with IBS, the condition has dramatic effects on health-related quality of life, work and school productivity, and activities of daily living. It may be diagnosed with confidence, based on symptom-based diagnostic criteria, exclusion of alarm features and directed diagnostic testing. Management of IBS typically begins with dietary and lifestyle modifications, progressing to over-the-counter therapies, and then to prescription medications, both approved and nonapproved for IBS. This narrative summarizes the efficacy and safety of three US Food and Drug Administration (FDA)-approved prescription therapies for IBS with diarrhea (IBS-D), with a focus on the most recently marketed agent, eluxadoline, and its role in the treatment IBS-D.

New therapeutic options for IBS: the role of the first in class mixed µ- opioid receptor agonist and δ-opioid receptor antagonist (mudelta) eluxadoline

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder which represents a major cost to healthcare services. IBS-D patients represent about one-third of the IBS population and are currently treated with antispasmodics, loperamide, bile acid sequestrants and antidepressants. Alosetron and rifaximin are also available in USA, ramosetron in Japan, Korea and Thailand and ondansetron as an off-label treatment. Areas covered: This article focuses on eluxadoline, a novel pharmacological agent that has recently been approved by both the FDA and EMA for treatment of patients with IBS-D. Expert commentary: The efficacy and safety of eluxadoline in treating bowel habit alterations and pain, both in the short and long-term, make the drug a welcome addition to our therapeutic alternatives in IBS-D. Its positioning in any IBS algorithm will depend on the 'real world' prevalence of the small risk of sphincter of Oddi spasm and mild pancreatitis.

Diarrhea-predominant irritable bowel syndrome: Diagnosis, etiology, and new treatment considerations

PURPOSE

To provide an overview of irritable bowel syndrome (IBS), specifically the efficacy and tolerability of treatment options for diarrhea-predominant IBS (IBS-D).

DATA SOURCES

Research articles available via PubMed were reviewed.

CONCLUSIONS

IBS is a chronic multifactorial disorder that has a negative impact on patient-related quality of life. Genetic factors, psychosociologic factors, alterations in the gut microbiota, and changes in immune, motor, and sensory responses to various stimuli all may be involved in the development of IBS. While pharmacologic therapies for IBS-D have historically been limited (e.g., alosetron), newer therapies (eluxadoline and rifaximin), both approved in the United States in 2015, may be considered for appropriate patients for the management of IBS-D.

IMPLICATIONS FOR PRACTICE

Nurse practitioners play an important role in the diagnosis, care, and management of patients with IBS-D. The goals of therapy should be to reach a correct diagnosis before initiating therapy, provide reassurance to the patient, educate the patient on potential treatment options, improve IBS-D symptoms, minimize risk of harm with treatment, and maximize patient-related quality of life. The authors present a treatment algorithm to guide nurse practitioners on the management of patients with IBS-D.

Emerging treatments in neurogastroenterology: eluxadoline - a new therapeutic option for diarrhea-predominant IBS

BACKGROUND

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder worldwide. The global prevalence of IBS is estimated to be as high as 15%. For many patients, IBS is a chronic disorder which can significantly reduce quality of life. Just as important as the effects on any one individual, IBS also places a significant impact on the population as a whole with its negative effects on the health care system. Irritable bowel syndrome is categorized into one of three main categories: IBS with diarrhea, IBS with constipation, and IBS with mixed bowel habits. Patients with diarrhea-predominant IBS (IBS-D) comprise a substantial proportion of the overall IBS population. A number of therapeutic options exist to treat the symptoms of abdominal pain, bloating, diarrhea, and fecal urgency, including non-pharmacologic therapies such as dietary changes and probiotics, or pharmacologic therapies such as loperamide and alosetron. However, many patients have persistent symptoms despite these therapies. This unmet need led to the development of eluxadoline, a mu-opioid receptor agonist/delta-opioid receptor antagonist/kappa-receptor agonist. Approved by the FDA in May 2015, this medication shows promise in the treatment of diarrhea-predominant IBS for both men and women.

PURPOSE

This monograph will briefly review the impact of IBS, discuss current treatments for IBS-D, and then focus on the pharmacology, clinical efficacy and safety of eluxadoline. Potential mechanisms related to rare events of acute pancreatitis or elevated liver tests will be discussed.

