Hypovitaminosis DNCT07199829
Evaluating Response to Vitamin D3 and K2 Supplementation in Healthcare Personnel
A study testing Vitamin Arm 1, Vitamin Arm 2 and Vitamin Arm 3 in people with Hypovitaminosis D and Hypovitaminosis, run by Madigan Army Medical Center at 1 site in United States.
Trial summary
The main purpose of this research study is to learn about the effects of supplemental vitamin D3 and vitamin K2 on blood levels and the gut microbial community, called the gut microbiome. Read more about this study
- Who is it for?
- Ages 18 to 69 yearsHealthy volunteers can take part
- Conditions the study is for
- Hypovitaminosis D, Hypovitaminosis
- What is being tested?
- Vitamin Arm 1, Vitamin Arm 2 and Vitamin Arm 3
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 96 participants
- Where
- 1 siteUnited States
- Study dates
- 27 Mar 2025to Mar 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 69 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- able to read and understand English
- 25 OHD serum level equal to or less than 30 ng/mL
- willing to discontinue vitamin D3 and/or K2 supplements for 4.5 months
- military beneficiary (Active Duty, Retired, Dependent)
- remaining employed at workplace for 6 months
Who cannot join
- Diagnosed medical condition that prevents nutrient absorption from food (e.g. Inflammatory Bowel Disease, Celiac Disease, post-Roux-en-Y/Gastric sleeve surgery)
- Pregnant or breastfeeding
- Current antibiotic use or within past 3 months
- Current anticoagulant use or within past 3 months
- Current weight loss or fat malabsorption medication use (e.g. Glucagon-Like Peptide 1 agonists, Orlistat)
- Allergies or sensitivities to methylcellulose, vitamin D (D3, D2), or vitamin K (K2, Menaquinone-4, Menaquinone-7)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Madigan Army Medical Center
Tacoma, Washington, 98431
Mary S McCarthy, PhD, 253-968-3695, mary.s.mccarthy1.civ@health.mil
Hyojin C Yi, BSN, 253-968-2898, hyojin.c.yi.ctr@health.mil
About this study
Official title: A Double-Blind Randomized Controlled Trial Evaluating Response to Vitamin D3 and K2 Supplementation Through Inflammatory Markers and the Gut Microbiome in Healthcare Personnel
The main purpose of this research study is to learn about the effects of supplemental vitamin D3 and vitamin K2 on blood levels and the gut microbial community, called the gut microbiome. There are many influences on blood levels of vitamin D and K to include your dietary intake, lifestyle behaviors (physical activity, sleep), genetic alterations in metabolism of these vitamins, and the gut microbial abundance and diversity. You will be asked to take one capsule containing vitamin D3 (125 mcg), vitamin K2 (180 mcg), a combination of vitamins D3 and K2 (same doses as previous), or a placebo powder for 90 days. You will also be asked to complete questionnaires, undergo body composition and blood pressure measurements, provide blood samples and a stool swab, all on 2 occasions about 3 - 4 months apart. By conducting this study, we aim to identify the frequency of common genetic alterations in vitamins D and K metabolism and establish the impact on the gut microbiome for the first time. Your participation in this study will last about 4 - 6 months and include up to 3 visits.
Read the detailed description
Health promotion efforts for all branches of Service aim to ensure the health and readiness of the Force. This timely, relevant study supports this effort as well as the TriService Nursing Research Program priorities of Fit and Ready Force, Care for the Caregiver, and Translate Research into Practice. In 2023, the Defense Health Agency unveiled its strategic plan through 2028 which included these two priorities, 1) 'achieving new levels of excellence by fully leveraging emerging scientific and technological advancements to optimize the health and care experience of our beneficiaries', and 2) 'creating a workplace where people are the primary focus, and the principles of high reliability nurture and energize each individual'. The previous nutrigenomics work by this research team, the expertise and enthusiasm of our new members, and the choice of diverse cohorts for this study, presents an exciting and potentially impactful extension of nutrigenomics with metagenomics of the gut microbiome to provide insight into complex nutrient pathways and specifically, the response of the gut microbial community to select micronutrients. Vitamin D and vitamin K2 are vital micronutrients that support immune, bone, gut, and cardiometabolic health with insufficiencies contributing to musculoskeletal injuries (MSKi), metabolic syndrome, cardiovascular disease, and gut dysbiosis. This Follow-On research application advances the science linking vitamin D, lifestyle behaviors, and chronic disease prevention in healthy adults by probing unexplored areas such as a key symbiotic nutrient, vitamin K2, with vitamin D3, next generation sequencing (NGS) of polymorphisms involved in vitamin metabolism pathways as well as metagenomics to assess the response of the gut microbial community to dietary and supplemental nutrients. The Specific Aims and research questions for our study include:
Specific Aim 1. Evaluate effect of vitamin D3 and K2 dietary intake and supplementation groups vs placebo group on the gut microbiome; Research Question (RQ)1.a. Will gut microbiome composition, diversity, and richness respond differently to each treatment group - vitamin D3, vitamin K2, D3+K2 versus the control group? RQ1.b. What effect will vitamin D3 and/or K2 metabolism pathway single nucleotide polymorphisms (SNPs) have on gut microbiome response?
