Path: /organizations/ac-immune
Type: Biotechnology Company
Headquarters: Lausanne, Switzerland
Founded: 2003
Stock: NASDAQ (ACIU)
AC Immune is a Swiss biotechnology company headquartered in Lausanne, Switzerland, focused on developing novel therapeutics for neurodegenerative diseases, particularly Alzheimer's disease and tauopathies. The company specializes in immunotherapy approaches targeting pathological proteins including tau, amyloid-beta, alpha-synuclein, and TDP-43.
Founded in 2003, AC Immune has established itself as a leader in the field of neurodegenerative disease immunotherapy, with a particular focus on tau-targeting approaches. The company's proprietary SupraAntigen™ technology platform enables the development of highly specific vaccines and antibodies against pathological protein aggregates.
¶ Founding and Early Development
AC Immune was founded in 2003 by Dr. Andrea Pfeifer and Prof. Andreas Muhs, based on research from the Ecole Polytechnique Federale de Lausanne (EPFL). The company's early focus was on developing vaccines against amyloid-beta and tau proteins, recognizing that these pathological proteins were central to neurodegenerative disease pathogenesis.
Key historical milestones:
- 2003: Company founded in Lausanne, Switzerland
- 2006: First partnership with Genentech/Roche
- 2012: SupraAntigen™ platform established
- 2016: ACI-35 tau vaccine enters clinical trials
- 2018: NASDAQ IPO (ACIU)
- 2020: ACI-35 Phase 1b results published
| Program |
Mechanism |
Indication |
Stage |
Partner |
| ACI-35 |
Tau vaccine (phospho-tau) |
Alzheimer's disease |
Phase 2/3 |
Genentech/Roche |
| ACI-35.030 |
Next-gen tau vaccine |
Alzheimer's disease |
Phase 1 |
— |
| ACI-302.24 |
Anti-tau antibody (C-terminal) |
AD/PSP |
Phase 1 |
— |
| ACI-306.01 |
Anti-tau antibody (phospho-specific) |
AD/PSP |
Preclinical |
— |
| Program |
Mechanism |
Indication |
Stage |
Partner |
| ACI-24 |
Amyloid-beta vaccine |
Alzheimer's disease |
Phase 1/2 |
— |
| ACI-24.060 |
Next-gen Aβ vaccine |
Alzheimer's disease |
Phase 1 |
— |
| Anti-Aβ antibodies |
Various |
AD |
Preclinical |
Genentech/Roche |
| Program |
Mechanism |
Indication |
Stage |
| ACI-35.s1 |
α-Syn vaccine |
Parkinson's disease |
Preclinical |
| Anti-α-Syn antibodies |
Passive immunotherapy |
PD/DLB |
Discovery |
| Program |
Mechanism |
Indication |
Stage |
| Anti-TDP-43 antibodies |
Passive immunotherapy |
ALS/FTD |
Discovery |
ACI-35 is a liposome-based vaccine that targets phosphorylated tau (p-tau) at specific epitopes believed to be critical for tau pathology propagation. The vaccine induces antibodies that:
- Recognize pathological tau: Antibodies specifically bind to tau phosphorylated at Ser396 and Ser404, sites implicated in AD progression
- Clear aggregated tau: Antibody binding facilitates microglial phagocytosis of tau aggregates
- Prevent spreading: Antibodies neutralize extracellular tau seeds that propagate pathology between brain regions
Phase 1b Trial (NCT02880982):
- Randomized, placebo-controlled study in 48 patients with mild-to-moderate AD
- Primary endpoint: Safety and tolerability
- Secondary endpoints: Antibody response, cognitive measures
- Results: ACI-35 was well-tolerated with robust IgG antibody response to p-tau
Phase 2/3 Development:
- Currently evaluating in larger AD cohorts
- Primary outcomes: ADAS-Cog, CDR-SB
- Biomarker endpoints: CSF p-tau181, tau PET
Key safety considerations for tau vaccines include:
- ARIA-E: Amyloid-related imaging abnormalities (edema) — monitored via MRI
- Immune response: Robust antibody titers without excessive inflammation
- Off-target effects: Minimal cross-reactivity with normal tau protein
AC Immune's proprietary SupraAntigen™ platform enables the generation of highly specific immunogens:
- Liposome-based delivery: Encapsulation of peptide conjugates in liposomes enhances immune response
- Conformational specificity: Designed to present conformational epitopes unique to aggregated proteins
- Safety profile: Reduced risk of autoimmune responses compared to first-generation vaccines
The platform is applicable to multiple neurodegenerative disease targets:
- Tau: ACI-35, ACI-35.030
- Amyloid-beta: ACI-24 series
- α-Synuclein: α-Syn vaccines
- TDP-43: TDP-43 vaccines
Tau protein pathology follows a characteristic pattern in AD:
