The acute ischemic coronary syndromes of unstable angina and non-Q-wave myocardial infarction are most commonly caused by intracoronary thrombosis at the site of ruptured atherosclerotic plaque. The main goals of therapy are the relief of ischemia and prevention of life-threatening thrombotic events. Current antithrombotic management includes heparin and aspirin, but recent insights into the pathophysiology of these syndromes have revealed that more effective management may be achieved by direct inhibition of the final common pathway to platelet aggregation--the platelet glycoprotein (GP) IIb-IIIa receptor. Earlier studies of the reversible peptide inhibitor of the GP IIb-IIIa receptor, eptifibatide (INTEGRILIN), in patients with unstable angina have demonstrated its potential in reducing acute ischemic events. The Platelet Glycoprotein IIb-IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial, the largest clinical trial of any GP IIb-IIIa receptor inhibitor to date, is a recently completed phase III evaluation of eptifibatide as primary management for patients with acute coronary syndromes presenting without persistent ST-segment elevation.