Angiotensin II (Ang II) is implicated in the development of in-stent restenosis (ISR). Ang II- and AT1-receptor blockade could possibly reduce ISR. We enrolled 206 patients into a prospective double-blind, placebo-controlled, multicenter randomized trial of candesartan cilexitil 16 mg to test this notion. Mean lumen diameter (MLD) was the primary objective measured by quantitative coronary angiography and intravascular ultrasound. The Candesartan Group showed a trend towards a larger MLD at follow up without significant differences in the binary ISR rate. In vessels < 2.75 mm, we found a larger MLD in the treatment group after 6 months. This might indicate the potential benefit of AT1-receptor blocker therapy for certain subgroups when percutaneous coronary intervention is performed with bare-metal stent implantation.