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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.
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Dolor Abdominal/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Imidazoles/uso terapéutico , Síndrome del Colon Irritable/tratamiento farmacológico , Fenilalanina/análogos & derivados , Dolor Abdominal/etiología , Adulto , Anciano , Diarrea/tratamiento farmacológico , Diarrea/etiología , Método Doble Ciego , Femenino , Humanos , Síndrome del Colon Irritable/complicaciones , Masculino , Persona de Mediana Edad , Fenilalanina/uso terapéutico , Resultado del TratamientoAsunto(s)
Síndrome del Colon Irritable , Diarrea , Humanos , Imidazoles , Fenilalanina/análogos & derivadosRESUMEN
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.
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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.
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Fármacos Gastrointestinales/farmacología , Corazón/fisiología , Imidazoles/farmacología , Moxifloxacino/farmacocinética , Fenilalanina/análogos & derivados , Administración Oral , Adulto , Estudios Cruzados , Electrocardiografía , Femenino , Fármacos Gastrointestinales/administración & dosificación , Voluntarios Sanos , Corazón/efectos de los fármacos , Pruebas de Función Cardíaca/efectos de los fármacos , Humanos , Imidazoles/administración & dosificación , Masculino , Persona de Mediana Edad , Moxifloxacino/administración & dosificación , Fenilalanina/administración & dosificación , Fenilalanina/farmacología , Adulto JovenAsunto(s)
Fármacos Gastrointestinales/farmacocinética , Imidazoles/farmacocinética , Hepatopatías/metabolismo , Fenilalanina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fármacos Gastrointestinales/efectos adversos , Fármacos Gastrointestinales/sangre , Fármacos Gastrointestinales/uso terapéutico , Humanos , Imidazoles/efectos adversos , Imidazoles/sangre , Imidazoles/uso terapéutico , Hepatopatías/sangre , Masculino , Persona de Mediana Edad , Fenilalanina/efectos adversos , Fenilalanina/sangre , Fenilalanina/farmacocinética , Fenilalanina/uso terapéutico , Resultado del Tratamiento , Adulto JovenRESUMEN
This corrects the article DOI: 10.1038/ajg.2017.72.
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OBJECTIVES: Irritable bowel syndrome with diarrhea (IBS-D) is often managed with over-the-counter therapies such as loperamide, though with limited success. This analysis evaluated the efficacy of eluxadoline in patients previously treated with loperamide in two phase 3 studies. METHODS: Adults with IBS-D (Rome III criteria) were enrolled and randomized to placebo or eluxadoline (75 or 100 mg) twice daily for 26 (IBS-3002) or 52 (IBS-3001) weeks. Patients reported loperamide use over the previous year and recorded their rescue loperamide use during the studies. The primary efficacy end point was the proportion of patients with a composite response of simultaneous improvement in abdominal pain and reduction in diarrhea. RESULTS: A total of 2,428 patients were enrolled; 36.0% reported prior loperamide use, of whom 61.8% reported prior inadequate IBS-D symptom control with loperamide. Among patients with prior loperamide use, a greater proportion treated with eluxadoline (75 and 100 mg) were composite responders vs. those treated with placebo with inadequate prior symptom control, over weeks 1-12 (26.3% (P=0.001) and 27.0% (P<0.001) vs. 12.7%, respectively); similar results were observed over weeks 1-26. When daily rescue loperamide use was imputed as a nonresponse day, the composite responder rate was still higher in patients receiving eluxadoline (75 and 100 mg) vs. placebo over weeks 1-12 (P<0.001) and weeks 1-26 (P<0.001). Adverse events included nausea and abdominal pain. CONCLUSIONS: Eluxadoline effectively and safely treats IBS-D symptoms of abdominal pain and diarrhea in patients who self-report either adequate or inadequate control of their symptoms with prior loperamide treatment, with comparable efficacy and safety irrespective of the use of loperamide as a rescue medication during eluxadoline treatment.
