Response to Letter Regarding, “Administration of a Loading Dose Has No Additive Effect on Platelet Aggregation During the Switch From Ongoing Clopidogrel Treatment to Ticagrelor in Patients With Acute Coronary Syndrome”

We thank Dr Gurbel et al1 for their interest and their comments on our recently published Administration of a Loading Dose Has No Additive Effect on Platelet Aggregation During the Switch From Ongoing Clopidogrel Treatment to Ticagrelor in Patients With Acute Coronary Syndrome (SHIFT-OVER) study.2 The novel antiplatelet agent, ticagrelor, has several advantages over the long-standing clopidogrel, as the virtual absence of nonresponders and the more powerful platelet inhibition. As highlighted by Gurbel et al,1 clopidogrel nonresponders were excluded from our study, for multiple reasons. First, because it is known that high on-treatment platelet reactivity is associated to a higher incidence of stent thrombosis and adverse events,3 it would have been unethical to randomize those patients. In fact, we …