Tegaserod inhibits noxious rectal distention induced responses and limbic system c-Fos expression in rats with visceral hypersensitivity

Evaluation and management of irritable bowel syndrome

ABSTRACT

Irritable bowel syndrome (IBS) is a common diagnosis that providers encounter in primary and specialty care. IBS is characterized by chronic abdominal pain and altered bowel habits. The American College of Gastroenterology recently released an updated guideline for the evaluation and management of patients with IBS. According to the guideline, it remains important to confirm diagnosis based on criteria and lack of alarm signs; IBS should not be a diagnosis of exclusion. Management should be focused on addressing altered bowel habits and global symptoms using a multidisciplinary approach.

Tegaserod: What's Old Is New Again

Irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) are common gastrointestinal disorders imposing considerable impact on the quality of life and well-being of affected individuals. A paucity of evidence-based treatment options exist for CIC and IBS-C sufferers. Tegaserod, a 5-HT₄ agonist, has a substantial body of preclinical and clinical study evidence to support its beneficial role in modulating sensorimotor function of the luminal gastrointestinal tract. Tegaserod was first approved for use by the U.S. Food and Drug Administration for the management of IBS-C and CIC in 2002 and 2004, respectively. Tegaserod enjoyed a successful uptake in the management of these disorders during its first several years of availability in the United States, but was later withdrawn from the market in 2007 over concerns related to adverse cardiovascular events. Since then, additional safety data has been generated, and following a resubmission and review by the Food and Drug Administration, in April 2019, tegaserod was once again approved for use in IBS-C under a more restricted labeling, confining use to women under 65 years of age without heart disease or additional cardiovascular risk factors. This review summarizes the regulatory journey of tegaserod and details the existing pharmacokinetic, physiologic, clinical, and safety data of tegaserod generated over the last 2 decades. The discussion also examines the future of tegaserod in the treatment of these constipation disorders, as well as its potential role in other related disorders of brain-gut interaction.

Diarrhea-Predominant and Constipation-Predominant Irritable Bowel Syndrome: Current Prescription Drug Treatment Options

Irritable bowel syndrome (IBS) is a heterogenous disease with a variety of therapeutic options, including eight prescription drugs approved for use in IBS in the USA. Choosing among the myriad treatment options requires attention to patient preferences both on clinical outcomes and costs associated with treatment. We performed a narrative review of the literature to summarize these important determinants of treatment choice including: labeled indications; clinical profiles of efficacy, safety, and tolerability of prescription drugs; and cost-effectiveness for diarrhea-predominant IBS drugs (IBS-D: alosetron, eluxadoline, and rifaximin) and constipation-predominant IBS drugs (IBS-C: linaclotide, lubiprostone, plecanatide, tegaserod, and tenapanor). We then review the standard model of shared decision-making aimed at guiding an informed, patient-centered discussion to integrate comparative clinical and cost outcomes toward choosing an IBS treatment in practice.

ACG Clinical Guideline: Management of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a highly prevalent, chronic disorder that significantly reduces patients' quality of life. Advances in diagnostic testing and in therapeutic options for patients with IBS led to the development of this first-ever American College of Gastroenterology clinical guideline for the management of IBS using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Twenty-five clinically important questions were assessed after a comprehensive literature search; 9 questions focused on diagnostic testing; 16 questions focused on therapeutic options. Consensus was obtained using a modified Delphi approach, and based on GRADE methodology, we endorse the following: We suggest that a positive diagnostic strategy as compared to a diagnostic strategy of exclusion be used to improve time to initiating appropriate therapy. We suggest that serologic testing be performed to rule out celiac disease in patients with IBS and diarrhea symptoms. We suggest that fecal calprotectin be checked in patients with suspected IBS and diarrhea symptoms to rule out inflammatory bowel disease. We recommend a limited trial of a low fermentable oligosaccharides, disacchardies, monosaccharides, polyols (FODMAP) diet in patients with IBS to improve global symptoms. We recommend the use of chloride channel activators and guanylate cyclase activators to treat global IBS with constipation symptoms. We recommend the use of rifaximin to treat global IBS with diarrhea symptoms. We suggest that gut-directed psychotherapy be used to treat global IBS symptoms. Additional statements and information regarding diagnostic strategies, specific drugs, doses, and duration of therapy can be found in the guideline.

