Newby L K, McGuire D K
Duke Clinical Research Institute, PO Box 17969, Durham, NC 27707-7969, USA.
Curr Cardiol Rep. 2000 Sep;2(5):372-7. doi: 10.1007/s11886-000-0049-7.
Platelet aggregation plays a central role in the pathogenesis of thrombosis and the acute coronary syndromes. When given intravenously, potent selective antagonists of fibrinogen binding to the glycoprotein (GP) IIb/IIIa receptor, the final common pathway for platelet aggregation, have been effective in the treatment of acute coronary syndromes. Their benefit ceases, however, with the end of the infusion. Aspirin reduces the incidence of secondary vascular events by 25% to 30% after an acute coronary syndrome, and clopidogrel provides modest improvement over aspirin. However, both are relatively weak antiplatelet agents that each block only one of many pathways to platelet activation and surface membrane expression of the competent GP IIb/IIIa receptor. With the success of the intravenous GP IIb/IIIa antagonists in the acute setting, recent interest has focused on the potential benefit of oral GP IIb/IIIa antagonists used long-term for secondary prevention. The oral agents tested in phase III studies thus far have not performed up to expectations, however. The following paper reviews these studies and the implications of their results.
血小板聚集在血栓形成和急性冠脉综合征的发病机制中起核心作用。当静脉给予纤维蛋白原与糖蛋白（GP）IIb/IIIa受体结合的强效选择性拮抗剂时，血小板聚集的最终共同途径，已被证明对急性冠脉综合征的治疗有效。然而，随着输注结束，其益处也随之消失。阿司匹林可使急性冠脉综合征后继发性血管事件的发生率降低25%至30%，氯吡格雷比阿司匹林有适度改善。然而，两者都是相对较弱的抗血小板药物，各自仅阻断血小板激活和有功能的GP IIb/IIIa受体表面膜表达的众多途径之一。随着静脉内GP IIb/IIIa拮抗剂在急性情况下的成功应用，近期的研究兴趣集中在长期口服GP IIb/IIIa拮抗剂用于二级预防的潜在益处上。然而，迄今为止在III期研究中测试的口服药物并未达到预期效果。以下论文回顾了这些研究及其结果的意义。
