Eptifibatide and Abciximab Equally Effective in Primary PCI
Abstract & Commentary
By Andrew J. Boyle, MBBS, PhD, Assistant Professor of Medicine, Interventional Cardiology, University of California, San Francisco. Dr. Boyle reports no financial relationships relevant to this field of study.
Sources: Zeymer U, et al. Randomized comparison of eptifibatide versus abciximab in primary percutaneous coronary intervention in patients with acute ST-segment elevation mycardial infarction. Results of the EVA-AMI Trial. J Am Coll Cardiol 2010;56:463-469;Akerblom A, et al. Eptifibatide is noninferior to abciximab in primary percutaneous coronary intervention. results from the SCAAR (Swedish Coronary Angiography and Angioplasty Registry). J Am Coll Cardiol 2010;56:470-475
Platelet aggregation is an important pathophysiological step in the development of myocardial infarction (MI), and intensive anti-platelet therapy has become a cornerstone of therapy in patients presenting with MI. In ST-segment elevation MI (STEMI), primary percutaneous coronary intervention (pPCI) has been shown to reduce mortality, but the optimal anti-platelet strategy during pPCI continues to evolve. Adjunctive glycoprotein IIb/IIIa inhibitors improve reperfusion rates and reduce subsequent events. The 2009 ACC/AHA guidelines for management of patients with STEMI list the use of adjunctive IIb/IIIa inhibitors at the time of pPCI as a class IIa indication: abciximab with a level of evidence A, and eptifibatide with a level of evidence B. However, there had previously been no head-to-head trials comparing these agents, particularly in the current era. Two recent studies have compared eptifibatide to abciximab in primary PCI, and both found them to be substantially equivalent.
Zeymer and colleagues randomized 427 patients with STEMI to receive either eptifibatide or abciximab in addition to pPCI and standard medical therapy, including aspirin, clopidogrel, and either heparin or enoxaparin. Baseline characteristics were similar in each group, with a mean age 61 years, ~20% female, and 43% of cases involved the left anterior descending coronary artery. Procedural characteristics also were similar between groups; 95% of patients in each group underwent PCI with similar rates of direct stenting, use of drug-eluting stents, and use of adjunctive therapies, such as aspiration thrombectomy. The primary endpoint (complete ST-segment resolution) was achieved in 63% of the eptifibatide group and 56% of the abciximab group (p = NS), indicating similar rates of reperfusion. Rates of death (6.2% vs. 4.5%; p = 0.52) and target vessel revascularization (4.4% vs. 6.5%; p = 0.39) were not different between the eptifibatide and abciximab groups, respectively. However, eptifibatide resulted in lower rates of recurrent MI (0.4% vs. 3.5%; p = 0.03) at six months. Bleeding rates were similar between groups. The authors conclude that eptifibatide, as an adjunct to pPCI, is equally as effective as abciximab with respect to ST-segment resolution.
Akerblom and colleagues report from a large European registry on 11,479 patients undergoing pPCI for STEMI who received either eptifibatide (n = 2,355) or abciximab (n = 9,124). Median age was 65 years, and approximately 28% of the cohorts were female. There appeared to be differences in the baseline demographic and procedural characteristics, so the authors performed multivariable adjustments to account for these differences. After multivariable adjustment, the rates of death and myocardial infarction were no different between groups at one-year follow-up. Comparing eptifibatide to abciximab, the odds ratio [OR] for death was 0.99 (CI 0.79–1.09) and for MI the OR was 0.88 (CI 0.73–1.05), showing no difference in these outcomes. In addition, the combined endpoint of death or MI also was no different, with an OR of 0.94 (CI 0.82–1.09). The authors conclude that eptifibatide is non-inferior to abciximab in patients with STEMI undergoing pPCI with respect to death or MI over one year.
Commentary
Perhaps the best clinical trial evidence we can get is the agreement between a randomized, controlled trial and a large real-world registry. Zeymer and colleagues' randomized, controlled trial showed non-inferiority of eptifibatide compared to abciximab. However, their trial enrolled relatively low-risk patients, with only 10% of patients having a Kilip class > 1. In addition, they used a 22-hour infusion of eptifibatide, whereas we generally use 18 hours in the United States. Furthermore, clopidogrel was given more than 30 minutes prior to angiography in 52% of patients, less than 30 minutes prior in 7%, after PCI in 20%, and unknown time in 21%, but we are not told whether there were timing differences between treatment groups or whether timing influenced ST-segment resolution. It remains unknown if the benefit of IIb/IIIa inhibitors is seen in patients receiving early loading of thienopyridines. In the registry reported by Akerblom et al, the large number of patients allowed multivariable adjustment. In an all-comers registry, they demonstrated noninferiority in the hard endpoints of death and MI at one year. This is complimentary data to the reperfusion results seen in the randomized, controlled trial by Zeymer et al. However, the registry also provides no data on the timing and loading doses of thienopyridines. These studies suggest that eptifibatide and abciximab should result in similar rates of reperfusion, death, and recurrent MI in patients presenting with STEMI treated with primary PCI.
Platelet aggregation is an important pathophysiological step in the development of myocardial infarction (MI), and intensive anti-platelet therapy has become a cornerstone of therapy in patients presenting with MI.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content