Efficacy and safety of acotiamide for the treatment of functional dyspepsia: systematic review and meta-analysis

Prokinetics-safety and efficacy: The European Society of Neurogastroenterology and Motility/The American Neurogastroenterology and Motility Society expert review

BACKGROUND

Prokinetics are a class of pharmacological drugs designed to improve gastrointestinal (GI) motility, either regionally or across the whole gut. Each drug has its merits and drawbacks, and based on current evidence as high-quality studies are limited, we have no clear recommendation on one class or other. However, there remains a large unmet need for both regionally selective and/or globally acting prokinetic drugs that work primarily intraluminally and are safe and without systemic side effects.

PURPOSE

Here, we describe the strengths and weaknesses of six classes of prokinetic drugs, including their pharmacokinetic properties, efficacy, safety and tolerability and potential indications.

[Current status and prospects of using the prokinetic acotiamide in gastroenterology: A review]

Acotiamide is a prokinetic with a novel mechanism of action - an antagonist of muscarinic M1 and M2 receptors and an acetylcholinesterase inhibitor. Acetylcholine is the central mediator of the tone of the muscular components of the gastrointestinal tract, increasing its motor activity. Blockade of presynaptic M1 and M2 receptors neutralizes the inhibitory effect of the feedback mechanism on the acetylcholine synthesis, while inhibition of acetylcholinesterase in the synaptic cleft reduces the acetylcholine degradation. Currently, the clinical efficacy of acotiamide in the population of patients with functional dyspepsia is demonstrated in more than 10 clinical studies in different regions of the world, demonstrating a reduction of the symptoms of the disease during treatment with this agent and an improvement in the quality of life of patients. In addition, the combination of acotiamide with proton pump inhibitors optimizes the management of patients with gastroesophageal reflux disease.

PyRICo-Pilot: pyridostigmine to reduce the duration of postoperative ileus after colorectal surgery - a phase II study

AIM

Postoperative ileus (POI) is a major problem after colorectal surgery. Acetylcholinesterase inhibitors such as pyridostigmine increase gastrointestinal (GI) motility through a cholinergic anti-inflammatory pathway. The purpose of this phase II pilot study is to determine the safety of oral pyridostigmine after elective colorectal surgery.

METHOD

This is a Stage 2b safety study (IDEAL framework). All adult patients undergoing elective colorectal resection or formation or reversal of stoma at the Royal Adelaide Hospital between September 2020 and January 2021 were eligible. The primary outcomes were 30-day postoperative complications, reported adverse events and GI-2 - a validated composite outcome measure of recovery of GI function after surgery, defined as the interval from surgery until first passage of stool and tolerance of a solid intake for 24 h (in whole days) in the absence of vomiting.

RESULTS

Fifteen patients were included in the study. The median age was 58 (range 50-82) years and seven (47%) were men. Most participants had an American Society of Anesthesiologists grade ≥2 (53%) and the median body mass index was 27 (24-35) kg/m² . There were 13 postoperative complications [seven were Clavien-Dindo (CD) 1, five CD 2 and one CD 3]. None appeared directly related to pyridostigmine administration, and none of the patients had any overt symptoms of excessive parasympathetic activity. Median GI-2 was 2 (1-4) days.

CONCLUSION

Oral pyridostigmine appears to be safe to use after elective colorectal surgery in a select group of patients. However, considering this is a pilot study with a small sample size, larger controlled studies are needed to confirm this finding and establish efficacy for prevention of POI.

The Usefulness of Symptom-based Subtypes of Functional Dyspepsia for Predicting Underlying Pathophysiologic Mechanisms and Choosing Appropriate Therapeutic Agents

