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406 Part V: Therapeutic Principles Chapter 25: Antithrombotic Therapy 407

risk of bleeding. Subsequent studies of patients undergoing percutane- benefit from vorapaxar. Atopaxar is a low-molecular-weight inhibitor of
ous coronary intervention, the Evaluation in PTCA to Improve Long- PAR-1, which has been studied in phase II trials of patients with acute
term Outcome with Abciximab GP IIb/IIIa (α β ) Blockade (EPILOG) coronary syndrome or high-risk coronary artery disease. These
139
IIb 3
133
132
study and EPISTENT trial, demonstrated efficacy in both low-risk studies showed an increase in minimal bleeding events (16.4 percent vs.
and high-risk patients without any increase in major bleeding. Abcix- 4.5 percent) but no difference in clinically significant bleeding.
imab has also been tested in patients with acute ischemic stroke, but
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