• ACI-7104.056 active immunotherapy demonstrated strong immunogenicity in early Parkinson's disease patients, producing anti-alpha-synuclein antibody levels 20-fold higher than placebo after four immunizations.
• The Phase 2 VacSYn trial showed repeated immunizations successfully amplified antibody response, with no serious adverse events reported and only mild injection site reactions and headaches as common side effects.
• AC Immune may expand the trial to include 150 additional patients later in 2025, with plans to evaluate disease progression markers and establish proof-of-concept for this potential first-in-class treatment approach.