A Phase 2 interventional study of Colesevelam and Placebo in PFAS, Environmental Exposures and Occupational Exposure to Chemicals, sponsored by University of Rhode Island. Not yet recruiting at 3 sites in United States. Open to participants aged 25 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-18.
Sponsored by University of Rhode Island · Phase 2, Interventional, and Treatment
The goal of this study is to test the efficacy and feasibility of Colesevelam administration (50% of the recommended dose) to reduce serum PFAS concentration in the Veteran population who have serum PFAS levels that exceed the National Academies Science criteria (PFASsix > 20 ng/ml) using a double blind-placebo controlled study. Based on PFAS prevalence in serum samples, we anticipate recruiting up to n=500 Veterans to meet the goal of n=50 study participants to receive intervention or placebo. The primary outcome will be initial and final PFAS content in serum (total and 7 individual PFAS). The secondary outcome will be initial and final serum biomarkers related to lipid metabolism. As an exploratory aspect to the proposal, we will also measure fecal PFAS, bile acids, and microbial diversity to examine associations between PFAS content and bile acid levels and microbiome. Fecal PFAS, bile acid content, and microbiome may also be measured.
This double-blind randomized controlled trial has a extended open phase to test the use of oral Colesevelam (3 x 625 mg tablets qd) for 12 weeks to lower total serum PFAS levels in individuals with >20 ng/ml PFAS. After 12 weeks, participants assigned to placebo will have an opportunity to participate in the intervention of 12 weeks. Participants on the intervention will remain on the intervention for another 24 weeks.
1,175 studies on the registry are indexed under Hypercholesterolemia; 93 are open to participants now.
This study's planned enrollment of 50 is below the median of 110 across 975 interventional studies indexed under Hypercholesterolemia.
Browse Hypercholesterolemia studies →University of Rhode Island is the lead sponsor of 34 studies on the registry; 6 are open to participants now.
Compared within Hypercholesterolemia, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Hyperlipidemias. The counts are of registry records indexed under each term, refreshed daily. How we classify →
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Oral Colesevelam (3 x 625 mg tablets daily) for 12 weeks
Drug: Colesevelam
Oral placebo (3 x 250 mg once daily) for 12 weeks
Drug: Placebo
A double-blind randomized controlled trial with an extended open phase to test the use of oral Colesevelam (3 x 625 mg tablets daily) for 12 weeks
A double-blind randomized controlled trial with an extended open phase to test the use of oral Colesevelam
PFAS content
Reduction PFAS content in serum (total and 7 individual PFAS).
Time frame: 24 weeks
Serum biomarkers
The secondary outcome will be initial and final serum biomarkers related to lipid metabolism.
Time frame: 24 weeks
Exploratory
As an exploratory aspect to the proposal, we will also measure fecal PFAS, bile acids, and microbial diversity to examine associations between PFAS content and bile acid levels and microbiome.
Time frame: 24 weeks
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Jul 2026; primary completion for Apr 2029, 33 months later.
Of 48 phase 2 interventional studies under Hypercholesterolemia, half reached primary completion within 10 months of starting (the median), counting those still running; a quarter within 7 and three quarters within 18. This study's planned 33 months is above that.
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This study is not yet recruiting, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Colesevelam
University of Rhode Island