Methods and Results: ASET-JAPAN is a prospective, multicenter, single-arm pilot study that completed enrolment of 206 patients from 12 Japanese centers in September 2022. Patients with native de-novo coronary lesions and a SYNTAX score <23 were treated exclusively with biodegradable-polymer platinum-chromium everolimus-eluting stent(s). Patients were loaded with standard dual antiplatelet therapy (DAPT) and following successful PCI and optimal stent deployment, they received low-dose prasugrel (3.75 mg/day) monotherapy for 3 months. The primary ischemic endpoint was a composite of cardiac death, spontaneous target-vessel myocardial infarction, or definite stent thrombosis. The primary bleeding endpoint was Bleeding Academic Research Consortium (BARC) type 3 or 5. At 3-month follow-up, there were no primary bleeding or ischemic events, or any stent thrombosis.