Randomised clinical trial: otilonium bromide improves frequency of abdominal pain, severity of distention and time to relapse in patients with irritable bowel syndrome

Pamoic acid and carbenoxolone specifically inhibit CRISPR/Cas9 in bacteria, mammalian cells, and mice in a DNA topology-specific manner

BACKGROUND

Regulation of the target DNA cleavage activity of CRISPR/Cas has naturally evolved in a few bacteria or bacteriophages but is lacking in higher species. Thus, identification of bioactive agents and mechanisms that can suppress the activity of Cas9 is urgently needed to rebalance this new genetic pressure.

RESULTS

Here, we identify four specific inhibitors of Cas9 by screening 4607 compounds that could inhibit the endonuclease activity of Cas9 via three distinct mechanisms: substrate-competitive and protospacer adjacent motif (PAM)-binding site-occupation; substrate-targeting; and sgRNA-targeting mechanisms. These inhibitors inhibit, in a dose-dependent manner, the activity of Streptococcus pyogenes Cas9 (SpyCas9), Staphylococcus aureus Cas9 (SauCas9), and SpyCas9 nickase-based BE4 base editors in in vitro purified enzyme assays, bacteria, mammalian cells, and mice. Importantly, pamoic acid and carbenoxolone show DNA-topology selectivity and preferentially inhibit the cleavage of linear DNA compared with a supercoiled plasmid.

CONCLUSIONS

These pharmacologically selective inhibitors and new mechanisms offer new tools for controlling the DNA-topology selective activity of Cas9.

Randomized clinical trial: A phase 2b controlled study of the efficacy and safety of trazpiroben (TAK-906) for idiopathic or diabetic gastroparesis

BACKGROUND

Previous clinical studies of trazpiroben, a dopamine D2 /D3 receptor antagonist for long-term treatment of moderate-to-severe idiopathic and diabetic gastroparesis, have shown improved symptoms of fullness. This study assessed trazpiroben efficacy, safety, and tolerability in adults with idiopathic and diabetic gastroparesis versus placebo.

METHODS

This global, multicenter, double-blind, parallel-group, phase 2b study (NCT03544229) enrolled eligible adults aged 18-85 years with symptomatic idiopathic or diabetic gastroparesis. Randomized participants received either oral placebo or trazpiroben 5, 25, or 50 mg, administered twice daily over 12 weeks, and completed the American Neurogastroenterology and Motility Society Gastroparesis Cardinal Symptom Index-Daily Diary. Change in weekly composite score from baseline to week 12 (primary endpoint) and treatment-emergent adverse events were assessed. Data were summarized descriptively.

KEY RESULTS

Overall, 242 participants were enrolled (mean [standard deviation] age 55.7 [14.2] years; 75.6% female); 193 completed the study. No significant differences in change from baseline in weekly average of the daily diary composite score occurred at week 12 between placebo (least-squares mean [standard error] -1.19 [0.12]) and trazpiroben (5, 25, and 50 mg: -1.11 [0.22], -1.17 [0.12], and -1.21 [0.12], respectively). Overall, 41.4% of participants receiving trazpiroben reported treatment-emergent adverse events (placebo, 39.7%). No serious events were considered trazpiroben-related; no life-threatening or fatal events were reported.

CONCLUSIONS & INFERENCES

There was no clinically meaningful difference in efficacy between trazpiroben and placebo in treating gastroparesis, based on the primary endpoint analysis. Trazpiroben was well tolerated with no new safety concerns identified, strengthening evidence supporting its favorable safety profile. NCT number: NCT03544229.

Efficacy and safety of olorinab, a full agonist of the cannabinoid receptor 2, for the treatment of abdominal pain in patients with irritable bowel syndrome: Results from a phase 2b randomized placebo-controlled trial (CAPTIVATE)

BACKGROUND

Olorinab is a highly selective, peripherally acting, full agonist of cannabinoid receptor 2. This study assessed the efficacy and safety of olorinab to treat abdominal pain in patients with irritable bowel syndrome with diarrhea (IBS-D) and constipation (IBS-C).

METHODS

CAPTIVATE was a phase 2b, randomized, double-blind, placebo-controlled, parallel-group trial. Eligible participants aged 18-70 years with IBS-C and IBS-D diagnosed per Rome IV received olorinab 10 mg, 25 mg, or 50 mg three times daily (TID) or placebo TID for 12 weeks. The primary endpoint was the change in patient-reported average abdominal pain score (AAPS) from baseline to Week 12.

KEY RESULTS

A total of 273 participants were randomized to receive olorinab 10 mg (n = 67), olorinab 25 mg (n = 67), olorinab 50 mg (n = 69), or placebo (n = 70). Although a treatment response was observed across all groups, the weekly change in average AAPS from baseline to Week 12 was not significantly different between placebo and any olorinab dose. In a prespecified subgroup analysis of participants with a baseline AAPS ≥6.5, olorinab 50 mg (n = 35) significantly improved AAPS compared with placebo (n = 30) (p = 0.014). Adverse event rates were comparable between olorinab and placebo and there were no reported serious adverse events or deaths.

CONCLUSION AND INFERENCES

Although olorinab was well-tolerated and improved weekly AAPS, the primary endpoint was not met. However, in participants with moderate-to-severe pain at baseline (AAPS ≥6.5), olorinab 50 mg significantly improved weekly AAPS compared with placebo.

CLINICALTRIALS

gov: NCT04043455.

Update on treatment of abdominal pain in irritable bowel syndrome: A narrative review

The objectives of this narrative review are to update readers on the current state-of-the-art regarding diverse approaches for the treatment of pain, global symptoms, or adequate relief in irritable bowel syndrome (IBS). The article appraises medications, dietary interventions including low fermentable oligosaccharides, disaccharides, and monosaccharides and polyols (FODMAP) diet, fecal microbial transplantation (FMT), electrical approaches, and behavioral therapies including cognitive behavioral therapy (CBT), gut-directed hypnotherapy (GDH), mindfulness, and open-label placebo. Current evidence demonstrates only modest benefit in global IBS symptoms and pain relief. A future approach that identifies pathophysiological mechanisms of IBS through validated biomarkers has the potential to individualize treatment of patients rather than sequential therapeutic trial and error approaches.

