Abstract 243: Proximal Internal Carotid Artery Acute Stroke Secondary to Tandem or Local Occlusion (PICASSO) Thrombectomy Trial

Background and Aims Tandem arterial anterior circulation intracranial occlusions (TO) are acute ischemic strokes (AIS) that involve an extra‐cranial carotid lesion (ECL) with severe carotid stenosis (≥ 70%) of the internal carotid artery (ICA) with an intracranial vessel occlusion. TOs were excluded and underrepresented in most of the randomized control trials (RCT). There is no scientific evidence on how to treat the ECL from RCT. The Proximal Internal Carotid Artery Acute Stroke Secondary to Tandem or Local Occlusion (PICASSO) Thrombectomy Trial, aims to evaluate whether acute carotid stenting or non‐stenting management leads to better patient functional outcomes. Methods The PICASSO Trial is a prospective, phase III, randomized, open‐label, blinded‐endpoint controlled trial (PROBE Design), with planned enrollment of 404 patients. Patients will be randomized 1:1 into either mechanical thrombectomy plus extracranial carotid stenting (MT+CAS) or MT plus non‐stenting methods (MT+CAT). The original PICASSO study design included a sub‐randomization of the MT+CAS arm by antiplatelet regimen (either MT+CAS IV‐AP or MT+CAS PO‐IV), however, recent modifications to the clinical protocol allow treating physicians to determine all periprocedural management. The primary efficacy endpoint is the 90‐day mRS ordinal shift analysis of functional patient outcomes, and the primary safety endpoint is the rate of symptomatic intracranial hemorrhage at 24 hours. Results The first patient was enrolled in the PICASSO Trial on May 8 th , 2024. At the time of submission, 107 patients have been enrolled across 49 active sites in the US. The 101 st patient was enrolled on July 29 th , 2025, thus triggering the first pre‐planned interim analysis after the 90‐day efficacy follow‐up. The analysis will be completed by November 14 th , 2025. The first DSMB meeting, at 50 patients, concluded no safety concerns and to continue the study as designed. Conclusions A comprehensive overview and update on the ongoing PICASSO Trial will be provided at the SVIN Conference assigned session.