iWAIST Trial: ERCG (Endoscopic Radial Compression Gastroplasty) vs Optimized Lifestyle Intervention for Weight Loss

Liu Yan216 enrolled

Overview

Obesity and overweight are rising in Chinese populations, where metabolic risks begin at lower BMI thresholds than in Western cohorts. Many individuals with overweight or mild-to-moderate obesity are ineligible or unwilling to undergo bariatric surgery due to invasiveness and risk. Endoscopic bariatric and metabolic therapies offer minimally invasive alternatives but vary in complexity, cost, and safety profiles. Investigators developed a sutureless endoscopic procedure, Endoscopic Radial Compression Gastroplasty (ERCG), which reduces gastric volume by apposing gastric walls using a clip-and-loop system. This randomized controlled trial evaluates the efficacy and safety of ERCG versus an optimized lifestyle intervention in Asian adults with BMI 24.0-37.4 kg/m² who have not succeeded with conservative measures. Preliminary studies suggest ERCG can achieve approximately 12% total body weight loss (TBWL) at 3 months. The primary endpoint is percent TBWL at 3 months; secondary outcomes include changes in BMI, metabolic parameters, quality of life, and adverse events. Results are expected to inform the role of ERCG as a safe, effective, and scalable option between conservative care and bariatric surgery.

The prevalence of obesity and overweight continues to increase worldwide, and Chinese populations are particularly vulnerable due to lower thresholds for metabolic risk compared with Western populations. Individuals with overweight or mild-to-moderate obesity (BMI 24.0-37.4 kg/m²) often fail conservative measures but are ineligible or unwilling to undergo bariatric surgery because of its invasiveness, risk, and costs. This creates an unmet need for minimally invasive, effective, and scalable interventions. Endoscopic bariatric and metabolic therapies (EBMTs) have emerged as alternatives, but many existing procedures involve technically complex endoscopic suturing, high costs, or device-related risks. Investigators developed ERCG, a novel endoscopic procedure that reduces gastric volume by apposing the gastric walls using a newly designed clip-and-loop system. Preliminary studies demonstrated that ERCG can induce rapid weight loss, with mean percent total body weight loss (TBWL) of approximately 12% at 3 months, while maintaining a favorable safety profile. This randomized controlled trial aims to evaluate the efficacy and safety of ERCG compared with an optimized lifestyle intervention (OLI) in Chinese adults with overweight and mild-to-moderate obesity who have failed conservative weight reduction efforts. Eligible participants will be randomized 1:1 into two groups. The experimental group will undergo ERCG under general anesthesia or deep sedation, following a standardized perioperative protocol, then receive structured OLI. The control group will receive structured OLI consisting of individualized dietary counseling, caloric restriction, exercise prescription, and behavioral support. Follow-up visits are scheduled at 1 month, 2 month, 3 month and 6 month after enrollment. The primary endpoint is percent TBWL at 3 months, assessed using standardized weight measurement protocols. Secondary endpoints include %EBWL at 3 and 6 months, changes in BMI, metabolic parameters (fasting plasma glucose, HbA1c, insulin resistance indices, lipid profile), quality of life assessed by validated questionnaires (IWQOL-Lite), and the incidence of adverse events classified according to international standards. Randomization will be computer-generated with concealed allocation, and outcome assessors will be blinded to treatment assignment. Analyses will follow the intention-to-treat principle with appropriate methods for handling missing data. The study is expected to generate high-quality evidence regarding the short-term and medium-term efficacy of ERCG, to clarify its safety profile, and to determine whether ERCG can serve as a safe and scalable option bridging the therapeutic gap between conservative lifestyle approaches and bariatric surgery for overweight and mildly to moderately obese Chinese populations.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 65 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Asian adults aged 18-65 years. * BMI 24.0-37.4kg/m²(Chinese standard)。 * Failed prior conservative weight loss attempts ≥2 months。 * Willingness to comply with follow-up. * Provided written informed consent. Exclusion Criteria: * Prior gastrointestinal surgery with clinically relevant sequelae. * Active or clinically significant gastrointestinal disease, including inflammatory conditions (e.g., esophagitis, Barrett's esophagus, Crohn's disease), peptic ulcer disease (gastric/duodenal ulcer), or neoplastic lesions. * Any condition associated with an increased risk of upper gastrointestinal bleeding. * Hiatal hernia \>2 cm or severe/refractory gastroesophageal reflux disease (GERD); acid reflux requiring ≥2 medications for symptom control. * Esophageal/pharyngeal structural abnormalities that may impede endoscope passage (e.g., stricture, diverticulum). * Achalasia or other severe esophageal motility disorder. * Severe coagulopathy. * Insulin-dependent diabetes mellitus. * Chronic abdominal pain. * Gastrointestinal motility disorder (e.g., gastroparesis). * Hepatic impairment or cirrhosis. * Severe or uncontrolled psychiatric illness. * Alcohol abuse or substance dependence. * Unwilling to participate in a physician-supervised diet/behavior modification program and/or unwilling to comply with routine follow-up. * Daily regular use of NSAIDs, anticoagulants, or other gastric-irritating medications. * Unable or unwilling to take proton pump inhibitor (PPI) therapy as prescribed during the treatment period. * Known or suspected hypersensitivity to any material/component of the study system. * Pregnant or breastfeeding. * Severe cardiopulmonary disease or other serious systemic/organic disease. * Positive Helicobacter pylori (H. pylori) test. * Use of time-critical medications potentially affected by altered gastric emptying (e.g., antiepileptics, antiarrhythmics). * Current systemic corticosteroids, immunosuppressants, or opioid analgesics. * Use of any weight-loss medication within the past 3 months or current use. * Prior use of any intragastric device. * Participation in a weight-affecting clinical trial within the past 6 months. * Symptomatic congestive heart failure, clinically significant arrhythmia, or unstable coronary artery disease. * Clinically significant respiratory disease. * Autoimmune connective tissue disease. * Life expectancy \<1 year or severe renal/hepatic/pulmonary or other serious medical illness. * Known genetic or endocrine cause of obesity (e.g., hypothyroidism, Prader-Willi syndrome) or other endocrine disease known to affect body weight. * Eating disorder (e.g., night eating syndrome, bulimia nervosa, binge eating disorder, compulsive eating).