Specific Aim 2. Assess response to vitamin supplementation with serum 25-hydroxyvitamin D [25(OH)D] and osteocalcin levels pre and post supplement; RQ2. Will selected doses, based on clinical experience and published data, achieve designated endpoints for sufficiency; serum 25(OH)D greater than 30 ng/mL and undercarboxylated osteocalcin (ucOC) within normal limits?
Specific Aim 3. Assess the influence of vitamin D and K metabolism pathway SNPs on serum 25(OH)D and osteocalcin to determine vitamin D3, K2, and D3 + K2 supplementation efficacy; RQ3. To what extent does the presence of vitamin D and/or K metabolism pathway SNPs affect supplement efficacy when comparing treatment vs control group response measured by serum biomarkers?
Specific Aim 4. Explore relationships between diet/Dietary Inflammatory Index (DII), lifestyle behaviors (steps and sleep), body composition, metabolic and inflammatory biomarkers, SNPs, and the gut microbiome from Baseline to 3 months; RQ4.a. What factors need consideration when exploring genetic and non-genetic contributions to the gut microbiome in the treatment vs control group? RQ4.b. What role do age, gender, body mass index, inflammation status, and lipid profile play in the gut microbiome composition?
Hypothesis 1: Genotypic alterations in vitamin D3 and/or K2 metabolism pathways will influence gut microbiome composition in response to supplementation.
Hypothesis 2: Genotypic alterations in vitamin D3 and/or K2 metabolism pathways will influence serum response to supplementation.
- Conditions
- Hypovitaminosis D, Hypovitaminosis
- Being tested
- Vitamin Arm 1, Vitamin Arm 2, Vitamin Arm 3, Placebo
- Keywords
- Hypovitaminosis D, Hypovitaminosis K, Gut microbiome
- Medical subject headings
- Vitamin D Deficiency, Avitaminosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vitamin Arm 1Dietary supplement
Subject receives dietary supplement for 90 days
Vitamin Arm 2Dietary supplement
Subject receives dietary supplement for 90 days
Vitamin Arm 3Dietary supplement
Subject receives dietary supplement for 90 days
PlaceboOther
Subject receives placebo for 90 days
| Study group | Role | What they receive |
|---|---|---|
| Vitamin Arm 1 | Active comparator | Vitamin D3 125 mcg taken orally once daily for 90 days Receives: Dietary Supplement: Vitamin Arm 1 |
| Vitamin Arm 2 | Active comparator | Vitamin K2 180 mcg taken orally once daily for 90 days Receives: Dietary Supplement: Vitamin Arm 2 |
| Vitamin Arm 3 | Active comparator | Vitamin D3 125 mcg combined with vitamin K2 180 mcg taken orally once daily for 90 days Receives: Dietary Supplement: Vitamin Arm 3 |
| Placebo Arm | Placebo comparator | Inert capsule taken orally once daily for 90 days Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Gut microbiome composition
Evaluate effect of vitamin D3 and K2 dietary intake, and assigned vitamin supplementation group versus placebo group, on the gut microbiome composition
Measured: 90 days
Gut microbiome richness
Will use Operational Taxonomic Units, Simpson Index and /or Chao1 index to evaluate gut microbiome richness before and after vitamin supplementation vs placebo
Measured: 90 days
Gut microbiome diversity
Will use Operational Taxonomic Units, Simpson Index and /or Chao1 index to evaluate gut microbiome diversity before and after vitamin supplementation vs placebo
Measured: 90 days
Secondary outcomes (4)
Serum 25OHD
Response to vitamin supplementation with serum 25(OH)D level pre and post supplement
Measured: 90 days
Serum Osteocalcin level
Response to vitamin supplementation with serum osteocalcin level pre and post supplement
Measured: 90 days
Vitamin D3 and K2 metabolic pathway variants on supplementation efficacy
Examine vitamin D3 and K2 metabolism pathway single nucleotide polymorphisms for effect on serum 25(OH)D and osteocalcin levels
Measured: 90 days
Genetic and non-genetic factor contributions to gut microbiome composition
Explore relationships between diet, lifestyle behaviors (steps and sleep), body composition, metabolic and inflammatory serum biomarkers, and single nucleotide polymorphisms, and the gut microbiome
Measured: 90 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Sep 2025
- Study start27 Mar 2025
- Primary completionMar 2026 (estimated)
- Study completionMar 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (3)Papers the sponsor has linked to this study.
