Axon Neuroscience SE

Headquarters: Bratislava, Slovak Republic Founded: 2010 Type: Clinical-stage biotechnology company Website: axon-neuroscience.eu

Overview

flowchart TD
    companies_axon_neuroscience["Axon Neuroscience SE"]
    style companies_axon_neuroscience fill:#4fc3f7,stroke:#333,color:#000
    companies_axon_neuro_0["Technology Platform"]
    companies_axon_neuroscience -->|"includes"| companies_axon_neuro_0
    style companies_axon_neuro_0 fill:#81c784,stroke:#333,color:#000
    companies_axon_neuro_1["Active Immunotherapy Approach"]
    companies_axon_neuroscience -->|"includes"| companies_axon_neuro_1
    style companies_axon_neuro_1 fill:#ef5350,stroke:#333,color:#000
    companies_axon_neuro_2["Tau Epitope Selection"]
    companies_axon_neuroscience -->|"includes"| companies_axon_neuro_2
    style companies_axon_neuro_2 fill:#ffd54f,stroke:#333,color:#000
    companies_axon_neuro_3["Clinical Pipeline"]
    companies_axon_neuroscience -->|"includes"| companies_axon_neuro_3
    style companies_axon_neuro_3 fill:#ce93d8,stroke:#333,color:#000
    companies_axon_neuro_4["AADvac1  Lead Program"]
    companies_axon_neuroscience -->|"includes"| companies_axon_neuro_4
    style companies_axon_neuro_4 fill:#4fc3f7,stroke:#333,color:#000
    companies_axon_neuro_5["Research Programs"]
    companies_axon_neuroscience -->|"includes"| companies_axon_neuro_5
    style companies_axon_neuro_5 fill:#81c784,stroke:#333,color:#000

Axon Neuroscience SE is a Czech-Slovak biopharmaceutical company dedicated to developing disease-modifying therapeutics targeting tau pathology in Alzheimer’s disease and other neurodegenerative disorders. The company’s lead product, AADvac1, is a novel active immunotherapy (therapeutic vaccine) that stimulates the immune system to produce antibodies against pathological tau proteins. Axon represents one of the most advanced efforts to translate tau immunotherapy from preclinical success to clinical reality

Unlike passive monoclonal antibody approaches, AADvac1 is an active vaccine that generates a polyclonal antibody response against pathological tau. This approach offers potential advantages in terms of durability, cost, and broader epitope coverage. The company is currently evaluating AADvac1 in both Alzheimer’s disease (Phase 2) and as part of the PSP Clinical Trial Platform

Technology Platform

Active Immunotherapy Approach

Axon’s platform is based on therapeutic vaccination — administering tau-derived peptide antigens conjugated to a carrier protein (keyhole limpet hemocyanin, KLH) to stimulate active antibody production in patients:

• Active vs. Passive: Unlike passive monoclonal antibody therapies (e.g., gosuranemab, tilavonemab), active immunotherapy stimulates the patient’s own immune system to produce anti-tau antibodies

• Polyclonal Response: Generated antibodies target multiple epitopes on pathological tau, potentially providing broader coverage than monoclonal approaches

• Durable Effect: Active immunization produces longer-lasting antibody responses, potentially reducing treatment frequency

• Manufacturing Advantage: Peptide-based vaccines are more stable and cost-effective to manufacture than biological antibodies

Tau Epitope Selection

The AADvac1 antigen is designed to selectively target pathological tau while sparing normal physiological tau:

• Targets a specific tau epitope present in aggregated but not normal soluble tau

• The vaccine generates antibodies that preferentially bind to tau aggregates

• Epitope selection minimizes the risk of off-target effects on normal tau function^{3First Alzheimer disease vaccine using tau epitope2016 · Lancet Neurol · DOI 10.1016/S1474-4422(16)30077-8Open reference}

Clinical Pipeline

AADvac1 — Lead Program

AADvac1 (also styled as AADvac1 or AAD-vac1) is Axon’s lead candidate and one of the most advanced active tau immunotherapies in clinical development.

Alzheimer’s Disease (Phase 2 — ADAMANT)

NCT02773758: The ADAMANT study was a randomized, placebo-controlled Phase 2 clinical trial evaluating AADvac1 in patients with mild Alzheimer’s disease^{2AADvac1 Phase 2 results in Alzheimer's disease2022 · Nat Aging · DOI 10.1038/s43587-022-00332-7Open reference}.

Key findings from ADAMANT:

• AADvac1 demonstrated a robust immunogenic response, with high antibody titers in treated patients

• The vaccine showed favorable safety and tolerability profile

• Some evidence of target engagement and biomarker effects

• Cognitive outcomes showed trend toward slowing of decline in predefined subgroup analyses

• The study informed the design of ongoing and future trials

Biomarker evidence: Studies in treated patients showed reduced tau seeding activity in cerebrospinal fluid, suggesting target engagement of pathological tau species^{4Tau seeding activity in brain tissue from AADvac1-treated patients2022 · Acta Neuropathol · DOI 10.1007/s00401-022-02435-6Open reference}.

