AC Immune Presents First In vivo Images of Brain TDP-43 Pathology from Phase 1 Trial of PET tracer ACI-19626, at AD/PDTM 2026

Core Insights - AC Immune SA presented Phase 1 data showcasing the first in vivo images of TDP-43 pathology in the human brain using the PET tracer ACI-19626 at the AD/PD 2026 conference [1][2] Group 1: Clinical Trial Results - Initial data from the Phase 1 trial indicate ACI-19626's potential to detect pathological TDP-43 in patients with TDP-43 proteinopathies, supporting a precision medicine approach for neurodegenerative diseases [2][3] - PET scans revealed significantly higher tracer uptake in key brain regions of patients with frontotemporal dementia (FTD) due to mutated C9orf72 compared to healthy subjects, particularly in subcortical and cortical areas associated with TDP-43 pathology [3][4] - ACI-19626 demonstrated good safety and tolerability, with a dosimetry profile within accepted limits and rapid brain uptake and washout, indicating a suitable pharmacokinetic profile for human brain imaging [3][4] Group 2: Company Outlook and Future Plans - Dr. Andrea Pfeifer, CEO of AC Immune, expressed optimism about ACI-19626's role in early diagnosis of neurodegenerative diseases and highlighted the potential of the company's pipeline for precision prevention [4] - The Phase 1 trial consists of two parts, with Part 1 focusing on healthy volunteers and patients with genetic FTD, expected to complete in H1 2026, while Part 2 may include up to 30 patients with FTD, ALS, or LATE [5] - AC Immune is recognized as a leader in precision prevention for neurodegenerative diseases, with validated technology platforms and a pipeline featuring various therapeutic and diagnostic programs [6]