Comparison of fondaparinux and enoxaparin in acute coronary syndromes.
BACKGROUND
The combined use of anticoagulants, antiplatelet agents, and invasive coronary procedures reduces ischemic coronary events but also increases bleeding in patients with acute coronary syndromes. We therefore assessed whether fondaparinux would preserve the anti-ischemic benefits of enoxaparin while reducing bleeding.


METHODS
We randomly assigned 20,078 patients with acute coronary syndromes to receive either fondaparinux (2.5 mg daily) or enoxaparin (1 mg per kilogram of body weight twice daily) for a mean of six days and evaluated death, myocardial infarction, or refractory ischemia at nine days (the primary outcome); major bleeding; and their combination. Patients were followed for up to six months.


RESULTS
The number of patients with primary-outcome events was similar in the two groups (579 with fondaparinux [5.8 percent] vs. 573 with enoxaparin [5.7 percent]; hazard ratio in the fondaparinux group, 1.01; 95 percent confidence interval, 0.90 to 1.13), satisfying the noninferiority criteria. The number of events meeting this combined outcome showed a nonsignificant trend toward a lower value in the fondaparinux group at 30 days (805 vs. 864, P=0.13) and at the end of the study (1222 vs. 1308, P=0.06). The rate of major bleeding at nine days was markedly lower with fondaparinux than with enoxaparin (217 events [2.2 percent] vs. 412 events [4.1 percent]; hazard ratio, 0.52; P<0.001). The composite of the primary outcome and major bleeding at nine days favored fondaparinux (737 events [7.3 percent] vs. 905 events [9.0 percent]; hazard ratio, 0.81; P<0.001). Fondaparinux was associated with a significantly reduced number of deaths at 30 days (295 vs. 352, P=0.02) and at 180 days (574 vs. 638, P=0.05).


CONCLUSIONS
Fondaparinux is similar to enoxaparin in reducing the risk of ischemic events at nine days, but it substantially reduces major bleeding and improves long term mortality and morbidity. (ClinicalTrials.gov number, NCT00139815.).
Population Health Research Institute, McMaster Clinic, Hamilton General Hospital, 237 Barton St. East, Hamilton, ON L8L 2X2, Canada.
Salim
S
Yusuf
Shamir R
SR
Mehta
Susan
S
Chrolavicius
Rizwan
R
Afzal
Janice
J
Pogue
Christopher B
CB
Granger
Andrzej
A
Budaj
Ron J G
RJ
Peters
Jean-Pierre
JP
Bassand
Lars
L
Wallentin
Campbell
C
Joyner
Keith A A
KA
Fox
D000368:Aged; D000789:Angina, Unstable / Q000188:drug therapy* / Q000401:mortality / Q000628:therapy; D015906:Angioplasty, Balloon, Coronary; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D017984:Enoxaparin / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D000077425:Fondaparinux; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000401:mortality / Q000628:therapy; D011134:Polysaccharides / Q000009:adverse effects / Q000627:therapeutic use*; D012008:Recurrence; D020521:Stroke; D016019:Survival Analysis; D016896:Treatment Outcome
D000925:Anticoagulants; D017984:Enoxaparin; D011134:Polysaccharides; D000077425:Fondaparinux