NCT07645755Not yet recruiting
CRETA (Clopidogrel Responsiveness in Essential ThrombocithemiA)
Evaluation of Response to Clopidogrel in Patients With Essential Thrombocythemia
Source: ClinicalTrials.gov · Last updated 12 Jun 2026
Brief summary (registry, in English)
Essential thrombocythemia (ET) is a chronic myeloproliferative neoplasm associated with increased platelet production and activation, leading to a high risk of thrombotic complications. Low-dose aspirin is the standard antiplatelet therapy for thrombosis prevention; however, the accelerated platelet turnover characteristic of ET results in rapid recovery of platelet function, making once-daily aspirin insufficient in many patients. Consequently, twice-daily low-dose aspirin is currently recommended to achieve adequate and sustained platelet inhibition. For patients intolerant to aspirin, clopidogrel 75 mg/day is the approved alternative. Clopidogrel irreversibly inhibits the platelet P2Y12 receptor, but its pharmacodynamic effect is highly variable because it is a prodrug requiring metabolic activation. Studies in non-ET populations have shown that higher clopidogrel doses (150 mg/day) provide stronger and more consistent platelet inhibition without significantly increasing bleeding risk. Evidence on clopidogrel use in ET is limited, but available data suggest that standard-dose therapy may result in inadequate platelet inhibition, potentially reducing antithrombotic efficacy. Platelet function testing can identify patients with high residual platelet reactivity ("poor responders"), who may benefit from dose escalation. Therefore, in ET patients requiring clopidogrel therapy, assessment of platelet responsiveness may help optimize treatment, ensuring adequate platelet inhibition and potentially improving protection against thrombotic events.
- Status (registry)
- Not yet recruiting
- Study type
- Observational
- Enrollment
- 50 (estimated)
- First submitted
- 9 Jun 2026
- Start date
- Jul 2026
- Primary completion date
- Jul 2027
- Lead sponsor
- Fondazione Policlinico Universitario Agostino Gemelli IRCCS
- Diseases
- Myeloproliferative neoplasms
- NCT number
- NCT07645755
What you commit to
- Study type: Observational
- Planned participants: 50
- From Jul 2026 to the primary completion date, Jul 2027
- 2 sites in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Need for anticoagulant therapy;
- Concomitant use of other antiplatelet agents;
- Chronic use of non-steroidal anti-inflammatory drugs (NSAIDs) (i.e \> 3 days per week);
- Chronic corticosteroid therapy exceeding a daily dose equivalent to prednisone 5 mg
Lab values
- Platelet count \>1,000,000/μL on three separate determinations within the 2 months prior to enrollment;
Who the study is looking for
- Male or female subjects age ≥ 18 years;
- Confirmed diagnosis of ET according to the 2022 WHO classification criteria30;
- Patients treated with clopidogrel 75 mg od as antithrombotic prophylaxis since at least 3 weeks, as per the indication of the referring hematologist;
- Ability to understand the nature of the study and voluntarily provide written informed consent patients whose responsiveness to the standard clopidogrel regimen was determined, based on clinical practice, using the VN-P2Y12 method.
Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers
Sites (2)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Azienda USL di Pescara - Ospedale Santo Spirito Coordinator of this site? Confirm its status | Pescara | Italy | Unknown status |
| AOU Città della Salute e della Scienza di Torino Coordinator of this site? Confirm its status | Torino | Italy | Unknown status |
This page is information, not medical advice. Discuss any trial with your doctor.