Effect of platelet glycoprotein IIb/IIIa receptor blockade with tirofiban on adverse cardiac events in women with unstable angina/non-ST–elevation myocardial infarction (PRISM-PLUS study)

Background Previous trials demonstrated the efficacy of platelet glycoprotein IIb/IIIa receptors blockade with tirofiban in reducing acute ischemic events in patients with unstable angina/non–ST-elevation myocardial infarction. Little is known about the effect of tirofiban among women with acute coronary syndromes. Objective We aimed to determine the benefit and safety of tirofiban plus heparin versus heparin alone on cardiac ischemic events among women with unstable angina/non–ST-elevation myocardial infarction. Method and results We performed a post hoc analysis of all women enrolled in the PRISM-PLUS trial. At early time points, there appeared to be a reduction of the primary composite end point of death, myocardial infarction, or refractory ischemia among women treated with tirofiban plus heparin (RR, 0.78 and 0.67) compared with women treated with heparin alone. However, at 30 and 180 days, there was no significant reduction of events with the combination therapy of tirofiban plus heparin (treatment-by-sex interaction, P = .05). Death or myocardial infarction was not significantly reduced by the combination therapy among women at all time points. Conclusions Although the effects of tirofiban in reducing the primary composite outcome were similar among men and women early in the study, there appeared to be a difference at the later time points. In particular, tirofiban was effective among men, but there was no clear effect among women at 30 and 180 days.