A randomized non-inferiority study of low-dose and standard-dose ticagrelor after intervention for acute coronary syndrome: study protocol for the TIGER STUDY

BACKGROUND: Current guidelines recommend that patients with acute coronary syndrome (ACS) who have successfully undergone percutaneous coronary intervention (PCI) should continue to use dual antiplatelet therapy (DAPT) for 12 months. The long-term use of standard-dose dual antiplatelet therapy will increase the risk of bleeding. An optimized antiplatelet strategy that can prevent ischemic events and reduce the risk of bleeding remains to be explored. METHODS: The study is a prospective, multicenter, randomized, open-label, controlled study involving 2090 patients from six clinical centers in China. Through the interactive web response system (IWRS), ACS patients undergoing successful PCI will be randomly divided into the low-dose ticagrelor group or the normal-dose ticagrelor group, after taking 100 mg aspirin and 90 mg ticagrelor bid for 1 week. The primary endpoint is a composite of cardiovascular death, non-fatal myocardial infarction, stent thrombosis, repeat revascularization, and stroke. The secondary endpoints are bleeding events of grade 2 or higher according to Bleeding Academic Research Consortium [BARC] criteria, cardiovascular death, acute myocardium infarction, and coronary revascularization at 1 year. DISCUSSION: Recent studies have confirmed that 90 mg ticagrelor alone can safely and effectively reduce bleeding without increasing ischemic events of patients with ACS after PCI. Compared with standard-dose DAPT, whether low-dose ticagrelor combined with aspirin can ensure the anti-ischemic effect while reducing the bleeding risk remains unclear in Chinese patients. The TIGER study will be the first large-scale, multicenter study to compare the efficacy and safety of low-dose and standard-dose ticagrelor combined with aspirin in ACS patients 1 week after successful PCI. TRIAL REGISTRATION: Clinicaltrials.gov NCT04255602. Registered on 5 February 2020.