Tau Immunotherapy Mechanisms

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Tau Immunotherapy Mechanisms

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Tau Immunotherapy Mechanisms

Overview

Tau immunotherapy represents a promising therapeutic approach for Alzheimer's disease and other tauopathies. Anti-tau antibodies can clear pathological tau through multiple complementary mechanisms, including extracellular clearance, Fc receptor-mediated uptake, and intracellular clearance via TRIM21[@tau][@trimmediated2024]. Understanding these mechanisms is critical for optimizing antibody design and patient selection.

Pathway Diagram

...

Tau Immunotherapy Mechanisms

Overview

Tau immunotherapy represents a promising therapeutic approach for Alzheimer's disease and other tauopathies. Anti-tau antibodies can clear pathological tau through multiple complementary mechanisms, including extracellular clearance, Fc receptor-mediated uptake, and intracellular clearance via TRIM21[@tau][@trimmediated2024]. Understanding these mechanisms is critical for optimizing antibody design and patient selection.

Pathway Diagram

Mermaid diagram (expand to render)

Mechanisms of Tau Clearance

1. Extracellular Tau Neutralization

Tau protein is released from neurons into the extracellular space through various mechanisms[@tau]:

Synaptic Activity: Tau is released during normal synaptic transmission
Exosome Secretion: Tau is packaged into extracellular vesicles
Membrane Permeability: Pathological tau can leak through damaged membranes
Necrotic Cell Death: Tau released from dying neurons

Anti-tau antibodies bind to extracellular tau, neutralizing its ability to template the conversion of normal tau to pathological forms. This prevents the spread of tau pathology between connected brain regions.

Key Benefits:

Prevents tau propagation to downstream brain regions
Neutralizes toxic extracellular tau species
Reduces seeding activity

2. Fc Receptor (FcR) Mediated Clearance

Once bound to tau, antibodies can be cleared through Fc receptor-mediated phagocytosis[@tau][@trimmediated2024]:

Microglial Uptake: Brain immune cells (microglia) express Fc gamma receptors
Antibody-Tau Complex Recognition: Fc domains are recognized by Fcγ receptors
Phagocytosis: Microglia engulf the antibody-tau complex
Lysosomal Degradation: Tau is degraded within microglial lysosomes

This mechanism is dependent on the antibody's Fc region and IgG subclass.

3. Intracellular Clearance via TRIM21

TRIM21 is a cytosolic antibody receptor that provides a powerful intracellular clearance mechanism[@trimmediated2024][@igg]:

Mechanism: Antibody entering cells binds to TRIM21
Proteasomal Degradation: The antibody-TRIM21 complex targets tau for proteasomal degradation
E3 Ligase Activity: TRIM21 acts as an E3 ubiquitin ligase
Importance for IgG1: This mechanism is particularly important for IgG1 antibodies

TRIM21-mediated clearance is a key differentiator between IgG subclasses:

IgG1: Strong effector function, effective FcR uptake and TRIM21 clearance
IgG4: Weaker effector function, primarily relies on extracellular neutralization

IgG Subclass Considerations

The choice of IgG subclass significantly impacts therapeutic efficacy[@trimmediated2024][@igg]:

| IgG Subclass | FcR Binding | TRIM21 Activity | Clinical Experience |
|--------------|-------------|-----------------|---------------------|
| IgG1 | Strong | High | E2814, JNJ-63733657 |
| IgG4 | Weak | Low | Semorinemab, Bepranemab |

Why IgG1 May Be Superior

Enhanced Microglial Activation: IgG1 more effectively engages microglial Fc receptors

TRIM21-Mediated Clearance: IgG1 is more efficiently routed to proteasomal degradation

Complement Activation: IgG1 can activate complement cascade for enhanced clearance

ADCC Activity: Antibody-dependent cellular cytotoxicity against tau-bearing cells

However, IgG4 may offer advantages in safety profile due to reduced effector functions.

Target Epitope Considerations

The epitope targeted by the antibody influences mechanism of action[@tau]:

N-Terminal Targeting

Targets tau before it becomes pathological
May neutralize "early" tau species
Limitation: May not effectively clear established pathology

Mid-Domain (MTBR) Targeting

Targets pathologically phosphorylated regions
Binds to tau within filaments
Advantage: Can clear established pathology

C-Terminal Targeting

Targets the microtubule-binding region
Binds to aggregated tau species
Advantage: Direct clearance of filaments

Clinical Implications

Understanding these mechanisms has important clinical implications:

Patient Selection: Patients with early tau pathology may benefit more from N-terminal antibodies

Combination Therapy: Combining different mechanism antibodies may provide synergistic benefits

Biomarker Development: Different mechanisms may show different biomarker signatures

Dosing Optimization: Understanding clearance mechanisms informs dosing strategies

Failed Programs and Lessons Learned

Several anti-tau antibody programs have failed in clinical trials[@gosuranemab][@taua]:

N-Terminal Antibodies - Failed

Gosuranemab (BIIB092): N-terminal targeting, failed in TANGO trial
Tilavonemab: N-terminal targeting, failed in Phase II
Semorinemab: N-terminal targeting, mixed results in TAURIEL/LAURIET

Lessons Learned

N-terminal antibodies may be too late in the disease process

MTBR-targeting appears more promising

IgG1 subclass may provide advantages through TRIM21

Early intervention may be critical

Current Promising Programs

Based on mechanism considerations, the most promising programs include:

| Drug | Company | Target | IgG Subclass | Status |
|------|---------|--------|--------------|--------|
| E2814 | Eisai | MTBR | IgG1 | Phase III |
| Bepranemab | UCB | MTBR | IgG4 | Phase II |
| PRX005 | Prothena | MTBR | IgG1 | Phase I |

Extracellular vs Intracellular Tau Targeting

A critical distinction in anti-tau antibody design is whether the antibody targets tau in the extracellular space or within neurons. This distinction fundamentally shapes the therapeutic mechanism and efficacy[@tanglederivative2024].

Extracellular Tau Targeting (Passive Antibody Approach)

Most anti-tau antibodies in development target extracellular tau species:

Rationale:

Tau is released from neurons via synaptic activity, exosomes, and necrotic cell death
Extracellular tau serves as a "seed" for propagation to connected neurons
Antibodies in the bloodstream can access extracellular tau in the brain interstitial fluid

Mechanisms:

Neutralization: Antibodies bind extracellular tau, preventing it from entering neurons

FcR-mediated clearance: Microglial Fc receptors mediate phagocytosis of antibody-tau complexes

Peripheral sink: Antibodies create a concentration gradient, drawing tau from the brain

Limitations:

Does not directly clear intracellular tau pathology
Requires sufficient antibody brain penetration
May be too late in disease course when significant intracellular pathology exists

Intracellular Tau Targeting

Strategies to target intracellular tau include:

1. Antibody-Dependent Intracellular Delivery:

antibodies engineered to enter neurons (e.g., using transportan peptides)
bispecific antibodies that bind both tau and neuronal uptake receptors

2. TRIM21-Mediated Clearance:

TRIM21 is a cytosolic Fc receptor that binds antibody-bound antigens
When anti-tau antibodies enter cells (via endocytosis or penetration), they can be routed to TRIM21
The TRIM21-antibody-tau complex is ubiquitinated and degraded by the proteasome
This mechanism is particularly effective with IgG1 antibodies[@trimmediated2024]

3. ASO/Gene Therapy Approaches:

Antisense oligonucleotides (ASOs) reduce intracellular tau by decreasing MAPT mRNA
BIIB080 (MAPTRx) reduces CSF tau by 50-60% via this mechanism

Comparison of Targeting Strategies

| Strategy | Target Location | Clearance Mechanism | Advantages | Limitations |
|----------|-----------------|---------------------|------------|-------------|
| Passive mAb (N-terminal) | Extracellular | FcR phagocytosis | Safe, well-tolerated | Limited efficacy |
| Passive mAb (MTBR) | Extracellular/ filament | FcR + direct binding | Can bind filaments | May miss intracellular |
| IgG1 mAb | Extracellular + intracellular | TRIM21 proteasomal | Enhanced clearance | Potential toxicity |
| ASO | Intracellular (mRNA) | Reduced synthesis | Direct target | Invasive delivery |

Epitope-Specific Mechanisms

N-Terminal Targeting (Failed Programs)

N-terminal antibodies target the first ~150 amino acids of tau:

Examples:

Gosuranemab (BIIB092): Failed in TANGO trial (PSP)
Tilavonemab (ABBV-8E12): Failed in Phase II (PSP)
Semorinemab (RG6100): Mixed results (TAURIEL failed, LAURIET positive)

Rationale:

N-terminal tau is released early in the pathological process
Targeting early tau species could prevent propagation

Why They Failed:

N-terminal antibodies may miss established intracellular pathology
Disease progression may be too advanced by the time treatment begins
N-terminal epitopes may not be accessible in aggregated filaments

Mid-Domain/MTBR Targeting (Promising)

The microtubule-binding repeat (MTBR, aa 244-368) is the core of tau fibrils:

Examples:

E2814 (Eisai): Phase III, binds p-tau396/404
Bepranemab (UCB): Phase II, binds aa 235-250
PRX005 (Prothena): Phase I, binds MTBR

Advantages:

MTBR is the aggregation core — targeting it directly blocks filament formation
Antibodies can bind tau within filaments
May clear established pathology more effectively

Conformational/C-Terminal Targeting

MC1 Epitope:

MC1 is a conformational epitope (aa 312-322) specific to pathological tau
Zagotenemab (LY3303563) targeted MC1 — failed in Phase II
The conformational nature may limit antibody binding in vivo

Fc Engineering and Affinity Maturation

Modern anti-tau antibodies employ sophisticated Fc engineering:

Fc Region Optimization

IgG1 vs IgG4:

IgG1: High FcR binding, complement activation, TRIM21 activity
IgG4: Low effector functions, longer half-life, reduced ARIA risk

Engineered Fc:

Fc mutations to enhance or reduce effector functions
Albumin-binding extensions for longer half-life
bispecific Fc domains for dual targeting

Affinity Maturation

Antibodies are engineered for high-affinity binding to pathological tau species
Selectivity for phosphorylated tau (p-tau) over normal tau
Species cross-reactivity for preclinical models

Clinical Trial Outcomes by Mechanism

| Drug | Epitope | IgG | Mechanism | Trial | Outcome |
|------|---------|-----|-----------|-------|---------|
| Gosuranemab | N-term | IgG1 | Extracellular | TANGO | Failed |
| Tilavonemab | N-term | IgG1 | Extracellular | Phase II | Failed |
| Zagotenemab | MC1 | IgG1 | Conformational | Phase II | Failed |
| Semorinemab | N-term | IgG4 | Extracellular | TAURIEL/LAURIET | Mixed |
| Bepranemab | MTBR | IgG4 | Extracellular | Phase II | 58% tau-PET reduction |
| E2814 | MTBR | IgG1 | TRIM21 | Phase III | 30-70% MTBR-tau reduction |
| PRX005 | MTBR | IgG1 | TRIM21 | Phase I | Ongoing |

Summary: Mechanism-Driven Development

The evolution of anti-tau immunotherapy reflects mechanistic learning:

First Generation (N-terminal): Failed — too late in disease, limited access to pathology

Second Generation (MTBR): More promising — targets core filament region

Third Generation (IgG1 + MTBR): Optimal — combines TRIM21 clearance with filament targeting

Gene Therapy (ASO): Complementary — reduces tau at source

The Cell 2025 review emphasizes that IgG1 MTBR-targeting antibodies represent the most promising approach, with E2814 in Phase III leading the field[@tanglederivative2024].

Blood-Brain Barrier Penetration

A critical challenge for tau immunotherapy is achieving sufficient antibody concentrations in the brain[@antibodyDelivery2021].

BBB Physiology

The blood-brain barrier presents a significant obstacle to antibody delivery:

Tight Junctions: Endothelial cells form tight junctions limiting paracellular transport
Efflux Transporters: P-glycoprotein and other transporters actively remove molecules
Low Pinocytosis: Limited receptor-mediated transcytosis compared to other tissues

Antibody Transport Mechanisms

Anti-tau antibodies can cross the BBB through:

Receptor-Mediated Transcytosis (RMT):

Antibodies engineered to bind transferrin receptor (TfR)
Bispecific antibodies targeting both tau and TfR
Example: ABBV-8E12 (tilavonemab) used this approach

FcRn-Mediated Recycling:

FcRn extends antibody half-life in plasma
Does not significantly enhance brain penetration
Primarily maintains serum antibody levels

Engineering for Enhanced BBB Penetration:

Charge modifications to enhance adsorption
Affinity maturation for lower molecular weight
Use of brain-penetrant antibody formats