- Other trials for Hypovitaminosis DStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Double-blind randomized controlled trial (RCT) with 4 arms.
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 96 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Madigan Army Medical Center
- Sponsor type
- US federal agency
- Responsible party
- Principal investigator, Mary S McCarthy, Madigan Army Medical Center
- Investigators
- Mary S McCarthy, PhD, Principal investigator, Madigan AMC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07199829
- Sponsor's protocol ID
- 225015
- Other IDs
- 11207-N24-B11
- Status last verified
- Sep 2025
- First submitted
- 6 Feb 2025
- Last updated
- 30 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: A data sharing agreement has been developed and submitted to the Defense Health Agency; approval has been received.
Publications
Akimbekov NS, Digel I, Sherelkhan DK, Lutfor AB, Razzaque MS. Vitamin D and the Host-Gut Microbiome: A Brief Overview. Acta Histochem Cytochem. 2020 Jun 26;53(3):33-42. doi: 10.1267/ahc.20011. Epub 2020 Jun 16.
PubMed 32624628Levin GP, Robinson-Cohen C, de Boer IH, Houston DK, Lohman K, Liu Y, Kritchevsky SB, Cauley JA, Tanaka T, Ferrucci L, Bandinelli S, Patel KV, Hagstrom E, Michaelsson K, Melhus H, Wang T, Wolf M, Psaty BM, Siscovick D, Kestenbaum B. Genetic variants and associations of 25-hydroxyvitamin D concentrations with major clinical outcomes. JAMA. 2012 Nov 14;308(18):1898-905. doi: 10.1001/jama.2012.17304.
PubMed 23150009Ammar M, Heni S, Tira MS, Khalij Y, Hamdouni H, Amor D, Ksibi S, Omezzine A, Bouslama A. Variability in response to vitamin D supplementation according to vitamin D metabolism related gene polymorphisms in healthy adults. Eur J Clin Nutr. 2023 Feb;77(2):189-194. doi: 10.1038/s41430-022-01218-y. Epub 2022 Sep 27.
PubMed 36167979
Study at a glance
From the registry record, last updated by the sponsor on 30 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Double-Blind Randomized Controlled Trial Evaluating Response to Vitamin D3 and K2 Supplementation Through Inflammatory Markers and the Gut Microbiome in Healthcare Personnel
- ClinicalTrials.gov ID
- NCT07199829
- Acronym / sponsor ID
- 225015
- Conditions
- Hypovitaminosis D, Hypovitaminosis
- Keywords
- Hypovitaminosis D, Hypovitaminosis K, Gut microbiome
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 96 participants (estimated)
- Lead sponsor
- Madigan Army Medical CenterUS federal agency
- Study start
- 27 Mar 2025 (actual)
- Primary completion
- Mar 2026 (estimated)
- Study completion
- Mar 2026 (estimated)
- First posted
- 30 Sep 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 main purpose of this research study is to learn about the effects of supplemental vitamin D3 and vitamin K2 on blood levels and the gut microbial community, called the gut microbiome. There are many influences on blood levels of vitamin D and K to include your dietary intake, lifestyle behaviors (physical activity, sleep), genetic alterations in metabolism of these vitamins, and the gut microbial abundance and diversity. You will be asked to take one capsule containing vitamin D3 (125 mcg), vitamin K2 (180 mcg), a combination of vitamins D3 and K2 (same doses as previous), or a placebo powder for 90 days. You will also be asked to complete questionnaires, undergo body composition and blood pressure measurements, provide blood samples and a stool swab, all on 2 occasions about 3 - 4 months apart. By conducting this study, we aim to identify the frequency of common genetic alterations in vitamins D and K metabolism and establish the impact on the gut microbiome for the first time. Your participation in this study will last about 4 - 6 months and include up to 3 visits.
