Abstract Number: Esoc2026lb140 the Role of Mobile Stroke Units in the Fastest Trial

Background and aims Mobile Stroke Units (MSUs) may accelerate enrollment and early trial processes in intracerebral hemorrhage (ICH), but their impact on enrollment efficiency, feasibility, and safety in randomized trials remains incompletely defined. Methods FASTEST was a multicenter randomized trial enrolling patients with spontaneous ICH. In this secondary analysis, patients were categorized as direct MSU enrollment (enrolled entirely on MSU), MSU-facilitated enrollment (identification and initial management on MSU but enrollment in the ED), or non-MSU enrollment. Enrollment efficiency was assessed by time from symptom onset to randomization and by site-level enrollment rates during MSU-available versus MSU-unavailable periods. Issues with MSU enrollment and adverse events were evaluated. Comparisons were conducted using nonparametric tests for continuous variables and χ2 or Fisher's exact tests for categorical variables. Results Among 100 patients enrolled across 13 MSU sites, 38 were enrolled via MSU pathways (17 direct MSU; 21 MSU-facilitated). Median onset-to-randomization time was shorter for MSU-associated enrollments compared with non-MSU enrollments (93 [IQR 26] vs 111.5 [IQR 19] minutes; p<0.001), with a higher proportion enrolled within 90 minutes (36.8% vs 17.7%; p=0.032). Among MSU-associated enrollments, issues were infrequent, with isolated cases of weight estimation error and study kit issues (each 2.6%), with 94.7% having no identified issues. Rates of thromboembolic events did not differ between the two groups. At the site level, enrollment rates during MSU-available periods were higher than during MSU-unavailable periods (0.188 (SD=0.20) vs 0.057 (SD=0.04) enrollments per 10 days), representing a 0.131 relative increase. Conclusions MSUs were associated with faster enrollment, higher enrollment efficiency, and acceptable safety. Conflict of interest