Independent directory Public ClinicalTrials.gov records United States
ClinicalTrials.gov record
Completed Phase 4 Interventional Accepts healthy volunteers Results available

Effects of Gastric Acid on Colonic Microbiome

ClinicalTrials.gov ID: NCT01901276

Public ClinicalTrials.gov record NCT01901276. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 10, 2026, 12:13 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

The Effects of Gastric Acid Suppression on the Colonic Microbiome

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

The colonic microbiome is essential in human health and disease. Clostridium difficile-associated diarrhea (CDAD), a highly morbid form of infectious diarrhea, is caused by antibiotics which perturb the microbiome and allow C. difficile to proliferate. Proton pump inhibitors (PPIs) are powerful suppressors of gastric acid and among the most common medicines in the United States. Dozens of observational studies show that longterm PPI use is associated with CDAD. However, the mechanism by which PPIs cause CDAD is unknown. We believe that PPIs cause CDAD by inducing alterations in the human colonic microbiome. We will confirm or refute the hypothesized mechanism for the association between PPIs and CDAD using an unblinded, single-armed study design. We will use pyrosequencing of the hypervariable V4 region of the bacterial 16S ribosomal subunit gene in human fecal samples to describe the colonic flora. We will collect fecal samples from volunteers before and after PPIs given for different durations and test the microbiome to determine 1) whether PPIs diminish overall diversity, 2) whether PPIs diminish relative abundance of Bacteroidetes, 3) whether increased duration of PPIs affects diversity, and 4) whether there is recovery of diversity after completing a defined course of PPIs. We believe that PPIs will cause a pattern of diminished overall microbiome diversity and reduced anaerobes - the same pattern seen after use of antibiotics. Furthermore, we believe that increased PPI duration will further diminish diversity and that the microbiome will return to pre-PPI levels of diversity after PPIs are stopped. These results will facilitate biologically-based clinical interventions to reduce rates of CDAD among patients who require acid suppression.

Study identification

NCT ID
NCT01901276
Recruitment status
Completed
Study type
Interventional
Phase
Phase 4
Lead sponsor
Daniel Freedberg, MD
Other
Enrollment
14 participants

Conditions and interventions

Interventions

Drug

Eligibility (public fields only)

Age range
18 Years and older
Sex
Male
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Jul 31, 2013
Primary completion
Feb 28, 2015
Completion
Feb 28, 2015
Last update posted
Aug 14, 2024

2013 – 2015

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Columbia University New York New York 10032

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

Recently updated Clostridium Difficile trials

Other public records listing Clostridium Difficile. Sorted by last update posted; newest first. Not a recommendation.

All Clostridium Difficile trials →

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT01901276, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Aug 14, 2024 · Synced Sep 10, 2026

Related: full search, browse by condition, browse by drug or therapy, browse by sponsor, browse by U.S. city.

Open the official record

The complete protocol, eligibility criteria, and contact information for NCT01901276 live on ClinicalTrials.gov.

View official ClinicalTrials.gov record →