Recruiting

Dietary Supplement

Sponsor:

Weill Medical College of Cornell University

Code:

NCT06433310

Conditions

Gut Microbiome

Gut Health

Dietary Supplement

L-Phenylalanine

Phenylpropionic Acid

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Accepted

Interventions

L-Phenylalanine 500 mg Veg Capsule product

Study Details

Brief summary:

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.

Conditions

Gut Microbiome

Gut Health

Dietary Supplement

L-Phenylalanine

Phenylpropionic Acid

Study ID

NCT06433310

Start date

Oct 17, 2024

Status verified date

Jun, 2026

Completion date

Dec 31, 2027

Anticipated

Primary completion date

Dec 17, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Accepted

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

Study Design

Enrollment

20 participants

Anticipated

Intervention Model

Single group

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Healthy

Participants will receive one bottle of L-Phenylalanine 500 mg Veg Capsule product on Day 0. All subjects will be asked to start taking the supplement on Day 1 continuing until Day 14. They will be asked to take 2x 500 mg capsules in the morning and 1x 500 mg capsule in the evening daily for 14 days.

Interventions

L-Phenylalanine 500 mg Veg Capsule product

500 mg Veg Capsule product

Primary outcome measure

  • Changes in phenylpropionic acid levels from baseline in subject fecal material [ Time Frame: Baseline, Week 2 (Day 14) ]
  • Change in fungal population levels, specifically gut Candida levels, from baseline in subject fecal material and swabs [ Time Frame: Baseline, Week 2 (Day 14) ]
  • 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) ]

Central Contacts and Locations

Central contacts

Emilia T Vignogna, BS

505-259-4995etv4001@med.cornell.edu

Tsering D Sherpa-Ngima, BSc

929-328-9571tss4002@med.cornell.edu

Locations

Belfer Research Building

Recruiting

New York, New York, United States, 10022

Contacts

Emilia T Vignogna, BS

505-259-4995etv4001@med.cornell.edu

Principal Investigator:

Iliyan D Iliev, PhD

More Information

Sponsor

Weill Medical College of Cornell University

Last update posted

Jun 26, 2026

Last verified

Jun, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Weill Medical College of Cornell University on 2026-06-26.