Functional dyspepsia (FD) is considered to be a heterogeneous disorder with different pathophysiological mechanisms or pathogenetic factors. In addition to traditional mechanisms, novel concepts regarding pathophysiologic mechanisms of FD have been proposed. Candidates of therapeutic agents based on novel concepts have also been suggested. FD is a symptom complex and currently diagnosed by symptom-based Rome criteria. In the Rome criteria, symptom-based subtypes of FD including postprandial distress syndrome and epigastric pain syndrome are recommended to be used, based on the assumption that each subtype is more homogenous in terms of underlying pathophysiologic mechanisms than FD as a whole. In this review, the usefulness of symptombased subtypes of FD for predicting underlying pathophysiologic mechanisms and choosing appropriate therapeutic agents was evaluated. Although several classic pathophysiologic mechanisms are suggested to be associated with individual dyspeptic symptoms, symptom-based subtypes of FD are not specific for a certain pathogenetic factor or pathophysiologic mechanism, and may be frequently associated with multiple pathophysiologic abnormalities. Novel concepts on the pathophysiology of FD show complex interactions between pathophysiologic mechanisms and pathogenetic factors, and prediction of underlying mechanisms of individual patients simply by the symptom pattern or symptom-based subtypes may not be accurate in a considerable proportion of cases. Therefore, subtyping by the Rome criteria appears to have limited value to guide therapeutic strategy, suggesting that the addition of objective parameters or subclassification reflecting physiologic or pathologic tests may be necessary for the targeted therapeutic approaches, particularly when therapeutic agents targeting novel mechanisms are available.

Clinical Practice Guidelines for Functional Dyspepsia in Korea

Functional dyspepsia (FD) is a chronic upper gastrointestinal (GI) symptom complex that routine diagnostic work-up, such as endoscopy, blood laboratory analysis, or radiological examination, fails to identify a cause. It is highly prevalent in the World population, and its response to the various available therapeutic strategies is only modest because of the heterogenous nature of its pathogenesis. Therefore, FD represents a heavy medical burden for healthcare systems. We constituted a guideline development committee to review the existing guidelines on the management of functional dyspepsia. This committee drafted statements and conducted a systematic review and meta-analysis of various studies, guidelines, and randomized control trials. External review was also conducted by selected experts. These clinical practice guidelines for FD were developed based on evidence recently accumulated with the revised version of FD guidelines released in 2011 by the Korean Society of Neurogastroenterology and Motility. These guidelines apply to adults with chronic symptoms of FD and include the diagnostic role of endoscopy, Helicobacter pylori screening, and systematic review and meta-analyses of the various treatment options for FD (proton pump inhibitors, H.pylori eradication, and tricyclic antidepressants), especially according to the FD subtype. The purpose of these new guidelines is to aid the understanding, diagnosis, and treatment of FD, and the targets of the guidelines are clinicians, healthcare workers at the forefront of patient care, patients, and medical students. The guidelines will continue to be revised and updated periodically.

The Diagnosis and Treatment of Functional Dyspepsia

BACKGROUND

Functional dyspepsia (FD) is one of the more common functional disorders, with a prevalence of 10-20%. It affectsthe gastrointestinal tract.

METHODS

This article is based on publications retrieved by a selective search of PubMed, with special attention to controlled trials, guidelines, and reviews.

RESULTS

Typical dyspeptic symptoms in functional dyspepsia include epigastric pain, sensations of pressure and fullness, nausea, and early subjective satiety. The etiology of the disorder is heterogeneous and multifactorial. Contributory causes include motility disturbances, visceral hypersensitivity, elevated mucosal permeability, and disturbances of the autonomic and enteric nervous system. There is as yet no causally directed treatment for functional dyspepsia. Its treatment should begin with intensive patient education regarding the benign nature of the disorder and with the establishment of a therapeutic pact for long-term care. Given the absence of a causally directed treatment, drugs to treat functional dyspepsia should be given for no more than 8-12 weeks. Proton-pump inhibitors, phytotherapeutic drugs, and Helicobacter pylori eradication are evidence-based interventions. For intractable cases, tricyclic antidepressants and psychotherapy are further effective treatment options.

CONCLUSION

The impaired quality of life of patients with functional dyspepsia implies the need for definitive establishment of the diagnosis, followed by symptom-oriented treatment for the duration of the symptomatic interval.

