Abstract 13782: Platelet Aggregation and Adenosine Levels Among Patients With Stable Chronic Coronary Artery Disease Taking Ticagrelor or Prasugrel

Abstract

Introduction: Both, ticagrelor and prasugrel are important anti-ADP drugs, being superior to clopidogrel in patients with acute coronary syndromes (ACS). Whether those drugs have different effects among patients in the long run (> 1 year) after ACS, however, is not completely understood. We therefore sought to directly compare the pharmacodynamic action of ticagrelor vs prasugrel in patients with chronic coronary artery disease (CCAD). Methods: This was a prospective, double blinded, randomized trial that compared platelet inhibition and adenosine levels with ticagrelor (180mg loading dose, followed by 90 mg BID) versus prasugrel (60mg loading dose, followed by 10 mg QD). Patient was eligible if suffered a documented episode of ACS at least 1 year before randomization, had age between 18 and 75 years, and was using aspirin 100 mg chronically. Platelet aggregation between groups was compared with the Multiplate ADP® assay, performed at baseline and after 15 days on study medication. Adenosine plasma levels were measured with high performance liquid chromatography at the same time points. Results: We randomized 87 patients (mean age 61,3 years, 83,9% with prior coronary angioplasty), being 40 allocated to ticagrelor and 47 to prasugrel. The study main results are described at Figure 1 (platelet aggregation) and Figure 2 (plasma adenosine levels). Conclusion: In stable patients after ACS, despite significant higher levels of adenosine plasma levels in the ticagrelor group, in comparison with the prasugrel group, similar levels of platelet inhibition were observed in both groups, suggesting that the role of adenosine in platelet aggregation is not an important one.