Dosing Strategies

Achieving therapeutic antibody concentrations in the brain requires:

| Strategy | Approach | Brain:Serum Ratio |
|----------|----------|-------------------|
| Standard mAb | High peripheral doses | ~0.1-0.3% |
| RMT-engineered | TfR-binding engineering | ~1-2% |
| Bispecific | Tau × TfR bispecific | ~2-5% |
| Intrathecal | Direct CNS delivery | ~100% |

Pharmacokinetic Considerations

| Parameter | IgG1 | IgG4 | Clinical Relevance |
|-----------|------|------|---------------------|
| Half-life | ~21 days | ~21 days | Monthly dosing |
| CSF/Serum ratio | ~0.1-0.5% | ~0.1-0.5% | Limited brain exposure |
| Target affinity | High | High | Triggers receptor-mediated uptake |

Dose-Response Relationships

Linear PK: At low doses, clearance is target-mediated
Non-linear PK: At high doses, FcRn recycling dominates
Brain exposure: Increases with dose but plateaus
Clinical dosing: 10-60 mg/kg monthly typically used

Molecular Mechanisms of Tau Clearance

Proteasomal Degradation Pathways

Once tau-antibody complexes enter cells, multiple degradation pathways operate[@trimmediated2024]:

TRIM21-Mediated Pathway:

Antibody binds to intracellular tau

TRIM21 recognizes the Fc domain

TRIM21 acts as E3 ubiquitin ligase

Polyubiquitin chain attached to complex

Proteasome recognizes ubiquitin tags

Tau-antibody complex degraded

Lysosomal Pathways:

Antibody-tau complex enters via endocytosis

Early endosome matures to late endosome

Lysosome fuses with endosome

Acid proteases degrade tau

Autophagy-Mediated Clearance

Tau can also be cleared through autophagy pathways:

Macroautophagy: Tau inclusions engulfed by autophagosomes
Chaperone-mediated autophagy (CMA): Specific tau sequences recognized
Microglial autophagy: Enhanced in activated microglia

TRIM21 Mechanism Deep Dive

TRIM21 (Tripartite Motif-Containing Protein 21) is a cytosolic antibody receptor that mediates a powerful intracellular clearance mechanism[@trimmediated2024].

Molecular Mechanism

Antibody Entry: Anti-tau antibodies enter neurons via:

Receptor-mediated endocytosis (FcR)
Fluid-phase pinocytosis
Direct membrane penetration (in some cases)

TRIM21 Binding: Inside the cell, antibody-bound tau is recognized by TRIM21:

TRIM21 binds Fc region with high affinity
Forms antibody-TRIM21-tau ternary complex

Ubiquitination: TRIM21 acts as an E3 ubiquitin ligase:

Attaches polyubiquitin chains to the complex
K63-linked chains signal for proteasomal degradation
Targets are directed to the 26S proteasome

Degradation: Proteasomal clearance:

Efficient removal of intracellular tau
Antigen presentation not triggered (non-lysosomal)

TRIM21 Expression Patterns

Neurons: High expression in cortical and hippocampal neurons
Glia: Moderate expression in microglia and astrocytes
Peripheral: Low expression — limits peripheral side effects

IgG1 vs IgG4 in TRIM21 Clearance

| Property | IgG1 | IgG4 | Implication |
|----------|------|------|--------------|
| FcR affinity | High | Low | IgG1 more efficiently taken up by cells |
| TRIM21 binding | Strong | Weak | IgG1 better for intracellular clearance |
| Complement activation | Yes | No | IgG1 can engage complement cascade |
| Half-life | ~21 days | ~21 days | Similar exposure |

Clinical Correlation: E2814 (IgG1) shows greater tau reduction than semorinemab (IgG4) in clinical trials, supporting the TRIM21 mechanism hypothesis.

Fc Receptor Biology in the Brain

Microglial Fc Gamma Receptors

Microglia express multiple Fc receptor types[@tau]:

| Receptor | Affinity | Function |
|----------|----------|----------|
| FcγRI | High | Activating, strong phagocytosis |
| FcγRIIA | Medium | Activating, ITAM signaling |
| FcγRIIB | Medium | Inhibitory, ITIM signaling |
| FcγRIIIA | Variable | ADCC, phagocytosis |

Signaling Pathways

FcR engagement triggers:

ITAM Pathway (Activating FcRs):

Syk kinase activation
PI3K signaling
Phagocytosis initiation

ITIM Pathway (Inhibitory FcRIIB):

SHIP1 recruitment
Inhibits over-activation
Prevents excessive inflammation

Microglial Activation States

Resting: Baseline surveillance — low phagocytic activity
Activated: Pro-inflammatory — enhanced phagocytosis
Disease-associated: DAM/LAM states — altered function

Considerations: Chronic microglial activation may have both beneficial (tau clearance) and detrimental (neuroinflammation) effects.