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Antidiarreicos/uso terapéutico , Fármacos Gastrointestinales/uso terapéutico , Imidazoles/uso terapéutico , Síndrome del Colon Irritable/tratamiento farmacológico , Loperamida/uso terapéutico , Fenilalanina/análogos & derivados , Dolor Abdominal/etiología , Adulto , Antidiarreicos/efectos adversos , Diarrea/etiología , Método Doble Ciego , Femenino , Fármacos Gastrointestinales/efectos adversos , Humanos , Imidazoles/efectos adversos , Síndrome del Colon Irritable/complicaciones , Loperamida/efectos adversos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Fenilalanina/efectos adversos , Fenilalanina/uso terapéutico , Evaluación de SíntomasRESUMEN
BACKGROUND & AIMS: Eluxadoline is approved by the Food and Drug Administration for the treatment of adults with irritable bowel syndrome with diarrhea (IBS-D). Eluxadoline is a locally acting mixed µ-opiod and κ-opioid receptor agonist and δ-opioid receptor antagonist. The abuse potential of eluxadoline was evaluated as part of the Phase 2 and 3 clinical trials assessing the efficacy, safety, and tolerability of the drug. METHODS: One Phase 2 (IBS-2001) and two Phase 3 (IBS-3001 and IBS-3002) randomized controlled trials enrolled patients meeting Rome III criteria for IBS-D. Patients received oral twice-daily double-blind treatment with eluxadoline or placebo for 12, 26, or 52 weeks. The primary end point of these studies was the proportion of patients who had a composite response of decrease in abdominal pain and improvement in stool consistency on the same day for at least 50% of days. Safety data were pooled, and specific adverse event terms potentially related to abuse were assessed descriptively. Adverse events reported during a 2-week post-treatment period (IBS-3001) and a 4-week single-blind washout period (IBS-3002) were assessed for signs of opioid withdrawal. Potential withdrawal effects were assessed by using the Subjective Opiate Withdrawal Scale. RESULTS: Overall, 807 and 1032 patients received 1 or more doses of eluxadoline (75 or 100 mg, respectively), and 975 patients received placebo. The overall incidence of adverse events potentially related to abuse did not differ significantly among the groups given placebo, eluxadoline 75 mg, or eluxadoline 100 mg (2.8%, 2.7%, and 4.3%, respectively). The most common adverse events potentially related to abuse were anxiety and somnolence, which occurred in less than 2% of patients in each group. Median overall Subjective Opiate Withdrawal Scale scores did not differ significantly among the groups given placebo, eluxadoline 75 mg, or eluxadoline 100 mg (3.0, 2.0, and 3.0, respectively). CONCLUSIONS: In an analysis of data from Phase 2 and Phase 3 trials of eluxadoline (75 or 100 mg) for patients with IBS-D, data revealed no signs of abuse potential for eluxadoline. ClinicalTrials.gov numbers: NCT01130272, NCT01553591, NCT01553747.
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Diarrea/tratamiento farmacológico , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/efectos adversos , Imidazoles/administración & dosificación , Imidazoles/efectos adversos , Síndrome del Colon Irritable/tratamiento farmacológico , Fenilalanina/análogos & derivados , Trastornos Relacionados con Sustancias/epidemiología , Administración Oral , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Método Doble Ciego , Humanos , Síndrome del Colon Irritable/complicaciones , Fenilalanina/administración & dosificación , Fenilalanina/efectos adversos , Placebos/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple CiegoRESUMEN
The sphincter of Oddi (SO) is a smooth muscle valve regulating the flow of biliary and pancreatic secretions into the duodenum, initially described in 1887 by the Italian anatomist, Ruggero Oddi. SO dysfunction (SOD) is a broad term referring to numerous biliary, pancreatic, and hepatic disorders resulting from spasms, strictures, and relaxation of this valve at inappropriate times. This review brings attention to various factors that may increase the risk of SOD, including but not limited to: cholecystectomy, opiates, and alcohol. Lack of proper recognition and treatment of SOD may be associated with clinical events, including pancreatitis and biliary symptoms with hepatic enzyme elevation. Pharmacologic and non-pharmacologic approaches are discussed to help recognize, prevent, and treat SOD. Future studies are needed to assess the treatment benefit of agents such as calcium-channel blockers, glyceryl trinitrate, or tricyclic antidepressants in patients with SOD.
