Antiphospholipid Syndrome (APS)NCT01787305
Pilot Study of Gut Commensals in Antiphospholipid Syndrome
An observational study of Antiphospholipid Syndrome (APS), run by Yale University at 1 site in United States.
Trial summary
The purpose of this study is to explore if certain commensals within the gut microbiota (the collection of all microbes that live inside the gut) correlate with autoantibodies in the autoimmune clotting disorder called antiphospholipid syndrome. Read more about this study
- Who is it for?
- Ages 18 to 70 yearsHealthy volunteers can take part
- Conditions the study is for
- Antiphospholipid Syndrome (APS)
- How many people
- 16 participants
- Where
- 1 siteUnited States
- Study dates
- Feb 2013to Jan 2017
- Phase
- Observational
- Are there results?
- None posted in the registry
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 70 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Yale New Haven Hospital and affiliated outpatient clinics Hospital for Special Surgery and affiliated outpatient clinics
Who may be able to join
- 18-70 years of age
- One of the following groups below:
- Group 1a: Persistently positive anti-β2GPI on Coumadin (n: 10) Group 1b: Persistently positive anti-β2GPI not on Coumadin (n: 10) Group 2a: Negative aPL on Coumadin (n: 10) Group 2b: Negative aPL not on Coumadin (n: 10) Persistently positive aβ2GPI will be defined as anti-β2GPI immunoglobulin G (IgG)/IgM/IgA ≥ 40 SGU/SMU at two separate time points at least 12 weeks apart.
- Negative aPL will be defined as negative Lupus anticoagulant test, aCL IgG/IgM/IgA, and anti-β2GPI IgG/IgM/IgA within 12 months of the study entry.
Who cannot join
- Any autoimmune diseases including Rheumatoid Arthritis, Spondylarthropathy, Inflammatory Muscle Disease, and Sarcoidosis
- Steroid use greater than 10 mg/d prednisone or equivalent 30 days prior to enrollment
- Any immunosuppressive drug use within 3 months prior to screening (mycophenolate mofetil, azathioprine, methotrexate, leflunomide, rituximab, cyclophosphamide, intravenous immunoglobulin, plasmapheresis).
- Ongoing chronic infection (viral, bacterial or fungal) including known HIV, Hepatitis B/C
- Acute infection receiving any antibiotics within 30 days prior to screening
- Acute thrombosis within 2 days prior to screening
Show all 17Show fewer
- Major gastrointestinal surgery less than 5 years prior to enrollment (with the exception of appendectomy)
- Any Gastrointestinal bleeding history
- Inflammatory Bowel Disease diagnosed by biopsy
- Celiac Disease diagnosed by biopsy
- Bulimia or anorexia nervosa
- Probiotics (greater than estimated 10^9 cfu or organisms per day) within 30 days prior to enrollment (with the exception of fermented beverages, milks or yogurts).
- Morbid obesity (BMI ≥ 40)
- Diabetes Mellitus Type I or II on medical therapy
- Malignancy within one year prior to screening (with the exception of non-metastatic squamous or basal cell skin carcinomas and cervical carcinoma if received curative surgical treatment)
- Known alcohol abuse
- Pregnancy
Trial locations and contacts
1 site in 1 country.
United States1 site
Yale University School of Medicine; Yale-New Haven Hospital
New Haven, Connecticut, 06511
About this study
Official title: Longitudinal Study of the Fecal Microbiome in Persistently Anti-β2 Glycoprotein-I Positive Individuals and Patients With Antiphospholipid Syndrome
The purpose of this study is to explore if certain commensals within the gut microbiota (the collection of all microbes that live inside the gut) correlate with autoantibodies in the autoimmune clotting disorder called antiphospholipid syndrome. The study hypothesis is that particular commensals induce the autoantibodies (immune molecules that bind to self structures) and thus correlate with the level of immune cells and antibodies that are self-reactive. Participants are patients with antiphospholipid syndrome and individuals who have tested positive on a prior blood test for anti-beta2-glycoprotein I antibodies or those that have tested negative for antiphospholipid antibodies in their blood, but had a clotting event or a health problem that puts them at risk to form blood clots.
Read the detailed description
Antiphospholipid syndrome (APS) is an autoimmune disorder in which people are at risk to form blood clots. Having a positive antiphospholipid antibody (aPL) test does not mean the person has APS; but a small number of people do develop APS. These antibodies can also occur in otherwise healthy people. We believe certain bacteria in the gut may cause these antibodies to be produced.
Current treatments in APS target the blood clotting system and the goal is to prevent future blood clots. Many patients require this therapy for their entire life. If an persistent trigger can be found within the gut microbiota, it may help in developing other treatments. This study is being conducted at two centers, Yale University School of Medicine in New Haven, CT, and The Hospital for Special Surgery in Manhattan, New York. We expect to enroll a total of 40 subjects in this study at these study sites.
Visits will be as follows:
Visit 1: Initial screening visit: Review of medical records and questionnaire completion.
Visit 2 (one month after initial visit) \& Visit 3 (2 months after initial visit): Questionnaire relating to any changes that may have taken place since recruitment. Brief physical examination by the study doctor.
