A prospective, multicenter, randomized OCT study of early neointimal condition at first and second months after BuMA Supreme stent versus XIENCE stent implantation in high-bleeding-risk coronary artery disease patients: study protocol for a randomized controlled trial

BACKGROUND: Earlier vascular healing after drug-eluting stent (DES) implantation may reduce the incidence of late stent thrombosis and provide theoretical evidence to shorten dual antiplatelet therapy duration in patients with high bleeding risks. The BuMA supreme stent is a newly developed DES-coated with the sirolimus by using the international patent electronic grafted eG™ technology. Previous randomized trials showed that BuMA stents had better stent-strut coverage at 3-month follow-ups, which were evaluated by optical coherence tomography (OCT). However, there have been a limited number of studies that are directly evaluating the extent of neointima formation at the first and second months after stent implantation in high-bleeding-risk patients with coronary artery disease. This clinical trial is designed to demonstrate the non-inferiority of the BuMA supreme stent compared to the XIENCE stent in early neointimal formation. METHODS/DESIGN: This is a prospective, multicenter, randomized trial. Forty patients will be assigned into the first-month OCT group, and another 40 patients into the second-month OCT group. The patients in each cohort will be randomized again into two groups in a 1:1 ratio, either being implanted with the BuMA Supreme stent or the Xience V/Prime/Xpedition stent. The primary endpoint is stent-strut neointimal coverage rate (%) at the first and second months, respectively. Secondary endpoints include neointimal hyperplasia area/volume, neointimal hyperplasia thickness, stent-strut malapposition rate, late lumen loss (LLL), restenosis rate, device/lesion/clinical success rate, device-oriented composite endpoints at the first and second months, stent thrombosis and other serious adverse events and bleeding events at follow-up. DISCUSSION: The results will provide the first accurate imaging evidence on neointimal formation of the BuMA Supreme stent and the Xience stent at 1-2 months post PCI. The result should inspire further exploration and adjustment of DAPT treatments. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT02747329 . Registered on 21 April 2016. Last updated 17 May 2018.