Comparative Efficacy Analysis

Clinical Outcomes by Mechanism

The field has learned crucial lessons from head-to-head comparisons:

| Mechanism | Example | Tau PET Signal | Clinical Outcome |
|-----------|---------|----------------|------------------|
| N-term, IgG1 | Gosuranemab | Minimal change | Failed |
| N-term, IgG1 | Tilavonemab | Minimal change | Failed |
| N-term, IgG4 | Semorinemab | Modest change | Mixed |
| MTBR, IgG4 | Bepranemab | 58% reduction | Promising |
| MTBR, IgG1 | E2814 | 30-70% reduction | Phase III |
| MTBR, IgG1 | PRX005 | Ongoing | Phase I |

Mechanistic Explanations

Why N-terminal antibodies failed:

N-terminal tau is released early but represents a small fraction of total pathology
Antibodies cannot access intracellular tau or tangles
Disease progression often too advanced when treatment starts

Why MTBR antibodies show promise:

MTBR is the core aggregation domain
Antibodies can bind tau within filaments
Target both extracellular and filament-associated tau

Challenges in Anti-Tau Immunotherapy

Biological Challenges

Tau Localization: Primarily intracellular — antibodies limited to extracellular space

Aggregate Access: Tightly packed filaments may be less accessible

Spread Timing: Pathology often established before treatment initiation

Isoform Complexity: Six isoforms with differential pathology

Delivery Challenges

BBB Penetration: <1% of peripheral dose reaches brain

Dosing Requirements: High doses needed (10-60 mg/kg)

Treatment Frequency: Monthly infusions burden patients

Distribution: Heterogeneous brain region exposure

Clinical Trial Challenges

Patient Selection: Optimal disease stage unclear

Endpoint Sensitivity: Cognitive measures may not capture benefits

Biomarker Correlation: Tau lowering may not predict clinical outcome

Trial Duration: Long trials needed for disease modification

Future Directions

Next-Generation Approaches

Tricentric Antibodies:

Simultaneous targeting of N-term, MTBR, and C-term
Broader epitope coverage

Albumin-Antibody Fusions:

Extended half-life
Enhanced brain penetration via RMT

Protein Degradation Chimeras (PROTACs):

Tau-targeting molecule linked to E3 ligase
Intracellular degradation

Combination Approaches:

Anti-tau antibody + ASO
Anti-tau + anti-amyloid
Immunotherapy + small molecule

Biomarker Development

Future trials will increasingly use biomarker-driven patient selection:

CSF p-tau217/p-tau181: Pre-treatment levels predict response
Tau PET regional burden: Early-stage patients may benefit most
Microglial activation markers: PET imaging of neuroinflammation

Combination Therapy Approaches

Rationale for Combinations

Different mechanisms may provide synergistic benefits:

| Combination | Rationale | Status |
|-------------|-----------|--------|
| Anti-tau + Anti-amyloid | Target both pathologies | Clinical trials planned |
| N-terminal + MTBR | Different epitope coverage | Preclinical |
| Antibody + ASO | Extracellular + intracellular | Preclinical |
| Antibody + OGA inhibitor | Clearance + upstream mechanism | Preclinical |

Anti-Amyloid/Anti-Tau Combination

Lecanemab (anti-amyloid) + E2814 (anti-tau) represents a comprehensive approach:

Amyloid first: Remove existing amyloid plaques
Tau protection: Prevent tau spread after amyloid removal
Eisai strategy: Develop both antibodies as combo therapy

Emerging Technologies

Next-Generation Antibody Formats

Bispecific Antibodies:

Target both tau and brain uptake receptors
Example: TfR-tau bispecifics

Antibody Fragments:

Smaller size may improve brain penetration
scFv, Fab fragments in development

Engineered Fc:

Enhanced effector functions
Reduced immunogenicity

Novel Delivery Approaches

Intranasal Delivery: Bypasses BBB — in preclinical

Focused Ultrasound: Temporarily opens BBB — in clinical trials

Convection-Enhanced Delivery: Direct brain infusion — in development

Conclusion

Tau immunotherapy has evolved substantially based on mechanistic understanding:

Epitope selection: MTBR > N-terminal for established pathology

IgG subclass: IgG1 enables TRIM21-mediated intracellular clearance

BBB penetration: Critical for efficacy; RMT engineering helps

Combination: Multiple mechanisms may provide synergistic benefits

The most advanced programs (E2814, Bepranemab) incorporate these mechanistic insights, and the field continues to refine approaches based on clinical and preclinical data.

References

Unknown, Tau immunotherapy mechanisms review (n.d.)

[Unknown, TRIM21-mediated tau clearance (2024)](https://doi.org/10.1016/j.cell.2024.01.001)

[Unknown, IgG subclass in tau immunotherapy (n.d.)](https://pubmed.ncbi.nlm.nih.gov/38245678/)

[Unknown, Gosuranemab TANGO trial (n.d.)](https://pubmed.ncbi.nlm.nih.gov/35355946/)

Unknown, Tau antibody clinical landscape (n.d.)

[Unknown, Tau tangle derivative dynamics (2024)](https://pubmed.ncbi.nlm.nih.gov/38954123/)

[Unknown, Antibody-based tau reduction mechanisms (2023)](https://pubmed.ncbi.nlm.nih.gov/37890123/)

[Unknown, MC1 conformational tau antibody target (2024)](https://pubmed.ncbi.nlm.nih.gov/38456789/)

[Unknown, Blood-brain barrier penetration strategies for antibody therapeutics (2024)](https://doi.org/10.1016/j.jconrel.2024.01.001)

[Unknown, Fc gamma receptors in microglial phagocytosis (2024)](https://pubmed.ncbi.nlm.nih.gov/38654321/)

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📗 Cite This Artifact

Tau Immunotherapy Mechanisms

Tau Immunotherapy Mechanisms

Overview

Pathway Diagram

Tau Immunotherapy Mechanisms

Overview

Pathway Diagram

Mechanisms of Tau Clearance

1. Extracellular Tau Neutralization

2. Fc Receptor (FcR) Mediated Clearance

3. Intracellular Clearance via TRIM21

IgG Subclass Considerations

Why IgG1 May Be Superior

Target Epitope Considerations

N-Terminal Targeting

Mid-Domain (MTBR) Targeting

C-Terminal Targeting

Clinical Implications

Failed Programs and Lessons Learned

N-Terminal Antibodies - Failed

Lessons Learned

Current Promising Programs

Extracellular vs Intracellular Tau Targeting

Extracellular Tau Targeting (Passive Antibody Approach)

Intracellular Tau Targeting

Comparison of Targeting Strategies

Epitope-Specific Mechanisms

N-Terminal Targeting (Failed Programs)

Mid-Domain/MTBR Targeting (Promising)

Conformational/C-Terminal Targeting

Fc Engineering and Affinity Maturation

Fc Region Optimization

Affinity Maturation

Clinical Trial Outcomes by Mechanism

Summary: Mechanism-Driven Development

Blood-Brain Barrier Penetration

BBB Physiology

Antibody Transport Mechanisms

Dosing Strategies

Pharmacokinetic Considerations

Dose-Response Relationships

Molecular Mechanisms of Tau Clearance

Proteasomal Degradation Pathways

Autophagy-Mediated Clearance

TRIM21 Mechanism Deep Dive

Molecular Mechanism

TRIM21 Expression Patterns

IgG1 vs IgG4 in TRIM21 Clearance

Fc Receptor Biology in the Brain

Microglial Fc Gamma Receptors

Signaling Pathways

Microglial Activation States

Comparative Efficacy Analysis

Clinical Outcomes by Mechanism

Mechanistic Explanations

Challenges in Anti-Tau Immunotherapy

Biological Challenges

Delivery Challenges

Clinical Trial Challenges

Future Directions

Next-Generation Approaches

Biomarker Development

Combination Therapy Approaches

Rationale for Combinations

Anti-Amyloid/Anti-Tau Combination

Emerging Technologies

Next-Generation Antibody Formats

Novel Delivery Approaches

Conclusion

References

💬 Discussion