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OBJECTIVES: Eluxadoline is a mixed µ-opioid receptor (OR) and κ-OR agonist and δ-OR antagonist, approved for the treatment of irritable bowel syndrome with diarrhea (IBS-D). This analysis evaluated the safety and tolerability of eluxadoline 75 and 100 mg twice daily (BID) in one Phase 2 (IBS-2001) and two Phase 3 (IBS-3001 and IBS-3002) studies. METHODS: Adults with IBS-D (Rome III criteria) were randomized to placebo or eluxadoline (75 or 100 mg) BID for 12 (IBS-2001), 26 (IBS-3002), or 52 (IBS-3001) weeks. Safety data were pooled. Adverse events (AEs) were assessed, with special focus on opioid-related AEs, including suspected sphincter of Oddi spasm (SOS) events. RESULTS: 2,776 patients were included in the enrolled set; the safety set comprised 2,814 patients, based on actual treatments received. The most frequent AEs in the placebo and eluxadoline 75 and 100 mg groups were constipation (2.5, 7.4, and 8.1%, respectively) and nausea (5.0, 8.1, and 7.1%, respectively); discontinuation due to constipation was uncommon (0.3, 1.1, and 1.5%, respectively). Ten SOS events (10/1,839; 0.5%) occurred in eluxadoline-treated patients, manifesting as acute abdominal pain with elevated aminotransferases or lipase, or pancreatitis; all occurred in patients without a gallbladder. Eight of these events occurred with the higher dose of eluxadoline, within 1 week of initiation of therapy, and all resolved with eluxadoline discontinuation. There were five events independently adjudicated as pancreatitis not associated with SOS, three of which were associated with heavy alcohol use. CONCLUSIONS: Eluxadoline was well tolerated in Phase 2 and 3 trials, with constipation and nausea the most common AEs. Consistent with the known adverse effects of opioid agonists, clinically apparent SOS events were observed in eluxadoline-treated patients. All occurred in patients without a gallbladder and the majority were observed in patients on the higher dose of eluxadoline, suggesting a possible association.
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Estreñimiento/inducido químicamente , Diarrea/tratamiento farmacológico , Fármacos Gastrointestinales/efectos adversos , Imidazoles/efectos adversos , Síndrome del Colon Irritable/tratamiento farmacológico , Náusea/inducido químicamente , Fenilalanina/análogos & derivados , Espasmo/inducido químicamente , Disfunción del Esfínter de la Ampolla Hepatopancreática/inducido químicamente , Dolor Abdominal/inducido químicamente , Adulto , Anciano , Diarrea/etiología , Método Doble Ciego , Femenino , Humanos , Síndrome del Colon Irritable/complicaciones , Masculino , Persona de Mediana Edad , Pancreatitis/inducido químicamente , Fenilalanina/efectos adversos , Receptores Opioides delta/antagonistas & inhibidores , Receptores Opioides kappa/agonistas , Receptores Opioides mu/agonistasRESUMEN
Background Effective and safe treatments are needed for patients who have irritable bowel syndrome (IBS) with diarrhea. We conducted two phase 3 trials to assess the efficacy and safety of eluxadoline, a new oral agent with mixed opioid effects (µ- and κ-opioid receptor agonist and δ-opioid receptor antagonist), in patients with IBS with diarrhea. Methods We randomly assigned 2427 adults who had IBS with diarrhea to eluxadoline (at a dose of 75 mg or 100 mg) or placebo twice daily for 26 weeks (IBS-3002 trial) or 52 weeks (IBS-3001 trial). The primary end point was the proportion of patients who had a composite response of decrease in abdominal pain and improvement in stool consistency on the same day for at least 50% of the days from weeks 1 through 12 and from weeks 1 through 26. Results For weeks 1 through 12, more patients in the eluxadoline groups (75 mg and 100 mg) than in the placebo group reached the primary end point (IBS-3001 trial, 23.9% with the 75-mg dose and 25.1% with the 100-mg dose vs. 17.1% with placebo; P=0.01 and P=0.004, respectively; IBS-3002 trial, 28.9% and 29.6%, respectively, vs. 16.2%; P<0.001 for both comparisons). For weeks 1 through 26, the corresponding rates in IBS-3001 were 23.4% and 29.3% versus 19.0% (P=0.11 and P<0.001, respectively), and the corresponding rates in IBS-3002 were 30.4% and 32.7% versus 20.2% (P=0.001 and P<0.001, respectively). The most common adverse events associated with 75 mg of eluxadoline and 100 mg of eluxadoline, as compared with placebo, were nausea (8.1% and 7.5% vs. 5.1%), constipation (7.4% and 8.6% vs. 2.5%), and abdominal pain (5.8% and 7.2% vs. 4.1%). Pancreatitis developed in 5 (2 in the 75-mg group and 3 in the 100-mg group) of the 1666 patients in the safety population (0.3%). Conclusions Eluxadoline is a new therapeutic agent that reduced symptoms of IBS with diarrhea in men and women, with sustained efficacy over 6 months in patients who received the 100-mg dose twice daily. (Funded by Furiex Pharmaceuticals, an affiliate of Allergan; IBS-3001 and IBS-3002 ClinicalTrials.gov numbers, NCT01553591 and NCT01553747 , respectively.).
