title: A randomized clinical trial comparing long-term clopidogrel vs aspirin monotherapy beyond dual antiplatelet therapy after drug-eluting coronary stent implantation: Design and rationale of the Harmonizing Optimal Strategy for Treatment of coronary artery stenosis-Extended Antiplatelet Monotherapy (HOST-EXAM) trial.
abstract: Percutaneous coronary intervention (PCI) has been developed by drug-eluting stent (DES), but stent implantation has brought the issue of stent thrombosis and optimal antiplatelet therapy. Guidelines recommend at least 6- to 12 months of dual antiplatelet therapy (DAPT) with aspirin and a P2Y12receptor inhibitor such as clopidogrel. Beyond DAPT after PCI with DES, however, there has been still a debate for antiplatelet regimen. Therefore, we report on the upcoming HOST-EXAM trial (NCT02044250), which will evaluate the efficacy and safety of aspirin and clopidogrel monotherapies beyond DAPT after DES implantation.
  
  
  METHODS
  The HOST-EXAM is a prospective, randomized, open-label, multicenter, comparative effectiveness trial, to compare between clopidogrel (75 mg once daily) and aspirin (100 mg once daily) as long-term antiplatelet agents. A total of 5,530 patients with no clinical events during combined antiplatelet therapy for 12±6 months after index PCI will be screened, enrolled, and randomized to either group (1:1 ratio) receiving antiplatelet monotherapy for 2 years. The primary endpoint will be the rate of clinical events defined as a composite of all-cause death, nonfatal myocardial infarction, stroke, readmission due to acute coronary syndrome, or major bleeding at 24 months after randomization.
  
  
  CONCLUSIONS
  The HOST-EXAM will be the first large-scale randomized controlled study to directly compare the efficacy and safety of long-term antiplatelet monotherapy beyond DAPT after DES implantation. This study will provide clinical evidence to establish optimal regimen for long-term antiplatelet therapy after DES implantation.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Healthcare System Gangnam Center, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Heesun
authors.initials: H
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Cardiovascular Center, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Bon-Kwon
authors.initials: BK
authors.lastname: Koo
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Cardiovascular Center, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Kyung Woo
authors.initials: KW
authors.lastname: Park
authors.affiliation: Ulsan University Hospital, Ulsan, Republic of Korea.
authors.forename: Eun-Seok
authors.initials: ES
authors.lastname: Shin
authors.affiliation: CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Sang Wook
authors.initials: SW
authors.lastname: Lim
authors.affiliation: Korea University Guro Hospital, Seoul, Republic of Korea.
authors.forename: Seung-Woon
authors.initials: SW
authors.lastname: Rha
authors.affiliation: Chungbuk National University, College of Medicine, Cheongju, Republic of Korea.
authors.forename: Jang-Whan
authors.initials: JW
authors.lastname: Bae
authors.affiliation: National Health Insurance Corporation Ilsan Hospital, Goyang, Republic of Korea.
authors.forename: Dong Woon
authors.initials: DW
authors.lastname: Jeon
authors.affiliation: Wonkwang University Hospital, Iksan, Republic of Korea.
authors.forename: Seok-Kyu
authors.initials: SK
authors.lastname: Oh
authors.affiliation: Keimyung University Dongsan Medical Center, Daegu, Republic of Korea.
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Hur
authors.affiliation: Kangbuk Samsung Medical Center, Sungkyunkwan University, Seoul, Republic of Korea.
authors.forename: Bum-Su
authors.initials: BS
authors.lastname: Kim
authors.affiliation: Yeungnam University Medical Center, Daegu, Republic of Korea.
authors.forename: Jung-Hee
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Dong-A University Hospital, Busan, Republic of Korea.
authors.forename: Tae-Ho
authors.initials: TH
authors.lastname: Park
authors.affiliation: Kangnam Sacred Heart Hospital, Hallym University, Seoul, Republic of Korea.
authors.forename: Nam Ho
authors.initials: NH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Cardiovascular Center, Seoul National University Hospital, Seoul, Republic of Korea. Electronic address: usahyosoo@gmail.com.
authors.forename: Hyo-Soo
authors.initials: HS
authors.lastname: Kim
mesh_terms: D054058:Acute Coronary Syndrome / Q000453:epidemiology; D001241:Aspirin / Q000008:administration & dosage*; D002423:Cause of Death; D000077144:Clopidogrel; D023921:Coronary Stenosis / Q000628:therapy*; D004359:Drug Therapy, Combination; D054855:Drug-Eluting Stents; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D009026:Mortality; D009203:Myocardial Infarction / Q000453:epidemiology; D062645:Percutaneous Coronary Intervention; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D020521:Stroke / Q000453:epidemiology; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin