Evaluation of Platelet Aggregability in Patients with Takayasu's Arteritis

Active, not recruiting

• Conditions: Takayasu Arteritis (TAK); Vasculitis, Systemic
• Interventions: Drug: Clopidogrel

• Registration Number: NCT06807788
• Lead Sponsor: Jose Carlos Nicolau

Brief Summary

Inflammatory syndromes in general, and primary vasculitis specifically, present a high risk of cardiovascular involvement. Takayasu arteritis (TAK), for example, presents cardiovascular complications in up to 60% of cases. It is a systemic inflammatory disease that primarily affects large vessels, such as the aorta and its main branches. From a pathophysiological point of view, there are several causes that can lead to an exacerbated increase in cardiovascular risk in this population, including accelerated atherosclerosis, pro-inflammatory action of platelets and significant endothelial dysfunction.

In this context, the present case-control study intends to include 100 individuals (50 with TAK - case group, and 50 healthy volunteers - control group), matched by age and sex in a 1:1 ratio. The main objective of the study is to compare platelet aggregability in patients with TAK against healthy volunteers using the AggRAM® test. Among its secondary objectives is the analysis of platelet aggregability by other methods (Plateletworks, Chronolog, and PPAnalysis).

The study aims to significantly contribute to a better understanding of the potential influence of TAK on platelet aggregation and the response to antiplatelet agents, thereby contributing to a better understanding of the disease, with evident prognostic and therapeutic implications.

Detailed Description

Not available

Study Timeline

• Study Start: 2024-10-14
• Status Verified: 2025-01
• Study First Submitted: 2025-01-29
• Study First Submitted QC: 2025-01-29
• Last Update Submitted: 2025-01-29
• Study First Posted: 2025-02-04
• Last Update Posted: 2025-02-04
• Primary Completion: 2026-10-14
• Study Completion: 2027-10-14

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

• Patients with TAK, according to the ACR/EULAR 2022 classification criteria (score ≥ 5 out of a total of 20 points) [17]
• Age > 18 years
• Using acetylsalicylic acid
• Agreement to sign the Free and Informed Consent Form (TCLE).

Exclusion Criteria

• Previous hemorrhagic stroke

  • Use of another antiplatelet agent other than acetylsalicylic acid
  • Active infection or current use of systemic antimicrobial therapy
  • Known platelet dysfunction or platelets <150,000/µL or >450,000/µL
  • Severe illness with life expectancy ≤12 months
  • Known liver disease or coagulation disorder
  • Abuse of illicit drugs or alcohol
  • Dementia, psychiatric condition or any condition that, in the researcher's opinion, prevents participation and follow-up in the protocol

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Takayasu Arteritis Case Group	Clopidogrel	50 patients with Takayasu arteritis
Healthy Volunteers Control Group	Clopidogrel	50 healthy volunteers

Primary Outcome Measures

Name	Time	Method
Platelet Aggregation analyzed by optical aggregometry-ADP (AggRAM™- Helena Laboratories)	14 days	Compare platelet aggregation analyzed by optical aggregometry-ADP (AggRAM™- Helena Laboratórios) between both groups

Secondary Outcome Measures

Name	Time	Method
Platelet aggregability by AggRAM™ arachidonic acid at baseline;	Baseline	Avaliation of Platelet aggregability by AggRAM™ arachidonic acid at baseline
Platelet aggregability by AggRAM™ ADP after 14 days of use of Clopidogrel 75 mg/day;	14 days	Evaluation of Platelet aggregability by AggRAM™ ADP after 14 days of use of Clopidogrel 75 mg/day;
Platelet aggregability by Plateletworks-ADP at baseline and after 14 days of use of Clopidogrel 75 mg/day	14 days	Evaluation of Platelet aggregability by Plateletworks-ADP at baseline and after 14 days of use of Clopidogrel 75 mg/day;
Serum levels of ultrasensitive C-reactive protein (hs-CRP);	Baseline	Avaliation of Serum levels of ultrasensitive C-reactive protein (hs-CRP)
Serum levels of immature platelets;	Baseline	Evaluation of Serum levels of immature platelets
Platelet count	Baseline	Evaluation of Platelet count;
Serum levels of P-Selectin	Baseline	Evaluation of Serum levels of P-Selectin
Serum levels of interleukin 6	Baseline	Evaluation of Serum levels of interleukin 6;
Serum levels of Interleukin 1	Baseline	Evaluation of interleukin 1
Serum levels of cholesterol ester transfer proteins;	Baseline	Evaluation of Serum levels of cholesterol ester transfer proteins;
Serum levels of Lipoprotein(a) (LPa)	Baseline	Evaluation of Serum levels of Lipoprotein(a) (LPa)

Trial Locations

Locations (1)

Heart Institute (InCor) / University of São Paulo, São Paulo; 🇧🇷 São paulo, Brazil