The goal of this clinical trial is to assess the safety and tolerability of colchicine for preventing intracerebral haemorrhage (ICH) recurrence in patients with cerebral amyloid angiopathy (CAA)-ICH at high risk of recurrence.

The main questions it aims to answer are:

• Is colchicine safe for CAA-ICH patients?
• Is colchicine well tolerated for CAA-ICH patients? Researchers will compare colchicine to a placebo (a look-alike substance that contains no drug) to see if colchicine is safe and tolerable for CAA-ICH patients and works to prevent ICH recurrence.

Participants will:

• Take colchicine or a placebo every day for 12 months
• Receive telephone follow-ups at 3 and 9 months, and visit the clinic at 6 and 12 months for checkups and tests
• Control blood pressure and improve lifestyle

The CARE-ICH study is a multicenter, randomized, double-blind, placebo-controlled, phase II trial. The primary objective of the CARE-ICH study is to assess the safety and tolerability of colchicine for preventing ICH recurrence in patients with CAA-ICH at high risk of recurrence, as well as provide a preliminary estimate of the feasibility and efficacy for planning a phase III trial.

Patients with CAA-ICH and a high risk of recurrence-defined as 1 prior symptomatic ICH and presence of cortical superficial siderosis, or ≥2 prior symptomatic ICHs-within 3 months of their most recent ICH will be enrolled and randomized in a 1:1 ratio to receive either oral colchicine 0.5 mg once per day or matching placebo for 1 year, in addition to standard care, including blood pressure control and lifestyle modifications. Follow-up visits will take place at 3, 6, 9, and 12 months. Each visit will include assessments of adverse events, medication adherence, and clinical outcomes. The primary outcomes are the incidence of treatment-emergent adverse events and treatment tolerability.

Inclusion Criteria:

• Age ≥55 years;
• Diagnosed with "probable CAA with supporting pathology" or "probable CAA" according to the modified Boston criteria (version 1.5);
• High risk of recurrent ICH, defined as: 1 prior symptomatic ICH and presence of cortical superficial siderosis (cSS), or ≥2 prior symptomatic ICHs;
• Time interval since symptom onset of the most recent ICH: ≤3 months (earlier enrollment is preferred if criteria are met);
• Modified Rankin Scale (mRS) score ≤4 at randomization;
• Written informed consent from the participant or their legally authorized representative before study enrollment.

Exclusion Criteria:

• Secondary causes of ICH;
• Pre-existing moderate-to-severe renal, liver or blood disorders (anaemia [hemoglobin <10g/dL], thrombocytopaenia [platelet count <100×109/L], leucopenia [white blood cell <3×109/L], cirrhosis or severe hepatic dysfunction, renal insufficiency [estimated glomerular filtration rate (eGFR) <15mL/min]);
• Prior diagnosis of gout, peripheral neuropathy, myopathy, inflammatory bowel disease or chronic diarrhea;
• Concurrent treatment with regular immune-suppressant (corticosteroids, cyclophosphamide, azathioprine, mycophenolate mofetil, rituximab), moderate-to-strong CYP3A4 inhibitors (atazanavir, clarithromycin, darunavir/ritonavir, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, tipranavir/ritonavir) or P-glycoprotein inhibitors (cyclosporine, ranolazine);
• Known allergy, sensitivity or intolerance to colchicine;
• Contraindications or inability to complete brain MRI or susceptibility weighted imaging (SWI) scans;
• Pregnancy or breastfeeding;
• Recent participation in any other interventional study in the past 30 days before enrollment;
• Not expected to survive the follow-up period;
• Inability to adhere to study procedures;
• Any condition in which investigators believe that participating in this study may be harmful to the patient.

Data collected for the study can be made available to other researchers on reasonable request and after signing appropriate data sharing agreements.

Double-blind