Management of Functional Somatic Syndromes and Bodily Distress

Functional somatic syndromes (FSS), like irritable bowel syndrome or fibromyalgia and other symptoms reflecting bodily distress, are common in practically all areas of medicine worldwide. Diagnostic and therapeutic approaches to these symptoms and syndromes vary substantially across and within medical specialties from biomedicine to psychiatry. Patients may become frustrated with the lack of effective treatment, doctors may experience these disorders as difficult to treat, and this type of health problem forms an important component of the global burden of disease. This review intends to develop a unifying perspective on the understanding and management of FSS and bodily distress. Firstly, we present the clinical problem and review current concepts for classification. Secondly, we propose an integrated etiological model which encompasses a wide range of biopsychosocial vulnerability and triggering factors and considers consecutive aggravating and maintaining factors. Thirdly, we systematically scrutinize the current evidence base in terms of an umbrella review of systematic reviews from 2007 to 2017 and give recommendations for treatment for all levels of care, concentrating on developments over the last 10 years. We conclude that activating, patient-involving, and centrally acting therapies appear to be more effective than passive ones that primarily act on peripheral physiology, and we recommend stepped care approaches that translate a truly biopsychosocial approach into actual management of the patient.

Gastroparesis: pharmacotherapy and cardiac risk

BACKGROUND

Gastroparesis is characterized by abnormal gastric motility and delayed emptying with symptoms of early satiety, postprandial fullness, bloating, nausea, vomiting and abdominal pain. Pharmacological discovery has been lagging because potential drugs often are associated with abnormalities of electrical conduction of the myocardium due to interaction with cardiac ion channels leading to limited pharmaceutical options for development of new drugs.

OBJECTIVE

Addresses the safety of drugs for gastroparesis in terms of cardiotoxicity related to the clinical use of prokinetics and antiemetics.

METHODS

Survey of QT drugs List and review of current literature.

RESULTS

Many prokinetic drugs are associated with cardiac adverse events and manifest as prolongation of ventricular repolarization, i.e., QT-interval prolongation of the electrocardiogram. This disturbance may develop into a potentially fatal polymorphic ventricular tachyarrhythmia; Torsade de Pointes. Co-administration of prokinetics with other drugs affecting the repolarization process, pharmacokinetic interactions leading to increased blood levels, or the presence of clinical risk factors could further increase the risk for cardiac arrhythmias.

CONCLUSIONS

It is important that clinicians managing gastroparesis are aware of the arrhythmogenic potential of drugs used clinically and risk factors that contribute to QT prolongation to safeguard patients at risk for drug-induced cardiac arrhythmia.

Application of Pyridostigmine in Pediatric Gastrointestinal Motility Disorders: A Case Series

BACKGROUND

Gastrointestinal (GI) motility disorders are common in children. Treatment is challenging with limited medical and surgical options. Pyridostigmine, an acetyl cholinesterase inhibitor, increases acetylcholine at the neuromuscular junction promoting intestinal contractions. Little is known about the role and dosing of pyridostigmine in pediatric GI motility disorders.

METHODS

We present a case series of children with GI dysmotility managed with oral pyridostigmine. Patients' diagnoses include chronic intestinal pseudo-obstruction, gastroparesis with delayed small bowel transit, chronic constipation with failure to thrive, and prolonged ileus after pelvic surgery with chronic opioid use.

RESULTS

Pyridostigmine was effective and safe in all cases. Pyridostigmine decreased abdominal distention, increased bowel movement frequency, and improved enteral feeding tolerance. Effective dosing ranged between 0.25-2.0 mg/kg/day. One patient experienced cramping abdominal pain while on pyridostigmine, but pain resolved after medication was discontinued.

CONCLUSION

We found oral pyridostigmine to be helpful in children with different GI motility problems. Pyridostigmine should be considered in such patients when other treatment interventions have not been beneficial.

