18 type II diabetes mellitus patients with coronary artery disease (CAD) have been studied. Tissue plasminogen activator (t-PA) antigen and activity, plasminogen activator inhibitor (PAI) antigen and activity, thrombin-antithrombin III (TAT) complexes were determined in blood samples. Diabetic CAD patients showed higher TAT levels with clearly increased PAI levels whereas t-PA levels levels were similar in patients and controls. Long term defibrotide treatment induced marked changes in fibrinolytic parameters of these diabetic patients with CAD with increased t-PA activity, that could be related to an evident reduction of PAI antigen and activity. Drugs able to modulate PAI activity may be useful in clinical conditions at high risk of thrombotic vascular complications like diabetics with stable angina.