This page provides a comprehensive comparison of monoclonal antibodies targeting amyloid-beta (anti-amyloid) and tau protein (anti-tau) in Alzheimer's disease and related neurodegenerative disorders. These disease-modifying therapies represent the cutting edge of Alzheimer's treatment with three anti-amyloid antibodies now FDA-approved and multiple anti-tau antibodies in clinical development.
| Property |
Details |
| Developer |
Eisai/Biogen |
| Target |
Soluble Aβ protofibrils |
| Mechanism |
Selectively binds soluble Aβ protofibrils with ~10-fold higher affinity than monomers, 1000-fold higher than plaques |
| FDA Status |
Full approval (2023) |
| Phase 3 Trial |
CLARITY-AD |
| Clinical Endpoint |
27% slowing of decline on CDR-SB at 18 months |
| CDR-SB Change |
1.21 vs 1.66 (placebo), difference = 0.45 (p<0.001) |
| Amyloid PET Reduction |
55.5 centiloids at 18 months |
| Plasma p-tau217 |
23% decrease from baseline |
| Dosing |
Bi-weekly IV infusion (10 mg/kg) |
| ARIA-E Rate |
12.6% (vs 1.7% placebo) |
| ARIA-H Rate |
17.3% (vs 8.7% placebo) |
| Property |
Details |
| Developer |
Eli Lilly |
| Target |
Pyroglutamate-modified Aβ (pE3-Aβ) |
| Mechanism |
Targets highly aggregation-prone species found in plaques; enhanced Fc-mediated effector function |
| FDA Status |
Full approval (2024) |
| Phase 3 Trial |
TRAILBLAZER-ALZ 2 |
| Clinical Endpoint |
35% slowing on iADRS, 36% on CDR-SB in low-to-medium tau patients |
| Plaque Clearance |
84% of patients achieved clearance at 76 weeks |
| Dosing |
Monthly IV infusion; treatment can be stopped upon plaque clearance |
| ARIA-E Rate |
24% (vs 2.1% placebo) |
| Key Feature |
Allows treatment discontinuation after plaque clearance |
| Property |
Details |
| Developer |
Biogen |
| Target |
Conformational epitopes on Aβ aggregates (plaques and oligomers) |
| Mechanism |
Human IgG1 antibody; promotes plaque clearance via microglia |
| FDA Status |
Accelerated approval (2021), withdrawn from market (2024) |
| Phase 3 Trials |
EMERGE (positive), ENGAGE (negative) |
| Clinical Endpoint |
High-dose EMERGE: 22% slowing on CDR-SB |
| Amyloid PET |
Significant plaque reduction in both trials |
| Dosing |
Monthly IV infusion (10 mg/kg) |
| ARIA-E Rate |
35.5% (high dose) |
| Post-market Data |
Real-world ARIA rates ~5%; mixed functional outcomes |
| Property |
Details |
| Developer |
Roche |
| Target |
Conformational epitopes on Aβ fibrils and plaques |
| Mechanism |
Fully human IgG1; binds to aggregated Aβ |
| FDA Status |
Not approved |
| Phase 3 Trials |
GRADUATE I & II |
| Clinical Endpoint |
Did not meet primary endpoint |
| Subgroup Analysis |
Potential benefit in lower tau pathology patients |
| Dosing |
Subcutaneous injection (weekly) |
| ARIA-E Rate |
25% |
| Property |
Details |
| Developer |
Genentech/Roche |
| Target |
Mid-domain tau (aa 6-23) |
| Mechanism |
Binds extracellular tau to block neuronal uptake and spreading |
| Clinical Stage |
Phase 2 (TAK-920/921) |
| Indication |
Alzheimer's disease, PSP |
| Trial Results |
Phase 2 in AD: reduced CSF tau, no cognitive benefit; Phase 2 in PSP: reduced tau PET, slower progression |
| Dosing |
Monthly IV infusion |
| Property |
Details |
| Developer |
AbbVie |
| Target |
N-terminal tau |
| Mechanism |
Targets extracellular tau to prevent propagation |
| Clinical Stage |
Phase 2 |
| Indication |
AD, PSP |
| Trial Results |
Did not meet primary endpoint in PSP |
| Dosing |
IV infusion |
| Property |
Details |
| Developer |
Biogen |
| Target |
N-terminal tau (fragment) |
| Mechanism |
Binds extracellular tau to block seeding |
| Clinical Stage |
Phase 2 (discontinued) |
| Indication |
AD, PSP |
| Trial Results |
Discontinued after Phase 2 did not meet primary endpoint |
| Dosing |
Monthly IV infusion |
| Property |
Details |
| Developer |
Johnson & Johnson |
| Target |
Phospho-tau (specific epitopes) |
| Mechanism |
Targets phosphorylated tau species |
| Clinical Stage |
Phase 1 |
| Indication |
Alzheimer's disease |
| Property |
Details |
| Developer |
Lundbeck |
| Target |
Phospho-tau (p-tau) |
| Mechanism |
Anti-phospho-tau antibody |
| Clinical Stage |
Phase 1 |
| Indication |
Alzheimer's disease |
| Feature |
Lecanemab |
Donanemab |
Aducanumab |
Anti-Tau Antibodies |
| Target |
Aβ protofibrils |
pE3-Aβ plaques |
Aβ aggregates |
Tau protein |
| FDA Approved |
Yes |
Yes |
Withdrawn |
No |
| Primary Indication |
Early AD |
Early AD |
Withdrawn |
AD, PSP, CBD |
