NCT00482794 · Duke University
Genetic Risk Factors Associated With Antiphospholipid Antibody Syndrome
(APS)
What this study is about
Antiphospholipid antibody syndrome (APS) is characterized by the presence of antiphospholipid antibodies, which are proteins in the blood that interfere with the body's ability to perform normal blood clotting.
View original scientific description
Antiphospholipid antibody syndrome (APS) is characterized by the presence of antiphospholipid antibodies, which are proteins in the blood that interfere with the body's ability to perform normal blood clotting. Clinical problems associated with antiphospholipid antibodies include an increased risk for the formation of blood clots in the lungs or deep veins of the legs, stroke, heart attack, and recurrent miscarriages. It is possible that some people with APS have a genetic predisposition for developing the syndrome. This study will use a genetic strategy to identify potential inherited risk factors for the development of APS by recruiting people with APS who have family members also affected by the syndrome or by another autoimmune disorder, such as lupus or rheumatoid arthritis.
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
- Persistent presence of an antiphospholipid antibody, as defined by one or both of the following criteria:
- Medium or high anticardiolipin antibody level in the blood on two or more occasions at least 6 weeks apart
- Presence of lupus anticoagulant in the plasma on two or more occasions at least 6 weeks apart
- Presence of clinical symptoms seen in patients with APS, including vascular thrombosis (one or more clinical episodes of arterial, venous, or small vessel thrombosis in any tissue or organ) and/or pregnancy morbidity, defined as any of the following:
- One or more unexplained deaths of a morphologically normal fetus at or beyond the 10th week of gestation, with normal fetus morphology documented by ultrasound or direct examination or the fetus
- One or more premature births of a morphologically normal baby at or before the 34th week of gestation because of severe pre-eclampsia, eclampsia, or severe placental insufficiency
- Three or more unexplained consecutive spontaneous abortions before the 10th week of gestation, with maternal anatomic or hormonal abnormalities and paternal and maternal chromosomal causes excluded
- People who have elevated antiphospholipid antibody levels but do not fully meet clinical criteria for APS, and do have affected family members, will be considered for enrollment
Exclusion criteria
- No documented presence of antiphospholipid antibody
Where
- Durham, North Carolina
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 May 29, 2026 · Source of record for eligibility and locations