Abstract 14467: A Randomized, Open-Label, Crossover, Multicenter Study of the Antiplatelet Effects of Ticagrelor versus Clopidogrel in Hispanic Patients With Stable Coronary Artery Disease (CAD)
Introduction: Ticagrelor is a potent, reversibly binding, P2Y12 platelet inhibitor that, compared with clopidogrel, decreased the rate of myocardial infarction (MI) and vascular mortality in acute coronary syndrome and is being investigated in patients with stable CAD and peripheral artery disease. Although CAD in Hispanics is highly prevalent and the single most frequent cause of MI and death, Hispanics are generally under-represented in pharmacodynamic and randomized clinical trials. In the present study, we sought to assess the antiplatelet effects of ticagrelor compared with clopidogrel in Hispanic patients with stable CAD.
Methods: This was a multicenter, randomized, open-label, crossover study. Hispanic patients with stable CAD were randomly allocated to either ticagrelor (180 mg loading dose [LD] followed by 90 mg twice daily maintenance dose [MD] for 7-9 days) or clopidogrel (600 mg LD followed by 75mg once daily MD for 7- 9 days), and then received the alternative P2Y12 inhibitor after an intervening washout period. All patients received aspirin 75-100 mg daily. Platelet reactivity was measured with the VerifyNow P2Y12 assay, which reports results in P2Y12 reaction units (PRU).
Results: 40 patients were enrolled: mean age ± SD (63.8 ± 8.8 yr), 30% female, and 53% diabetic. At 30 minutes after the LD, on-treatment reactivity after ticagrelor (mean ± SD) was 127 ± 108 PRU compared with 270 ± 52 PRU after clopidogrel (P<0.001) (FIGURE). At 2 hours after the LD, on-treatment reactivity was 32 ± 28 PRU and 203 ± 88 PRU for ticagrelor and clopidogrel, respectively (P<0.001). At 8 hours after the last MD, on-treatment reactivity was 39 ± 37 PRU with ticagrelor compared with 180 ± 83 PRU with clopidogrel (P<0.001). No significant adverse events were noted (including bleeding) with either study drug.
Conclusions: In Hispanic patients with stable CAD on daily low dose ASA, ticagrelor provided a significantly faster onset and greater extent of platelet inhibition than clopidogrel.
- © 2013 by American Heart Association, Inc.