Efficacy and safety of fondaparinux versus enoxaparin in patients with acute coronary syndromes treated with glycoprotein IIb/IIIa inhibitors or thienopyridines: results from the OASIS 5 (Fifth Organization to Assess Strategies in Ischemic Syndromes) trial.

Abstract

OBJECTIVES:

This study sought to evaluate the relative safety and efficacy of fondaparinux and enoxaparin in patients with acute coronary syndromes (ACS) treated with glycoprotein (GP) IIb/IIIa inhibitors or thienopyridines.

BACKGROUND:

The OASIS 5 (Fifth Organization to Assess Strategies in Ischemic Syndromes) trial showed that fondaparinux reduced major bleeding by 50% compared with enoxaparin while preserving similar efficacy. Whether this benefit is consistent in the presence or absence of concurrent antiplatelet therapy with clopidogrel and GP IIb/IIIa inhibitors is unknown.

METHODS:

Patients with ACS (n = 20,078) were randomized as a part of the OASIS 5 trial to receive either fondaparinux or enoxaparin. The use of GP IIb/IIIa inhibitors or thienopyridines was at the discretion of the treating physician. A Cox proportional hazard model was used to compare outcomes.

RESULTS:

Of the 20,078 patients randomized, 3,630 patients received GP IIb/IIIa and 13,531 received thienopyridines. There was a 40% reduction in major bleeding with fondaparinux compared with enoxaparin in those treated with GP IIb/IIIa (5.2% vs. 8.3%, hazard ratio [HR]: 0.61, p < 0.001). A similar reduction was found in those treated with thienopyridines (3.4% vs. 5.4%, HR: 0.62, p < 0.001). Ischemic events were similar between the groups, resulting in a superior net clinical outcome (death, myocardial infarction, refractory ischemia, or major bleeding) favoring fondaparinux (GP IIb/IIIa subgroup 14.8% vs. 18.9%, HR: 0.77, p = 0.001 and thienopyridines subgroup 11.0% vs. 13.2%, HR: 0.82, p < 0.001).

CONCLUSIONS:

In patients receiving GP IIb/IIIa inhibitors or thienopyridines, fondaparinux reduces major bleeding and improves net clinical outcome compared with enoxaparin.

• Authors: Sanjit S Jolly, David P Faxon, Keith A A Fox, Rizwan Afzal, William E Boden, Petr Widimsky, P Gabriel Steg, Vicent Valentin, Andrez Budaj, Christopher B Granger, Campbell D Joyner, Susan Chrolavicius, Salim Yusuf, Shamir R Mehta
• Journal: Journal of the American College of Cardiology (J Am Coll Cardiol) Vol. 54 Issue 5 Pg. 468-76 (Jul 28 2009) ISSN: 1558-3597 [Electronic] United States
• PMID: 19628124 (Publication Type: Comparative Study, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Anticoagulants
• Enoxaparin
• Platelet Aggregation Inhibitors
• Platelet Glycoprotein GPIIb-IIIa Complex
• Polysaccharides
• Pyridines
• thienopyridine
• Fondaparinux

Topics

• Acute Coronary Syndrome (drug therapy)
• Aged
• Anticoagulants (pharmacology, therapeutic use)
• Drug Therapy, Combination
• Enoxaparin (pharmacology, therapeutic use)
• Female
• Fondaparinux
• Humans
• Male
• Platelet Aggregation Inhibitors (pharmacology, therapeutic use)
• Platelet Glycoprotein GPIIb-IIIa Complex (antagonists & inhibitors, drug effects)
• Polysaccharides (pharmacology, therapeutic use)
• Pyridines (pharmacology, therapeutic use)
• Treatment Outcome