Therapeutic potential of otilonium bromide against Vibrio vulnificus

New drugs are urgently required for the treatment of infections due to an increasing number of new strains of diseases-causing pathogens and antibiotic-resistant bacteria. A library of drugs approved by Food and Drug Administration was screened for efficacy against Vibrio vulnificus using antimicrobial assays. We found that otilonium bromide showed potent antimicrobial activity against V.vulnificus and had a synergistic effect in combination with antibiotics. Field emission transmission electron microscope images revealed that otilonium bromide caused cell division defects in V.vulnificus. Moreover, it significantly inhibited V.vulnificus swarming motility and adhesion to host cells at concentrations lower than the minimum inhibitory concentration. To investigate its inhibitory action mechanisms, we examined the effect of otilonium bromide on the expression levels of several proteins crucial for V.vulnificus growth, motility, and adhesion. It decreased the protein expression levels of cAMP receptor protein and flagellin B, but not HlyU or OmpU. In addition, otilonium bromide significantly decreased the expression levels of outer membrane protein TolCV1, thus inhibiting RtxA1 toxin secretion and substantially reducing V.vulnificus cytotoxicity to host cells. Collectively, these findings suggest that otilonium bromide may be considered as a promising candidate for treating V.vulnificus infections.

Multi-omics for biomarker approaches in the diagnostic evaluation and management of abdominal pain and irritable bowel syndrome: what lies ahead

Reliable biomarkers for common disorders of gut-brain interaction characterized by abdominal pain, including irritable bowel syndrome (IBS), are critically needed to enhance care and develop individualized therapies. The dynamic and heterogeneous nature of the pathophysiological mechanisms that underlie visceral hypersensitivity have challenged successful biomarker development. Consequently, effective therapies for pain in IBS are lacking. However, recent advances in modern omics technologies offer new opportunities to acquire deep biological insights into mechanisms of pain and nociception. Newer methods for large-scale data integration of complementary omics approaches have further expanded our ability to build a holistic understanding of complex biological networks and their co-contributions to abdominal pain. Here, we review the mechanisms of visceral hypersensitivity, focusing on IBS. We discuss candidate biomarkers for pain in IBS identified through single omics studies and summarize emerging multi-omics approaches for developing novel biomarkers that may transform clinical care for patients with IBS and abdominal pain.

Diet or medication in primary care patients with IBS: the DOMINO study - a randomised trial supported by the Belgian Health Care Knowledge Centre (KCE Trials Programme) and the Rome Foundation Research Institute

BACKGROUND

In Europe, IBS is commonly treated with musculotropic spasmolytics (eg, otilonium bromide, OB). In tertiary care, a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet provides significant improvement. Yet, dietary treatment remains to be explored in primary care. We evaluated the effect of a smartphone FODMAP-lowering diet application versus OB on symptoms in primary care IBS.

METHODS

IBS patients, recruited by primary care physicians, were randomised to 8 weeks of OB (40 mg three times a day) or diet and followed for 24 weeks. We compared IBS Symptom Severity Score and the proportion of responders (improvement ≥50 points) in all patients and the subgroup fulfilling Rome IV criteria (Rome+). We also evaluated treatment efficacy, quality of life, anxiety, depression, somatic symptom severity (Patient Health Questionnaire (PHQ15, PHQ9)) and treatment adherence and analysed predictors of response.

RESULTS

459 primary care IBS patients (41±15 years, 76% female, 70% Rome+) were randomised. The responder rate after 8 weeks was significantly higher with diet compared with OB (71% (155/218) vs 61% (133/217), p=0.03) and more pronounced in Rome+ (77% (118/153) vs 62% (98/158), p=0.004). Patients allocated to diet (199/212) were 94% adherent compared with 73% with OB (148/202) (p<0.001). The significantly higher response rate with diet was already observed after 4 weeks (62% (132/213) vs 51% (110/215), p=0.02) and a high symptom response persisted during follow-up. Predictors of response were female gender (OR=2.08, p=0.04) for diet and PHQ15 (OR=1.10, p=0.02) for OB.

CONCLUSION

In primary care IBS patients, a FODMAP-lowering diet application was superior to a spasmolytic agent in improving IBS symptoms. A FODMAP-lowering diet should be considered the first-line treatment for IBS in primary care.

TRIAL REGISTRATION NUMBER

NCT04270487.

Antispasmodics

Antispasmodics are effective in reducing abdominal pain associated with visceral organs, bloating, and bowel habit changes and are commonly used as “on-demand therapy.” A relatively regular intake of antispasmodics may help patients with functional gastrointestinal disease exacerbation. Irritable bowel syndrome and functional dyspepsia are representative functional gastrointestinal diseases with abdominal pain and bloating as the main symptoms. Most of the clinical data on antispasmodics are obtained from studies on functional gastrointestinal diseases including irritable bowel syndrome. Antispasmodics can be safely used for prolonged periods without serious adverse effects; however, different antispasmodics have different anticholinergic potencies. Antispasmodics with strong anticholinergic effects should be prescribed with caution to patients with glaucoma or prostatic hypertrophy-induced dysuria and to those driving vehicles, operating machinery, or receiving other anticholinergic drugs in combination. Antispasmodics meeting US Food and Drug Administration guidelines for efficacy, those showing relatively consistent efficacy in different trials, and those with prokinetic effects are currently available. Many patients with upper gastrointestinal symptoms have overlapping functional gastrointestinal disorders and may require antispasmodic drugs. Alternatively, tricyclic antidepressant or ramosetron use can be considered in patients with irritable bowel syndrome. This review summarizes the clinical data and characteristics of antispasmodics, particularly those available in South Korea.

Belgian consensus on irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is characterised by recurrent abdominal pain related to defaecation or associated with altered stool frequency or consistency. Despite its prevalence, major uncertainties in the diagnostic and therapeutic management persist in clinical practice.

METHODS

A Delphi consensus was conducted by 20 experts from Belgium, and consisted of literature review and voting process on 78 statements. Grading of recommendations, assessment, development and evaluation criteria were applied to evaluate the quality of evidence. Consensus was defined as > 80 % agreement.

RESULTS

Consensus was reached for 50 statements. The Belgian consensus agreed as to the multifactorial aetiology of IBS. According to the consensus abdominal discomfort also represents a cardinal symptom, while bloating and abdominal distension often coexist. IBS needs subtyping based on stool pattern. The importance of a positive diagnosis, relying on history and clinical examination is underlined, while additional testing should remain limited, except when alarm features are present. Explanation of IBS represents a crucial part of patient management. Lifestyle modification, spasmolytics and water-solube fibres are considered first-line agents. The low FODMAP diet, selected probiotics, cognitive behavioural therapy and specific treatments targeting diarrhoea and constipation are considered appropriate. There is a consensus to restrict faecal microbiota transplantation and gluten-free diet, while other treatments are strongly discouraged.

