AC Immune SA reported promising interim results from its Phase 2 VacSYn clinical trial evaluating ACI-7104.056, an anti-alpha-synuclein active immunotherapy for early Parkinson's disease, demonstrating strong immunogenicity and a favorable safety profile. The Swiss biopharmaceutical company announced these developments alongside its second quarter 2025 financial results on August 5, 2025.
Strong Immunogenic Response in Parkinson's Disease Trial
The interim data from the VacSYn trial showed that treatment with ACI-7104.056 induced an average 20-fold increase in anti-alpha-synuclein antibodies after four immunizations compared to placebo background levels. This wholly owned active immunotherapy candidate reinforced what the company describes as "best-in-class characteristics" in treating patients with early Parkinson's disease.
Dr. Andrea Pfeifer, CEO of AC Immune SA, commented: "Interim results on ACI-7104.056, our wholly owned a-syn active immunotherapy, reinforced its best-in-class characteristics, showing strong immunogenicity and a favorable safety profile in early Parkinson's disease."
Based on pharmacodynamic and biomarker interim results expected later in 2025, AC Immune may decide to initiate Part 2 of VacSYn, with the aim of establishing early proof-of-concept and identification of disease-specific biomarkers for rapid transition into a pivotal study.
Comprehensive Pipeline Progress
AC Immune is advancing three active immunotherapies through Phase 2 clinical development for precision prevention of neurodegeneration. Beyond ACI-7104.056, the company's partnered programs ACI-24.060 and ACI-35.030 are progressing according to plan.
The third Alzheimer's disease cohort (AD3) in the Phase 2 ABATE trial of anti-Abeta ACI-24.060 is expected to reach 12 months of treatment in December 2025, with interim results anticipated in early 2026.
Early-Stage Pipeline Advancement
The company's small molecule NLRP3 program has entered IND-enabling studies, highlighting promise in the early-stage pipeline. ACI-19764, a novel Morphomer small molecule inhibitor of NLRP3, has now entered studies to enable an Investigational New Drug (IND) filing, which is expected in H2 2025.
AC Immune's therapeutic and diagnostic programs were featured in multiple presentations at AD/PD 2025, where the company hosted an industry symposium highlighting its pipeline of active immunotherapies for precision prevention of neurodegenerative diseases.
Financial Position and Outlook
The company maintains a strong financial position with cash resources of CHF 127.1 million (USD 157.6 million) as of June 30, 2025, providing funding into Q1 2027 excluding any potential milestone payments. This represents a decrease from CHF 165.5 million as of December 31, 2024.
For the second quarter 2025, AC Immune recorded CHF 1.3 million in contract revenues compared to CHF 0.7 million in the comparable prior period. Research and development expenses were CHF 16.8 million compared to CHF 17.1 million in the comparable period in 2024. The company reported a net loss after taxes of CHF 21.2 million for the three months ended June 30, 2025, compared with a net loss of CHF 22.8 million for the comparable period in 2024.
Upcoming Clinical Milestones
AC Immune has outlined multiple anticipated milestones for H2 2025, including interim pharmacodynamic and biomarker results from Part 1 of the Phase 2 VacSYn trial, the IND filing for ACI-19764, and Phase 1 readouts for both TDP-43-PET tracer and ACI-15916 alpha-synuclein-PET tracer in Parkinson's disease.
The company's two clinically validated technology platforms, SupraAntigen and Morphomer, continue to fuel its pipeline of therapeutic and diagnostic programs, which currently features candidates in Phase 2 and Phase 3 development. AC Immune has secured strategic partnerships with leading global pharmaceutical companies, resulting in over $4.5 billion in potential milestone payments plus royalties.
