Melagatran is an orally available, direct synthetic thrombin inhibitor that does not require endogenous cofactors other than thrombin and does not significantly interact with any other enzymes in the coagulation cascade or with the fibrinolytic enzymes.

METHODS: To test the hypothesis that a regimen consisting of an oral thrombin inhibitor would delay or prevent occlusive clot formation, anesthetized dogs were given melagatran (1.5, 2.5 mg/kg) via nasogastric tube, and 15 minutes later, a potent thrombogenic stimulus in the form of an anodic current (100 μA) was applied to the intimal surface of the stenotic left anterior descending coronary artery (LAD).
RESULTS One of the dogs given high-dose melagatran did not develop thrombotic occlusion of the LAD during the entire 4-hour observation period. In the melagatran-treated dogs, coronary artery occlusions occurred during the observation period in 68% (low-dose) and 75% (high-dose) of the dogs.[2]