Anti-inflammatory therapy for recurrent in-stent restenosis (AI-ISR): study protocol for a prospective, randomised,...

Recurrent in-stent restenosis (RISR) remains a major therapeutic challenge in patients undergoing percutaneous coronary intervention (PCI), with a high incidence of repeat revascularisation and increased mortality. Immune-mediated inflammation has been implicated in the pathogenesis of RISR. This trial aims to evaluate the clinical efficacy and safety of two anti-inflammatory strategies-low-dose colchicine and prednisone-on reducing ISR recurrence and cardiovascular events.

This is a multicentre, prospective, randomised, open-label controlled trial enrolling 252 patients with RISR. Following successful PCI, patients are randomly assigned (1:1:1) to receive: (1) standard medical therapy (control group); (2) colchicine 0.5 mg/day (colchicine group) or (3) prednisone 0.5 mg/kg/day, tapered monthly to 5-10 mg/day over 12 months (prednisone group). All groups receive background standard therapy per guidelines. The primary endpoint is angiographically confirmed ISR of the target lesion at 12 months post PCI. Secondary endpoints include the incidence of major adverse cardiovascular and cerebrovascular events (cardiovascular death, myocardial infarction, stroke and target vessel revascularisation), target lesion revascularisation and revascularisation of non-target coronary lesions within 12 months.

This trial has received ethical approval from the Ethics Committee of Fuwai Hospital (Chinese Academy of Medical Sciences and Peking Union Medical College), which acts as the central institutional review board. All participants will provide written informed consent. Study results will be disseminated via peer-reviewed journals and conference presentations.

ClinicalTrials.gov, NCT06090890. Registered 15 October 2023, https://clinicaltrials.gov/study/NCT06090890.