HealthyiPROACT-pilot2NCT07105514
Indole-3-PROpionic Acid Clinical Trials - a Pilot Study Part 2
A study testing Indole-3-propionic acid (IPA) in people with Healthy, run by Glostrup University Hospital, Copenhagen at 1 site in Denmark.
Trial summary
The goal of this trial is to investigate the biological effects of oral supplementation with indole-3-propionic acid (IPA) taken twice daily in healthy adults. The main scientific questions are: Does supplementation with IPA increase the abundance of regulatory T cells in the blood? Regulatory T cells are believed to… Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy
- What is being tested?
- Indole-3-propionic acid (IPA)
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 32 participants
- Where
- 1 siteDenmark
- Study dates
- 4 Aug 2025to 30 Jun 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy women and men ≥18 and ≤65 years of age
- Deemed mentally and physically able to participate
Who cannot join
- Diagnosis of gut-, heart-, liver-, kidney or immune-related disorders
- Use of antibiotics within the last month
- Pregnancy, lactation or childbirth within the last five months
- Use of prescription medication
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Denmark1 site, 1 recruiting
- Recruiting
Optic Neuritis Clinic, Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital, Rigshospitalet-Glostrup
Glostrup Municipality, 2600
Jette Lautrup Frederiksen, Prof, MD, +4538633041, jette.lautrup.battistini@regionh.dk
Jette Lautrup Frederiksen, Prof, MD
About this study
Official title: Indole-3-PROpionic Acid Clinical Trials - a Pilot Study Part 2 (iPROACT-pilot2)
The goal of this trial is to investigate the biological effects of oral supplementation with indole-3-propionic acid (IPA) taken twice daily in healthy adults. The main scientific questions are:
- Does supplementation with IPA increase the abundance of regulatory T cells in the blood? Regulatory T cells are believed to play an important role in preventing autoimmune diseases.
- Does supplementation with IPA increase the concentration of brain-derived neurotrophic factor (BDNF) in the blood? BDNF is believed to play an important role in maintaining brain health.
- Does supplementation with IPA affect blood analyses commonly performed to assess the risk of metabolic disorders like type 2 diabetes and cardiovascular diseases?
Read more
Participants will:
- Take capsules to achieve a total daily dose of 1000 mg of IPA or placebo: 500 mg every morning and 500 mg every evening for 14 days.
- Visit the clinic at the beginning (day 1) and at the end (day 15) of the supplementation period to deliver blood, urine and fecal samples, have simple measurements performed, fulfil questionnaires and report any side effects.
Read the detailed description
Indole-3-propionic acid (IPA) is a gut bacterial metabolite with the amino acid tryptophan as substrate. In vitro and animal studies suggest that IPA could contribute to regulating inflammation and metabolic function, preventing oxidative damage and upregulating expression of brain-derived neurotrophic factor. With this study we aim to investigate the biochemical effects of IPA at supraphysiological levels in humans.
- Conditions
- Healthy
- Being tested
- Indole-3-propionic acid (IPA), Placebo
- Keywords
- indole-3-propionic acid, gut bacterial metabolite, regulatory T cells, brain-derived neurotrophic factor, dietary supplement
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Indole-3-propionic acid (IPA)Dietary supplement
Two capsules are taken every morning and two capsules are taken every evening for 14 consecutive days. Active capsules are taken orally and contain 250 mg of IPA each.
PlaceboDietary supplement
Two capsules are taken every morning and two capsules are taken every evening for 14 consecutive days. Placebo capsules are taken orally and contain maltodextrin.
| Study group | Role | What they receive |
|---|---|---|
| Placebo | Placebo comparator | Placebo Receives: Dietary Supplement: Placebo |
| Indole-3-propionic acid (IPA) | Experimental | IPA: total daily dose of 1000 mg Receives: Dietary Supplement: Indole-3-propionic acid (IPA) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Regulatory T cells (first primary outcome)
FoxP3+CD25+CD127- regulatory T cells expressed as a percentage of single, live CD3+CD4+CD8- lymphocytes. Analysed in freshly isolated peripheral blood mononuclear cells using a Symphony A3 flowcytometer.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Brain-derived neurotrophic factor (second primary outcome)
Brain-derived neurotrophic factor measured in platelet-free plasma samples using ELISA or mesoscale.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Secondary outcomes (30)
Th1/Th2 ratio in PBMCs
Th1/Th2 ratio calculated from T cell profiling of freshly isolated peripheral blood mononuclear cells (PBMCs) using a Symphony A3 flowcytometer.
Th1 cells are defined as the CXCR3+CCR4-CCR6-CCR10- non-Treg population and expressed as a percentage of single, live CD3+CD4+CD8-CD45RA- lymphocytes.
Th2 cells are defined as the CXCR3-CCR4+CCR6-CCR10- non-Treg population and expressed as a percentage of single, live CD3+CD4+CD8-CD45RA- lymphocytes.
Panel antigens: FVS780, CD3, CD4, CD8, CD45RA, CCR7, CXCR3, CCR6, CCR4, CCR10, CD25, CD127, FoxP3.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Th17/mTreg ratio in PBMCs
Th17/mTreg ratio calculated from T cell profiling of freshly isolated peripheral blood mononuclear cells (PBMCs) using a Symphony A3 flowcytometer.
Th17 cells are defined as the CXCR3-CCR4+CCR6+CCR10- non-Treg population and expressed as a percentage of single, live CD3+CD4+CD8-CD45RA- lymphocytes.
mTreg (memory Tregs) are defined as the FoxP3+CD25+CD127-CD45RA- population and expressed as a percentage of single, live CD3+CD4+CD8-CD45RA- lymphocytes
Panel antigens: FVS780, CD3, CD4, CD8, CD45RA, CCR7, CXCR3, CCR6, CCR4, CCR10, CD25, CD127, FoxP3.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Th17.1 cells in PBMCs
Th17.1 cells in freshly isolated peripheral blood mononuclear cells (PBMCs) characterized using a Symphony A3 flowcytometer.
Th17.1 cells are defined as the CXCR3+CCR4-CCR6+CCR10- non-Treg population and expressed as a percentage of single, live CD3+CD4+CD8-CD45RA- lymphocytes
Panel antigens: FVS780, CD3, CD4, CD8, CD45RA, CCR7, CXCR3, CCR6, CCR4, CCR10, CD25, CD127, FoxP3.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
CRP
C-reactive protein (CRP) measured in plasma (mg/L) as a biomarker of infection and systemic inflammation. Lower-limit of quantification: 0,4 mg/L. Values below 0,4 mg/L are imputed as 0,2 mg/L.
Measured: Results from blood samples taken on day 15 (just before last supplement/placebo dose) and adjusted for results from day 1 (just before first supplement/placebo dose).
Triglycerides
Plasma triglycerides (mmol/l).
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
non-HDL cholesterol
Non-HDL cholesterol calculated as total cholesterol minus HDL cholesterol (mmol/l)
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
C-peptide
Proinsulin C-peptide (pmol/l) measured in plasma.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Fasting glucose
Plasma glucose (mmol/l). Participants abstain from eating and drinking after 22.00 the day before. Only water is allowed. Fasting blood samples are taken between 8.00-10.00 in the morning.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
F2-isoprostanes
F2-isoprostanes with a specific focus on 8-iso-prostaglandin F2α measured in blood or morningurine samples as a marker of lipid oxidation.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
8-oxo-dG
8-oxo-dG (8-Oxo-2'-deoxyguanosine) measured in blood or morningurine samples as a marker of DNA-related stress damage.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Serum metabolomics
Targetted and untargetted liquid-chromatography mass-spectrometry-based metabolomics of serum samples. Targetted analyses aim to quantify indole-3-propionic acid and its metabolites (biomarker of compliance as well as absorptive and metabolic capacity), other bacterial- and host metabolites of tryptophan as well as short-chain fatty acids.
Measured: Four samples in total. Day 1 prior to and again 1.5 hour after intake of first capsule of IPA/ placeblo. Day 15 prior to and again 1.5 hour after intake of last capsule of IPA/ placebo.
Total cholesterol
Plasma cholesterol (mmol/l).
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
VLDL cholesterol
Plasma very low-density lipoproteins (mmol/l).
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
LDL cholesterol
Plasma low-density lipoprotein (LDL) (mmol/l).
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
HDL cholesterol
Plasma high-density lipoprotein (HDL) (mmol/l).
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Malondialdehyde
Malondialdehyde measured in blood or morningurine samples as a marker of oxidative stress.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Protein carbonyls
Protein carbonyls measured in blood or morningurine samples as a marker of protein oxidation.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Glycated hemoglobin (HbA1c)
HbA1c (IFCC, mmol/mol) measured in whole blood. Estimated average glucose values (mmol/l) are also calculated automatically from HbA1c by our laboratory.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
T cell profiling
Targetted and untargetted T cell profiling of freshly isolated peripheral blood mononuclear cells (PBMCs) using a Symphony A3 flowcytometer. Panel antigens: FVS780, CD3, CD4, CD8, CD45RA, CCR7, CXCR3, CCR6, CCR4, CCR10, CD25, CD127, FoxP3.
Target populations:
Naïve: CD45RA+CCR7+, Central memory: CD45RA-CCR7+, Effector memory: CD45RA-CCR7-, TEMRA: CD45RA+CCR7-, Th1: CXCR3+CCR4-CCR6-CCR10-, Th2: CXCR3-CCR4+CCR6-CCR10-, Th17: CXCR3-CCR4+CCR6+CCR10-, Th17.1: CXCR3+CCR4-CCR6+CCR10-, Th22: CXCR3-CCR4+CCR6+CCR10+, as well as expression of chemokine receptors on cytotoxic T cells and regulatory T cells.
An untargetted approach may be employed to allow for unbiased identification of changes in novel, yet uncharacterized populations.
Measured: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Changes in the gut microbiome
Characterization of the gut microbiome using molecular biology methods such as 16s rRNA sequencing.
Measured: Fecal samples are collected at three time points: prior to supplementation (earliest 48 hours prior to first visit (day 1)), short after initiation of supplementation (day 3 or soonest thereafter) and again earliest 48 hours prior to last visit.
Characterization of the metabolic activity of the gut microbiota
Targetted and untargetted liquid-chromatography mass-spectrometry-based metabolomics. Targetted analyses aim to quantify indole-3-propionic acid, other bacterial- and host metabolites of tryptophan as well as short-chain fatty acids.
Measured: Fecal samples are collected at three time points: prior to supplementation (earliest 48 hours prior to first visit (day 1)), short after initiation of supplementation (day 3 or soonest thereafter) and again earliest 48 hours prior to last visit.
Bacterial polysaccharides
Endotoxin, capsular polysaccharides or other bacterial polysaccharides measured in blood samples as biomarker of bacterial translocation across the intestinal epithelium.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Pre-haptoglobin 2
Measurement of pre-haptoglobin 2 in blood samples as a biomarker of intestinal permeability.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Intestinal fatty acid binding protein
Measurements of intestinal fatty acid binding protein in blood samples as a biomarker of enterocyte damage.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Citrulline
Measurement of citrulline in blood samples as a biomarker of intestinal function.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Calprotectin
Calprotectin measured in fecal samples as a biomarker of intestinal inflammation.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Neopterin
Neopterin measured in morningurine samples as a biomarker of systemic inflammation.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
suPAR
Soluble urokinase plasminogen activator receptor (suPAR) measured in blood samples.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Microvesicles
Flow cytometric analyses of microvesicles/ microparticles in platelet-free plasma as biomarker of systemic inflammation.
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Endothelial progenitor cells
Flow cytometric analyses of endothelial progenitor cells measured in platelet-free plasma as biomarker of systemic inflammation
Measured: Results from samples taken on day 15 and adjusted for results from day 1.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Aug 2025
- Study start4 Aug 2025
- Primary completion30 Oct 2025 (estimated)
- Study completion30 Jun 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HealthyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 32 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Glostrup University Hospital, Copenhagen
- Sponsor type
- University, hospital or other
- Collaborators
- University of Copenhagen, University of Southampton
- Responsible party
- Principal investigator, Jette Lautrup Frederiksen, Glostrup University Hospital, Copenhagen
- Investigators
- Jette Frederiksen, Prof, MD, Principal investigator, Copenhagen University Hospital, Rigshospitalet-Glostrup
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07105514
- Sponsor's protocol ID
- H-24008127 - 116180
- Acronym
- iPROACT-pilot2
- Status last verified
- Aug 2025
- First submitted
- 17 Jul 2025
- Last updated
- 8 Aug 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Individual participant data that underlie the results reported in published articles, after deidentification (text, tables, figures, and appendices).
Study at a glance
From the registry record, last updated by the sponsor on 8 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Indole-3-PROpionic Acid Clinical Trials - a Pilot Study Part 2 (iPROACT-pilot2)
- ClinicalTrials.gov ID
- NCT07105514
- Acronym / sponsor ID
- iPROACT-pilot2 / H-24008127 - 116180
- Conditions
- Healthy
- Keywords
- indole-3-propionic acid, gut bacterial metabolite, regulatory T cells, brain-derived neurotrophic factor, dietary supplement
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 32 participants (estimated)
- Lead sponsor
- Glostrup University Hospital, CopenhagenUniversity, hospital or other
- Collaborators
- University of Copenhagen, University of Southampton
- Study start
- 4 Aug 2025 (actual)
- Primary completion
- 30 Oct 2025 (estimated)
- Study completion
- 30 Jun 2026 (estimated)
- First posted
- 6 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this trial is to investigate the biological effects of oral supplementation with indole-3-propionic acid (IPA) taken twice daily in healthy adults. The main scientific questions are:
- Does supplementation with IPA increase the abundance of regulatory T cells in the blood? Regulatory T cells are believed to play an important role in preventing autoimmune diseases.
- Does supplementation with IPA increase the concentration of brain-derived neurotrophic factor (BDNF) in the blood? BDNF is believed to play an important role in maintaining brain health.
- Does supplementation with IPA affect blood analyses commonly performed to assess the risk of metabolic disorders like type 2 diabetes and cardiovascular diseases?
Participants will:
- Take capsules to achieve a total daily dose of 1000 mg of IPA or placebo: 500 mg every morning and 500 mg every evening for 14 days.
- Visit the clinic at the beginning (day 1) and at the end (day 15) of the supplementation period to deliver blood, urine and fecal samples, have simple measurements performed, fulfil questionnaires and report any side effects.
Detailed description
Indole-3-propionic acid (IPA) is a gut bacterial metabolite with the amino acid tryptophan as substrate. In vitro and animal studies suggest that IPA could contribute to regulating inflammation and metabolic function, preventing oxidative damage and upregulating expression of brain-derived neurotrophic factor. With this study we aim to investigate the biochemical effects of IPA at supraphysiological levels in humans.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Placebo | Placebo comparator | Dietary Supplement: PlaceboPlacebo |
| Indole-3-propionic acid (IPA) | Experimental | Dietary Supplement: Indole-3-propionic acid (IPA)IPA: total daily dose of 1000 mg |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Healthy women and men ≥18 and ≤65 years of age
- Deemed mentally and physically able to participate
Key exclusion criteria (4 listed)
- Diagnosis of gut-, heart-, liver-, kidney or immune-related disorders
- Use of antibiotics within the last month
- Pregnancy, lactation or childbirth within the last five months
- Use of prescription medication
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Indole-3-propionic acid (IPA)Two capsules are taken every morning and two capsules are taken every evening for 14 consecutive days. Active capsules are taken orally and contain 250 mg of IPA each. | Dietary supplement | Indole-3-propionic acid (IPA) |
| PlaceboTwo capsules are taken every morning and two capsules are taken every evening for 14 consecutive days. Placebo capsules are taken orally and contain maltodextrin. | Dietary supplement | Placebo |
Primary outcome
Regulatory T cells (first primary outcome)
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
FoxP3+CD25+CD127- regulatory T cells expressed as a percentage of single, live CD3+CD4+CD8- lymphocytes. Analysed in freshly isolated peripheral blood mononuclear cells using a Symphony A3 flowcytometer.
Brain-derived neurotrophic factor (second primary outcome)
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Brain-derived neurotrophic factor measured in platelet-free plasma samples using ELISA or mesoscale.
30 secondary outcomes
Th1/Th2 ratio in PBMCs
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Th17/mTreg ratio in PBMCs
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Th17.1 cells in PBMCs
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
CRP
Time frame: Results from blood samples taken on day 15 (just before last supplement/placebo dose) and adjusted for results from day 1 (just before first supplement/placebo dose).
Triglycerides
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
non-HDL cholesterol
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
C-peptide
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Fasting glucose
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
F2-isoprostanes
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
8-oxo-dG
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Serum metabolomics
Time frame: Four samples in total. Day 1 prior to and again 1.5 hour after intake of first capsule of IPA/ placeblo. Day 15 prior to and again 1.5 hour after intake of last capsule of IPA/ placebo.
Total cholesterol
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
VLDL cholesterol
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
LDL cholesterol
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
HDL cholesterol
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Malondialdehyde
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Protein carbonyls
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Glycated hemoglobin (HbA1c)
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
T cell profiling
Time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).
Changes in the gut microbiome
Time frame: Fecal samples are collected at three time points: prior to supplementation (earliest 48 hours prior to first visit (day 1)), short after initiation of supplementation (day 3 or soonest thereafter) and again earliest 48 hours prior to last visit.
Characterization of the metabolic activity of the gut microbiota
Time frame: Fecal samples are collected at three time points: prior to supplementation (earliest 48 hours prior to first visit (day 1)), short after initiation of supplementation (day 3 or soonest thereafter) and again earliest 48 hours prior to last visit.
Bacterial polysaccharides
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Pre-haptoglobin 2
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Intestinal fatty acid binding protein
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Citrulline
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Calprotectin
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Neopterin
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
suPAR
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Microvesicles
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Endothelial progenitor cells
Time frame: Results from samples taken on day 15 and adjusted for results from day 1.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Aug 2025.
- Individual participant dataSharing planned: Yes. Individual participant data that underlie the results reported in published articles, after deidentification (text, tables, figures, and appendices).
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Jette Frederiksen, Prof, MD principal investigator
Copenhagen University Hospital, Rigshospitalet-Glostrup
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Indole-3-propionic acid (IPA) in people with Healthy, run by Glostrup University Hospital, Copenhagen at 1 site in Denmark.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 8 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Moschoula Passali, MSc, PhD (+45 38633467, moschoula.passali@regionh.dk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Regulatory T cells (first primary outcome) (time frame: Results from fasting blood samples taken on day 15 and adjusted for results from day 1 (fasting just before first supplement/placebo dose).). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Aug 2025.