Lacy, Brian E.

Summary Background MRx1234 is a live biotherapeutic product that contains a strain of Blautia hydrogenotrophica. It is in development for the treatment of irritable bowel syndrome (IBS). Aims To assess the efficacy and safety of MRx1234 in patients with IBS with predominant constipation (IBS‐C) or diarrhoea (IBS‐D) Methods We conducted a multicentre, randomised, double‐blind, placebo‐controlled, phase 2 trial. Patients aged 18–70 years in two parallel cohorts (IBS‐C; IBS‐D) were randomised (1:1) to MRx1234 or placebo for 8 weeks. The primary efficacy endpoint was overall responder rate—a composite of improved bowel habit (IBS‐C: stool frequency; IBS‐D: stool consistency) and abdominal pain intensity—for ≥50% of the treatment period in each cohort. Statistical testing was at a one‐sided 0.10 significance level. Results Of 366 randomised patients (164 IBS‐C; 202 IBS‐D), 365 received any study medication (177 MRx1234, 188 placebo). Numerically, although not statistically significantly different, more patients who received MRx1234 than placebo were overall responders in the IBS‐C (25.0% vs. 17.1%) and IBS‐D (23.4% vs. 17.8%) cohorts. Similar results were observed in the additional combined cohort analysis (24.1% vs. 17.5%; p = 0.063). For the components of the primary endpoint, significantly more patients on MRx1234 than placebo reported improvement in bowel habit in the IBS‐C, IBS‐D and combined cohorts, while improvements in abdominal pain were observed in each cohort. The safety profile of MRx1234 was similar to placebo. Conclusions MRx1234 has the potential to become a novel, safe treatment option for patients with IBS‐C or IBS‐D, and for those who have mixed symptoms or transition between subtypes. ClinicalTrials.gov #NCT03721107.

INTRODUCTION: These post hoc analyses provide clinically relevant data concerning time to response for individual irritable bowel syndrome with constipation (IBS-C) symptoms after linaclotide use. METHODS: Time-to-response data were pooled from 4 randomized controlled trials. Response time for abdominal symptoms (pain, discomfort, and bloating) and complete spontaneous bowel movements (CSBMs) were analyzed using the Kaplan-Meier method; patients were categorized as early responders (≤4 weeks), late responders (>4–12 weeks), or nonresponders. RESULTS: Among 2,350 patients (1,172 placebo and 1,178 linaclotide 290 μg), >50% of patients with IBS-C who initiated linaclotide treatment experienced a decrease of ≥30% in abdominal pain, discomfort, or bloating within 3–4 weeks (median). The median time to achieving ≥3 CSBMs was 4 weeks. Although not all linaclotide-treated patients responded within 12 weeks, a late response occurred between 4 and 12 weeks in 1 in 6 patients for abdominal pain and in approximately 1 in 10 patients for CSBM frequency. Comparisons of early responders, late responders, and nonresponders for both response definitions indicated that women, Whites, and patients with less severe baseline abdominal symptoms were more likely to respond early. DISCUSSION: Although treatment responses with linaclotide occurred in >50% of patients with IBS-C within 4 weeks of treatment initiation, benefits for individual abdominal symptoms and/or CSBM frequency can still occur between 4 and 12 weeks. A lack of improvement in one symptom does not negate the possibility of response for others, highlighting the importance of discussing all symptoms with patients and not assuming treatment futility at 4 weeks.

AbstractBackgroundPreclinical and clinical studies suggest that β3‐adrenergic receptor activation may be a novel target for treating abdominal pain and gastrointestinal motility dysfunction in patients with irritable bowel syndrome (IBS). This proof‐of‐concept study evaluated the efficacy and safety of the β3‐adrenergic agonist vibegron in treating IBS‐related pain.MethodsAdult women with predominant‐diarrhea IBS (IBS‐D) or with mixed diarrhea/constipation (IBS‐M), diagnosed using Rome IV criteria, were randomized 1:1 to receive once‐daily vibegron 75 mg or placebo for 12 weeks. The primary endpoint was the percentage of patients with IBS‐D considered abdominal pain intensity (API) weekly responders, defined as ≥30% reduction from baseline at week 12 in mean weekly worst abdominal pain over 24 hours using the API score. Patients completed a pain diary at baseline and at weeks 2, 4, 8, and 12. Safety was assessed by adverse events (AEs) in the overall IBS population.Key ResultsOf the 222 patients with IBS randomized (vibegron, N = 111; placebo, N = 111), 85% completed the trial. There was no significant difference in the percentage of patients with IBS‐D (vibegron, N = 66; placebo, N = 63) considered API weekly responders with vibegron vs. placebo (p = 0.8222) after 12 weeks. The incidence of AEs was comparable between treatment groups (33.3% each), with equal rates of worsening IBS symptoms (2.7% each).Conclusions and InferencesIn women with IBS‐D, vibegron was not associated with significant improvement in the percentage of API weekly responders. Vibegron was generally safe and well tolerated and, in particular, did not worsen IBS symptoms vs. placebo.

