AC Immune's stock experienced a significant surge after announcing positive interim data from its Phase II VacSYn trial (NCT06015841) of ACI-7104.056, an anti-alpha-synuclein (a-syn) active immunotherapy candidate for Parkinson's disease. The Switzerland-based pharmaceutical company witnessed its stock price jump by 26.9% following the announcement.
Immunogenicity and Antibody Response
The interim data revealed that all patients in the trial responded to the target antigen, with strongly boostable antibody responses observed at six weeks. Alpha-synuclein is a key protein implicated in Parkinson's disease due to its high prevalence in affected patients. Treatment with ACI-7104.056 led to an average 16-fold increase in anti-a-syn antibodies compared to placebo levels after three immunizations.
Management Commentary
Dr. Andrea Pfeifer, CEO of AC Immune, stated, "The level of immunogenicity after only three months of treatment, as well as the continued positive safety profile, reinforces the best-in-class characteristics of our clinically validated anti-a-syn active immunotherapy for the treatment of Parkinson’s disease."
Trial Design and Safety
The VacSYn trial is an adaptive, placebo-controlled, biomarker-based Phase II study in patients with early Parkinson’s disease. Part 1 included initial analyses from over 30 patients randomized to receive ACI-7104.056 or placebo at a 3:1 ratio. The safety profile was favorable, with only transient injection site reactions (49%) and headaches (18%) reported as adverse events.
Future Plans
AC Immune intends to release further interim results in H1 2025, including pharmacodynamic data, after which it plans to initiate Part 2 of the VacSYn trial with up to 150 patients. Part 2 will evaluate the progression of motor and non-motor symptoms, as well as digital, imaging, and fluid biomarkers. The company hopes that data from the second part of the study will support progression to a pivotal study.
Competitive Landscape
According to GlobalData’s drug database, there are 93 pipeline products in Phase I to Phase III development within the 7MM for the treatment of Parkinson’s disease. Therapies targeting a-syn aggregation account for 26% of the pipeline disease-modifying therapies (DMTs). Vaxxinity announced positive data from a Phase I trial of its a-syn vaccine-like therapy, UB-312, at the AD/PD conference in March 2024.
