AC Immune Trial Shows Early Signs Immunotherapy May Slow Parkinson's

Core Insights - AC Immune SA has released interim results from the Phase 2 VacSYn trial for its anti-alpha-synuclein immunotherapy ACI-7104.056, indicating potential disease modification in early Parkinson's disease [1][2] - The results show stabilization of disease-related biomarkers, suggesting a slowing of neuronal damage and progression of Parkinson's disease [2][3] Biomarker Results - Elevated levels of neurofilament light (NfL) are associated with neuronal damage; stabilization of NfL levels indicates a potential slowing of neurodegeneration [2] - Plasma glial fibrillary acidic protein (GFAP) and dopamine transporter (DaT) SPECT imaging trends also suggest disease modification [3] Antibody Response - ACI-7104.056 demonstrated a 100% responder rate in generating antibodies against the a-syn target antigen, with serum antibody titers over 500-fold higher than the placebo group at week 76 [3][4] - Antibody responses were boosted with each immunization, and average IgG antibody levels in cerebrospinal fluid (CSF) were also over 500-fold higher than in the placebo group [4] Clinical Measures - Clinical measures of motor symptoms indicate a trend toward stabilization in the active treatment group, with no meaningful progression in the MDS-UPDRS Part III score compared to an expected increase in the placebo group [5][6] - The difference in change from baseline scores between the active treatment and placebo groups was enhanced when stratified by levodopa (L-DOPA) ON/OFF state [6] Safety and Tolerability - Interim results from weeks 50 and 76 show that ACI-7104.056 is generally safe and well-tolerated [6] - Final data from Part 1 of the VacSYn trial are anticipated in mid-2026 [6] Market Reaction - Following the announcement, AC Immune's stock price increased by 12.43%, reaching $3.14 [6]