Registry for Antithrombotic Treatments in Patients with Antiphospholipid Syndrome

Registry on Augmented Antithrombotic Treatment Regimens for Patients With Arterial Thrombotic APS

Observational McMaster University · NCT05646394

This study is testing different blood-thinning treatments in people with antiphospholipid syndrome who had an artery problem in the last year to see which ones are safest and most effective.

Quick facts

Study typeObservational
Enrollment150 (estimated)
Ages18 Years and up
SexAll
SponsorMcMaster University Academic / other
Locations3 sites (Buenos Aires, Buenos Aires F.D. and 2 other locations)
Trial IDNCT05646394 on ClinicalTrials.gov

What this trial studies

This registry aims to collect data on the efficacy and safety of various antithrombotic regimens in patients with antiphospholipid syndrome who have experienced an arterial event within the past year. Participants will be treated with different combinations of vitamin K antagonists and antiplatelet agents, with follow-up lasting two years. The study will compare outcomes such as arterial or venous thromboembolism and major bleeding among the treatment groups. Additionally, it will analyze how cardiovascular and venous thrombotic risk factors contribute to recurrent arterial thrombosis.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 and older with confirmed antiphospholipid syndrome and a history of arterial thrombotic events.

Not a fit: Patients who are pregnant, have a high bleeding risk, or cannot comply with treatment protocols may not benefit from this study.

Why it matters

Potential benefit: If successful, this registry could help identify the most effective antithrombotic treatment strategies for patients with antiphospholipid syndrome, potentially reducing the risk of future thrombotic events.

How similar studies have performed: While there have been few studies on dual antiplatelet therapy in this context, the approach of comparing various antithrombotic regimens is novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Patients of at least 18 years of age with confirmed antiphospholipid syndrome according to Sydney criteria and with first or recurrent arterial thrombotic manifestation, including those with asymptomatic brain infarcts on diagnostic imaging.
2. Treatment with either A) a vitamin K antagonist (VKA) with therapeutic range, international normalized ratio (INR) 2.0-3.0 plus low-dose aspirin (75-100 mg daily), B) a VKA alone with therapeutic range, INR 2.0-3.0 or C) VKA with therapeutic range, INR 3.0-4.0, or D) with a dual antiplatelet regimen, if considered appropriate by the treating physician.
3. Signed informed consent obtained (in jurisdictions where required).

Exclusion Criteria:

1. Inability to follow the patient due to geographical or other reasons.
2. Patients with documented poor compliance.
3. Bleeding risk that in the opinion of the treating physician makes combination antithrombotic therapy unsafe.
4. Pregnancy or planned pregnancy.
5. Venous thrombotic event diagnosed after the last arterial event.

Where this trial is running

Buenos Aires, Buenos Aires F.D. and 2 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Antiphospholipid SyndromeArterial Thrombosisanticoagulationvitamin K antagonistantiaggregantstrokemyocardial infarctionhemorrhage
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.