Description: IC50 Value: 4.5nM (Ki); 10nM(Thrombin-induced platelet aggregation) [1] Dabigatran is a reversible and selective, direct thrombin inhibitor (DTI) undergoing advanced clinical development as its orally active prodrug,dabigatran etexilate. in vitro: Dabigatran selectively and reversibly inhibited human thrombin(Ki: 4.5 nM) as well as thrombin-induced platelet aggregation (IC(50): 10 nM), while showing no inhibitory effect on other platelet-stimulating agents.Thrombin generation in platelet-poor plasma (PPP), measured as the endogenous thrombin potential (ETP) was inhibited concentration-dependently (IC(50): 0.56 microM). Dabigatran demonstrated concentration-dependent anticoagulant effects in various species in vitro, doubling the activated partial thromboplastin time (aPTT), prothrombin time (PT) and ecarin clotting time (ECT) in human PPP at concentrations of 0.23, 0.83 and 0.18 microM, respectively [1]. in vivo: Dabigatran prolonged the aPTT dose-dependently after intravenous administration in rats (0.3, 1 and 3 mg/kg) and rhesus monkeys (0.15, 0.3 and 0.6 mg/kg). Dose- and time-dependent anticoagulant effects were observed with dabigatran etexilate administered orally to conscious rats (10, 20 and 50 mg/kg) or rhesus monkeys (1, 2.5 or 5 mg/kg), with maximum effects observed between 30 and 120 min after administration, respectively [1]. Patients treated with dabigatran etexilate experienced fewer ischaemic strokes (3.74 dabigatran etexilate vs 3.97 warfarin) and fewer combined intracranial haemorrhages and haemorrhagic strokes (0.43 dabigatran etexilate vs 0.99 warfarin) per 100 patient-years [2]. Clinical trial: An Evaluation of the Pharmacokinetics and Pharmacodynamics of Oral Dabigatran Etexilate in Hemodialysis Patients . Phase1