Reversibility of Dual Antiplatelet Therapy by Platelets
Reversibility of Dual Antiplatelet Therapy by Platelets.Phase II Study
Aperçu de l'étude
Statut
Les conditions
Description détaillée
Dual antiplatelet therapy with aspirin and clopidogrel is a well established strategy to prevent thrombotic complications in patients with high platelet reactivity following plaque rupture in acute coronary syndromes (ACS) or percutaneous coronary interventions. Current practice guidelines for antiplatelet therapy advocate a one to 12 months dual antiplatelet therapy after bare metal stent PCI and a 12 months dual antiplatelet therapy after PCI in patients with ACS and drug eluting stent PCI. Although oral antiplatelet therapy is associated with both, short- as well as long-term clinical efficacy, irreversible platelet inhibition carries a substantial risk of bleeding particularly in patients presenting for surgery. Empiric therapy of bleeding consists of platelet transfusion. However, there are currently no pharmacodynamic studies assessing the effect of stored platelets on in-vitro platelet function tests.
Healthy volunteers will donate platelets, take aspirin and clopidogrel for 3 days (loading dose aspirin 300 mg, clopidogrel 300 mg, maintenance dose aspirin 100 mg, clopidogrel 75 mg) and platelets will be retransfused on the 4th day. Pharmacodynamic measurements of platelet function will be performed at baseline, after drug intake before retransfusion, immediately after retransfusion and 24 hours thereafter.
Type d'étude
Inscription (Réel)
Phase
- Phase 2
Contacts et emplacements
Lieux d'étude
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Graz, L'Autriche, 8036
- Department of anesthesia and intensive care medicine, Medical Univerity of Graz
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Critères de participation
Critère d'éligibilité
Âges éligibles pour étudier
Accepte les volontaires sains
Sexes éligibles pour l'étude
La description
Inclusion Criteria:
- Informed consent
- Healthy volunteers, male or female (after exclusion of pregnancy if they are on birth control pill or have a contraceptive coil implanted)
- Age of consent
- Weight: 70 kg - 100 kg
- Platelet count 240 000 to 440 000/µL
- Hematocrit > 40%
- readiness to refrain from any activities prone to injury during the study period.
Exclusion criteria:
- Allergy against aspirin or clopidogrel
- History of bleeding
- History of peptic ulcer
- Intake of aspirin or NSAR during the last ten days before screening
- Gastrointestinal disease precluding resorption of aspirin and clopidogrel
- Scheduled surgery
- Any current medication
- History of hepatic disease
- 20µm ADP induced aggregation < 60% at screening
- CYP2C19 polymorphisms
- Donation of blood within the preceding 4 weeks
- Neurotic disease
- Current smoking
- Drug addiction
- Intake of grapefruits during the last 10 days before
Plan d'étude
Comment l'étude est-elle conçue ?
Détails de conception
- Objectif principal: Traitement
- Répartition: Non randomisé
- Modèle interventionnel: Affectation à un seul groupe
- Masquage: Aucun (étiquette ouverte)
Armes et Interventions
Groupe de participants / Bras |
Intervention / Traitement |
|---|---|
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Expérimental: autologous stored platelets
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Administration of autologous stored platelets
administration of autologous stored platelets
transfusion of autologous stored platelets
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Que mesure l'étude ?
Principaux critères de jugement
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
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Pharmacodynamic assessment of platelet function as assessed by 5 and 20 micromolar ADP
Délai: 7 days
|
pharmacodynamic measurements of platelet function will be assessed at baseline, after 3 days administration of aspirin and clopidogrel (300 mg loading with aspirin and clopidogrel, maintenance with 100 mg aspirin and 75 mg clopidogrel, respectively) after retransfusion of stored platelets and 24 hours thereafter
|
7 days
|
Mesures de résultats secondaires
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
|
Pharmacodynamic assessment of platelet function as assessed by 20 mM arachidonic acid
Délai: 7 days
|
pharmacodynamic measurements of platelet function will be assessed at baseline, after 3 days administration of aspirin and clopidogrel (300 mg loading with aspirin and clopidogrel, maintenance with 100 mg aspirin and 75 mg clopidogrel, respectively) after retransfusion of stored platelets and 24 hours thereafter
|
7 days
|
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Pharmacodynamic assessment of platelet function as assessed by Vasodilator stimulated phosphoprotein (VASP) phosphorylation (platelet reactivity index; PRI)
Délai: 7 days
|
pharmacodynamic measurements of platelet function will be assessed at baseline, after 3 days administration of aspirin and clopidogrel (300 mg loading with aspirin and clopidogrel, maintenance with 100 mg aspirin and 75 mg clopidogrel, respectively) after retransfusion of stored platelets and 24 hours thereafter
|
7 days
|
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Pharmacodynamic assessment of platelet function as assessed by expression of GP IIb/IIIa receptors and P-selectin (Mean fluorescence intensity %)
Délai: 7 days
|
pharmacodynamic measurements of platelet function will be assessed at baseline, after 3 days administration of aspirin and clopidogrel (300 mg loading with aspirin and clopidogrel, maintenance with 100 mg aspirin and 75 mg clopidogrel, respectively) after retransfusion of stored platelets and 24 hours thereafter
|
7 days
|
Collaborateurs et enquêteurs
Parrainer
Les enquêteurs
- Chercheur principal: Mahla Elisabeth, MD, Dept. of Anesthesia and Intensive Care Medicine, Medical University of Graz
Publications et liens utiles
Dates d'enregistrement des études
Dates principales de l'étude
Début de l'étude
Achèvement primaire (Réel)
Achèvement de l'étude (Réel)
Dates d'inscription aux études
Première soumission
Première soumission répondant aux critères de contrôle qualité
Première publication (Estimation)
Mises à jour des dossiers d'étude
Dernière mise à jour publiée (Estimation)
Dernière mise à jour soumise répondant aux critères de contrôle qualité
Dernière vérification
Plus d'information
Termes liés à cette étude
Autres numéros d'identification d'étude
- PAC_2009
- 2009-018108-17 (Numéro EudraCT)
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