Functional Dyspepsia: Advances in Diagnosis and Therapy

Functional dyspepsia (FD) is a common but under-recognized syndrome comprising bothersome recurrent postprandial fullness, early satiety, or epigastric pain/burning. Epidemiologically, there are two clinically distinct FD syndromes (although these often overlap clinically): postprandial distress syndrome (PDS; comprising early satiety or meal-related fullness) and epigastric pain syndrome. Symptoms of gastroesophageal reflux disease overlap with FD more than expected by chance; a subset has pathological acid reflux. The pre-test probability of FD in a patient who presents with classical FD symptoms and no alarm features is high, approximately 0.7. Coexistent heartburn should not lead to the exclusion of FD as a diagnosis. One of the most exciting observations in FD has been the consistent finding of increased duodenal eosinophilia, notably in PDS. Small bowel homing T cells, signaling intestinal inflammation, and increased cytokines have been detected in the circulation, and elevated tumor necrosis factor-α levels have been significantly correlated with increased anxiety. Postinfectious gastroenteritis is a risk factor for FD. Therapeutic options remain limited and provide only symptomatic benefit in most cases. Only one therapy is known to change the natural history of FD–Helicobacter pylori eradication. Treatment of duodenal eosinophilia is under investigation.

Prokinetics in the Management of Functional Gastrointestinal Disorders

PURPOSE OF REVIEW

The goal of this review is to review the current status of prokinetics and to place it in historical context. Impaired motility and thus propulsion have long been thought to play important roles in the pathogenesis of a number of gastrointestinal disorders including gastroesophageal reflux disease (GERD), gastroparesis, chronic idiopathic pseudo-obstruction, and constipation. Historically, disordered motility was also thought to contribute to a number of functional gastrointestinal disorders such as functional dyspepsia (FD) and irritable bowel syndrome (IBS).

RECENT FINDINGS

As we learn more of the pathophysiology of FD, IBS, GERD, constipation, and gastroparesis, the limitations of a therapeutic strategy based on the stimulation of motility (i.e., the use of a prokinetic) have become apparent and the disappointments of the past explained. The development of prokinetic drugs has also been hampered by the non-selective nature of many of the agents studied to date which resulted in some unexpected side effects. There is still an unmet need for an effective and safe prokinetic, but drug development in this area must be mindful of the challenges of the area and the need for selectivity for a given target receptor.

Prokinetics for the treatment of functional dyspepsia: Bayesian network meta-analysis

BACKGROUND

Controversies persist regarding the effect of prokinetics for the treatment of functional dyspepsia (FD). This study aimed to assess the comparative efficacy of prokinetic agents for the treatment of FD.

METHODS

Randomized controlled trials (RCTs) of prokinetics for the treatment of FD were identified from core databases. Symptom response rates were extracted and analyzed using odds ratios (ORs). A Bayesian network meta-analysis was performed using the Markov chain Monte Carlo method in WinBUGS and NetMetaXL.

RESULTS

In total, 25 RCTs, which included 4473 patients with FD who were treated with 6 different prokinetics or placebo, were identified and analyzed. Metoclopramide showed the best surface under the cumulative ranking curve (SUCRA) probability (92.5%), followed by trimebutine (74.5%) and mosapride (63.3%). However, the therapeutic efficacy of metoclopramide was not significantly different from that of trimebutine (OR:1.32, 95% credible interval: 0.27-6.06), mosapride (OR: 1.99, 95% credible interval: 0.87-4.72), or domperidone (OR: 2.04, 95% credible interval: 0.92-4.60). Metoclopramide showed better efficacy than itopride (OR: 2.79, 95% credible interval: 1.29-6.21) and acotiamide (OR: 3.07, 95% credible interval: 1.43-6.75). Domperidone (SUCRA probability 62.9%) showed better efficacy than itopride (OR: 1.37, 95% credible interval: 1.07-1.77) and acotiamide (OR: 1.51, 95% credible interval: 1.04-2.18).

CONCLUSIONS

Metoclopramide, trimebutine, mosapride, and domperidone showed better efficacy for the treatment of FD than itopride or acotiamide. Considering the adverse events related to metoclopramide or domperidone, the short-term use of these agents or the alternative use of trimebutine or mosapride could be recommended for the symptomatic relief of FD.