Constipation is a common problem, affects 15% of the population, and is often self-diagnosed and self-managed. Over the past 3 decades, there have been significant advances in our understanding and management of chronic constipation, with the emerging recognition that occasional constipation (OC) is another subtype that falls outside current classifications. The purpose of this review was to describe the process of developing and proposing a new definition for OC based on expert consensus and taking into consideration the multifactorial nature of the problem such as alterations in bowel habit that include stool frequency and difficulty with stool passage, perception of the sufferer, duration of symptoms, and potential responsiveness to treatment. Leading gastroenterologists from 5 countries met virtually on multiple occasions through an online digital platform to discuss the problem of OC and recommended a practical, user-friendly definition: “OC can be defined as intermittent or occasional symptomatic alteration(s) in bowel habit. This includes a bothersome reduction in the frequency of bowel movements and/or difficulty with passage of stools but without alarming features. Bowel symptoms may last for a few days or a few weeks, and episodes may require modification of lifestyle, dietary habits and/or use of over-the-counter laxatives or bulking agents to restore a satisfactory bowel habit.” Prospective studies are required to validate this definition and determine OC prevalence in the community. This review highlights current knowledge gaps and could provide impetus for future research to facilitate an improved understanding of OC and development of evidence-based management guidelines.

Introduction: Linaclotide is approved for adults with moderate-to-severe irritable bowel syndrome (IBS) with constipation (IBS-C). Linaclotide is not indicated for weight loss or for patients with inflammatory bowel disease (IBD); it is contraindicated in patients with mechanical bowel obstruction (MBO). Some patients with obesity or eating disorders (ED) may use linaclotide off-label for weight loss or as a laxative. Objectives: To describe the use of linaclotide in clinical practice, including patients with potential for off-label use or misuse. Methods: Post-authorization safety study conducted in three databases from the linaclotide launch date to 2017: the Clinical Practice Research Datalink in the United Kingdom (UK), the Information System for Research in Primary Care database in Spain and the linked Patient, Prescription and Causes of Death Registries in Sweden. Cohorts of patients were identified as having IBS using diagnostic and treatment codes; IBS subtypes were identified using symptoms and treatment codes; patients with obesity, ED, MBO, and IBD were identified using diagnostic codes or body mass index. Results: There were 1319, 1981, and 5081 linaclotide users from the United Kingdom, Spain, and Sweden with a median age of 45, 57, and 51 years, respectively; most were females. In the United Kingdom, Spain, and Sweden, respectively: 59.0%, 60.3%, and 31.3% of linaclotide users had an IBS diagnosis recorded, and among those, 68.8%, 61.3%, and 92.7% were classified as IBS-C. The proportions of linaclotide users considered at risk for potential off-label use for weight loss or as a laxative were 17.1%, 29.7%, and 1.7%, and the proportions of users considered at risk of misuse due to a history of MBO or IBD were 3.5%, 4.6%, and 5.7% in the United Kingdom, Spain, and Sweden, respectively. Conclusions: Potential linaclotide off-label use and misuse appears limited, as evidenced by the small sizes of the patient subgroups at risk for off-label use and misuse.

AbstractBackgroundAbdominal bloating and distension are prevalent gastrointestinal symptoms. Our aim was to design and validate a questionnaire to reliably measure the multiple symptom components of bloating and distension in the outpatient setting.MethodsA 45‐item questionnaire was developed after an extensive literature review. Face and content validity were established through expert review and a focus group. Validation was achieved by administering an identical questionnaire 1 week apart. Data were assessed using standard methods.Key resultsForty one patients returned both questionnaires (85% women; mean age = 44 years). Respondents reported a variety of diagnoses, including irritable bowel syndrome (63%), gastroesophageal reflux disease (54%), functional dyspepsia (27%), small intestinal bacterial overgrowth (22%), and gastroparesis (17%). Test‐retest reliability revealed excellent agreement (k ≥ 0.81) and substantial agreement (0.61 ≤ k < 0.81) for 29% and 43% of categorical questions, respectively. Alternate‐parallel form reliability was supported by association between responses for questions that evaluated missing school/work and questions that evaluated symptom impact on daily activities (p < 0.05). Patients who missed school/work due to bloating symptoms were more likely to report a severe impact on their ability to enjoy life (p < 0.05) and their overall well‐being (p < 0.01). Contingency analyses revealed an association between overall 7‐day symptom severity and impact on daily activities (p < 0.001), enjoying life (p < 0.001), and overall well‐being (p < 0.001).Conclusions and InferencesThis novel questionnaire demonstrated good validity and reliability in patients with symptoms of bloating and distension. The questionnaire was easy to use and score, making it a potentially useful tool for both research studies and clinical purposes.

Abstract: Disorders of gastric motor and sensory function affect 10%-20% of the world’s population and adversely impact nutrition, quality of life, work productivity, and health care costs. Classifying these disorders can be challenging given the heterogeneity of symptom presentation, the presence of symptoms unexplained by endoscopic, radiographic and/or laboratory evaluation, and overlap with other luminal gastrointestinal disorders. Accurately diagnosing these highly prevalent disorders relies upon an understanding of epidemiology and risk factors, the ability to take a careful clinical history focused on symptoms, and the presence of predisposing medical, surgical, and psychological conditions. A variety of diagnostic studies are now available to assess gastric motor function and identify maladaptive relaxation, accommodation, and abnormal sensation. FDA-approved treatment options are limited and thus many patients undergo a series of empirical treatment trials that target individual symptoms, often without much benefit. This article provides updated recommendations for identifying and classifying the most common gastric motor and sensory disorders using currently accepted diagnostic tests, and provides a brief supplemental overview on treatment options. “Things sweet to taste prove in digestion sour.” –Shakespeare, Richard II , 1595.