Welcome to the website of the PROTECT-U trial


In patients with an unruptured intracranial aneurysm, the aneurysm is currently left untreated if the presumed complication risk of preventive neurosurgical or endovascular intervention is higher than the risk of rupture. In these patients, aneurysm wall inflammation and blood pressure are attractive modifiable risk factors of aneurysm rupture and growth.

PROTECT-U (Prospective Randomized Open-label Trial to Evaluate risk faCTor management in patients with Unruptured intracranial aneurysms) is the first ever randomized trial to investigate if a medical strategy reduces the risk of aneurysm rupture or growth in patients not undergoing preventive neurosurgical or endovascular aneurysm treatment. Patients 18 years or older with an intradural, saccular unruptured intracranial aneurysm on MR or CT angiography are eligible if it is decided to refrain from preventive neurosurgical or endovascular intervention, and to monitor the aneurysm on a regular basis for growth.

We hypothesize that a treatment strategy consisting of acetylsalicylic acid 100mg/day plus intensive blood pressure treatment (targeted systolic blood pressure <120mmHg, monitored with a home blood pressure measuring device) reduces the risk of aneurysm rupture or growth compared with standard care (no acetylsalicylic acid, targeted systolic blood pressure <140mmHg, no home blood pressure measuring device).

We aim to randomise 776 patients 1:1 to either the intervention arm or standard care. The primary outcome is aneurysm rupture or growth (increase in any aneurysm diameter by ≥1mm) on repeated MR or CT angiography within 36±6 months after randomisation. The trial has a PROBE design (prospective, randomized, open-label trial with blinded outcome assessment).

The PROTECT-U trial is registered at clinicaltrials.gov: NCT03063541.