An interventional study of 9.9 x 10^7 Pichia kluyveri PK88 and 1 x 10^8 Pichia kluyveri PK88 in Healthy Adult Participants and Gut Health, sponsored by Colorado State University. Not yet recruiting at 1 site in United States. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-22.
Sponsored by Colorado State University · Not applicable, Interventional, and Supportive care
The purpose of this study is to evaluate the tolerability and efficacy of a yeast-based dietary supplement on gastrointestinal, mental, and skin health. Yeasts are naturally present on fruits and plants, and are used to bake bread, beer and wine. Some of these yeasts are commonly consumed and may actually benefit your gut health. The supplemental yeast could strengthen the gut lining or help good bacteria in the gut grow better.
In this study, the investigators will look at how two doses of a yeast-based supplement impacts gut health, bowel movement consistency, and mental health. The study will last 17 weeks and consist of 7 clinic visits (1 screening visit and 6 test visits).
This study will take place at Colorado State University in Fort Collins, Colorado, USA. It will last approximately 17 weeks. This is a randomized, double-blind 3-arm crossover study with three treatments (placebo and two doses of Pichia kluyveri). The treatments will be taken for 4 weeks in a random order by every participant. Each treatment phase is separated by a 2-week washout. The first visit is a screening visit, where investigators will determine eligibility. Visit 2-7 are test visits where investigators will collect information on height, weight, waist, and hip measurements. Blood pressure will also be measured and the visit will conclude with a venous blood draw. During this visit, participants will also complete questionnaires about gut, mental, and skin health, menopause symptoms, and physical activity. A stool sample and bowel movement and diet records will be completed at home.
Colorado State University is the lead sponsor of 116 studies on the registry; 20 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 3 (60%) have results posted.
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Exclusion Criteria:
Dietary Supplement: 9.9 x 10^7 Pichia kluyveri PK88
Dietary Supplement: 1 x 10^8 Pichia kluyveri PK88
Dietary Supplement: Placebo
9.9 x 10\^7 Pichia kluyveri in microcrystalline cellulose and hypromellose
1 x 10\^8 Pichia kluyveri in microcrystalline cellulose and hypromellose
Placebo - cellulose and hypromellose
Severity of gastrointestinal symptoms using the Gastrointestinal Symptom Rating Scale (GSRS)
The Gastrointestinal Symptom Rating Scale (GSRS) is a widely used tool for measuring gastrointestinal symptoms across five domains. The GSRS is scored between "No discomfort" and "Very severe discomfort"
Time frame: 4 weeks
Systemic inflammation indicated by circulating Tumor Necrosis Factor Alpha
Tumor necrosis factor alpha, or TNF-a, is an inflammatory cytokine that is implicated in many diseases.
Time frame: 4 weeks
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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