CONCLUSIONS

A panel of Belgian gastroenterologists summarised the current evidence on the aetiology, symptoms, diagnosis and treatment of IBS with attention for the specificities of the Belgian healthcare system.

Antispasmodics for Chronic Abdominal Pain: Analysis of North American Treatment Options

Chronic abdominal pain is a common gastrointestinal (GI) symptom that characterizes many functional GI disorders/disorders of gut-brain interaction, including irritable bowel syndrome, functional dyspepsia, and centrally mediated abdominal pain syndrome. The symptoms of abdominal pain in these highly prevalent disorders are often treated with antispasmodic agents. Antispasmodic treatment includes a broad range of therapeutic classes with different mechanisms of action, including anticholinergic/antimuscarinic agents (inhibition of GI smooth muscle contraction), calcium channel inhibitors (inhibition of calcium transport into GI smooth muscle), and direct smooth muscle relaxants (inhibition of sodium and calcium transport). The aim of this review article was to examine the efficacy and safety of antispasmodics available in North America (e.g., alverine, dicyclomine, hyoscine, hyoscyamine, mebeverine, otilonium, pinaverium, and trimebutine) for the treatment of chronic abdominal pain in patients with common disorders of gut-brain interaction. For the agents examined, comparisons of studies are limited by inconsistencies in treatment dosing and duration, patient profiles, and diagnostic criteria employed. Furthermore, variability in study end points limits comparisons. Risk of selection, performance, detection, attrition, and reporting bias also differed among studies, and in many cases, risks were considered "unclear." The antispasmodics evaluated in this review, which differ in geographic availability, were found to vary dramatically in efficacy and safety. Given these caveats, each agent should be considered on an individual basis, rather than prescribed based on information across the broad class of agents.

Chinese herbal medicine versus antispasmodics in the treatment of irritable bowel syndrome: A network meta-analysis

BACKGROUND

Chinese herbal medicine (CHM) is gaining popularity in treating irritable bowel syndrome (IBS). Although its efficacy was shown in recent randomized controlled trials (RCTs), it is rarely compared with antispasmodics to confirm its effectiveness. We aimed to resolve this uncertainty through a network meta-analysis.

METHODS

We searched for RCTs that compared CHM or antispasmodics with placebo or one of them in the treatment of IBS. The primary outcomes were adequate relief of global IBS symptoms and abdominal pain. The data were pooled using a random-effects model. The effect size measure was pooled relative risk (RR), and treatments were ranked according to their P-scores.

KEY RESULTS

We included 57 RCTs (n = 8869). After completion of treatment, drotaverine, individual CHM, otilonium, cimetropium, standard CHM, and pinaverium were efficacious in adequate relief of global IBS symptoms, and drotaverine ranked the first (RR, 2.33 [95% CI, 1.31-4.14], P-score =0.91); no difference was found between these treatments. After completion of treatment, drotaverine, standard CHM, pinaverium, and individual CHM were efficacious in abdominal pain, and drotaverine ranked the first (RR, 2.71 [95% CI, 1.69-4.36], P-score =0.91); no difference was found between these treatments. Standard CHM had significantly more adverse events than placebo (RR, 1.82 [95% CI, 1.12-2.94]) and other treatments.

CONCLUSIONS

CHM and antispasmodics were efficacious for improvement of global IBS symptoms and abdominal pain. The adverse events of CHM were higher than antispasmodics; however, the heterogeneity of CHM formulas and the very low quality of the evidence warrants further investigation.

IBS Therapeutic has Broad Spectrum Antimicrobial Activity

Otilonium bromide is a poorly absorbed oral medication used to control irritable bowel syndrome. It is thought to act as a muscle relaxant in the intestine. Here we show that otilonium bromide has broad-spectrum antibacterial and antifungal activity, including against multi-drug resistant strains. Our results suggest otilonium bromide could act on enteric pathogens and may offer a new scaffold for poorly absorbed intestinal antimicrobial therapy.

Assessing the post-treatment therapeutic effect of pinaverium in irritable bowel syndrome: a randomized controlled trial

Irritable bowel syndrome (IBS) is the most common gastrointestinal disorder significantly decreasing patients' lives of quality and placing huge economic burden on our society. Existing studies indicated that the therapeutic effects maintained for a period of time after the treatments were discontinued. It is clinically important to assess these post-treatment therapeutic effects (PTTE), which prevent IBS from relapsing. To assess the PTTE in pinaverium treatment and obtain high-quality evidence to justify the use of PTTE for long-term IBS management, we performed this controlled, double blind study on patients with IBS who were randomized to pinaverium 50 mg (n = 132) or placebo (n = 132), three times daily, for 4 weeks, and were followed up for 57 weeks after the treatments. The primary endpoints were abdominal pain and stool consistency. The secondary endpoints were pain frequency and stool frequency. The tertiary endpoints were global overall symptom and adverse events. Three days after pinaverium was discontinued, endpoints rebounded only 23.2-42.8% (P < 0.015 cf. placebo). The PTTE (P < 0.05 cf. placebo) lasted 9-17 weeks, which is similar to other antispasmodics with a 15-week treatment in striking contrast to ≥ 1 year PTTE in cognitive behavior therapy and < 1 week PTTE in serotonin antagonist treatment indicating that PTTE length markedly depends on the medication class used for the treatment and less depends on treatment length. After 17 weeks, the stage could be considered as an IBS natural history [no significant differences between pinaverium and placebo (all endpoints' P's > 0.05)], during which an average of 51.5-56.4% of patients (pool pinaverium and placebo data together) had IBS symptoms. These results provide clinical insights into efficient and cost-effective management of refractory IBS, and lend support to the IBS management that the selection of a therapy should consider both its effectiveness during treatment and its PTTE after the treatment.Trial registration number: NCT02330029 (16/08/2016).

Otilonium Bromide treatment prevents nitrergic functional and morphological changes caused by chronic stress in the distal colon of a rat IBS model

Irritable bowel syndrome (IBS) is a highly prevalent gastrointestinal disorder characterized by periods of remission and exacerbation. Among the risk factors to develop IBS, psychosocial stress is widely acknowledged. The water avoidance stress repeatedly applied (rWAS) is considered effective to study IBS etio-pathogenesis. Otilonium bromide (OB), a drug with multiple mechanisms of action, is largely used to treat IBS patients. Orally administered, it concentrates in the large bowel and significantly ameliorates the IBS symptomatology. Presently, we tested whether rWAS rats developed neuro-muscular abnormalities in the distal colon and whether OB treatment prevented them. The investigation was focussed on the nitrergic neurotransmission by combining functional and morphological methodologies. The results confirm rWAS as reliable animal model to investigate the cellular mechanisms responsible for IBS: exposure to one-hour psychosocial stress for 10 days depressed muscle contractility and increased iNOS expression in myenteric neurons. OB treatment counteracted these effects. We hypothesize that these effects are due to the corticotropin-releasing factor (CRF) release, the main mediator of the psychosocial stress, followed by a CRF1receptor activation. OB, that was shown to prevent CRF1r activation, reasonably interrupted the cascade events that bring to the mechanical and immunohistochemical changes affecting rWAS rat colon.

