Collaborative Angiographic Patency Trial Of Recombinant Staphylokinase (CAPTORS II)

A fibrinolytic agent more effective than streptokinase available for bolus injection with reasonable cost-effectiveness is a desirable goal. Pilot studies with bolus pegulated staphylokinase (PEG-Sak) have revealed excellent Thrombolysis In Myocardial Infarction (TIMI) 3 60-minute flow.

We evaluated patients with acute ST-elevation myocardial infarction within 6 hours of chest pain onset to determine a dose of PEG-Sak that had at least equal efficacy to recombinant tissue plasminogen activator (rt-PA) while maintaining an acceptable safety profile. After the initial study of 38 patients, of whom 27 received PEG-Sak, enrollment was temporarily halted because 3 patients receiving PEG-Sak had intracranial hemorrhage: 1 at a dose of 0.15 mg/kg and 2 at a dose of 0.05 mg/kg. Overall, 378 patients were studied across a PEG-Sak dose range from 0.01 mg/kg to 0.015 mg/kg, and 122 patients received accelerated rt-PA. At the lowest dose of PEG-Sak studied, 0.01 mg/kg, there was suggestive evidence of attenuation of efficacy; the point estimate for TIMI 3 flow was 24% (95% CI 9%-38%). At doses of 0.01875 to 0.0375 mg/kg (n = 314), TIMI 3 flow rates were 33% (95% CI 27%-38%), whereas the TIMI 3 flow was 41% (95% CI 20%-61%) at the highest PEG-Sak dose studied, 0.05 mg/kg (n = 23), which was similar to that found with rt-PA, 41% (95% CI 32%-50%).

The efficacy of PEG-Sak, coupled with its ease of administration, provide further impetus for further study in acute myocardial infarction.