Mechanistic Study of Anti-Platelet Therapy in Atherosclerosis

NCT ID: NCT07169513

Last Updated: 2025-09-11

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 60 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-10-01
• Study Completion Date: 2026-07-01

Brief Summary

Many people have a higher chance of getting heart problems. These individuals include people who are very overweight (obesity), have high blood pressure (hypertension), diabetes, or other health concerns. Heart problems often happen because of a condition called atherosclerosis. This condition is when the arteries, which are the blood vessels carrying blood from the heart, become hard and inflamed (swollen and irritated) at the same time. Atherosclerosis causes arteries narrowing, making it harder for blood to flow through. The signs of atherosclerosis can be mild, like feeling chest pain (called angina) because the heart isn't getting enough blood. In more serious cases, it can lead to a heart attack.

Think of inflammation as the body's natural alarm system. When a person gets hurt or sick, the body releases special chemicals. These chemicals tell the immune system (the body's defence team) to come and help. Their job is to heal the injury or fight off the infection.

While inflammation is usually good, sometimes it can go wrong. Atherosclerosis is one of these conditions where the inflammation in the blood vessels becomes abnormal. This ongoing inflammation can harm the body and lead to various heart problems and other health issues not directly related to the heart.

In atherosclerosis, platelets (cell fragments in our blood that form clots and stop or prevent bleeding) bind to monocytes (a type of white blood cell and a type of phagocyte - part of the immune system) to form clusters called monocyte platelet aggregate (MPA). Studies have shown that people with atherosclerosis have higher levels of the monocytes clustering with the platelets. This aggregate contributes to the worsening of atherosclerosis. Additionally, this aggregate can predict the risk of developing various cardiac diseases.

Anti-platelet (anti-clotting) medications work by stopping platelet function. In this study, investigators are giving participants two different anti-platelet medications to study the effect of these medications on the level of MPA. The target people of our study are the people with silent atherosclerosis (there is an accumulation of lipids in the blood vessels but no signs or symptoms). No existing research demonstrates whether the two most commonly prescribed anti-platelets (aspirin and clopidogrel) can help reduce MPA levels. This study aims to show the effect of anti-platelet medications on the level of MPA and other inflammatory indicators. The two medications are aspirin and clopidogrel. These two drugs are already available in the market and widely used by different patients for different reasons. Aspirin and clopidogrel have different modes of action to stop platelet function.

Conditions

Peripheral Arterial Disease; Silent Atherosclerosis

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: SINGLE

Study Groups

Aspirin/Clopidogrel

Group Type: ACTIVE_COMPARATOR

Aspirin 75 mg daily

Intervention Type: DRUG

For group 1 patients

Clopidogrel 75 mg daily

Intervention Type: DRUG

For group 2 patients

Clopidogrel/DAPT

Group Type: ACTIVE_COMPARATOR

Clopidgrel 75 mg daily

Intervention Type: DRUG

For group 1 patients

Aspirin 75 mg daily + Clopidgrel 75 mg daily

Intervention Type: DRUG

For group 2 patients

Interventions

Aspirin 75 mg daily

For group 1 patients

Intervention Type: DRUG

Clopidogrel 75 mg daily

For group 2 patients

Intervention Type: DRUG

Clopidgrel 75 mg daily

For group 1 patients

Intervention Type: DRUG

Aspirin 75 mg daily + Clopidgrel 75 mg daily

For group 2 patients

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

Group 1:

• Male or female age 18 years or older
• Willing to participate in the study, and able to give informed consent
• Negative pregnancy test for a childbearing age woman
• Receiving standard of care
• Confirmed atherosclerotic cardiovascular risk based on clinical assessment

Group 2:

• Male or female age 18 years or older
• Willing to participate in the study, and able to give informed consent
• Receiving standard of care
• Negative pregnancy test for a childbearing age woman
• Confirmed diagnosis of peripheral arterial disease (ankle-brachial index below 0.9) with Rutherford grade 1-3.

Exclusion Criteria

Group 1:

• Diabetes
• Receiving any anti-platelet medications within the last two weeks
• Receiving any anticoagulant medications within the last two weeks
• Receiving statin medications within the last two weeks
• Known major organ dysfunction
• Significant co-morbidities
• Pregnancy or lactating woman
• Unwilling, or unable to give informed consent
• Presence of co-existing autoimmune disease
• Hypersensitivity to aspirin or clopidogrel
• Severe hepatic impairment (Child-Pugh grade C)
• Active peptic ulcer
• Presence of co-existing inflammatory or autoimmune diseases
• Frequent use of medications known to affect platelet function five days before baseline phlebotomy and during the study

• Non-steroidal anti-inflammatory drugs (NSAIDs)
• Antihistamines
• Selective serotonin reuptake inhibitors
• Platelet count < 100 × 109 /L or > 450 × 109 /L
• Anaemia
• Any known bleeding diathesis
• Currently involved in other clinical research studies

Group 2:

• Diabetes
• Patients with PAD Rutherford category of more than 3
• Receiving any anticoagulant medications within the last two weeks
• Known major organ dysfunction
• Pregnancy or lactating woman
• Unwilling, or unable, to give informed consent
• Hypersensitivity to aspirin or clopidogrel
• Severe hepatic impairment (Child-Pugh grade C)
• Active peptic ulcer
• Presence of co-existing autoimmune disease
• Frequent use of medications known to affect platelet function five days before baseline phlebotomy and during the study

• Non-steroidal anti-inflammatory drugs (NSAIDs)
• Antihistamines
• Selective serotonin reuptake inhibitors
• Platelet count < 100 × 109 /L or > 450 × 109 /L
• Anaemia
• Any known bleeding diathesis
• Currently involved in other clinical research studies

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

King's College London

OTHER

Sponsor Role: collaborator

Guy's and St Thomas' NHS Foundation Trust

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Guy's and St Thomas' NHS Foundation Trust

London, , United Kingdom

Countries

United Kingdom

Central Contacts

Ashish Patel

Role: CONTACT

ashish.patel@kcl.ac.uk

0442071880216

Eman Al Musalami

Role: CONTACT

eman.1.al_musalami@kcl.ac.uk

Facility Contacts

Ashish Patel

Role: primary

ashish.patel@kcl.ac.uk

0442071880216

Eman Al Musalami

Role: backup

eman.1.al_musalami@kcl.ac.uk

Other Identifiers

174661

Identifier Type: -

Identifier Source: org_study_id