Peripherally acting therapies for the treatment of irritable bowel syndrome

Gut-acting therapies are common therapies for irritable bowel syndrome (IBS). Most of these peripheral acting agents are primarily targeted at individual symptoms. The evidence supporting the use of these agents in IBS is largely anecdotal. Serotonergic agents and the chloride channel activator lubiprostone have shown efficacy in treating symptoms of IBS. The clinical evidence supporting the use of these agents is based on data from high-quality clinical trials. The use of serotonergic agents for IBS in the United States is limited to the 5-hydroxytryptamine-3 antagonist alosetron in the treatment of women with severe IBS with diarrhea refractory to traditional therapy.

The role of experimental models in developing new treatments for irritable bowel syndrome

Irritable bowel syndrome (IBS) is characterized by chronic, recurrent abdominal pain and altered bowel habits and is currently defined by symptom criteria and the absence of detectable organic disease. The underlying pathophysiology remains incompletely understood. Despite considerable efforts by the scientific community and the pharmaceutical industry to develop novel pharmacological treatments aimed at chronic visceral pain, the traditional approach to identifying and evaluating novel drugs for this target have largely failed to translate into effective IBS treatments. However, several novel drugs aimed at normalizing bowel movements have produced clinical effects, not only on the primary target, but also on pain and discomfort. While some of the commonly used experimental animal models for the pain dimension of IBS have some face and construct validity, the predictive validity of most of the models is either unknown, or has been disappointing. A reverse translational approach is proposed, which is based on identification and characterization of brain endophenotypes in patients, followed by translation of these endophenotypes for pharmacological studies in rodent models.

Functional GI disorders: from animal models to drug development

Despite considerable efforts by academic researchers and by the pharmaceutical industry, the development of novel pharmacological treatments for irritable bowel syndrome (IBS) and other functional gastrointestinal (GI) disorders has been slow and disappointing. The traditional approach to identifying and evaluating novel drugs for these symptom-based syndromes has relied on a fairly standard algorithm using animal models, experimental medicine models and clinical trials. In the current article, the empirical basis for this process is reviewed, focusing on the utility of the assessment of visceral hypersensitivity and GI transit, in both animals and humans, as well as the predictive validity of preclinical and clinical models of IBS for identifying successful treatments for IBS symptoms and IBS-related quality of life impairment. A review of published evidence suggests that abdominal pain, defecation-related symptoms (urgency, straining) and psychological factors all contribute to overall symptom severity and to health-related quality of life. Correlations between readouts obtained in preclinical and clinical models and respective symptoms are small, and the ability to predict drug effectiveness for specific as well as for global IBS symptoms is limited. One possible drug development algorithm is proposed which focuses on pharmacological imaging approaches in both preclinical and clinical models, with decreased emphasis on evaluating compounds in symptom-related animal models, and more rapid screening of promising candidate compounds in man.

Safety, tolerability and satisfaction with tegaserod therapy in Asia-Pacific patients with irritable bowel syndrome with constipation

BACKGROUND AND AIM

The 5-HT(4) receptor agonist tegaserod (6 mg b.i.d.) provides significantly better overall multiple symptom relief compared with placebo in patients with irritable bowel syndrome with constipation (IBS-C). The clinical benefit and safety of tegaserod in IBS-C patients has been demonstrated worldwide in several studies. The aim of this study was to obtain further safety and tolerability data in patients with IBS in the Asia-Pacific region, and to assess patients' satisfaction and compliance with treatment and willingness to re-use tegaserod in a post-marketing setting.

METHODS

A multicenter, single-arm, open-label trial was conducted at 869 outpatient centers in 10 countries. Men and women with IBS, whose predominant bowel symptom was not diarrhea (non-D-IBS), received tegaserod for 4-12 weeks. Safety and tolerability were assessed by recording adverse events (AE). Patients were questioned about compliance, satisfaction with treatment and willingness to use tegaserod in future.

