Abstract 11054: Switching From Dual Antiplatelet Treatment Regimens With Aspirin Plus a P2Y 12 Inhibitor to Dual Pathway Inhibition With Low-Dose Rivaroxaban in Adjunct to Aspirin in Patients With Coronary Artery Disease: The SWAP-AC Study

Abstract

Introduction: Dual antiplatelet therapy (DAPT) and dual pathway inhibition (DPI) are potential long-term antithrombotic strategies for patients with coronary artery disease (CAD). However, patients already on DAPT are most likely to remain on the same treatment regimen rather than switching. To date, there is no data on the feasibility of switching from DAPT to DPI and the pharmacodynamic (PD) effects of such approach. Methods: SWAP-AC was a prospective, randomized, PD study conducted in 90 patients with CAD on DAPT with aspirin (81mg/qd) plus a P2Y 12 inhibitor [clopidogrel (75 mg/qd; n=30), ticagrelor (90mg/bid; n=30), or prasugrel (10mg/qd; n=30)]. Patients in each cohort were randomized to maintain DAPT or switch to DPI (aspirin 81mg/qd plus rivaroxaban 2.5mg/bid). PD assessments included VerifyNow P2Y 12 reaction units (PRU), light transmittance aggregometry (LTA) using 20 μM ADP, tissue factor (TF), and a combination of collagen + 5 μM ADP + TF (CATF, a marker of platelet-mediated global thrombogenicity), and a thrombin generation (TG) assay. Assays were performed at baseline (on DAPT) and 30 days post-randomization [trough (before maintenance dose) and peak (2 hours after maintenance dose) levels]. Results: Switching from DAPT to DPI occurred without side effects. TG was reduced with DPI. In each cohort, DAPT was associated with lower PRU levels than DPI ( Figure ); LTA following ADP stimuli showed consistent results (data not shown). LTA following CATF stimuli (primary endpoint) showed no differences between DPI and DAPT in the ticagrelor and prasugrel, but not clopidogrel, cohorts ( Figure ). There were no differences in any of the cohorts with LTA using TF. Conclusions: SWAP-AC is the first study supporting the feasibility of switching to DPI patients with CAD on different maintenance DAPT regimens. Such approach was associated with increased P2Y 12 reactivity but reduced thrombin generation with a limited impact on platelet-mediated global thrombogenicity.