This study was designed to identify whether there is a measurable reduction in inflammation in walls of intracranial aneurysms with oral dimethyl fumarate.

Intracranial aneurysm (IA) is a common cerebrovascular disease and the main cause of nontraumatic subarachnoid hemorrhage. Once ruptured, it will cause a high mortality rate, and nearly half of the survivors will also have disabilities. After comparing surgical risk and rupture risk, a significant proportion of patients with intracranial aneurysms choose conservative observation.

Previous studies suggest that inflammation of aneurysmal wall is a high-risk factor of rupture. Dimethyl fumarate (DMF) acts as an anti-inflammatory agent by activating nuclear factor erythroid 2-related factor 2(Nrf2) and other pathways. Animal experiments found dimethyl fumarate reduces the formation and rupture of intracranial aneurysms.

MRI High-resolution vessel wall imaging (HR-VWI) has become a valuable method to assess the Wall of unruptured intracranial aneurysms. Using HR-VWI, it may be possible to detect smaller or more subtle areas of signal enhancement and change, which may give a more precise understanding of the pathology.

In this study, DMF was evaluated for its ability to reduce inflammation of the aneurysm wall measured with High-resolution Vessel Wall Imaging (HR-VWI).

Inclusion Criteria:

1. Male or female aged ≥18 years.
2. Unruptured IA of ≥3mm identified on imaging (CT, MRI or digital subtraction angiography).
3. Aneurysm wall enhancement identified by HR-VWI before treatment.
4. Ability to understand the objective of the trial with provision of written informed consent.

Exclusion Criteria:

1. MRI contraindications (metallic implant, contrast allergy, claustrophobia, etc).
2. Planned treatment of the aneurysm within 12 months.
3. Current treatment with drugs that might have an anti-inflammatory effect (aspirin, statins, immunosuppressive drugs, etc.).
4. Severely impaired liver or renal function.
5. Retreatment of recurrent aneurysm.
6. Pregnant or lactating women.
7. Malignant diseases (liver disease, kidney disease, congestive heart failure, malignant tumours, etc.).
8. Poor compliance.

Data are available on reasonable request.

starting 6 months after publication

Data are available on reasonable request.

The patients with intracranial aneurysms will be numbered and randomly divided into two groups, 30 patients in each group, and seal them. Through blind method, one group will be given dimethyl fumarate enteric capsule (the initial dose is 120 mg twice a day, and after 7 days, the dose will be increased to the maintenance dose of 240 mg twice a day, for 6 months). The other group took placebo with the same appearance (color, taste, size, shape) as the test drug.