Introduction Flow diversion (FD) is increasingly used for the treatment of intracranial aneurysms due to its efficacy and performance. Initially limited to large and giant ICA aneurysms, the FD approach has progressively enlarged to distal and bifurcation aneurysms. Due to the need for dual antiplatelet treatment (DAPT) to prevent thromboembolic complications, indications for FD are still limited to unruptured and recanalized aneurysms. To overcome this limitation, FDs with surface modification have been introduced and are currently under evaluation. The Hydrophilic Polymer Coating (HPC) is a glycocalyx-like surface modification that prevents platelet aggregation.

Aim of Study COATING is the unique randomized controlled trial dedicated to the assessment of a surface-modified FD (p64-MW-HPC; phenox GmbH, Bochum, Germany).

Methods The subjects are randomized 1:1 in 2 arms: p64-MW (bare) and DAPT (prasugrel or ticagrelor + aspirin), and p64-MW-HPC (surface-modified) under single antiplatelet treatment (SAPT; prasugrel or ticagrelor). The primary endpoint is the rate of thromboembolic complications as assessed by an independent core lab on DWI-MRI 48 hours after the procedure. Secondary endpoints are evaluating safety, performance and efficacy.

Maximum enrollment is 200 subjects.

Results Fourteen European centers are currently active. First inclusion occurred in September 2021. Today 82 subjects have been randomised.

Conclusion Surface-modified flow diverters will potentially change the treatment strategy for such aneurysmal subjects. COATING is the first RCT to evaluate a surface-modified FD under SAPT.

Disclosure of Interest LP is consultant for Wallaby-Phenox.