No abstract

Author Contributions: Drs Mega and Sabatine had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Background-Ticagrelor is the first reversibly binding oral P2Y 12 receptor antagonist. This is the first study to compare the onset and offset of platelet inhibition (IPA) with ticagrelor using the PLATO (PLATelet inhibition and patient Outcomes) trial loading dose (180 mg) with a high loading dose (600 mg) of clopidogrel. 0001).At 24 hours after the last dose, mean IPA was 58% for ticagrelor versus 52% for clopidogrel (PϭNS). IPA for ticagrelor on day 3 after the last dose was comparable to clopidogrel at day 5; IPA on day 5 for ticagrelor was similar to clopidogrel on day 7 and did not differ from placebo (PϭNS). Conclusions-Ticagrelor achieved more rapid and greater platelet inhibition than high-loading-dose clopidogrel; this was sustained during the maintenance phase and was faster in offset after drug discontinuation. Clinical Trial Registration Information-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00528411.