Direct thrombin inhibitors.

Direct thrombin inhibitors may offer advantages over indirect thrombin inhibitors in the management of patients with acute coronary syndromes (ACS). Two direct thrombin inhibitors, hirudin and bivalirudin, have been investigated in Phase II and Phase III clinical trials. Based on the results of a meta-analysis of study data from 25,000 patients, hirudin appears to be more effective than unfractionated heparin (UFH) in the treatment of patients with ACS, but it is associated with an increased rate of major bleeding. A meta-analysis of a smaller patient population has suggested that bivalirudin, too, may be more efficacious than UFH and may also be safer.