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Orme RC, Parker WAE, Thomas MR, et al. Study of Two Dose Regimens of Ticagrelor Compared with Clopidogrel in Patients Undergoing Percutaneous Coronary Intervention for Stable Coronary Artery Disease (STEEL-PCI). Circulation 2018. 129. Gross L, Trenk D, Jacobshagen C, et al. Genotype-Phenotype Association and Impact on Outcomes following Guided De-Escalation of Anti-Platelet Treatment in Acute Coronary Syndrome Patients: The TROPICAL-ACS Genotyping Substudy. Thromb Haemost 2018; 118:1656. 130. Tantry US, Bonello L, Aradi D, et al. Consensus and update on the definition of on-treatment platelet reactivity to adenosine diphosphate associated with ischemia and bleeding. J Am https://www.uptodate.com/contents/clopidogrel-resistance-and-clopidogrel-treatment-failure/print 30/33 7/5/23, 9:13 AM Clopidogrel resistance and clopidogrel treatment failure - UpToDate Coll Cardiol 2013; 62:2261. Topic 6684 Version 105.0 https://www.uptodate.com/contents/clopidogrel-resistance-and-clopidogrel-treatment-failure/print 31/33 7/5/23, 9:13 AM Clopidogrel resistance and clopidogrel treatment failure - UpToDate GRAPHICS Clopidogrel nonresponsiveness varies according to duration of therapy Relationship between frequency of patients and absolute change in aggregation ( Aggregation [percent]) in response to 5 mol/L ADP at 2 hours, 24 hours, 5 days, and 30 days after stenting. Aggregation (percent) is defined as baseline aggregation (percent) minus post-treatment aggregation (percent). Resistance, as defined herein, is Aggregation (percent) 10 percent. Resistance is present in those patients subtended by double-headed arrow. Curves represent normal distribution of data and were created by Statistica software. Reproduced with permission from: Gurbel PA, Bliden KP, Hiatt BL, O'Connor CM. Clopidogrel for coronary stenting: response variability, drug resistance, and the e ect of pretreatment platelet reactivity. Circulation 2003; 107:2908. Copyright 2003 Lippincott Williams & Wilkins. Graphic 87715 Version 5.0 https://www.uptodate.com/contents/clopidogrel-resistance-and-clopidogrel-treatment-failure/print 32/33 7/5/23, 9:13 AM Clopidogrel resistance and clopidogrel treatment failure - UpToDate Contributor Disclosures Udaya S Tantry, PhD No relevant financial relationship(s) with ineligible companies to disclose. Charles H Hennekens, MD, DrPH Patent Holder: Brigham and Women's Hospital [Co-inventor on patents concerning inflammatory markers and cardiovascular disease, C-reactive protein]. Consultant/Advisory Boards: Amgen [Migraine, cardiovascular disease]; UCB [Osteoporosis]. All of the relevant financial relationships listed have been mitigated. James L Zehnder, MD No relevant financial relationship(s) with ineligible companies to disclose. Paul A Gurbel, MD Equity Ownership/Stock Options: Merck [Cardiology]. Grant/Research/Clinical Trial Support: Amgen [Lipid-lowering therapy]; Bayer Healthcare [Antiplatelet therapy]; Haemonetics [Cardiology device]; Hikari Dx [Cardiology device]; Instrumentation Laboratory [Cardiology device]; Janssen [Antithrombotic therapy]; Nirmidas Biotech [COVID-19 biomarker]; Novartis [Lipid-lowering therapy]; Otitopic Inc [Antiplatelet therapy]; Precisio Biolog [COVID-19 biomarker]; R-Pharma International [Antithrombotic therapy]. Consultant/Advisory Boards: Adeno [Cardiology]; Bayer [Antiplatelet therapy]; Cleveland Clinic [Cardiology]; Innovative Sciences [Cardiology]; Janssen [Antiplatelet therapy]; Otitopic Inc [Antiplatelet therapy]. All of the relevant financial relationships listed have been mitigated. Lawrence LK Leung, MD No relevant financial relationship(s) with ineligible companies to disclose. Donald Cutlip, MD Consultant/Advisory Boards: MedAlliance [Drug-eluting balloon]. Other Financial Interest: Baim Institute for Clinical Research [Clinical research]. All of the relevant financial relationships listed have been mitigated. Todd F Dardas, MD, MS No relevant financial relationship(s) with ineligible companies to disclose. Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence. Conflict of interest policy https://www.uptodate.com/contents/clopidogrel-resistance-and-clopidogrel-treatment-failure/print 33/33