The Dominantly Inherited Alzheimer Network Trial (DIAN-TU-001) is a Phase 2/3 randomized, double-blind, placebo-controlled clinical trial evaluating disease-modifying therapies for individuals with autosomal dominant Alzheimer's disease (ADAD). This landmark trial represents the first preventive therapeutic trial in Alzheimer's disease, testing whether anti-amyloid antibodies can delay or prevent cognitive decline when administered years before symptom onset in genetically predisposed individuals.
The trial is conducted through the DIAN network, an international consortium established by the National Institute on Aging (NIA) to study individuals and families with autosomal dominant Alzheimer's disease. DIAN-TU-001 uses a innovative adaptive platform design, allowing evaluation of multiple therapeutic agents simultaneously against a common placebo control group.
The DIAN-TU trial represents a fundamental shift in AD clinical research:
Traditional Approach:
- Treatment after symptom onset
- Targets established disease
- Modest efficacy in late-stage trials
- Amyloid clearance without cognitive benefit (most trials)
DIAN-TU Approach:
- Treatment before symptoms
- Targets preclinical disease
- Preventive intervention paradigm
- First trial to test pre-symptomatic treatment
ADAD offers unique advantages for preventive trials:
Predictable Timeline:
- Age at onset within families (15-25 years before symptoms)
- Mutation carriers will develop disease (100% penetrance)
- Biomarker changes detectable decades before symptoms
- Enables enrichment for pre-symptomatic participants
Scientific Advantages:
- Uniform pathophysiology (single mutation)
- Earlier therapeutic window
- Clear treatment target (amyloid)
- Homogeneous population
| Field |
Value |
| Trial ID |
NCT01760005 |
| Phase |
Phase 2/3 |
| Status |
Active, Not Recruiting |
| Sponsor |
Washington University School of Medicine |
| Collaborators |
National Institute on Aging (NIA), Eli Lilly and Company, Roche/Genentech, Avid Radiopharmaceuticals |
| Start Date |
2012 |
| Estimated Completion |
2027 |
| Arm |
Intervention |
Dose |
Route |
| 1 |
Gantenerumab |
255-1200 mg Q2W |
Subcutaneous |
| 2 |
Solanezumab |
400-1400 mg Q4W |
Intravenous |
| 3 |
Placebo |
N/A |
Subcutaneous/IV |
- Target Enrollment: 490 participants
- Age Range: 18-80 years
- Condition: Autosomal Dominant Alzheimer's Disease (ADAD)
- Genetic Criteria: PSEN1, PSEN2, or APP mutations with known ADAD causation
¶ Expanded Genetic Background
The genetic basis of ADAD provides critical insights into disease pathogenesis and therapeutic target selection. Understanding the specific mutations helps contextualize the DIAN-TU trial population and informs interpretation of treatment outcomes.
PSEN1 located on chromosome 14 is the most common cause of ADAD, accounting for approximately 70-80% of all dominantly inherited cases. Over 300 pathogenic mutations have been identified in PSEN1, making it the single largest genetic contributor to early-onset AD.
Key characteristics of PSEN1 mutations:
- Early onset: Typically 30-50 years of age
- Penetrance: Near 100% for most mutations
- Phenotype: Classical AD presentation with memory impairment
- Progression: Variable rates, generally rapid
PSEN2 on chromosome 1 is a rarer cause of ADAD with unique features:
- Late onset: Typically 50-70 years of age
- Incomplete penetrance: Some carriers remain unaffected
- Phenotype: Variable, some behavioral features
- Geographic concentration: More common in certain populations
The Amyloid Precursor Protein gene on chromosome 21 contains mutations that increase Aβ production or alter the Aβ42/Aβ40 ratio:
- Duplications: APP gene duplication causes autosomal dominant AD
- Point mutations: Multiple pathogenic point mutations identified
- Swedish mutation: K670N/M671L (increased Aβ production)
- London mutation: V717I (increased Aβ42 production)
- Gantenerumab (Roche/Genentech) - Anti-amyloid monoclonal antibody
- Solanezumab (Eli Lilly) - Anti-amyloid monoclonal antibody
- ** placebo** (control arm)
- Intravenous infusion every 4 weeks
- Dose escalation period followed by maintenance dosing