Outcomes

Primary Outcomes

Percent Total Body Weight Loss (%TBWL)

%TBWL = \[(Baseline weight - Follow-up weight) / Baseline weight\] × 100. Measured using calibrated scale under standardized conditions.

Time frame: 1-6 months post-intervention

Clinical Responder Rate (CRR)

Percentage of participants with %TBWL \> 5% at 3/6 months, where %TBWL = \[(baseline weight - month 3/6 weight) / baseline weight\] × 100.

Time frame: 3 month, 6 month

Secondary Outcomes

Body Weight (kg)

Weight measured on a calibrated scale under standardized conditions (light clothing, no shoes, preferably morning after ≥8h fasting).

Time frame: Baseline, 1 month, 2 month, 3 month, 6month

Body Height (m)

Standing height measured with a wall-mounted stadiometer, no shoes, heels together, Frankfurt plane horizontal.

Time frame: Baseline

Percent Excess Body Weight Loss (%EBWL)

%EBWL is calculated as \[(Baseline weight - Follow-up weight) / (Baseline weight - Ideal weight)\] × 100. Ideal weight is defined as the weight corresponding to a BMI of 23.9 kg/m². Weight is measured using a calibrated scale under standardized fasting conditions at each visit.

Time frame: 1-6 months post-intervention

Change in BMI (kg/m²)

BMI will be calculated as weight (kg) divided by height squared (m²).

Time frame: Baseling, 1 month, 2 months, 3 months and 6 months

Glycated Hemoglobin (HbA1c)

HbA1c will be measured using standard laboratory methods. Values at each visit and changes from baseline will be summarized.

Time frame: Baseline, 3 months

Adverse Events (AEs/SAEs) Related to Procedure

Number and proportion of participants with device-/procedure-related AEs/SAEs, graded by Clavien-Dindo and per FDA/ISO definitions.

Time frame: 3, 6, 12 months

GERD-Q Total Score

Gastroesophageal Reflux Disease Questionnaire (GERD-Q) total score, validated 6-item instrument. Higher scores indicate more severe reflux symptoms.

Time frame: Baseline, 3, and 6 months

Postoperative Pain (VAS/NRS)

Patient-reported pain intensity using a 0-10 scale (0=no pain, 10=worst imaginable pain). Assessed at rest.

Time frame: 6 hours, 24 hours, and 7 days

Postoperative Nausea Score

Patient-reported nausea severity using a 0-10 numeric rating scale (0=no nausea, 10=worst nausea).

Time frame: 6 hours, 24 hours, and 7 days

Total Cholesterol

Total cholesterol will be measured after an overnight fast using standard laboratory methods. Values at each visit and changes from baseline will be summarized.

Time frame: Baseline, 3 months

Low-Density Lipoprotein Cholesterol (LDL-C)

LDL-C will be measured directly or calculated using standard methods. Values at each visit and changes from baseline will be summarized.

Time frame: Baseline, 3 months

iWAIST Trial: ERCG (Endoscopic Radial Compression Gastroplasty) vs Optimized Lifestyle Intervention for Weight Loss

Overview

Conditions

Interventions

Eligibility

Locations (2)

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts