This study is aimed at making a comparison of the safety and efficacy of standard drug therapy (control group), standard drugs combined with lose-dose colchicine therapy (colchicine group) and standard drug combined with prednisone therapy (prednisone group) in patients with coronary heart disease who suffered from recurrent In-stent restenosis (RISR).

This is a prospective, randomized, open-label, blinded-endpoint evaluation, single-center Study. A total of 252 RISR patients are planned to be enrolled in Fuwai Hospital, China. Then those included subjects will be randomized to standard drug therapy (control group), standard drugs combined with lose-dose colchicine therapy (colchicine group) and standard drug combined with prednisone therapy (prednisone group). The primary endpoint of the current study is target lesion ISR confirmed by coronary angiography for 12 months, and the secondary endpoint is Major adverse cardiovascular events (MACE: a composite of death, non-fatal myocardial infarction, non-fatal stroke, and target vascular revascularization) and each MACE component, target lesion revascularization, or other coronary artery disease revascularization for 12 months. The safety endpoint is adverse reactions to colchicine, adverse reactions of prednisone, or discontinued medication due to adverse reactions. In summary, the present study is to provide new evidence and strategy about anti-inflammatory therapy for recurrent In-stent restenosis after coronary intervention.

Inclusion Criteria:

1. CAD patients over 18 years old;
2. At least one coronary artery lesion meets the RISR criteria: target lesion ≥ 2 ISRs (stenosis of lumen diameter within the stent segment and within 5mm near and far of the stent ≥ 50%);
3. Intended intervention treatment for RISR lesions;
4. Acceptable for standard secondary prevention drug therapy for coronary heart disease, including dual antiplatelet therapy (DAPT) and statins;
5. Willing to participate in the trial and complete follow-up, signing an informed consent form approved by the ethics committee

Exclusion Criteria:

1. The previous interventional treatment situation is unknown;
2. The mechanism of intracavitary imaging to clarify ISR is operator-related (poor stent adhesion, incomplete dilation, and stent fracture);
3. Clearly diagnose vascular inflammatory diseases or connective tissue diseases (including arteritis, Behcet's disease, systemic lupus erythematosus, etc.) involving the coronary artery;
4. Immunosuppressive drugs, including glucocorticoids, have been used in the past 30 days;
5. There are contraindications to the use of prednisone or colchicine, including: serious infectious diseases, including active infection, hepatitis B, hepatitis C or AIDS patients; Hematological diseases, such as thrombocytopenia, severe anemia, leukemia, etc; Uncontrolled diabetes; Severe liver and kidney function damage; Active peptic ulcer or gastrointestinal bleeding; Severe osteoporosis (with previous pathological fractures); Inflammatory bowel disease or chronic diarrhea;
6. A history of malignant tumors within 3 years;
7. Cognitive impairment;
8. Not willing to participate or follow up

De-identified individual participant data will be securely stored and will be available only upon reasonable request and with approval from the study investigators, in accordance with BMJ Open's data-sharing policy.

De-identified individual participant data will be available only upon reasonable request and with approval from the study investigators, in accordance with BMJ Open's data-sharing policy.