Acotiamide improves stress-induced impaired gastric accommodation

BACKGROUND

Gastric accommodation is a reflex reaction related to gastric reservoir function. Psychological stress, such as anxiety, inhibits gastric accommodation in humans. Acotiamide enhances the effect of acetylcholine in the enteric nervous system, enhances gastric contractility, and accelerates delayed gastric emptying. However, the effect of acotiamide on stress-induced impaired gastric accommodation remains unclear. Therefore, we examined the effect of acotiamide on gastric accommodation and stress-induced impaired gastric accommodation using a conscious guinea pig model.

METHODS

A polyethylene bag was inserted through the distal region of the gastric body into the proximal stomach of 5-week-old male Hartley guinea pigs. Gastric accommodation was evaluated by measuring the intrabag pressure in the proximal stomach after oral administration of a liquid meal. In the stress model, animals were subjected to water-avoidance stress. Acotiamide (Z-338) or nizatidine was administered subcutaneously. Fecal output was determined as the number of fecal pellets.

KEY RESULTS

Administration of the liquid meal significantly decreased intrabag pressure, indicating induction of gastric accommodation. Acotiamide treatment prolonged liquid meal-induced gastric accommodation and significantly increased the number of fecal pellets compared to controls. Water-avoidance stress significantly inhibited liquid meal-induced gastric accommodation. Pretreatment with acotiamide significantly improved stress-induced impaired gastric accommodation. The number of fecal pellets in the acotiamide group increased significantly compared to controls. Acotiamide, but not nizatidine, significantly decreased gastric emptying.

CONCLUSIONS & INFERENCES

Acotiamide prolongs gastric accommodation and improves stress-induced impaired gastric accommodation, indicating a potential role for acotiamide in the treatment of functional dyspepsia through its effects on gastric accommodation reactions.

The Role of Duodenal Inflammation in Functional Dyspepsia

Functional dyspepsia (FD) is common and significantly impairs quality of life. Symptoms of FD are considered to originate from the gastroduodenal region, classified by the Rome criteria as disorders of brain-gut interaction without structural alteration. However, it is now apparent that FD is a number of syndromes, the epigastric pain syndrome (bothersome epigastric pain or epigastric burning) and the postprandial distress syndrome (with bothersome postprandial fullness or early satiation) and there are wide-ranging symptoms and severity. The origin of these troublesome symptoms is now considered to be a result of disrupted gastroduodenal neuropathophysiology. The complexity of the syndrome indicates that there must be different triggers, supported by the limited efficacy of the many treatments available. Current research based on evidence by association suggests that duodenal contents, including the duodenal microbiome, pathogens, and allergy may be triggers of FD. Recent studies have also shown that systemic responses of increased circulating lymphocytes and elevated proinflammatory cytokines and subtle inflammation in the duodenum may accompany the onset and persistence of symptoms. This inflammatory phenotype is characterized by innate inflammation, an eosinophil infiltrate in the duodenum in FD in those with postprandial distress syndrome. Routine histopathology practice does not quantify these cells so the status of FD is not yet appreciated as an inflammatory condition. Thus functional is becoming inflammatory and this breakthrough in understanding that functional does not necessarily mean no, but subtle pathology, may improve therapeutic options, which are currently aimed at symptom relief rather than targeted at underlying pathology.

Effects of Electroacupuncture on Interstitial Cells of Cajal (ICC) Ultrastructure and Connexin 43 Protein Expression in the Gastrointestinal Tract of Functional Dyspepsia (FD) Rats

Background

Gastrointestinal motility disorder is the main clinical manifestation in functional dyspepsia (FD) patients. Electroacupuncture is effective in improving gastrointestinal motility disorder in FD; however, the underlying mechanism remains unclear. It has been demonstrated that interstitial cells of Cajal (ICC) are pacemaker cells in the gastrointestinal tract, and the pacemaker potential is transmitted to nearby cells through gap junctions between ICC or ICC and the smooth muscle. Therefore, this study aimed to assess the effects of electroacupuncture on ICC ultrastructure and expression of the gap junction protein connexin 43 (Cx43) in FD rats.

Material/Methods

The animals were randomized into 3 groups: control, model, and electroacupuncture. Electroacupuncture was applied at Zusanli (ST36) in the electroacupuncture group daily for 10 days, while no electroacupuncture was applied to model group animals.

