Evaluating how PEG bowel preparation affects gut microbiome recovery

Impact of PEG Bowel Preparation on Gut Microbiome Composition Recovery

PHASE1 · Centre hospitalier de l'Université de Montréal (CHUM) · NCT06831539

This study is testing how a bowel prep using PEG affects the gut bacteria in people to see if it changes their diversity and composition.

Quick facts

PhasePHASE1
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years to 70 Years
SexAll
SponsorCentre hospitalier de l'Université de Montréal (CHUM) (other)
Locations1 site (Montreal, Quebec)
Trial IDNCT06831539 on ClinicalTrials.gov

What this trial studies

This study aims to assess the effects of PEG bowel preparation on the composition and diversity of the gut microbiome. It will utilize metagenomic shotgun sequencing to analyze changes in microbiota before and after bowel preparation. The research addresses concerns regarding the potential negative impact of PEG on immune checkpoint inhibitor efficacy and seeks to establish a gold-standard control for future microbiome-centered trials.

Who should consider this trial

Good fit: Ideal candidates for this study are healthy adults over 18 years old who can provide informed consent and complete the PEG bowel preparation.

Not a fit: Patients with recent cancer treatment, significant gastrointestinal conditions, or contraindications to PEG bowel preparation may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance our understanding of gut microbiome recovery, potentially improving treatment outcomes for patients undergoing bowel preparation.

How similar studies have performed: While there is limited literature on the impact of PEG on the microbiome, this study aims to fill a gap in understanding, making it a novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Healthy volunteer participant cohort:

  1. \> 18 years of age
  2. The participant has provided documented informed consent for the participation and to complete PEG bowel preparation and return collected stool samples.

Exclusion Criteria:

* An ileus
* Significant gastric retention
* Suspected or established mechanical bowel obstruction
* Inflammatory or infectious gastrointestinal condition
* Neurologic or cognitive impairment that prevents safe swallowing
* Recent history (\<1 year) of cancer that still requires ongoing treatment
* Recent use of antibiotics 1 month prior to participation in the trial
* History of cardiac disease
* History of active renal dysfunction
* Presence of any absolute contraindication to PEG bowel preparation according to manufacturer labeling

Where this trial is running

Montreal, Quebec

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Cancer, Healthy Participants, PegLyte, Microbiome

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.