Detailed description
Health promotion efforts for all branches of Service aim to ensure the health and readiness of the Force. This timely, relevant study supports this effort as well as the TriService Nursing Research Program priorities of Fit and Ready Force, Care for the Caregiver, and Translate Research into Practice. In 2023, the Defense Health Agency unveiled its strategic plan through 2028 which included these two priorities, 1) 'achieving new levels of excellence by fully leveraging emerging scientific and technological advancements to optimize the health and care experience of our beneficiaries', and 2) 'creating a workplace where people are the primary focus, and the principles of high reliability nurture and energize each individual'. The previous nutrigenomics work by this research team, the expertise and enthusiasm of our new members, and the choice of diverse cohorts for this study, presents an exciting and potentially impactful extension of nutrigenomics with metagenomics of the gut microbiome to provide insight into complex nutrient pathways and specifically, the response of the gut microbial community to select micronutrients. Vitamin D and vitamin K2 are vital micronutrients that support immune, bone, gut, and cardiometabolic health with insufficiencies contributing to musculoskeletal injuries (MSKi), metabolic syndrome, cardiovascular disease, and gut dysbiosis. This Follow-On research application advances the science linking vitamin D, lifestyle behaviors, and chronic disease prevention in healthy adults by probing unexplored areas such as a key symbiotic nutrient, vitamin K2, with vitamin D3, next generation sequencing (NGS) of polymorphisms involved in vitamin metabolism pathways as well as metagenomics to assess the response of the gut microbial community to dietary and supplemental nutrients. The Specific Aims and research questions for our study include:
Specific Aim 1. Evaluate effect of vitamin D3 and K2 dietary intake and supplementation groups vs placebo group on the gut microbiome; Research Question (RQ)1.a. Will gut microbiome composition, diversity, and richness respond differently to each treatment group - vitamin D3, vitamin K2, D3+K2 versus the control group? RQ1.b. What effect will vitamin D3 and/or K2 metabolism pathway single nucleotide polymorphisms (SNPs) have on gut microbiome response?
Specific Aim 2. Assess response to vitamin supplementation with serum 25-hydroxyvitamin D [25(OH)D] and osteocalcin levels pre and post supplement; RQ2. Will selected doses, based on clinical experience and published data, achieve designated endpoints for sufficiency; serum 25(OH)D greater than 30 ng/mL and undercarboxylated osteocalcin (ucOC) within normal limits?
Specific Aim 3. Assess the influence of vitamin D and K metabolism pathway SNPs on serum 25(OH)D and osteocalcin to determine vitamin D3, K2, and D3 + K2 supplementation efficacy; RQ3. To what extent does the presence of vitamin D and/or K metabolism pathway SNPs affect supplement efficacy when comparing treatment vs control group response measured by serum biomarkers?
Specific Aim 4. Explore relationships between diet/Dietary Inflammatory Index (DII), lifestyle behaviors (steps and sleep), body composition, metabolic and inflammatory biomarkers, SNPs, and the gut microbiome from Baseline to 3 months; RQ4.a. What factors need consideration when exploring genetic and non-genetic contributions to the gut microbiome in the treatment vs control group? RQ4.b. What role do age, gender, body mass index, inflammation status, and lipid profile play in the gut microbiome composition?
Hypothesis 1: Genotypic alterations in vitamin D3 and/or K2 metabolism pathways will influence gut microbiome composition in response to supplementation.
Hypothesis 2: Genotypic alterations in vitamin D3 and/or K2 metabolism pathways will influence serum response to supplementation.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 4
- Model description
- Double-blind randomized controlled trial (RCT) with 4 arms.
