GUSTO IIa Halted Amid Safety Concerns

The GUSTO IIa study has been discontinued because of a higher-than-expected incidence of fatal or severe strokes among patients treated with elevated doses of heparin or Behringwerke's hirudin (Circulation 1994; 90: 1631-37).

GUSTO IIa was begun last year with the aim of demonstrating that hirudin was more effective than heparin, when combined with thrombolysis, in preventing death or myocardial infarction within one month of treatment of patients with ischemic-type chest pain. The trial was discontinued in April, although the announcement was held back until the end of last month.

The overall stroke rate for patients on the anticoagulants was 1.8%, compared to 0.3% for those who did not receive the therapy (see table for breakdown). In GUSTO I, a stroke rate of 0.7% was observed. Addition of hirudin to the thrombolytic regimens seemed to confer the highest risk of stroke.