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

Recruiting

• Conditions: Arterial Thrombosis; Antiphospholipid Syndrome

• Registration Number: NCT05646394
• Lead Sponsor: McMaster University

Brief Summary

The goal of this registry is to gather more information on the efficacy and safety of various antithrombotic regimens. The registry collects data on patients with antiphospholipid syndrome and an arterial event within the past 12 months, on treatment with either A) a VKA with therapeutic range, 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, C) a VKA with therapeutic range, INR 3.0-4.0, or D) with a dual antiplatelet regimen. The follow-up is 2 years.

Detailed Description

The optimal antithrombotic management of patients with antiphospholipid syndrome and arterial thrombotic events is unclear. The guidelines provide several options, mostly with vitamin K antagonist with/without an antiplatelet agent. Dual antiplatelet therapy (DAPT) was in a meta-analysis potentially effective, but included studies were few and small.

The primary aim is to compare a vitamin K antagonist (VKA), i.e. warfarin, acenocoumarol, phenprocoumon etc, with international normalized ratio 2.0-3.0 plus low-dose aspirin (75-100 mg) with DAPT - typically low-dose aspirin plus clopidogrel (75 mg daily) but other combinations will be acceptable. The registry will also include patients treated with VKA alone at standard- or high-intensity, since this is recommended and will serve as reference groups in comparison with VKA + low-dose aspirin and versus DAPT. The outcomes are (efficacy) arterial or venous thromboembolism, vascular death or (safety) major bleeding.

A secondary objective is to analyze how the cardiovascular risk factors (hypertension, hyperlipidemia, obesity, smoking, diabetes, and heart failure), venous thrombotic risk factors (previous venous thromboembolism, cancer, immobility, chronic inflammatory disease) and anti-phospholipid profile contribute to recurrent arterial thrombosis.

Study Timeline

• Study Start: 2022-07-01
• Status Verified: 2022-12
• Study First Submitted: 2022-12-05
• Study First Submitted QC: 2022-12-05
• Study First Posted: 2022-12-12
• Last Update Submitted: 2022-12-12
• Last Update Posted: 2022-12-14
• Primary Completion: 2027-07-31
• Study Completion: 2027-12-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 150

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.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Number of Participants with thromboembolism verified by diagnostic imaging, electrocardiogram or troponin rise	2 years	Composite of arterial thrombosis (stroke, myocardial infarction, peripheral arterial thrombosis or embolism), venous thromboembolism (thrombosis in any deep vein or pulmonary embolism), and vascular death.
Number of Participants with major hemorrhage fulfilling at least one of the International Society on Thrombosis and Haemostasis criteria	2 years	Major hemorrhage according to the International Society on Thrombosis and Haemostasis

Secondary Outcome Measures

Name	Time	Method
Number of Participants with vascular death verified by diagnostic imaging, electrocardiogram or troponin rise	2 years	Death due to arterial or venous thromboembolism
Number of Participants with venous thromboembolism verified by diagnostic imaging	2 years	thrombosis in any deep vein or pulmonary embolism
Number of Participants with arterial thrombosis verified by diagnostic imaging	2 years	stroke, myocardial infarction, peripheral arterial thrombosis or embolism

Trial Locations

Locations (3)

McMaster University; 🇨🇦 Hamilton, Ontario, Canada

Instituto de Investigaciones en Salud Pública, Universidad de Buenos Aires; 🇦🇷 Buenos Aires, Ciudad Autónoma De Buenos Aires, Argentina

Clinica Universitaria Reina Fabiola; 🇦🇷 Córdoba, Argentina