Progressive Supranuclear Palsy (Phase 2 — PSP Clinical Trial Platform)

AADvac1 has been selected as one of the first investigational products in the PSP Clinical Trial Platform (NCT07173803) at the University of Pennsylvania^{5NCT07173803 - PSP Clinical Trial PlatformOpen reference}:

• The platform trial design allows efficient evaluation of multiple tau-targeting agents

• AADvac1 is being studied in patients with PSP, a pure 4R-tauopathy

• PSP provides a cleaner test environment than AD (no amyloid co-pathology)

• Primary endpoints include safety, biomarker changes, and clinical outcomes (PSPRS)

Rationale for PSP: The absence of amyloid pathology in PSP makes it an ideal setting to test pure tau-targeting approaches. If AADvac1 demonstrates efficacy in PSP, it would support the broader hypothesis that tau immunotherapy can modify disease progression in tauopathies^{6Active tau immunization in 4R-tauopathies2023 · Neurobiol Dis · DOI 10.1016/j.nbd.2023.106000Open reference}.

Research Programs

Axon maintains an active pipeline of next-generation tau immunotherapies:

Scientific Background

Tau Pathology in Neurodegeneration

The tau protein plays essential roles in neuronal cytoskeletal stability under normal conditions. In Alzheimer’s disease, PSP, and related tauopathies, tau becomes hyperphosphorylated, misfolds, and aggregates into toxic species:

• Neurofibrillary tangles (NFTs): Intraneuronal aggregates of hyperphosphorylated tau

• Tau oligomers: Soluble toxic species that propagate between neurons

• Tau filaments: Core components of NFTs, composed of misfolded tau protein

The correlation between tau pathology burden and cognitive decline is stronger than that for amyloid pathology, making tau an attractive therapeutic target^{7Tau immunotherapy: progress and challenges2023 · Nat Rev Neurol · DOI 10.1038/s41582-023-00877-6Open reference}.

Active vs. Passive Immunotherapy

Active tau immunotherapy has several theoretical advantages over passive monoclonal antibodies:

1. Broader epitope coverage: Polyclonal antibodies target multiple tau epitopes simultaneously

2. Durability: Single vaccination can generate long-lasting antibody responses

3. T-cell help: Vaccine-induced antibody responses include T-cell help, potentially enhancing efficacy

4. Cost: Peptide vaccines are less expensive to manufacture than recombinant antibodies

5. 皮下 administration: Potential for less frequent dosing

However, active immunotherapy also has limitations:

• Slower onset of action compared to administered antibodies

• Variable immune responses between patients

• Cannot be rapidly discontinued if adverse events occur

• May be less effective in elderly patients with immunosenescence^{8AADvac1, a novel therapeutic vaccine targeting pathological tau protein2018 · Expert Opin Ther Pat · DOI 10.1080/13543784.2018.1484102Open reference}

Company Profile

Leadership and Team

Axon Neuroscience was founded by leading Slovak neuroscientists with expertise in tau biology and vaccine development:

• The company has assembled a team with deep experience in neurodegenerative disease research

• Clinical operations include partnerships with leading academic centers across Europe and the US

• The company maintains active collaboration with academic institutions for basic research

Intellectual Property

The company holds a broad patent portfolio covering:

• Tau-derived vaccine antigens and formulations

• Methods for producing anti-tau antibodies

• Biomarkers for monitoring treatment response

• Combination therapy approaches

Funding and Partnerships

• Axon has received funding from European research programs and private investors

• Clinical trials have been conducted in partnership with academic medical centers

• The company has explored partnership opportunities with larger pharmaceutical companies for late-stage development

Competitive Landscape

AADvac1 competes in the tau immunotherapy space with both active and passive approaches:

The distinction between active vaccines (AADvac1, ACI-35.030) and passive antibodies is a key differentiator. Active approaches require the patient’s immune system to generate antibodies, while passive approaches deliver antibodies directly.

Therapeutic Targets

• Tau Protein — direct target of AADvac1

• MAPT Gene — gene encoding tau protein

• 4R-Tauopathies — broader disease category

• Progressive Supranuclear Palsy — clinical indication

• Alzheimer’s Disease — clinical indication

• Neurofibrillary Tangles — pathological hallmark

Related Pages

• PSP Clinical Trial Platform

• AADvac1 Active Tau Immunotherapy Trial — if exists

• Tau Immunotherapy Mechanisms — if exists

• 4R-Tau & PSP Therapeutics Pipeline

• AC Immune SA — competitor with tau vaccine ACI-35.030