Abstract TP368: Relevance of Lesion Volume as an Outcome in Cerebral Cavernous Malformation Drug Trial

Background: It is not clear if changes in lesion volume might represent a clinically relevant and statistically advantageous outcome parameter in early phase trials of novel drugs aimed at preventing bleeding in cerebral cavernous malformations (CCM). Methods: We analyzed the modified intention to treat cohort (33 patients receiving atorvastatin and 31 placebo) who contributed at least one paired imaging biomarker in the recently completed double-blinded randomized controlled AT CASH EPOC trial (clinicaltrials.gov NCT02603328). We examined prospective changes in CCM lesion volume and correlated these with symptomatic hemorrhage (SH) events. We contemporaneously assessed changes in lesional iron content by quantitative susceptibility mapping (QSM) on MRI, and objective (mRS) and subjective (EQ-VAS) functional status. We also simulated sample sizes needed to detect potential effects of a drug on lesion volume. Results: There was excellent correlation between independently assessed maximum lesion diameter and CCM lesion volume (R 2 = 0.68, P