- Braak staging: Neurofibrillary tangles spread from entorhinal cortex to limbic system and isocortex
- Correlation with cognition: Tau burden correlates strongly with cognitive impairment
- Therapeutic target: Removing tau pathology may restore neuronal function
Tau immunotherapy represents a promising approach because:
- Tau pathology correlates more directly with cognitive decline than amyloid
- Tau spreads transsynaptically, providing a mechanism for antibody-mediated prevention
- Tau is intracellular, but antibodies can target extracellular tau species that mediate spreading
- Passive and active immunization approaches are both feasible
AC Immune's primary partnership is with Genentech (a Roche company):
Scope:
- ACI-35 global development and commercialization rights
- Amyloid-beta vaccine program
- Anti-tau antibody programs
Financial Terms:
- Upfront and milestone payments
- Royalties on commercial sales
- Co-development in key programs
- Partnership for tau PET tracer development
- Access to novel imaging agents for clinical trials
- Diagnostic complement to therapeutic programs
AC Immune employs biomarker-based patient selection in clinical trials:
- Tau PET: Select patients with elevated tau pathology
- CSF biomarkers: p-tau181, p-tau217 for enrollment
- Amyloid status: Confirm amyloid positivity per AT(N) framework
Phase 2/3 ACI-35 Trial:
- Enrollment: Patients with early AD (MCI due to AD or mild AD dementia)
- Biomarker stratification: Tau PET positive required
- Primary endpoint: Clinical Dementia Rating Scale (CDR)
- Duration: 18-24 months
¶ Competitive Landscape
| Company |
Drug |
Target |
Mechanism |
Status |
| AC Immune |
ACI-35 |
Phospho-tau |
Vaccine |
Phase 2 |
| Eli Lilly |
Donanemab |
Amyloid-beta |
Antibody |
Approved |
| Biogen/Eisai |
Leqembi |
Amyloid-beta |
Antibody |
Approved |
| Biogen |
BIIB080 |
Tau |
ASO |
Phase 1/2 |
| Roche |
Semorinemab |
Tau |
Antibody |
Phase 2 |
| AbbVie |
Etrasimod |
Tau |
Antibody |
Phase 1 |
- Market Cap: ~$300M (as of 2025)
- Cash position: ~$150M
- Cash runway: Through 2026+
- Key investors: Life Sciences Partners, venBio, IDInvest, Bellevue Asset Management
- CEO: Dr. Andrea Pfeifer (co-founder)
- CSO: Dr. Luc P. R. B. van der Haar
- CFO: Dr. Jochen B. W. L. Salm
- CMO: Dr. Cedric W. F. Van der Helling
- CTO: Prof. Andreas Muhs (co-founder)
- Active Immunotherapy: Tau and Aβ vaccines using proprietary SupraAntigen™ platform
- Passive Immunotherapy: Monoclonal antibodies against pathological proteins
- Diagnostic Biomarkers: Tau PET tracers and fluid biomarkers for patient selection
- Combination Approaches: Immunotherapy plus small molecule combinations
While AC Immune focuses primarily on Alzheimer's disease, their tau programs have significant relevance to PSP and other 4R-tauopathies:
- ACI-306.01: Anti-tau antibody targeting p-tau in PSP
- Mechanism: 4R tau aggregation is central to PSP pathology
- Clinical potential: Antibody-based approaches may be applicable to PSP
- Corticobasal Syndrome: Tau pathology responsive to immunotherapy
- FTD with MAPT mutations: Anti-tau approaches may benefit
- Alzheimer's disease with PSP features: Overlapping pathology
See Tau Immunotherapy for mechanism details.
- ACI-35 Phase 2: Evaluating safety and efficacy in early AD
- ACI-35.030 Phase 1: First-in-human for next-generation vaccine
- Biomarker studies: Tau PET, CSF p-tau correlation studies
- ACI-302.24 Phase 1: Anti-tau antibody for AD/PSP
- Combination studies: Vaccine + antibody approaches
AC Immune's science has been published in leading journals:
- ACI-35 Phase 1b results in Alzheimer's and dementia
- Tau immunotherapy mechanisms in Nature Reviews Neurology
- Tau pathology spread in brain
- SupraAntigen platform in Vaccine
¶ Research and Development Facilities
- Primary site: Lausanne, Switzerland (headquarters)
- Research labs: State-of-the-art facilities in Lausanne
- Clinical operations: Global clinical trial management
- Manufacturing: GMP manufacturing capabilities for clinical supply
- 2026: ACI-35 Phase 2 topline data expected
- 2026-2027: Initiate Phase 3 if Phase 2 successful
- 2027: Potential BLA/MAA filing
- Additional tau programs in PSP
- α-Syn programs advancing to IND
- TDP-43 programs in preclinical development