Patients Randomised to Glenzocimab Suffered Less Haemorrhagic Transformation at 24 Hours Compared to Placebo: AI-Imaging Sub-Analysis of the ACTIMIS Trial

Introduction: ACTIMIS (NCT03803007) was a randomized phase 1b/2a clinical trial evaluating glenzocimab, a monoclonal antibody fragment targeting platelet receptor glycoprotein VI, in patients with acute ischemic stroke treated by thrombolysis. In this sub-analysis, volumetric imaging biomarkers were used to assess the efficacy of glenzocimab.

Methods: In the phase 2a study, patients were randomized (1:1) to receive 1000 mg of glenzocimab or a placebo. Baseline and follow-up imaging were processed as a post-hoc analysis using AI core lab software (Brainomix, Oxford, UK), reviewed for accuracy by an expert clinician blinded to treatment allocation.

Results and Conclusions: Follow-up imaging data were available from 103/106 patients (51 glenzocimab, 52 placebo) at 24 hours. Preliminary analysis showed a smaller volume of hemorrhagic transformation (HT) in the glenzocimab group at 24 hours compared to placebo, with a trend toward a smaller volume of ischemic injury. Exploratory analysis also highlighted an interaction effect between the risk of HT following MT and glenzocimab.