| Trial Population |
MCI-mild AD |
Low-to-medium tau AD |
Early AD |
Early AD, PSP |
| Clinical Effect Size |
27% slower |
35% slower |
22% (high dose) |
Variable |
| Plaque Clearance |
55-70% |
84% |
60-70% |
N/A |
| Tau PET Reduction |
Moderate |
Moderate |
Moderate |
Variable |
| Biomarker Response |
p-tau217 ↓ |
p-tau217 ↓, NfL ↓ |
p-tau181 ↓ |
CSF p-tau ↓ |
| Treatment Duration |
Ongoing |
Can stop at clearance |
Ongoing |
Ongoing |
| Dosing Frequency |
Bi-weekly |
Monthly |
Monthly |
Monthly |
| Route |
IV infusion |
IV infusion |
IV infusion |
IV infusion |
flowchart TD
subgraph Pathological_Process
APP["APP"] --> BACE["BACE1"] --> Gamma["gamma-secretase"] --> Ab42["Abeta42"]
Ab42 --> OLIGO["Soluble Oligomers"]
OLIGO --> PROTO["Protofibrils"]
PROTO --> PLAQUE["Plaques"]
OLIGO --> TOXIC["Synaptotoxicity"]
TOXIC --> TAU["Tau Pathology"]
TAU --> NEURON["Neuronal Death"]
end
subgraph AntiAmyloid_Therapy
LECANEMAB["Lecanemab"] -.-> PROTO
DONANEMAB["Donanemab"] -.-> PLAQUE
ADUCANUMAB["Aducanumab"] -.-> PLAQUE
end
style AntiAmyloid_Therapy fill:#c8e6c9
style Pathological_Process fill:#ffcdd2
flowchart TD
subgraph Tau_Pathology
NORMAL_TAU["Normal Tau"] --> PHOS["Phosphorylation"]
PHOS --> AGGREGATE["Tau Aggregation"]
AGGREGATE --> NFT["Neurofibrillary Tangles"]
AGGREGATE --> SPREAD["Inter-neuronal Spread"]
SPREAD --> NEURONAL_LOSS["Neuronal Loss"]
end
subgraph AntiTau_Therapy
ANTITAU["Anti-Tau Antibodies"] -.->|"Bind extracellular tau"| SPREAD
ANTITAU -.->|"Clear NFTs"| NFT
ANTITAU -.->|"Block aggregation"| AGGREGATE
end
style AntiTau_Therapy fill:#e1f5fe
style Tau_Pathology fill:#ffcdd2
¶ ARIA Incidence by Antibody
| Antibody |
ARIA-E (edema) |
ARIA-H (hemorrhage) |
Key Risk Factors |
| Lecanemab |
12.6% |
17.3% |
APOE4 carriers, age >75 |
| Donanemab |
24.0% |
19.7% |
APOE4 carriers, higher dose |
| Aducanumab |
35.5% (high dose) |
19.1% |
APOE4, cerebral amyloid angiopathy |
| Anti-tau |
2-5% |
<5% |
Less frequent than anti-amyloid |
- Baseline MRI before treatment initiation
- APOE4 genotyping to identify high-risk patients
- Regular MRI monitoring (weeks 4, 12, 24, then annually)
- Dose titration for lecanemab
- Treatment discontinuation criteria for ARIA
| Factor |
Anti-Amyloid |
Anti-Tau |
| Disease Stage |
MCI to mild dementia |
Early disease preferred |
| Amyloid Status |
Must be amyloid-positive |
Amyloid may or may not be present |
| Tau Status |
Lower tau = better response |
Higher tau = may benefit more |
| Age |
<80 years optimal |
Similar considerations |
| APOE4 Status |
Monitor closely if carrier |
Generally safer profile |
| Biomarker |
Anti-Amyloid Use |
Anti-Tau Use |
| Amyloid PET |
Confirm baseline, monitor clearance |
Not primary target |
| Tau PET |
Secondary endpoint |
Primary endpoint |
| Plasma p-tau217 |
Treatment response |
Disease progression |
| Plasma p-tau181 |
Emerging |
Treatment response |
| CSF total tau |
Secondary |
Target engagement |
| CSF p-tau |
Secondary |
Target engagement |
- Anti-amyloid + anti-tau: Sequential or simultaneous targeting
- Anti-amyloid + neuroinflammation: Multi-target approaches
- Anti-tau + tau kinase inhibitors: Mechanistic combination
- Antibody + small molecule: Synergistic effects
- Blood-brain barrier penetration: Engineered antibodies with enhanced BBB transport
- Reduced ARIA risk: Modified Fc regions
- Dual-targeting: Bispecific antibodies
- Subcutaneous delivery: Improved convenience
| Domain |
Anti-Amyloid |
Anti-Tau |
| Mechanistic Clarity |
9 |
7 |
| Clinical Evidence |
8 |
5 |
| Preclinical Evidence |
9 |
8 |
| Replication |
8 |
4 |
| Effect Size |
6 |
4 |
| Safety/Tolerability |
5 |
8 |
| Biological Plausibility |
9 |
8 |
| Actionability |
8 |
4 |
Anti-amyloid antibodies (lecanemab, donanemab) have demonstrated disease-modifying effects in early Alzheimer's disease, representing a breakthrough in AD treatment. Anti-tau antibodies remain in development with mixed results—some showing biomarker effects but limited clinical benefit in AD, while showing more promise in pure tauopathies like PSP.
Key insights:
- Early intervention is critical for both approaches
- Patient selection (amyloid status, tau burden) significantly impacts outcomes
- ARIA remains a key safety consideration for anti-amyloid therapy
- Combination approaches may provide greater benefit than monotherapy
- Anti-tau therapy may complement anti-amyloid treatment for comprehensive disease modification