AC Immune presents new Phase 1 data on uptake of ACI-19626

AC Immune (ACIU) SA announced the presentation of new preliminary data from a Phase 1 trial of its first-in-class TDP-43 positron emission tomography tracer ACI-19626 showing increased uptake in the brains of patients with amyotrophic lateral sclerosis. The results presented at the 2026 TDP43 Summit in Madison, Wisconsin, demonstrate that PET scans with ACI-19626 showed tracer uptake significantly higher in key regions of the brain in patients with ALS compared to healthy controls. Specifically, tracer uptake was higher in the brain stem and precentral gyrus, where TDP-43 pathology is expected to accumulate based on post-mortem neuropathology studies and on clinical symptoms. Previously reported data showed significantly higher tracer uptake in disease-relevant subcortical and cortical regions in patients with genetic frontotemporal dementia.