Design

• Double-blind study involving 3232 patients with acute coronary syndromes (ACS) and unstable angina or non–Q-wave/non–ST-elevation (NSTE) myocardial infarction (MI) in the previous 24 hours
• Equal groups of 1616 patients randomized to AGGRASTAT (0.6 µg/kg/min for 30 minutes followed by a 0.15 µg/kg/min infusion) or heparin for 48 hours
• All patients also received acetylsalicylic acid (ASA) unless contraindicated
• Invasive assessment was discouraged within the first 48 hours of randomization. If percutaneous coronary intervention was performed, the study drug was discontinued.
• The primary endpoint was a composite of death, MI, or refractory ischemia at 48 hours. Patients were monitored for 30 days in a predefined exploratory analysis.

Results

• Incidence of the composite endpoint was significantly lower with AGGRASTAT (33% risk reduction, p=0.01 vs. heparin).
• Frequency of major and minor bleeding did not differ between the groups. Thrombocytopenia (platelet count <90,000/mm³) occurred more frequently with AGGRASTAT than with heparin (1.1% vs. 0.4%, p=0.04). However, platelet counts returned to normal after cessation of the study-drug infusions, without any other clinical sequelae.

Conclusions

• AGGRASTAT was generally well tolerated and reduced ischemic events during the 48-hour infusion period when revascularization procedures were not performed.
• At 30 days, mortality was lower among the patients given AGGRASTAT; the incidence of refractory ischemia and MI was not reduced.

In the PRISM study, patients with ACS and unstable angina or non–Q-wave/NSTE MI who received AGGRASTAT and ASA showed a significantly lower risk of death than those who received heparin and ASA (p=0.02).
Adapted from PRISM Study Investigators¹