Overall participation: Over a period of 8 weeks.
Sample Collection:
At each study visit, a sample of blood will be obtained (approximately 6.5 tablespoons of whole blood) via one needle stick.
A take-home stool sample collection kit will be provided. Stool samples will be obtained within 24 hours before or after blood collection and delivered (or mailed) to a study site. 2 kits will be provided at the initial visit, 1 kit will be provided at the follow up visit at month 1.
- Conditions
- Antiphospholipid Syndrome (APS)
- Keywords
- microbiome, commensals, autoantibodies, autoreactive T cells
- Medical subject headings
- Antiphospholipid Syndrome
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in autoantibody levels
Certain gut bacteria will correlate with anti-β2GPI autoantibody titers in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects
Measured: Baseline
Change in autoantibody levels
Certain gut bacteria will correlate with anti-β2GPI autoantibody titers in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects
Measured: 4 weeks
Change in autoantibody levels
Certain gut bacteria will correlate with anti-β2GPI autoantibody titers in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects
Measured: 8 weeks
Secondary outcomes (3)
Change in autoreactive T cell frequencies
Certain gut bacteria will correlate with β2GPI-reactive CD4+ T-cells in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects.
Measured: Baseline
Change in autoreactive T cell frequencies
Certain gut bacteria will correlate with β2GPI-reactive CD4+ T-cells in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects.
Measured: 4 weeks
Change in autoreactive T cell frequencies
Certain gut bacteria will correlate with β2GPI-reactive CD4+ T-cells in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects.
Measured: 8 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Feb 2013 (estimated)
- Study startFeb 2013
- Primary completionJan 2017
- Study completionJan 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Antiphospholipid Syndrome (APS)Studies of the same condition, open and under way.
- More trials run by Yale UniversityThe sponsor's other registered studies.
- 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
- Observational
- Observational model
- Case-control
- Time perspective
- Other
- Enrolment
- 16 participants (actual)
Sponsor and investigators
- Lead sponsor
- Yale University
- Sponsor type
- University, hospital or other
- Collaborators
- Hospital for Special Surgery, New York, National Institute of Allergy and Infectious Diseases (NIAID)
- Responsible party
- Sponsor
- Investigators
- Martin A Kriegel, MD PhD, Principal investigator, Yale University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01787305
- Sponsor's protocol ID
- 1210010962
- Other IDs
- U01AI101990, R01AI118855-01
- Status last verified
- Sep 2026
- First submitted
- 3 Feb 2013
- Last updated
- 15 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
Publications
Ruff WE, Greiling TM, Kriegel MA. Host-microbiota interactions in immune-mediated diseases. Nat Rev Microbiol. 2020 Sep;18(9):521-538. doi: 10.1038/s41579-020-0367-2. Epub 2020 May 26.
PubMed 32457482Ruff WE, Dehner C, Kim WJ, Pagovich O, Aguiar CL, Yu AT, Roth AS, Vieira SM, Kriegel C, Adeniyi O, Mulla MJ, Abrahams VM, Kwok WW, Nussinov R, Erkan D, Goodman AL, Kriegel MA. Pathogenic Autoreactive T and B Cells Cross-React with Mimotopes Expressed by a Common Human Gut Commensal to Trigger Autoimmunity. Cell Host Microbe. 2019 Jul 10;26(1):100-113.e8. doi: 10.1016/j.chom.2019.05.003. Epub 2019 Jun 18.
PubMed 31227334
Study at a glance
From the registry record, last updated by the sponsor on 15 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Longitudinal Study of the Fecal Microbiome in Persistently Anti-β2 Glycoprotein-I Positive Individuals and Patients With Antiphospholipid Syndrome
- ClinicalTrials.gov ID
- NCT01787305
- Acronym / sponsor ID
- 1210010962
- Conditions
- Antiphospholipid Syndrome (APS)
- Keywords
- microbiome, commensals, autoantibodies, autoreactive T cells
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 16 participants (actual)
- Lead sponsor
- Yale UniversityUniversity, hospital or other
- Collaborators
- Hospital for Special Surgery, New York, National Institute of Allergy and Infectious Diseases (NIAID)
- Study start
- Feb 2013 (actual)
- Primary completion
- Jan 2017 (actual)
- Study completion
- Jan 2017 (actual)
- First posted
- 8 Feb 2013 (estimated)
- 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 purpose of this study is to explore if certain commensals within the gut microbiota (the collection of all microbes that live inside the gut) correlate with autoantibodies in the autoimmune clotting disorder called antiphospholipid syndrome. The study hypothesis is that particular commensals induce the autoantibodies (immune molecules that bind to self structures) and thus correlate with the level of immune cells and antibodies that are self-reactive. Participants are patients with antiphospholipid syndrome and individuals who have tested positive on a prior blood test for anti-beta2-glycoprotein I antibodies or those that have tested negative for antiphospholipid antibodies in their blood, but had a clotting event or a health problem that puts them at risk to form blood clots.