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Diarrea/tratamiento farmacológico , Imidazoles/uso terapéutico , Síndrome del Colon Irritable/tratamiento farmacológico , Fenilalanina/análogos & derivados , Dolor Abdominal/inducido químicamente , Adulto , Anciano , Diarrea/etiología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Imidazoles/efectos adversos , Síndrome del Colon Irritable/complicaciones , Masculino , Persona de Mediana Edad , Pancreatitis/inducido químicamente , Fenilalanina/efectos adversos , Fenilalanina/uso terapéuticoRESUMEN
BACKGROUND: In previous studies, the Irritable Bowel Syndrome Quality of Life (IBS-QOL) instrument has been determined to have good measurement properties for general irritable bowel syndrome (IBS) and the diarrheal IBS (IBS-d) subtype in clinical trials. OBJECTIVE: This article aims to extend the true-score analyses that have been previously conducted to evaluate the IBS-QOL in IBS-d patients. METHODS: Item response theory analysis was conducted by fitting models to responses from 753 patients with severe IBS-d from a recent clinical trial. Three item response theory models, the constrained graded response model (CGRM), the unconstrained GRM (UGRM), and the testlet response model (TRM), were fit to the 34 items of the IBS-QOL questionnaire. Subsequently, differential item functioning (DIF) for patient sex was assessed by fitting nested models by applying likelihood ratio tests. Model latent trait estimates were then compared with the IBS-QOL score and the IBS Symptom Severity Score. RESULTS: Model fits improved with complexity, with the TRM model fitting best compared with the CGRM and UGRM. The DIF evaluation for patient sex flagged 17 items for the CGRM and 9 items for the UGRM; however, these items were not found to have much effect on the overall estimation of the latent trait. Differential testlet functioning was not indicated, and no items exhibited potential DIF under the TRM because likelihood ratio tests were not statistically significant. Comparison of latent trait estimates to the IBS Symptom Severity Score and IBS-QOL questionnaire revealed high Spearman correlations (0.47 and ≥0.99, respectively). CONCLUSION: Previous true-score approach results were supported by the IBS-QOL item-level analysis. Further, the IBS-QOL total score was found to be a valid measure of perceived quality of life for IBS-d patients when compared with more sophisticated model-based estimates of perceived quality of life. ClinicalTrials.gov identifier: NCT01130272.
