Routine upstream initiation vs deferred selective use of glycoprotein IIb/IIIa inhibitors in acute coronary syndromes: the ACUITY Timing trial

Abstract

Context: In patients with moderate- and high-risk acute coronary syndromes (ACS) who undergo an early, invasive treatment strategy, current guidelines recommend administration of platelet glycoprotein IIb/IIIa (Gp IIb/IIIa) inhibitors, either upstream to all patients prior to angiography or deferred for selective use in the catheterization laboratory just prior to angioplasty. The preferred approach is undetermined.

Objective: To determine the optimal strategy for the use of Gp IIb/IIIa inhibitors in patients with moderate- and high-risk ACS undergoing an early, invasive treatment strategy.

Design: Prospective, randomized, open-label trial with 30-day clinical follow-up.

Setting: Four hundred fifty academic and community-based institutions in 17 countries.

Patients: A total of 9207 patients with moderate- and high-risk ACS undergoing an invasive treatment strategy.

Interventions: Patients were randomly assigned to receive either routine upstream (n=4605) or deferred selective (n=4602) Gp IIb/IIIa inhibitor administration, respectively.

Main outcome measures: The primary outcome was assessment of noninferiority of deferred Gp IIb/IIIa inhibitor use compared with upstream administration for the prevention of composite ischemic events (death, myocardial infarction, or unplanned revascularization for ischemia) at 30 days, using a 1-sided alpha level of .025. Major secondary end points included noninferiority or superiority of major bleeding and net clinical outcomes (composite ischemia or major bleeding).

Results: Glycoprotein IIb/IIIa inhibitors were used more frequently (98.3% vs 55.7%, respectively) and for a significantly longer duration (median, 18.3 vs 13.1 hours; P<.001) in patients in the upstream group compared with the deferred group. Composite ischemia at 30 days occurred in 7.9% of patients assigned to deferred use compared with 7.1% of patients assigned to upstream administration (relative risk, 1.12; 95% confidence interval, 0.97-1.29; P = .044 for noninferiority; P = .13 for superiority); as such, the criterion for noninferiority was not met. Deferred use compared with upstream use resulted in reduced 30-day rates of major bleeding (4.9% vs 6.1%, respectively; P<.001 for noninferiority; P = .009 for superiority) and similar rates of net clinical outcomes (11.7% vs 11.7%; P<.001 for noninferiority; P = .93 for superiority).

Conclusions: Among patients with moderate- and high-risk ACS undergoing an invasive treatment strategy, deferring the routine upstream use of Gp IIb/IIIa inhibitors for selective administration in the cardiac catheterization laboratory only to patients undergoing percutaneous coronary intervention resulted in a numerical increase in composite ischemia that, while not statistically significant, did not meet the criterion for noninferiority. This finding was offset by a significant reduction in major bleeding.

Trial registration: ClinicalTrials.gov Identifier: NCT00093158.