Physiological and pathological roles of the accommodation response in lower esophageal sphincter relaxation during wet swallows

Evaluating the efficacy and safety of acotiamide in patients with esophagogastric junction outflow obstruction: study protocol for an investigator-initiated, multi-center, randomized, double-blind, placebo-controlled phase II trial

BACKGROUND

We have determined that the impaired accommodation of the lower esophageal sphincter (LES) underlies the pathogenesis of esophagogastric junction outflow obstruction (EGJOO). We have also found that acotiamide may treat EGJOO by improving impaired LES accommodation. The effects of acotiamide in patients with EGJOO need to be further confirmed in a prospective study.

METHODS

This trial is a multicenter, randomized, double-blind, placebo-controlled study to compare the efficacy and safety of acotiamide (300 mg/day or 600 mg/day) with those of a placebo in the treatment of patients with EGJOO. The primary endpoint will be the proportion of patients who report an improvement in symptom of food sticking in the chest after 4 weeks of treatment period 1. The secondary endpoints will be the proportion of patients with normalized integrated relaxation pressure (IRP), the value of change from baseline in the distal contractile integral, basal LES pressure, EGJOO-quality of life score, Gastrointestinal Symptom Rating Scale, and the correlation between IRP and each symptom score. During the 2-year trial period, 42 patients from five institutions will be enrolled.

DISCUSSION

This trial will provide evidence to clarify the efficacy and safety of acotiamide as a treatment for patients with EGJOO. Acotiamide might help improve the quality of life of patients with EGJOO and is expected to prevent the progression of EGJOO to achalasia.

TRIAL REGISTRATION

This study was approved by the Institutional Review Board (IRB) of Kyushu University Hospital as well as the local IRBs of the participating sites for clinical trials and registered in the Japan Registry of Clinical Trials (jRCT: 2071210072). The registration date is on October 11, 2021.

The treatment effects of acotiamide in esophagogastric outflow obstruction: a prospective longitudinal observational study

OBJECTIVES

We have found that an altered lower esophageal sphincter (LES) accommodation response is an underlying cause of esophagogastric junction outflow obstruction (EGJOO). The objective of this study was to examine the treatment effect of acotiamide, a prokinetic agent which improves impaired gastric accommodation in functional dyspepsia, in patients with EGJOO.

METHODS

A prospective observational longitudinal study was conducted between October 2014 and March 2020. Acotiamide (100 mg, 3 times a day) was administered to 25 patients with EGJOO for 4 weeks. High-resolution manometry (HRM) was performed just before and after 4 weeks of treatment.

RESULTS

As the primary outcome, the extent of integrated relaxation pressure (IRP) after treatment (14.6, 12.1-22.0 mmHg) was significantly lower than that before treatment (19.4, 17.1-27.4 mmHg). The extent of LES accommodation index after treatment (32.7, 21.0-40.0 mmHg) was also significantly lower than that before treatment (39.3, 31.2-50.2 mmHg). Acotiamide normalized the IRP (< 15 mmHg) in 13 of 25 patients with EGJOO (52%), and the IRP was decreased in 20 of 25 patients with EGJOO (80%). As the secondary outcome, the total FSSG score in 25 patients with EGJOO before and after acotiamide treatment showed no significant difference. In a sub-analysis of 13 patients in whom EGJOO was normalized by acotiamide, however, dysphagia was reported to be significantly improved by acotiamide.

CONCLUSIONS

Acotiamide has a treatment effect on patients with EGJOO via a reduction in the IRP level through the lowering of both the basal LES pressure and LES accommodation response. Dysphagia is a key symptom to be evaluated and treated in patients with EGJOO.