The placebo response rate in pharmacological trials in patients with irritable bowel syndrome: a systematic review and meta-analysis

BACKGROUND

Clinical trials in irritable bowel syndrome are associated with high placebo response rates. We aimed to identify the magnitude of the placebo response and the contributing factors to this occurrence.

METHODS

We did a systematic review and meta-analysis with a search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials between April 1, 1959, and April 30, 2020. We included all randomised controlled trials that compared an active pharmacotherapeutic agent with placebo and had a dichotomous outcome of response to therapy (in terms of global improvement or improvement in abdominal pain) in adults (aged ≥18 years) with irritable bowel syndrome. Exclusion criteria were trials reporting on treatment satisfaction as a dichotomous outcome of response to therapy or clinician-reported outcomes and a treatment duration of less than 4 weeks. Our main outcome was identification of the magnitude of the pooled placebo response rate for the following endpoints: global improvement, abdominal pain, and US Food and Drug Administration (FDA) endpoints. We extracted information from published reports and pooled proportions through meta-analysis with random effects. The study was registered with PROSPERO, CRD42020170908.

FINDINGS

Of the 6863 publications identified, 70 articles describing 73 randomised controlled trials were included in our analysis. The pooled placebo response rate was 27·3% (95% CI 24·3-30·9) using the global improvement endpoint, 34·4% (31·2-37·8) using the abdominal pain endpoint, and 17·9% (15·2-21·0) using the composite FDA endpoint responder definition, all with substantial heterogeneity between the trials. Studies published before 2006, and those done in Europe, with a parallel design, a run-in period of 2 weeks or less, a dose schedule of three times a day or more, or a smaller sample size of the control group were significantly associated with an increased pooled placebo response rate.

INTERPRETATION

More than a quarter of patients with irritable bowel syndrome had a placebo response in terms of global improvement, with multiple associated moderators. We recommend future trials apply a run-in period of at least 2 weeks and dose once or twice a day to minimise the placebo response rate.

FUNDING

None.

Pharmacological Therapies and Their Clinical Targets in Irritable Bowel Syndrome With Diarrhea

Irritable bowel syndrome (IBS) is one of the most common disorders of the gut-brain axis, which affects approximately 4% of the global population. The Rome IV criteria define IBS as chronic or recurrent abdominal pain associated with altered bowel habits. Patients can be categorized in four subtypes: IBS with predominant constipation (IBS-C), predominant diarrhea (IBS-D), mixed bowel habits (IBS-M), and unclassified (IBS-U). IBS is associated with a lower quality of life, reduced work productivity, and high healthcare costs. When comparing subtypes, patients with IBS-D report lower disease related quality of life. Due to the scope of this review, we have solely focused on patients with IBS-D. Choosing the right pharmacological treatment in these patients remains challenging due to the heterogeneous patient population, patients' expectation of the treatment outcome, unavailability of efficacious drugs, and the multifactorial and incompletely understood underlying pathophysiology. Currently, pharmacological treatment options target individual symptoms, such as abdominal pain, altered bowel habits, and bloating. In this review, we aimed to summarize the current and recent pharmacological treatment options in IBS-D, targeting the predominant gastrointestinal symptoms. Additionally, we proposed a pharmacological treatment algorithm which healthcare professionals could use when treating individual patients with IBS-D.

Efficacy of psychological therapies for irritable bowel syndrome: systematic review and network meta-analysis

OBJECTIVES

National guidelines for the management of irritable bowel syndrome (IBS) recommend that psychological therapies should be considered, but their relative efficacy is unknown, because there have been few head-to-head trials. We performed a systematic review and network meta-analysis to try to resolve this uncertainty.

DESIGN

We searched the medical literature through January 2020 for randomised controlled trials (RCTs) assessing efficacy of psychological therapies for adults with IBS, compared with each other, or a control intervention. Trials reported a dichotomous assessment of symptom status after completion of therapy. We pooled data using a random effects model. Efficacy was reported as a pooled relative risk (RR) of remaining symptomatic, with a 95% CI to summarise efficacy of each comparison tested, and ranked by therapy according to P score.

RESULTS

We identified 41 eligible RCTs, containing 4072 participants. After completion of therapy, the psychological interventions with the largest numbers of trials, and patients recruited, demonstrating efficacy included self-administered or minimal contact cognitive behavioural therapy (CBT) (RR 0.61; 95% CI 0.45 to 0.83, P score 0.66), face-to-face CBT (RR 0.62; 95% CI 0.48 to 0.80, P score 0.65) and gut-directed hypnotherapy (RR 0.67; 95% CI 0.49 to 0.91, P score 0.57). After completion of therapy, among trials recruiting only patients with refractory symptoms, group CBT and gut-directed hypnotherapy were more efficacious than either education and/or support or routine care, and CBT via the telephone, contingency management, CBT via the internet and dynamic psychotherapy were all superior to routine care. Risk of bias of trials was high, with evidence of funnel plot asymmetry; the efficacy of psychological therapies is therefore likely to have been overestimated.

CONCLUSIONS

Several psychological therapies are efficacious for IBS, although none were superior to another. CBT-based interventions and gut-directed hypnotherapy had the largest evidence base and were the most efficacious long term.

TRIAL REGISTRATION NUMBER

The study protocol was published on the PROSPERO international prospective register of systematic reviews (registration number CRD 42020163246).

An update on efficacy and safety considerations for the latest drugs used to treat irritable bowel syndrome

INTRODUCTION

Irritable bowel syndrome (IBS), globally affecting 11.2% of the population and imposing a direct annual cost of $1.7bn-$10bn in the US, is one of the today's major therapeutic challenges. Therefore, there is urgent need to address this issue through reviewing the tolerability and efficacy of available medications.

AREAS COVERED

Over the past decade, related experiments were cited through Clinicaltrials.gov, PubMed, WHO ICTRP, and Cochrane library. Pharmacological parameters of approved medications available in the USFDA, EMA, TGA and PMDA were also stated.

