NCT06433310 · Weill Medical College of Cornell University
Understanding the Efficacy of Dietary Supplement on Fungal Mycobiota in Healthy Volunteers: A Pilot Study
What this study is about
The purpose of this study is to explore how the dietary supplement L-Phenylalanine affects the production of the metabolite phenylpropionic acid (PPA) and changes fungal populations of the gut microbiome.
View original scientific description
The purpose of this study is to explore how the dietary supplement L-Phenylalanine affects the production of the metabolite phenylpropionic acid (PPA) and changes fungal populations of the gut microbiome.
Interventions
DRUG
L-Phenylalanine 500 mg Veg Capsule product
500 mg Veg Capsule product
Primary outcome measures
Changes in phenylpropionic acid levels from baseline in subject fecal material
Time frame: Baseline, Week 2 (Day 14)
Metabolite phenylpropionic acid levels will be measured using mass spectrometry before (baseline) and after intervention
Change in fungal population levels, specifically gut Candida levels, from baseline in subject fecal material and swabs
Time frame: Baseline, Week 2 (Day 14)
Fungal populations, including Candida, will be measured using microbiota sequencing before (baseline) and after intervention. The most abundant fungal populations will be reported; however, the identity of those populations won't be known until sample analysis.
Change in the number of T cells that react to fungal antigens from baseline in subject blood samples
Time frame: Baseline, Week 2 (Day 14)
Blood will be processed through ELISA-based and in vitro restimulation assays to measure T cell reactivity to fungal antigens
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Male or female adults over the age of 18 years
Exclusion criteria
- History of a diagnosis of any gastrointestinal condition, such as inflammatory bowel syndrome or disease
- Antibiotic usage within the past two weeks
- Antifungal usage within the past month
- Allergy to L-Phenylalanine or individuals with phenylketonuria (PKU)
- Adults taking medications known to interact with L-phenylalanine supplements, such as Monoamine Oxidase Inhibitors (MOAI), L-DOPA, and some antipsychotic drugs (complete and extensive drug list will be provided to interested participants during screening)
- Pregnant or nursing women
Where
- New York, New York
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 26, 2026 · Source of record for eligibility and locations