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Diarrea/psicología , Síndrome del Colon Irritable/psicología , Calidad de Vida , Encuestas y Cuestionarios , Ensayos Clínicos Fase II como Asunto , Diarrea/tratamiento farmacológico , Femenino , Humanos , Imidazoles/uso terapéutico , Síndrome del Colon Irritable/tratamiento farmacológico , Síndrome del Colon Irritable/patología , Masculino , Modelos Psicológicos , Fenilalanina/análogos & derivados , Fenilalanina/uso terapéutico , PsicometríaRESUMEN
BACKGROUND: Diarrhea-predominant irritable bowel syndrome (IBS-d) significantly diminishes the health-related quality of life (HRQOL) of patients. Psychological and social impacts are common with many IBS-d patients reporting comorbid depression, anxiety, decreased intimacy, and lost working days. The Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire is a 34-item instrument developed and validated for measurement of HRQOL in non-subtyped IBS patients. The current paper assesses this previously-validated instrument employing data collected from 754 patients who participated in a randomized clinical trial of a novel treatment, eluxadoline, for IBS-d. METHODS: Psychometric methods common to HRQOL research were employed to evaluate the IBS-QOL. Many of the historical analyses of the IBS-QOL validations were used. Other techniques that extended the original methods were applied where more appropriate for the current dataset. In IBS-d patients, we analyzed the items and substructure of the IBS-QOL via item reduction, factor structure, internal consistency, reproducibility, construct validity, and ability to detect change. RESULTS: This study supports the IBS-QOL as a psychometrically valid measure. Factor analyses suggested that IBS-specific QOL as measured by the IBS-QOL is a unidimensional construct. Construct validity was further buttressed by significant correlations between IBS-QOL total scores and related measures of IBS-d severity including the historically-relevant Irritable Bowel Syndrome Adequate Relief (IBS-AR) item and the FDA's Clinical Responder definition. The IBS-QOL also showed a significant ability to detect change as evidenced by analysis of treatment effects. A minority of the items, unrelated to the IBS-d, performed less well by the standards set by the original authors. CONCLUSIONS: We established that the IBS-QOL total score is a psychometrically valid measure of HRQOL in IBS-d patients enrolled in this study. Our analyses suggest that the IBS-QOL items demonstrate very good construct validity and ability to detect changes due to treatment effects. Furthermore, our analyses suggest that the IBS-QOL items measure a univariate construct and we believe further modeling of the IBS-QOL from an item response theory (IRT) approach under both non-treatment and treatment conditions would greatly further our understanding as item-based methods could be used to develop a short form.
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Diarrea/psicología , Síndrome del Colon Irritable/psicología , Calidad de Vida/psicología , Encuestas y Cuestionarios/normas , Adolescente , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Análisis Factorial , Femenino , Humanos , Síndrome del Colon Irritable/tratamiento farmacológico , Síndrome del Colon Irritable/fisiopatología , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Psicometría , Ensayos Clínicos Controlados Aleatorios como Asunto , Estados Unidos , Adulto JovenAsunto(s)
Antibacterianos/uso terapéutico , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Fluoroquinolonas/uso terapéutico , Neumonía Bacteriana/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacterias/clasificación , Bacterias/aislamiento & purificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND & AIMS: Simultaneous agonism of the µ-opioid receptor and antagonism of the δ-opioid receptor can reduce abdominal pain and diarrhea in patients with irritable bowel syndrome with diarrhea (IBS-D) without constipating side effects. We evaluated the efficacy and safety of a minimally absorbed, µ-opioid receptor agonist and δ-opioid receptor antagonist (eluxadoline) in a phase 2 study in patients with IBS-D. METHODS: We randomly assigned 807 patients to groups that received oral placebo twice daily or 5, 25, 100, or 200 mg oral eluxadoline for 12 weeks. The primary end point was clinical response at week 4, defined by a mean reduction in daily pain score from baseline of ≥ 30%, and of at least 2 points on 0-10 scale, as well as a stool consistency score of 3 or 4 on the Bristol Stool Scale (1-7) for at least 66% of daily diary entries during that week. RESULTS: Significantly more patients receiving 25 mg (12.0%) or 200 mg (13.8%) eluxadoline met the primary end point of clinical response than patients given placebo (5.7%; P < .05). Patients receiving eluxadoline at 100 mg and 200 mg also had greater improvements in bowel movement frequency and urgency, global symptoms, quality of life, and adequate relief assessments (P < .05). Additionally, patients receiving 100 mg (28.0%) or 200 mg (28.5%) eluxadoline were significantly more likely than those receiving placebo (13.8%; P < .005) to meet the US Food and Drug Administration response end point during the full 12 weeks of the study. Eluxadoline was well tolerated with a low incidence of constipation. CONCLUSIONS: In a phase 2 study of the mixed µ-opioid receptor agonist/δ-opioid receptor antagonist eluxadoline vs placebo in patients with IBS-D, patients given eluxadoline were significantly more likely to be clinical responders, based on a composite of improvement in abdominal pain and stool consistency. Further study of eluxadoline is warranted to assess its potential as a treatment for IBS-D.