Results

Ultrastructure of ICC recovered normally in gastric antrum and small intestine specimens was improved, with Cx43 expression levels in these tissues significantly increased in the electroacupuncture group compared with the model group.

Conclusions

These findings indicated that electroacupuncture is effective in alleviating ICC damage and reduces Cx43 levels in FD rats, and suggest that ICC and Cx43 are involved in electroacupuncture treatment in rats with FD to improve gastrointestinal motility disorders.

Emerging treatments in neurogastroenterology: Acotiamade, a novel treatment option for functional dyspepsia

BACKGROUND

Acotiamide hydrochloride (Z-338) is a new therapeutic agent for functional dyspepsia (FD). In 2013, the use of acotiamide was approved by the Japanese health insurance system.

PURPOSE

The aim of this review is to summarize the present staus of basic and clinical approach to acotiamide for the treatment of functional dyspepsia. The agent inhibits acetylcholinesterase in vitro and enhances muscle motility ex vivo. In phase-II studies, 100 mg three times daily (t.i.d.) was determined to be the optimal dose for the treatment of FD. In phase-III studies, overall treatment efficacy (OTE) was significantly better in the acotiamide group (52.2%) than in the placebo group (34.8%). However, the mechanism of its efficacy needs to be further elucidated. Acotiamide effectively improved FD symptoms, particularly postprandial distress syndrome symptoms, without causing major adverse effects.

Profile of acotiamide in the treatment of functional dyspepsia

Efficacy of acotiamide for improving symptoms in patients with functional dyspepsia was shown by several clinical trials. In a randomized, double-blind, placebo-controlled, parallel-group comparative Phase III trial conducted in Japan, 100 mg of acotiamide three times a day for 4 weeks was more effective than a placebo for improving symptoms, and quality of life. Acotiamide was well-tolerated treatment, with no significant adverse events. The aim of this review was to summarize the current evidence of the efficacy of acotiamide in the treatment of patients with functional dyspepsia.

Women and functional dyspepsia

Functional dyspepsia is relatively common yet poorly understood. The best accepted diagnostic criteria are the Rome III criteria. The epidemiology, healthcare seeking rates, impact and pathophysiology are reviewed with a focus on women. Treatment is limited with no clearly established regimen currently recommended. Duodenal eosinophilia may be found in a subset. Proton pump inhibitors and prokinetic agents represent the standard therapeutic regimen after Helicobacter pylori infection has been eliminated. Some novel agents such as the prokinetic acotiamide appear promising; however, the need for a safe and efficacious treatment remains largely unmet. This review also describes the currently available management options for functional dyspepsia.

Therapeutic strategies for functional dyspepsia and irritable bowel syndrome based on pathophysiology

Functional gastrointestinal disorders (FGIDs) are common and distressing. They are so named because a defined pathophysiology in terms of structural or biochemical pathways is lacking. Traditionally FGIDs have been conceptualized as brain-gut disorders, with subgroups of patients demonstrating visceral hypersensitivity and motility abnormalities as well as psychological distress. However, it is becoming apparent that there are certain structural or biochemical gut alterations among subsets with the common FGIDs, most notably functional dyspepsia (FD) and irritable bowel syndrome (IBS). For example, a sodium channel mutation has been identified in IBS that may account for 2 % of cases, and subtle intestinal inflammation has been observed in both IBS and FD. Other research has implicated early life events and stress, autoimmune disorders and atopy and infections, the gut microbiome and disordered mucosal immune activation in patients with IBS or FD. Understanding the origin of symptoms in FGIDs will allow therapy to be targeted at the pathophysiological changes, not at merely alleviating symptoms, and holds hope for eventual cure in some cases. For example, there are promising developments in manipulating the microbiome through diet, prebiotics and antibiotics in IBS, and testing and treating patients for Helicobacter pylori infection remains a mainstay of therapy in patients with dyspepsia and this infection. Locally acting drugs such as linaclotide have been an advance in treating the symptoms of constipation-predominant IBS, but do not alter the natural history of the disease. A role for a holistic approach to patients with FGIDs is warranted, as brain-to-gut and gut-to-brain pathways appear to be activated.