Premedication With N-acetylcysteine and Simethicone to Improve Mucosal Visualization in Elective Upper Endoscopy

Official title

Randomized Controlled Trial to Evaluate the Effect of Premedication With N-acetylcysteine and Simethicone on Mucosal Visibility During Elective Upper Gastrointestinal Endoscopy Using the TUGS Score

Overview

The goal of this randomized, double-blind, placebo-controlled clinical trial is to assess whether the combination of N-acetylcysteine and simethicone improves mucosal visibility during upper gastrointestinal endoscopy in adults aged 18 to 99 years of both sexes, including both healthy individuals and those with non-bleeding gastrointestinal symptoms. The main questions this study aims to answer are: Does pre-endoscopy administration of N-acetylcysteine/simethicone improve mucosal visualization based on the Toronto Upper Gastrointestinal Cleanliness Score (TUGS)? Is this combination safe and well tolerated in this patient population? Researchers will compare patients receiving N-acetylcysteine (600 mg) and simethicone (100 mg) orally 20-60 minutes before the procedure with those receiving placebo (water) to determine if there is a significant improvement in TUGS scores. Participants will: Receive a single oral dose of either N-acetylcysteine/simethicone or placebo prior to endoscopy Undergo a routine upper GI endoscopy Have mucosal cleanliness evaluated using the TUGS scoring system Be monitored for any adverse events or intolerance

Detailed description

This is a randomized, double-blind, placebo-controlled, multicenter clinical trial designed to evaluate the efficacy of N-acetylcysteine (NAC) combined with simethicone in improving mucosal visibility during upper gastrointestinal endoscopy (UGIE). The evaluation will be based on the Toronto Upper Gastrointestinal Cleanliness Score (TUGS), a validated tool to assess mucosal cleanliness.

Participants will include adult patients aged 18 to 99 years who are scheduled to undergo diagnostic UGIE for various indications and who do not present with active gastrointestinal bleeding. Eligible participants will be randomized to receive either a single dose of NAC (600 mg) plus simethicone (100 mg) or a placebo (water), administered orally 20 to 60 minutes prior to the procedure. The allocation will be blinded to both participants and endoscopists.

The main objective of the study is to determine whether this premedication protocol results in better mucosal visibility, as measured by the total TUGS score. Secondary objectives include documenting the presence of significant endoscopic findings and histopathological diagnoses, and evaluating the tolerability and safety profile of the premedication.

TUGS scores will be assigned by trained endoscopists blinded to the treatment allocation. Variables such as age, sex, BMI, duration of fasting, hospital site, and endoscope model will be recorded and controlled for in statistical analyses. The study will also assess any potential adverse events associated with the administration of NAC/simethicone.

This study is categorized as Phase 2 because it evaluates the preliminary efficacy and short-term safety of pre-procedural oral N-acetylcysteine (NAC) and simethicone to improve mucosal visibility during diagnostic upper gastrointestinal endoscopy, using the Toronto Upper Gastrointestinal Cleaning Score (TUGCS) as a validated surrogate endpoint. Both agents have established safety profiles for other indications, but their combined use for this indication is not an approved or established standard of care. The trial is randomized, double-blind, placebo-controlled with a moderate sample size designed to estimate effect size and variability rather than to deliver definitive, multi-center confirmatory evidence on hard clinical outcomes.

All procedures will adhere to ethical standards, and informed consent will be obtained from all participants. Data will be collected in a coded, anonymized format and analyzed using appropriate statistical methods, including ANCOVA and non-parametric tests where assumptions of normality are not met.

Interventions

• Drug Premedication with n-acetylcysteine
  Once the sample size has been calculated, patients who meet the inclusion criteria will be recruited. who will be randomized using the "Randomized for Clinical Trial" program for assignment to treatment groups A and B. Group A will receive 600 mg of N-acetylcysteine and 100 mg of simethicone orally 20 to 60 minutes before the procedure, while the control group will receive an equivalent placebo infusion (composed of drinking water). Premedication and placebo will be labeled in containers as medi
• Drug Placebo (drinking water)
  The control group will receive an equivalent placebo infusion (composed of drinking water)
• Drug Premedication with simethicone
  Once the sample size has been calculated, patients who meet the inclusion criteria will be recruited. who will be randomized using the "Randomized for Clinical Trial" program for assignment to treatment groups A and B. Group A will receive 600 mg of N-acetylcysteine and 100 mg of simethicone orally 20 to 60 minutes before the procedure, while the control group will receive an equivalent placebo infusion (composed of drinking water). Premedication and placebo will be labeled in containers as medi

Primary outcome measures

• Total score on the Toronto Upper Gastrointestinal Cleaning Score (TUGCS) [Time frame: During the index upper endoscopy (Day 0), scored intra-procedure (≈20-60 minutes after premedication).]