EXPERT OPINION

Anti-spasmodics are used as the first-line treatment in pain-predominant IBS and IBS-D, among which calcium channel blockers and neurokinin-type 2 receptor antagonists seem to replace anti-cholinergic drugs. As second-line treatments, rifaximin is considered to be the best for IBS-D though it has lower efficacy than alosetron and eluxadoline. For IBS-C, linaclotide is the most effective and the safest second-line therapy, following laxatives/fibers, which may be replaced by tenapanor, in the future. When moderate to severe IBS is associated with severe pain or comorbid psychological disorders, gut-brain neuromodulators could also be prescribed. Regarding all this, there is still a paramount need to conduct careful clinical studies on efficacy, safety and cost-effectiveness of current approved and non-approved treatments.

The Effect of Phloroglucinol in Patients With Diarrhea-predominant Irritable Bowel Syndrome: A Randomized, Double-blind, Placebo-controlled Trial

BACKGROUND/AIMS

We aim to evaluate the efficacy and safety of phloroglucinol in patients with diarrhea-predominant irritable bowel syndrome (IBS-D).

METHODS

Seventy-two patients with IBS-D who met Rome III criteria were 1:1 randomized in a parallel, double-blind design to receive phloroglucinol or placebo for 2 weeks. Patients were followed for 1 week after the end of treatment. The primary outcome was the proportion of responders, defined as those who answered "moderate or more of improvement" to the subject global assessment for at least 1 week of the 2-week treatment period. Secondary outcomes included the proportion of these patients during the 3-week period including 1 week of follow-up, IBS symptoms (abdominal pain/discomfort, diarrhea, urgency, mucus in stool, bloating, and passage of gas), stool frequency and consistency, and IBS quality of life (IBS-QOL).

RESULTS

The proportion of responders during 2-week treatment period tended to be higher in the phloroglucinol group than in the placebo group, although the difference did not reach statistical significance (55.6% vs 30.6%, P = 0.056). The proportion of responders during the 3-week period was significantly higher in the phloroglucinol group than in the placebo group (61.6% vs 30.6%, P = 0.013). Individual symptom scores, IBS-QOL, stool frequency and consistency tended to improve in the phloroglucinol group, but there were no statistical significances compared to those of the placebo group. No serious adverse events were reported in both groups.

CONCLUSIONS

Phloroglucinol could be a safe and beneficial option for the management of overall IBS symptoms in patients with IBS-D. Further large scaled studies are warranted.

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.

Effect of Samryungbaekchul-san Combined with Otilonium Bromide on Diarrhea-Predominant Irritable Bowel Syndrome: A Pilot Randomized Controlled Trial

Conventional and herbal drugs are frequently used together to treat many disorders. Samryungbaekchul-san (SRS, a herbal formula) and otilonium bromide (OB, an antispasmodic agent) are widely used to treat diarrhea-predominant irritable bowel syndrome (D-IBS) in Eastern Asian countries. However, there have been no studies on the co-administration of SRS and OB. Therefore, we aimed to preliminarily assess the feasibility of SRS combined with OB for D-IBS treatment in a pilot double-blind, four-arm, parallel-group, randomized controlled trial (RCT), including 80 patients diagnosed with D-IBS according to the Rome III criteria. The patients were randomly assigned to four treatment groups and were administered drugs for eight weeks after a two-week preparatory period. Follow-up was conducted four weeks after the administration period. The primary outcome was evaluated by using a global D-IBS symptom improvement score; no statistically significant difference was observed between the groups. However, multiple logistic regression analysis of primary outcome scores shows that SRS significantly improved D-IBS symptoms (p < 0.05). For secondary outcomes, better results were observed in the SRS + OB group, in terms of symptoms, including abdominal pain, discomfort, frequency of abdominal pain, and stool form than in OB alone or placebo groups (p < 0.05). In conclusion, the co-administration of SRS and OB might be an effective and safe strategy for the treatment of D-IBS. Large-scale RCTs are warranted to further confirm and clarify these findings.

Canadian Association of Gastroenterology Clinical Practice Guideline for the Management of Irritable Bowel Syndrome (IBS)

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal (GI) disorders, affecting about 10% of the general population globally. The aim of this consensus was to develop guidelines for the management of IBS.

METHODS

A systematic literature search identified studies on the management of IBS. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach. Statements were developed through an iterative online platform and then finalized and voted on by a multidisciplinary group of clinicians and a patient.

RESULTS

Consensus was reached on 28 of 31 statements. Irritable bowel syndrome is diagnosed based on symptoms; serological testing is suggested to exclude celiac disease, but routine testing for C-reactive protein (CRP), fecal calprotectin or food allergies is not recommended. A trial of a low fermentable oligosaccharides, disaccharides, monosaccharides, polyols (FODMAP) diet is suggested, while a gluten-free diet is not. Psyllium, but not wheat bran, supplementation may help reduce symptoms. Alternative therapies such as peppermint oil and probiotics are suggested, while herbal therapies and acupuncture are not. Cognitive behavioural therapy and hypnotherapy are suggested psychological therapies. Among the suggested or recommended pharmacological therapies are antispasmodics, certain antidepressants, eluxadoline, lubiprostone, and linaclotide. Loperamide, cholestyramine and osmotic laxatives are not recommended for overall IBS symptoms. The nature of the IBS symptoms (diarrhea-predominant or constipation-predominant) should be considered in the choice of pharmacological treatments.

CONCLUSIONS

Patients with IBS may benefit from a multipronged, individualized approach to treatment, including dietary modifications, psychological and pharmacological therapies.

Irritable bowel syndrome: How to improve decision making in clinical practice

Irritable bowel syndrome (IBS) is a highly prevalent functional disorder, characterised by the presence of recurrent abdominal pain associated with changes in bowel habits. Its physiopathology is complex, its clinical manifestations are diverse, and the therapeutic possibilities are multiple and not well known. In clinical practice, the diagnosis of IBS represents an important challenge; this means that in many cases the patients do not receive the proper diagnosis, which implies an absence of a targeted treatment, and therefore bad symptomatic control. In this article, the fundamental questions posed by the doctor when dealing with a patient with symptoms compatible with IBS are presented chronologically. The main objective is to provide clinical and eminently practical information that facilitates the management of patients with IBS, from both diagnostic and therapeutic points of view.

Guidelines on the management of irritable bowel syndrome: In memory of Professor Witold Bartnik

These guidelines constitute an update of the previous "Recommendations on the management of irritable bowel syndrome" issued in 2008. They have been developed by a Task Force organized by the Governing Board of the Polish Society of Gastroenterology. They discuss, with particular emphasis on new scientific data covering papers published since 2008, the aetiology, epidemiology, clinical presentation, diagnostic principles and criteria for the diagnosis, and recommendations for the treatment of irritable bowel syndrome (IBS). The English-language acronym for the syndrome (IBS) has become popular in medical and popular scientific language. It is also widely recognized by patients who identify with this diagnosis. Therefore, in the discussed guidelines, this is what we will use.

Chronic abdominal pain in irritable bowel syndrome - current and future therapies

INTRODUCTION

Irritable bowel syndrome (IBS) is a functional gut disorder that typically manifests in early adult years. One of the two major symptoms of the disease is chronic, visceral pain. The patients report pain as the most distressing symptom with the greatest impact on quality of life, challenging both to patients and healthcare providers. Areas covered: This review focuses on the pathophysiology of abdominal pain in IBS and describes current treatment possibilities. It also covers latest findings that may lead to novel pharmacological options in IBS pain management. Expert commentary: Pain is the main contributor to severity in IBS. Seeking pain alleviation is the most common reason that IBS sufferers consult with their physicians. Not all patients report being satisfied with available treatments for pain in IBS and there is a pressing need to find new, more efficient therapies for this syndrome.

Clinical Practice Guidelines for Irritable Bowel Syndrome in Korea, 2017 Revised Edition

In 2011, the Korean Society of Neurogastroenterology and Motility (KSNM) published clinical practice guidelines on the management of irritable bowel syndrome (IBS) based on a systematic review of the literature. The KSNM planned to update the clinical practice guidelines to support primary physicians, reduce the socioeconomic burden of IBS, and reflect advances in the pathophysiology and management of IBS. The present revised version of the guidelines is in continuity with the previous version and targets adults diagnosed with, or suspected to have, IBS. A librarian created a literature search query, and a systematic review was conducted to identify candidate guidelines. Feasible documents were verified based on predetermined inclusion and exclusion criteria. The candidate seed guidelines were fully evaluated by the Guidelines Development Committee using the Appraisal of Guidelines for Research and Evaluation II quality assessment tool. After selecting 7 seed guidelines, the committee prepared evidence summaries to generate data exaction tables. These summaries comprised the 4 main themes of this version of the guidelines: colonoscopy; a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols; probiotics; and rifaximin. To adopt the core recommendations of the guidelines, the Delphi technique (ie, a panel of experts on IBS) was used. To enhance dissemination of the clinical practice guidelines, a Korean version will be made available, and a food calendar for patients with IBS is produced.

Experimental Models of Irritable Bowel Syndrome and the Role of the Enteric Neurotransmission

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal diseases in humans. It is characterized by visceral pain and/or discomfort, hypersensitivity and abnormal motor responses along with change in gut habits. Although the etio-pathogenesis of IBS is only partially understood, a main role has been attributed to psychosocial stress of different origin. Animal models such as neonatal maternal separation, water avoidance stress and wrap restraint stress have been developed as psychosocial stressors in the attempt to reproduce the IBS symptomatology and identify the cellular mechanisms responsible for the disease. The study of these models has led to the production of drugs potentially useful for IBS treatment. This review intends to give an overview on the results obtained with the animal models; to emphasize the role of the enteric nervous system in IBS appearance and evolution and as a possible target of drug therapies.

Irritable bowel syndrome in Asia: Pathogenesis, natural history, epidemiology, and management

Historically, the epidemiology of gastrointestinal diseases in Asia was different from that in Western countries. Early studies suggested a low prevalence of irritable bowel syndrome (IBS) in Asia. As the diagnosis of IBS is symptom-based and as symptom perception, expression, and interpretation are influenced by sociocultural perspectives including language, the presentation of IBS is expected to vary in different communities. Furthermore, the pathogenesis is multifactorial with psychosocial (stress, illness, behavior, and diet) and biological (infection, gut microbiota, and immune activation) variables interacting, and so, the present study can anticipate that the development of IBS will vary in different environments. In recognition of this aspect of functional gastrointestinal disorders, the recently published Rome IV documents have provided greater focus on cross-cultural factors. In this review, the present study seeks to highlight Asian perspectives by identifying historical trends and recent publications from the region and comparing these with the observations from Western societies.

Effect of herbal extract granules combined with otilonium bromide on irritable bowel syndrome with diarrhoea: a study protocol for a randomised controlled trial

INTRODUCTION

Irritable bowel syndrome (IBS), known as a functional and organic gastrointestinal disorder, is a collection of symptoms that occur together and generally include pain or discomfort in the abdomen and changes in bowel movement patterns. Due to the limitations of conventional treatments, alternative IBS treatments are used by many patients worldwide. Samryungbaekchulsan (SRS), a herbal formula, has long been used for alleviating diarrhoea-predominant IBS (D-IBS) in traditional Korean medicine. Otilonium bromide (OB) is an antimuscarinic compound used to relieve spasmodic pain in the gut, especially in IBS. Although herbal formulae and Western drugs are commonly coadministered for various diseases in Korea, few clinical studies have been conducted regarding the synergic effects of these treatments for any disease, including D-IBS.

METHODS AND ANALYSIS

This trial is a randomised, double-blinded, placebo-controlled, double-dummy, four-arm, parallel study. After a 2-week preparation period, 80 patients with D-IBS will be randomly assigned to one of four treatment groups consisting of SRS (water extract granules, 5 g/pack, three times a day) with OB (tablet form, one capsule three times a day) or their placebos, with treatment lasting for 8 weeks. Post-treatment follow-up will be conducted 4 weeks after the end of treatment. The primary outcome is the finding obtained using the Subject's Global Assessment of Relief method. The secondary outcomes are the severity of symptoms related to D-IBS, determined using a 10-point scale, and the change in symptoms.

ETHICS AND DISSEMINATION

This trial has full ethical approval of the Ethics Committee of Catholic Kwandong University International St. Mary's Hospital (IS15MISV0033) and the Korean Ministry of Food and Drug Safety (30769). The results of the study will be disseminated through a peer-reviewed journal and/or conference presentations.

TRIAL PROTOCOL VERSION

IS15MISV0033 version 4.0 (25 July 2016).

TRIAL REGISTRATION NUMBER

KCT0001621 (approval date: 10 August 2015).

Pharmacotherapy for Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a disorder of the brain-gut axis; the pathophysiological mechanisms include altered colonic motility, bile acid metabolism, neurohormonal regulation, immune dysfunction, alterations in the epithelial barrier and secretory properties of the gut. This article reviews the mechanisms, efficacy, and safety of current pharmacotherapy, and medications that are in phase III trials for the treatment of IBS. There remains a significant unmet need for effective treatments-particularly for the pain component of IBS-although the introduction of drugs directed at secretion, motility and a non-absorbable antibiotic provide options for the bowel dysfunction in IBS.

