Rationale and Design of ST-ON-SET: Assessment of Antiplatelet Effect after Ticagrelor Loading Dose in STEMI Patients and NSTEMI Patients

Hongyi Wu, Yinman Wang, Huajie Xu, Juying Qian, Junbo Ge


Background: Delayed platelet inhibition by ticagrelor has been initially documented in STEMI subjects. To the best of our knowledge, no data exists about the direct description of early onset of platelet inhibition after ticagrelor loading dose (LD) in different clinical forms of ACS, especially in Chinese patients. The ST-ON-SET study is designed to address this unmet need.

Method/Design: The ST-ON-SET study is a single center, prospective, observational, open-label, investigator-initiated study. Platelet inhibition assessed by Light transmittance aggregometry (LTA) and plasma concentrations of ticagrelor and its metabolites would be investigated serially. The primary outcome is the inhibition of platelet aggregation measured by LTA at 2 hours after ticagrelor LD. Moreover, baseline inflammatory and thrombotic biomarkers would be measured to investigate the potential underlying influences of platelet inhibition.

Conclusion: The study is designed to characterize pharmacokinetic and pharmacodynatic profiles of ticagrelor LD in Chinese STEMI and NSTEMI patients. Furthermore, preliminary investigation of the underlying mechanism of initial delayed platelet inhibition by ticagrelor would be conducted.


acute coronary syndrome; ticagrelor; pharmacokinetics; pharmacodynamics

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DOI: https://doi.org/10.17987/icfj.v8i0.320

Copyright (c) 2016 Hongyi Wu, Yinman Wang, Huajie Xu, Juying Qian, Junbo Ge

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