RESULTS

Data were available from 14 537 patients (18% men, 82% women). Four percent of patients reported at least one AE. The most common AE were diarrhea (2%) and abdominal pain (1%), and most treatment-related AE occurred in the first week of treatment. Serious AE (SAE) were observed in eight patients, and no deaths were reported. Most patients (79%) reported to be satisfied or very satisfied with treatment, and 76% stated they would use tegaserod in the future. Compliance was 97%.

CONCLUSIONS

Tegaserod has a favorable safety and tolerability profile for treating non-D-IBS and IBS-C in men and women in the Asia-Pacific region. Satisfaction with tegaserod treatment can be expected in the majority of patients.

Serotonergic and non-serotonergic targets in the pharmacotherapy of visceral hypersensitivity

Visceral hypersensitivity is considered a key mechanism in the pathogenesis of functional gastrointestinal (GI) disorders. Targeting visceral hypersensitivity seems an attractive approach to the development of drugs for functional GI disorders. This review summarizes current knowledge on targets for the treatment of visceral hypersensitivity, and the status of current and future drug and probiotic treatment development, and the role of pharmacogenomic factors.

The rationale, efficacy and safety evidence for tegaserod in the treatment of irritable bowel syndrome

A growing body of evidence implicates abnormal serotonergic regulation of gastrointestinal function in the pathogenesis of the irritable bowel syndrome (IBS). Drugs targeting this system are therefore attractive concepts. The partial 5-HT4 receptor agonist tegaserod might be predicted to have positive therapeutic effects on a constipated and uncomfortable gut. However, IBS runs a chronic, benign course and carries no associated mortality, so it is imperative that the safety profile of new pharmacological agents made available to physicians is exemplary. The authors review the evidence for 5-HT in the aetiology of IBS and its symptoms, and the data available concerning the partial 5-HT4 receptor agonist tegaserod, in terms of rationale, efficacy and safety.

Tegaserod in the treatment of irritable bowel syndrome with constipation

Tegaserod, a novel serotonin receptor agonist, has gained acceptance and widespread use for the treatment of women with irritable bowel syndrome and constipation. Development of this therapy evolved from the emerging role of serotonin in gastrointestinal motor, secretory and sensory functions. The efficacy and safety of tegaserod has been well established in women suffering from irritable bowel syndrome with constipation. Large, randomized, double-blind, placebo-controlled trials involving more than 3500 predominantly female patients with irritable bowel syndrome and constipation have demonstrated the superiority of tegaserod over placebo in improving global and individual symptoms. The most common side effects of tegaserod in clinical trials were diarrhea and headache. Recent data suggest that retreatment with tegaserod after a drug holiday is efficacious, opening the door to the possibility of intermittent therapy for patients with irritable bowel syndrome and constipation. Areas in need of further investigation include the role of tegaserod in the treatment of pain and bloating in irritable bowel syndrome, whether tegaserod has a role in male patients, the long-term efficacy of tegaserod, whether tolerance develops in a subset of patients with extended therapy and whether tegaserod is beneficial for the treatment of other functional gastrointestinal disorders.

Review article: The role of serotonergic agents in the treatment of patients with primary chronic constipation

Chronic constipation is a highly prevalent disorder that is associated with significant direct and indirect costs and has substantial impact on patient quality of life. It is more common among women and non-white populations and is evenly distributed across adult age groups. Constipation is a heterogeneous disorder associated with multiple symptoms and aetiologies. Recent research has increased our understanding of the pathogenesis of this disorder and the central role of the neurotransmitter serotonin in mediating gastrointestinal motility, secretion and sensation. Abnormal serotonin signalling and reuptake appear to play central roles in the symptoms of a subset of patients with chronic constipation. This observation provides a rationale for the use of targeted serotonergic agents for the treatment of chronic constipation. As the role of serotonin in gastrointestinal function is further elucidated and additional candidate drugs are developed, it is likely that serotonergic agents will afford additional treatment options for patients with chronic constipation. This article provides a concise review of the evidence supporting a role for serotonin in the pathogenesis of chronic constipation and a summary of the currently available evidence supporting the use of serotonergic agents for this disorder.