Detailed description
Antiphospholipid syndrome (APS) is an autoimmune disorder in which people are at risk to form blood clots. Having a positive antiphospholipid antibody (aPL) test does not mean the person has APS; but a small number of people do develop APS. These antibodies can also occur in otherwise healthy people. We believe certain bacteria in the gut may cause these antibodies to be produced.
Current treatments in APS target the blood clotting system and the goal is to prevent future blood clots. Many patients require this therapy for their entire life. If an persistent trigger can be found within the gut microbiota, it may help in developing other treatments. This study is being conducted at two centers, Yale University School of Medicine in New Haven, CT, and The Hospital for Special Surgery in Manhattan, New York. We expect to enroll a total of 40 subjects in this study at these study sites.
Visits will be as follows:
Visit 1: Initial screening visit: Review of medical records and questionnaire completion.
Visit 2 (one month after initial visit) \& Visit 3 (2 months after initial visit): Questionnaire relating to any changes that may have taken place since recruitment. Brief physical examination by the study doctor.
Overall participation: Over a period of 8 weeks.
Sample Collection:
At each study visit, a sample of blood will be obtained (approximately 6.5 tablespoons of whole blood) via one needle stick.
A take-home stool sample collection kit will be provided. Stool samples will be obtained within 24 hours before or after blood collection and delivered (or mailed) to a study site. 2 kits will be provided at the initial visit, 1 kit will be provided at the follow up visit at month 1.
Study design
- Observational model
- Case-control
- Time perspective
- Other
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Yale New Haven Hospital and affiliated outpatient clinics Hospital for Special Surgery and affiliated outpatient clinics
Key inclusion criteria (4 listed)
- 18-70 years of age
- One of the following groups below:
- Group 1a: Persistently positive anti-β2GPI on Coumadin (n: 10) Group 1b: Persistently positive anti-β2GPI not on Coumadin (n: 10) Group 2a: Negative aPL on Coumadin (n: 10) Group 2b: Negative aPL not on Coumadin (n: 10) Persistently positive aβ2GPI will be defined as anti-β2GPI immunoglobulin G (IgG)/IgM/IgA ≥ 40 SGU/SMU at two separate time points at least 12 weeks apart.
- Negative aPL will be defined as negative Lupus anticoagulant test, aCL IgG/IgM/IgA, and anti-β2GPI IgG/IgM/IgA within 12 months of the study entry.
Key exclusion criteria (17 listed)
- Any autoimmune diseases including Rheumatoid Arthritis, Spondylarthropathy, Inflammatory Muscle Disease, and Sarcoidosis
- Steroid use greater than 10 mg/d prednisone or equivalent 30 days prior to enrollment
- Any immunosuppressive drug use within 3 months prior to screening (mycophenolate mofetil, azathioprine, methotrexate, leflunomide, rituximab, cyclophosphamide, intravenous immunoglobulin, plasmapheresis).
- Ongoing chronic infection (viral, bacterial or fungal) including known HIV, Hepatitis B/C
- Acute infection receiving any antibiotics within 30 days prior to screening
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Change in autoantibody levels
Time frame: Baseline
Certain gut bacteria will correlate with anti-β2GPI autoantibody titers in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects
Change in autoantibody levels
Time frame: 4 weeks
Certain gut bacteria will correlate with anti-β2GPI autoantibody titers in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects
Change in autoantibody levels
Time frame: 8 weeks
Certain gut bacteria will correlate with anti-β2GPI autoantibody titers in anti-β2GPI-positive subjects that are lower or absent in aPL-negative subjects
3 secondary outcomes
Change in autoreactive T cell frequencies
Time frame: Baseline
Change in autoreactive T cell frequencies
Time frame: 4 weeks
Change in autoreactive T cell frequencies
Time frame: 8 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Sep 2026.
- Background: PubMed 32457482Ruff WE, Greiling TM, Kriegel MA. Host-microbiota interactions in immune-mediated diseases. Nat Rev Microbiol. 2020 Sep;18(9):521-538. doi: 10.1038/s41579-020-0367-2. Epub 2020 May 26.
- Results publication: PubMed 31227334Ruff WE, Dehner C, Kim WJ, Pagovich O, Aguiar CL, Yu AT, Roth AS, Vieira SM, Kriegel C, Adeniyi O, Mulla MJ, Abrahams VM, Kwok WW, Nussinov R, Erkan D, Goodman AL, Kriegel MA. Pathogenic Autoreactive T and B Cells Cross-React with Mimotopes Expressed by a Common Human Gut Commensal to Trigger Autoimmunity. Cell Host Microbe. 2019 Jul 10;26(1):100-113.e8. doi: 10.1016/j.chom.2019.05.003. Epub 2019 Jun 18.
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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. This study is not recruiting at the moment.
Martin A Kriegel, MD PhD principal investigator
Yale University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Antiphospholipid Syndrome (APS), run by Yale University 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 4 inclusion and 17 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: finished, as of the sponsor's last update on 15 Sep 2026. 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. 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in autoantibody levels (time frame: Baseline). 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 NCT01787305, which also lists 2 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 15 Sep 2026.