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Background and Objective: There is an unmet need for a safer anticoagulant since bleeding remains a concern with currently approved anticoagulants. Coagulation factor XI (FXI) is an attractive anticoagulant drug target with limited a role in physiological hemostasis. The objective of this study was to evaluate the safety, pharmacokinetics, and pharmacodynamics of SHR2285, a novel small molecule FXIa inhibitor, in healthy Chinese volunteers. Methods: The study consisted of single ascending doses part (part 1: 25–600 mg) and multiple ascending doses part (part 2: 100, 200, 300, and 400 mg). In both parts, subjects were randomized in a 3:1 ratio to receive SHR2285 or placebo orally. Blood, urine and feces samples were collected to describe its pharmacokinetic and pharmacodynamic profile. Results: In total, 103 healthy volunteers completed the study. SHR2285 was well tolerated. SHR2285 was absorbed rapidly with median time to maximum plasma concentration (Tmax) of 1.50 to 3.00 h. The geometric median half-life (t1/2) of SHR2285 varied from 8.74 to 12.1 h across 25–600 mg single dose. Total systemic exposure of metabolite SHR164471 was approximately 1.77- to 3.61-fold that of the parent drug. The plasma concentration of SHR2285 and SHR164471 reached steady state by the morning of Day 7, with low accumulation ratio (0.956–1.20 and 1.18–1.56, respectively). The increase in pharmacokinetic exposure of SHR2285 and SHR164471 was less than dose proportional. Food has minimal effect on the pharmacokinetics of SHR2285 and SHR164471. SHR2285 produced an exposure-dependent prolongation of activated partial thromboplastin time (APTT) and a decrease in FXI activity. The maximum FXI activity inhibition rate (geometric mean) at steady state was 73.27%, 85.58%, 87.77% and 86.27% for 100–400 mg, respectively. Conclusions: SHR2285 was generally safe and well tolerated in healthy subjects across a wide range of doses. SHR2285 exhibited a predictable pharmacokinetic profile and an exposure-related pharmacodynamic profile. ClinicalTrials.gov Identifier NCT04472819; registered on July 15, 2020. [ABSTRACT FROM AUTHOR]