Dietary and pharmacological treatment of abdominal pain in IBS

This review introduces the principles of visceral sensation and appraises the current approaches to management of visceral pain in functional GI diseases, principally IBS. These approaches include dietary measures including fibre supplementation, low fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet, and pharmacological approaches such as antispasmodics, peppermint oil, antidepressants (tricyclic agents, selective serotonin reuptake inhibitors), 5-HT₃ receptor antagonists (alosetron, ondansetron, ramosetron), non-absorbed antibiotic (rifaximin), secretagogues (lubiprostone, linaclotide), μ-opioid receptor (OR) and κ-OR agonist, δ-OR antagonist (eluxadoline), histamine H1 receptor antagonist (ebastine), neurokinin-2 receptor antagonist (ibodutant) and GABAergic agents (gabapentin and pregabalin). Efficacy and safety are discussed based on pivotal trials or published systematic reviews and meta-analysis, expressing ORs or relative risks and their 95% CIs. Potential new approaches may be based on recent insights on mucosal expression of genes, and microRNA and epigenetic markers in human biopsies and in animal models of visceral hypersensitivity.The objectives of this review are to appraise the physiology and anatomy of gut sensation and the efficacy in the relief of visceral pain (typically in IBS) of several classes of therapies. These include fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) and different classes of medications (box 1). Box 1Classes of pharmacological agents for visceral painAntidepressants (tricyclic agents, selective serotonin reuptake inhibitors)Peppermint oil5-HT₃ receptor antagonists (alosetron, ondansetron, ramosetron)Non-absorbed antibiotic (rifaximin)Secretagogues (lubiprostone, linaclotide)μ-Opioid receptor (OR) and κ-OR agonist and δ-OR antagonist (eluxadoline)Histamine H1 receptor antagonist (ebastine)Neurokinin-2 receptor antagonist (ibodutant)GABAergic agents (gabapentin and pregabalin).

Clinical Practice Guideline: Irritable bowel syndrome with constipation and functional constipation in the adult

In this Clinical Practice Guideline we discuss the diagnostic and therapeutic approach of adult patients with constipation and abdominal complaints at the confluence of the irritable bowel syndrome spectrum and functional constipation. Both conditions are included among the functional bowel disorders, and have a significant personal, healthcare, and social impact, affecting the quality of life of the patients who suffer from them. The first one is the irritable bowel syndrome subtype, where constipation represents the predominant complaint, in association with recurrent abdominal pain, bloating, and abdominal distension. Constipation is characterized by difficulties with or low frequency of bowel movements, often accompanied by straining during defecation or a feeling of incomplete evacuation. Most cases have no underlying medical cause, and are therefore considered as a functional bowel disorder. There are many clinical and pathophysiological similarities between both disorders, and both respond similarly to commonly used drugs, their primary difference being the presence or absence of pain, albeit not in an "all or nothing" manner. Severity depends not only upon bowel symptom intensity but also upon other biopsychosocial factors (association of gastrointestinal and extraintestinal symptoms, grade of involvement, and perception and behavior variants). Functional bowel disorders are diagnosed using the Rome criteria. This Clinical Practice Guideline has been made consistent with the Rome IV criteria, which were published late in May 2016, and discuss alarm criteria, diagnostic tests, and referral criteria between Primary Care and gastroenterology settings. Furthermore, all the available treatment options (exercise, fluid ingestion, diet with soluble fiber-rich foods, fiber supplementation, other dietary components, osmotic or stimulating laxatives, probiotics, antibiotics, spasmolytics, peppermint essence, prucalopride, linaclotide, lubiprostone, biofeedback, antidepressants, psychological therapy, acupuncture, enemas, sacral root neurostimulation, surgery) are discussed, and practical recommendations are made regarding each of them.

Efficacy of otilonium bromide in irritable bowel syndrome: a pooled analysis

BACKGROUND

Otilonium bromide (OB) is a spasmolytic agent acting as an L-type calcium channel antagonist in intestinal and colonic smooth muscle cells (SMCs). We analyzed three independent clinical trials with homogeneous design on patients with irritable bowel syndrome (IBS). After 2 weeks receiving placebo, patients were randomized to receive OB (3 × 40 mg daily) or placebo for 15 weeks. We aimed to perform a pooled analysis of the data from these homogeneous clinical trials to evaluate the efficacy of OB treatment on symptoms and global response of patients.

METHODS

A total of 883 patients with IBS (69.8% women, mean age 46.2 years, 43.8% mixed type) were included, 442 treated with OB and 441 with placebo. The efficacy results from the three studies at weeks 5, 10 and 15 were pooled in an intention-to-treat (ITT) strategy, analyzed with a logistic regression model and described by forest plots.

RESULTS

Despite a placebo effect in all efficacy variables, a significant therapeutic effect of OB was observed at weeks 10 and 15 with reference to: (a) intensity and frequency of abdominal pain; (b) rate of responders as evaluated by patients (71.8% at week 10 and 77.2% at week 15); (c) severity of bloating; (d) rate of responders as evaluated by physicians (55% at week 10 and 63.9% at week 15). No significant OB effect was observed in stool frequency and consistency.

CONCLUSIONS

OB is more effective than placebo in IBS treatment. Therapeutic benefits are significant after 10 weeks and are maximal after 15 weeks of treatment.

[Irritable bowel syndrome with constipation and functional constipation in adults: Treatment (Part 2 of 2)]

In this Clinical practice guide we examine the diagnostic and therapeutic management of adult patients with constipation and abdominal discomfort, at the confluence of the spectrum of irritable bowel syndrome and functional constipation. Both fall within the framework of functional intestinal disorders and have major personal, health and social impact, altering the quality of life of the patients affected. The former is a subtype of irritable bowel syndrome in which constipation and altered bowel habit predominate, often along with recurring abdominal pain, bloating and abdominal distension. Constipation is characterised by infrequent or hard-to-pass bowel movements, often accompanied by straining during defecation or the sensation of incomplete evacuation. There is no underlying organic cause in the majority of cases; it being considered a functional bowel disorder. There are many clinical and pathophysiological similarities between the two conditions, the constipation responds in a similar way to commonly used drugs, the fundamental difference being the presence or absence of pain, but not in an "all or nothing" way. The severity of these disorders depends not only on the intensity of the intestinal symptoms but also on other biopsychosocial factors: association of gastrointestinal and extraintestinal symptoms, degree of involvement, forms of perception and behaviour. Functional bowel disorders are diagnosed using the Rome criteria. This Clinical practice guide adapts to the Rome IV criteria published at the end of May 2016. The first part (96, 97, 98) examined the conceptual and pathophysiological aspects, alarm criteria, diagnostic test and referral criteria between Primary Care and Gastroenterology. This second part reviews all the available treatment alternatives (exercise, fluid ingestion, diet with soluble fibre-rich foods, fibre supplements, other dietary components, osmotic or stimulating laxatives, probiotics, antibiotics, spasmolytics, peppermint essence, prucalopride, linaclotide, lubiprostone, biofeedback, antdepressants, psychological treatment, acupuncture, enemas, sacral root neurostimulation and surgery), and practical recommendations are made for each.