| Arm | Type | Receives |
|---|---|---|
| Vitamin Arm 1 | Active comparator | Dietary Supplement: Vitamin Arm 1Vitamin D3 125 mcg taken orally once daily for 90 days |
| Vitamin Arm 2 | Active comparator | Dietary Supplement: Vitamin Arm 2Vitamin K2 180 mcg taken orally once daily for 90 days |
| Vitamin Arm 3 | Active comparator | Dietary Supplement: Vitamin Arm 3Vitamin D3 125 mcg combined with vitamin K2 180 mcg taken orally once daily for 90 days |
| Placebo Arm | Placebo comparator | Other: PlaceboInert capsule taken orally once daily for 90 days |
Who may qualify
- Ages
- 18 to 69 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- able to read and understand English
- 25 OHD serum level equal to or less than 30 ng/mL
- willing to discontinue vitamin D3 and/or K2 supplements for 4.5 months
- military beneficiary (Active Duty, Retired, Dependent)
- remaining employed at workplace for 6 months
Key exclusion criteria (6 listed)
- Diagnosed medical condition that prevents nutrient absorption from food (e.g. Inflammatory Bowel Disease, Celiac Disease, post-Roux-en-Y/Gastric sleeve surgery)
- Pregnant or breastfeeding
- Current antibiotic use or within past 3 months
- Current anticoagulant use or within past 3 months
- Current weight loss or fat malabsorption medication use (e.g. Glucagon-Like Peptide 1 agonists, Orlistat)
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 |
|---|---|---|
| Vitamin Arm 1Subject receives dietary supplement for 90 days | Dietary supplement | Vitamin Arm 1 |
| Vitamin Arm 2Subject receives dietary supplement for 90 days | Dietary supplement | Vitamin Arm 2 |
| Vitamin Arm 3Subject receives dietary supplement for 90 days | Dietary supplement | Vitamin Arm 3 |
| PlaceboSubject receives placebo for 90 days | Other | Placebo Arm |
Primary outcome
Gut microbiome composition
Time frame: 90 days
Evaluate effect of vitamin D3 and K2 dietary intake, and assigned vitamin supplementation group versus placebo group, on the gut microbiome composition
Gut microbiome richness
Time frame: 90 days
Will use Operational Taxonomic Units, Simpson Index and /or Chao1 index to evaluate gut microbiome richness before and after vitamin supplementation vs placebo
Gut microbiome diversity
Time frame: 90 days
Will use Operational Taxonomic Units, Simpson Index and /or Chao1 index to evaluate gut microbiome diversity before and after vitamin supplementation vs placebo
4 secondary outcomes
Serum 25OHD
Time frame: 90 days
Serum Osteocalcin level
Time frame: 90 days
Vitamin D3 and K2 metabolic pathway variants on supplementation efficacy
Time frame: 90 days
Genetic and non-genetic factor contributions to gut microbiome composition
Time frame: 90 days
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 30 Sep 2025.
- Background: PubMed 32624628Akimbekov NS, Digel I, Sherelkhan DK, Lutfor AB, Razzaque MS. Vitamin D and the Host-Gut Microbiome: A Brief Overview. Acta Histochem Cytochem. 2020 Jun 26;53(3):33-42. doi: 10.1267/ahc.20011. Epub 2020 Jun 16.
- Background: PubMed 23150009Levin GP, Robinson-Cohen C, de Boer IH, Houston DK, Lohman K, Liu Y, Kritchevsky SB, Cauley JA, Tanaka T, Ferrucci L, Bandinelli S, Patel KV, Hagstrom E, Michaelsson K, Melhus H, Wang T, Wolf M, Psaty BM, Siscovick D, Kestenbaum B. Genetic variants and associations of 25-hydroxyvitamin D concentrations with major clinical outcomes. JAMA. 2012 Nov 14;308(18):1898-905. doi: 10.1001/jama.2012.17304.
- Background: PubMed 36167979Ammar M, Heni S, Tira MS, Khalij Y, Hamdouni H, Amor D, Ksibi S, Omezzine A, Bouslama A. Variability in response to vitamin D supplementation according to vitamin D metabolism related gene polymorphisms in healthy adults. Eur J Clin Nutr. 2023 Feb;77(2):189-194. doi: 10.1038/s41430-022-01218-y. Epub 2022 Sep 27.
- Individual participant dataSharing planned: Yes. A data sharing agreement has been developed and submitted to the Defense Health Agency; approval has been received.
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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.
Mary S McCarthy, PhD principal investigator
Madigan AMC
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Vitamin Arm 1, Vitamin Arm 2 and Vitamin Arm 3 in people with Hypovitaminosis D and Hypovitaminosis, run by Madigan Army Medical Center at 1 site in United States.
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 5 inclusion and 6 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 30 Sep 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 United States. 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 Mary S McCarthy, PhD (253-968-3695, mary.s.mccarthy1.civ@health.mil), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Gut microbiome composition (time frame: 90 days). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07199829, which also lists 3 linked publications.
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 30 Sep 2025.