Secondary outcome measures (5)

• Detection of Mucosal Lesions [Time frame: During endoscopy procedure]
• Complete Esophageal Visualization [Time frame: During endoscopy.]
• Histological gastritis according to the Updated Sydney System (0-3 per item) and OLGA/OLGIM staging (0-IV) [Time frame: Biopsies obtained during the index endoscopy (Day 0); histopathological report within 14 days]
• Presence and density of Helicobacter pylori by histology (Updated Sydney System 0-3) [Time frame: Biopsies obtained during the index endoscopy (Day 0); report within 14 days]
• Number of histologically confirmed neoplasic lesions per patient [Time frame: During the index endoscopy (Day 0) and histological confirmation up to 14 days]

Eligibility criteria

Inclusion criteria

• Men and women aged 18 to 70 years old.
• Patients who agree to participate in the clinical trial.
• Patients without active gastrointestinal bleeding.
• Signing of informed consent form.

Exclusion criteria

• Patients with a history of hypersensitivity to N-acetylcysteine
• Patients with a history of hypersensitivity to simethicone
• Patients with a previous endoscopic diagnosis
• Patients with a history of gastric or bariatric surgery
• Patients with a history of motor disorders (e.g., scleroderma, diabetic gastroparesis)
• Patients taking medications that delay gastric emptying (GLP-1 analogues)
• Pregnant or breastfeeding patients
• Patients who do not agree to participate in the clinical trial

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Triple blind

Primary purpose

Diagnostic

Study locations

Mexico · 2 centers

• Hospital Almater — Mexicali
• Hospital General de Mexicali — Mexicali

Publications

• Devereaux BM, Taylor ACF, Athan E, Wallis DJ, Brown RR, Greig SM, Bailey FK, Vickery K, Wardle E, Jones DM. Simethicone use during gastrointestinal endoscopy: Position statement of the Gastroenterological Society of Australia. J Gastroenterol Hepatol. 2019 Dec;34(12):2086-2089. doi: 10.1111/jgh.14757. Epub 2019 Jul 28. PMID 31242327
• Manfredi G, Berte R, Iiritano E, Alicante S, Londoni C, Brambilla G, Romeo S, Menozzi F, Griffanti P, Brandi G, Moreschi O, Pezzilli R, Zullo A, Buscarini E. Premedication with simethicone and N-acetylcysteine for improving mucosal visibility during upper gastrointestinal endoscopy in a Western population. Endosc Int Open. 2021 Feb;9(2):E190-E194. doi: 10.1055/a-1315-0114. Epub 2021 Jan 25. PMID 33532557
• Monrroy H, Vargas JI, Glasinovic E, Candia R, Azua E, Galvez C, Rojas C, Cabrera N, Vidaurre J, Alvarez N, Gonzalez J, Espino A, Gonzalez R, Parra-Blanco A. Use of N-acetylcysteine plus simethicone to improve mucosal visibility during upper GI endoscopy: a double-blind, randomized controlled trial. Gastrointest Endosc. 2018 Apr;87(4):986-993. doi: 10.1016/j.gie.2017.10.005. Epub 2017 Oct 14. PMID 29037773
• Beaufort IN, Verbeek RE, Bosman JH, Al-Toma A, Bogte A, Alvarez Herrero L, Weusten BLAM. Optimal timing of simethicone administration prior to upper endoscopy: A multicenter, single-blind, randomized controlled trial. Endosc Int Open. 2023 Oct 17;11(10):E992-E1000. doi: 10.1055/a-2157-5034. eCollection 2023 Oct. PMID 37854124
• Mahawongkajit P, Kanlerd A. A prospective randomized controlled trial comparing simethicone, N-acetylcysteine, sodium bicarbonate and peppermint for visualization in upper gastrointestinal endoscopy. Surg Endosc. 2021 Jan;35(1):303-308. doi: 10.1007/s00464-020-07397-8. Epub 2020 Feb 3. PMID 32016519
• Chang WK, Yeh MK, Hsu HC, Chen HW, Hu MK. Efficacy of simethicone and N-acetylcysteine as premedication in improving visibility during upper endoscopy. J Gastroenterol Hepatol. 2014 Apr;29(4):769-74. doi: 10.1111/jgh.12487. PMID 24325147
• Sajid MS, Rehman S, Chedgy F, Singh KK. Improving the mucosal visualization at gastroscopy: a systematic review and meta-analysis of randomized, controlled trials reporting the role of Simethicone +/- N-acetylcysteine. Transl Gastroenterol Hepatol. 2018 May 19;3:29. doi: 10.21037/tgh.2018.05.02. eCollection 2018. PMID 29971260
• Li Y, Du F, Fu D. The effect of using simethicone with or without N-acetylcysteine before gastroscopy: A meta-analysis and systemic review. Saudi J Gastroenterol. 2019 Jul-Aug;25(4):218-228. doi: 10.4103/sjg.SJG_538_18. PMID 31044749

Identifiers

NCT: NCT07245095 · NACSIMET-ETDA-MEX2025

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