Rifaximin and eluxadoline - newly approved treatments for diarrhea-predominant irritable bowel syndrome: what is their role in clinical practice alongside alosetron?

INTRODUCTION

Diarrhea-predominant irritable bowel syndrome (IBS-D) is a common functional gastrointestinal condition in which patients experience abdominal pain, diarrhea, bloating, cramps, flatulence, fecal urgency, and incontinence.

AREAS COVERED

We review two recently approved therapies that focus on treating underlying pathogenic mechanisms of IBS-D: (1) the non-absorbable antibiotic rifaximin, and (2) the opioid receptor agonist/antagonist eluxadoline. We compare the safety and efficacy data emerging from rifaximin and eluxadoline registration trials with safety and efficacy data from the alosetron clinical development program.

EXPERT OPINION

The rifaximin and eluxadoline clinical development programs for IBS-D have demonstrated significant improvement in IBS-D endpoints compared to placebo. Direct comparison of primary endpoint results from the alosetron, rifaximin, and eluxadoline pivotal trials is not possible; however, general estimates of efficacy can be made, and these demonstrate similar and significantly greater responses to 'adequate relief' and a composite endpoint of abdominal pain/stool form for each agent compared to placebo. With the recent approval in the United States of rifaximin and eluxadoline for IBS-D, how should clinicians employ these agents? We suggest that they be utilized sequentially, taking into consideration patient symptoms and severity, prior medical history, mode of action, cost, availability, managed care coverage, and adverse event profiles.

Current and emerging drug options in the treatment of diarrhea predominant irritable bowel syndrome

INTRODUCTION

Irritable bowel syndrome diarrhea predominant (IBS-D) is a highly prevalent GI disease, affecting nearly a third of all patients diagnosed with irritable bowel syndrome. Current treatment options are limited.

AREAS COVERED

This review discusses the pharmacotherapeutic options for IBS-D including currently used medications, the two newly FDA approved medications, as well as emerging therapies with potential benefit in IBS-D. Particular emphasis is placed on rifaximin and eluxadoline and their possible use in IBS-D.

EXPERT OPINION

Current pharmacological treatment of IBS-D includes loperamide, bile acid sequestrants, antispasmodics, tricyclic antidepressants, alosetron, eluxadoline and rifaximin. The latter two treatments have significantly added to the pharmacotherapeutic options for patients suffering from IBS-D.

Effect of uptake transporters OAT3 and OATP1B1 and efflux transporter MRP2 on the pharmacokinetics of eluxadoline

The effects of OATP1B1, OAT3, and MRP2 on the pharmacokinetics of eluxadoline, an oral, locally active, opioid receptor agonist/antagonist being developed for treatment of IBS-d were assessed in vivo. Coadministration of a single 200 mg dose of eluxadoline with cyclosporine, and probenecid increased eluxadoline systemic exposure [AUC(0-inf) ] by 4.4- and 1.4-fold, respectively, whereas peak exposure (Cmax ) increased 6.2-fold and 1.3-fold, respectively. Cyclosporine had little effect on renal clearance (CLren ) of eluxadoline whereas probenecid reduced CLren by nearly 50%. These study results suggested that sinusoidal OATP1B1-mediated hepatic uptake of eluxadoline (during first-pass and systemic extraction) plays a major role in its absorption and disposition, whereas OAT3-mediated basolateral uptake in the proximal renal tubules and MRP2-mediated canalicular and renal tubular apical efflux play only minor roles in its overall disposition. All treatments were safe and well tolerated.

Current and emerging drug options in the treatment of diarrhea predominant irritable bowel syndrome

INTRODUCTION

Irritable bowel syndrome diarrhea predominant (IBS-D) is a highly prevalent GI disease, affecting nearly a third of all patients diagnosed with irritable bowel syndrome. Current treatment options are limited.

AREAS COVERED

This review discusses the pharmacotherapeutic options for IBS-D including currently used medications, the two newly FDA approved medications, as well as emerging therapies with potential benefit in IBS-D. Particular emphasis is placed on rifaximin and eluxadoline and their possible use in IBS-D.

EXPERT OPINION

Current pharmacological treatment of IBS-D includes loperamide, bile acid sequestrants, antispasmodics, tricyclic antidepressants, alosetron, eluxadoline and rifaximin. The latter two treatments have significantly added to the pharmacotherapeutic options for patients suffering from IBS-D.