Irritable Bowel Syndrome: Pathophysiology and Current Therapeutic Approaches

Irritable bowel syndrome (IBS) is a prevalent condition affecting 10-20% of adults in most countries; IBS results in significant morbidity and health care costs. IBS is a disorder of the brain-gut axis, and recent insights into the pathophysiological mechanisms include altered bile acid metabolism, neurohormonal regulation, immune dysfunction, alterations in the epithelial barrier, and secretory properties of the gut. There remains a significant unmet need for effective treatments, particularly for the pain component of IBS, although the introduction of drugs directed at secretion, motility, and a nonabsorbable antibiotic provides an option for the bowel dysfunction in IBS.

Repeated otilonium bromide administration prevents neurotransmitter changes in colon of rats underwent to wrap restraint stress

Otilonium bromide (OB) is a spasmolytic drug successfully used for the treatment of irritable bowel syndrome (IBS). Its efficacy has been attributed to the block of L- and T-type Ca²⁺ channels and muscarinic and tachykinin receptors in the smooth muscle. Furthermore, in healthy rats, repeated OB administration modified neurotransmitter expression and function suggesting other mechanisms of action. On this basis, we investigated whether repeated OB treatment prevented the functional and neurochemical changes observed in the colon of rats underwent to wrap restrain stress (WRS) a psychosocial stressor considered suitable to reproduce the main IBS signs and symptoms. In control, WRS and OB/WRS rats functional parameters were measured in vivo and morphological investigations were done ex vivo in the colon. The results showed that OB counteracts most of the neurotransmitters changes caused by WRS. In particular, the drug prevents the decrease in SP-, NK1r-, nNOS-, VIP-, and S100β-immunoreactivity (IR) and the increase in CGRP-, and CRF1r-IR. On the contrary, OB does not affect the increase in CRF2r-IR neurons observed in WRS rats and does not interfere with the mild mucosal inflammation due to WRS. Finally, OB per se increases the Mr2 expression in the muscle wall and decreases the number of the myenteric ChAT-IR neurons. Functional findings show a significantly reduction in the number of spontaneous abdominal contraction in OB treated rats. The ability of OB to block L-type Ca²⁺ channels, also expressed by enteric neurons, might represent a possible mechanism through which OB exerts its actions.

A New, More Stable Polymorphic Form of Otilonium Bromide: Solubility, Crystal Structure, and Phase Transformation

A new polymorphic form of otilonium bromide is presented (Form I), and a thorough analysis of its crystal and molecular structure is performed. The compound suffers a temperature-driven first-order phase transition at about 396 K, which transforms it into the polymorph reported by Dapporto P and Sega A (Acta Cryst. 1986;C42:474-478) (Form II). Through thermal analysis and solubility experiments the relative stability of both crystal modifications were determined, confirming that at room temperature this new Form I is the more stable one, Form II existing just in a metastable state.

Novel pharmacological therapies for irritable bowel syndrome

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder, which represents a major cost to healthcare services. Current pharmacological treatment includes fibre supplements, antispasmodics, laxatives, loperamide and antidepressants. This article reviews the novel pharmacological treatments already or recently approved for patients with IBS-C (lubiprostone, linaclotide) and IBS-D (alosetron, ramosetron, rifaximin, eluxadoline). Furthermore, results for drugs in development (plecanatide, ibudutant and ebastine) or used in chronic constipation or for other indications, with potential application in IBS (prucalopride, elobixibat, mesalazine, ondansetron and colesevelam) are also reviewed.

Modern Management of Irritable Bowel Syndrome: More Than Motility

In the treatment of irritable bowel syndrome (IBS), loperamide seems efficacious for diarrhea and ispaghula for constipation, while musculotropic spasmolytics may relieve abdominal pain. Antidepressants were found to be efficacious for abdominal pain, but their tolerance may be problematic and the therapeutic effect varied largely between trials. While meta-analyses suggest efficacy of probiotics as a group, the quality of the trials is often suboptimal and there is large variability. Lubiprostone, a chloride channel activator, and linaclotide, a guanylyl cyclase-C agonist, showed favorable effects on multiple symptoms in IBS with constipation. For IBS with diarrhea (IBS-D), the 5-HT3 receptor antagonist ramosetron showed efficacy in men and women, but is currently only approved in Japan. A multicenter study with the anti-emetic 5-HT3 receptor antagonist ondansetron showed efficacy on stool pattern in IBS-D. The poorly absorbable antibiotic rifaximin and eluxadoline, a mu opioid receptor agonist and delta antagonist, both showed efficacy in phase III trials in IBS-D and were approved by the FDA. Eluxadoline was associated with increased occurrence of sphincter of Oddi spasm and biliary pancreatitis. The non-pharmacological treatment of IBS, with dietary interventions (mainly gluten elimination and low FODMAP (fructose, oligo-, di-, monosaccharides and polyols)) has received a lot of attention lately. While responder rates vary across studies, perhaps based on regional variations in dietary intake of FODMAPs, the dietary approach seems to have acquired recognition as a valid therapeutic alternative. Long-term studies and comparative studies with pharmacotherapy, as well as elucidation of the underlying mechanisms of action, are needed.

Pharmacological, Pharmacokinetic, and Pharmacogenomic Aspects of Functional Gastrointestinal Disorders

This article reviews medications commonly used for the treatment of patients with functional gastrointestinal disorders. Specifically, we review the animal models that have been validated for the study of drug effects on sensation and motility; the preclinical pharmacology, pharmacokinetics, and toxicology usually required for introduction of new drugs; the biomarkers that are validated for studies of sensation and motility endpoints with experimental medications in humans; the pharmacogenomics applied to these medications and their relevance to the FGIDs; and the pharmacology of agents that are applied or have potential for the treatment of FGIDs, including psychopharmacologic drugs.