- Cognitive Performance: Change in DIAN Multivariate Cognitive Composite (DIAN-MCC) score
- Clinical Dementia Rating Scale (CDR)
- Fluid Biomarkers: Change in cerebrospinal fluid (CSF) tau and amyloid markers
- Brain amyloid PET imaging (SUVr change)
- Brain volume changes (MRI)
- Cognitive subscale scores
- Functional assessment scales
¶ Randomization
- 1:1:1 randomization to gantenerumab, solanezumab, or placebo
- Stratified by mutation type, age, and baseline cognitive score
- Double-blind design maintained throughout treatment period
- Independent statistical analysis team
- Both gantenerumab and solanezumab showed dose-dependent reduction in brain amyloid
- Solanezumab: 14% reduction in amyloid plaques
- Gantenerumab: up to 59% reduction at highest dose
- No significant cognitive benefit at initial analysis
- Gantenerumab showed slowing of amyloid plaque accumulation
- Biomarker changes consistent with target engagement
- Ongoing analysis of cognitive outcomes through extended follow-up
- Age 18-80 years
- Confirmed PSEN1, PSEN2, or APP mutation carrier status
- Clinical diagnosis of mild cognitive impairment or dementia due to AD
- Mini-Mental State Examination (MMSE) score ≥ 20
- Able to provide informed consent
- Any neurological condition other than AD
- Psychiatric disorder requiring current treatment
- History of stroke or transient ischemic attack
- Current anticoagulant therapy
- MRI evidence of significant cerebrovascular disease
¶ Sites and Locations
The trial is conducted at multiple DIAN sites worldwide:
- Washington University School of Medicine (St. Louis, USA) - Lead site
- University of California (San Francisco, USA)
- Columbia University (New York, USA)
- University of Pittsburgh (USA)
- University of Toronto (Canada)
- University College London (UK)
- Karolinska Institute (Sweden)
- Tokyo Metropolitan Institute of Gerontology (Japan)
Autosomal Dominant Alzheimer's Disease (ADAD) accounts for approximately 1% of all Alzheimer's cases but provides critical insights into disease pathogenesis. Three genes are implicated:
- PSEN1 (Presenilin 1): Most common cause, with over 300 mutations identified
- PSEN2 (Presenilin 2): Rarer, with typically later onset
- APP (Amyloid Precursor Protein): Duplications and point mutations
The DIAN-TU trial specifically targets individuals carrying pathogenic mutations in these genes, enabling study of disease mechanisms decades before symptom onset.
The amyloid cascade hypothesis posits that Aβ accumulation initiates a pathogenic cascade leading to tau pathology, synaptic loss, and cognitive decline. In ADAD:
- Mutation carriers develop Aβ plaques 15-25 years before cognitive symptoms
- This predictable timeline enables preventive interventions
- DIAN-TU tests whether anti-amyloid therapies can delay or prevent cognitive decline when administered pre-symptomatically
Gantenerumab is a fully human IgG1 monoclonal antibody that binds to aggregated forms of Aβ, including plaques:
- Mechanism: Fc-mediated microglial engagement and plaque removal
- Dosing: Subcutaneous administration every 2 weeks
- Target engagement: Dose-dependent reduction in amyloid PET signal
- Development history: Originally failed in GRADUATE Phase 3; reformulated at higher doses for DIAN
Solanezumab binds to the central domain of Aβ monomers:
- Mechanism: Soluble Aβ neutralization, not plaque removal
- Dosing: Intravenous infusion monthly
- Target engagement: Increases CSF Aβ40/42 (suggesting redistribution from plaques)
- Development history: Failed in EXPEDITION Phase 3 for sporadic AD; selected for DIAN based on different mechanism
DIAN-TU employs the ATN (Amyloid, Tau, Neurodegeneration) biomarker framework:
| Biomarker Category |
Assessments Used |
| A (Amyloid) |
CSF Aβ42/40 ratio, Amyloid PET (Pittsburgh compound B) |
| T (Tau) |
CSF p-tau181, t-tau; Tau PET |
| N (Neurodegeneration) |
MRI volumetrics, FDG-PET, CSF NfL |
Gantenerumab is a fully human IgG1 monoclonal antibody with unique properties:
Binding Characteristics:
- Binds to amino acids 3-16 of Aβ N-terminus
- Prefers aggregated forms (oligomers, plaques)
- Does not bind monomeric Aβ
- High affinity for dense-core plaques
Mechanism of Plaque Removal:
- Fc-mediated microglial engagement
- Antibody-dependent cellular cytotoxicity (ADCC)
- Complement activation
- Fcγ receptor-mediated phagocytosis
Clinical Effects:
- Dose-dependent plaque reduction (up to 59%)
- Reduced CSF Aβ42 (redistribution from plaques)
- Increased plasma Aβ (peripheral sink)
- ARIA risk at higher doses
Solanezumab has a different mechanism:
Binding Characteristics:
- Binds to mid-domain of Aβ (residues 13-28)
- Prefers monomeric forms
- Does not bind plaques
- Lower affinity than gantenerumab
Mechanism of Action:
- Neutralizes soluble Aβ species
- Prevents aggregation into oligomers
- May promote clearance pathways
- No direct plaque binding
Clinical Effects:
- Modest CSF Aβ increase
- No significant plaque reduction
- No ARIA risk (different mechanism)
- Lower potency than gantenerumab
| Property |
Gantenerumab |
Solanezumab |
| Target |
Plaques + oligomers |
Monomers |
| Mechanism |
Plaque removal |
Neutralization |
| Plaque reduction |
Yes (dose-dependent) |
No |
| ARIA risk |
Yes |
No |
| Amyloid PET |
Decreases |
No change |
| CSF Aβ42 |
Increases |
Increases |
DIAN-TU uses the ATN biomarker framework:
A (Amyloid):
- CSF Aβ42/40 ratio (lower = positive)
- Amyloid PET (SUVr ≥1.2)
- Required for trial enrollment
T (Tau):
- CSF p-tau181 (elevated = positive)
- CSF t-tau (elevated = neurodegeneration)
- Tau PET (optional)
N (Neurodegeneration):
- MRI brain volume (reduced = positive)
- FDG-PET hypometabolism
- CSF NfL (elevated = neurodegeneration)
The biomarker changes follow a predictable pattern:
- Amyloid changes (first): 20-25 years before symptoms
- Tau changes (second): 15-20 years before symptoms
- Neurodegeneration (third): 10-15 years before symptoms
- Cognitive changes (fourth): symptom onset
This sequence enables preventive intervention at stages 1-3.
The most common cause of ADAD:
Mutation Characteristics:
- Over 300 pathogenic mutations
- Encoding presenilin-1 (γ-secretase)
- Generally earlier onset
- Highly penetrant
Common Mutations:
- A246E, H163R, P264L
- Various phenotypic effects
- Variable age at onset
Rarer than PSEN1:
Mutation Characteristics:
- ~40 pathogenic mutations
- Encoding presenilin-2
- Later onset than PSEN1
- Reduced penetrance in some
Rare cause of ADAD:
Mutation Characteristics:
- Duplications
- Point mutations at cleavage sites
- Swedish mutation (KM670/671NL)
- London mutation (V717I)
DIAN-TU sites must meet rigorous standards:
Clinical Infrastructure:
- Memory disorders clinic
- Neurology department
- Research nursing
- Clinical trial infrastructure
Biomarker Capabilities:
- MRI facilities
- PET imaging (amyloid, tau)
- CSF collection and processing
Laboratory Capabilities:
- Genetic testing
- Biomarker assays
- Sample storage
Trial participation requires significant commitment:
Visit Schedule:
- Monthly visits for first year
- Every 3 months thereafter
- 52 weeks primary endpoint
- Extended follow-up
Procedures:
- Cognitive testing (2-3 hours)
- MRI scans
- PET scans (baseline, 52 weeks)
- CSF collection
- Blood draws
DIAN-TU informs future preventive trials:
Expanding Pipeline:
- New anti-amyloid antibodies
- Anti-tau therapies
- Combination approaches
- Neuroprotective agents
Broader Populations:
- Sporadic AD prevention
- Down syndrome population
- Earlier intervention
- Broader biomarker enrollment
The DIAN-TU trial provides key lessons:
- Preventive trials are feasible in genetically defined populations
- Extended timelines needed for preventive endpoints
- Biomarker enrichment enables pre-symptomatic treatment
- Platform designs reduce costs and accelerate development
The primary cognitive endpoint uses a composite sensitive to early changes:
- Rey Auditory Verbal Learning Test (RAVLT): Verbal memory
- Digit Symbol Substitution Test (DSST): Processing speed
- Category Fluency: Semantic memory
- Trail Making Test Part A: Attention and psychomotor speed
The CDR remains the gold standard for staging:
- CDR 0: Cognitively normal
- CDR 0.5: Mild cognitive impairment
- CDR 1: Mild dementia
- CDR 2: Moderate dementia
- CDR 3: Severe dementia
With 490 participants and anticipated ~30% mutation carrier rate in placebo arm:
- Power calculations: 80% power to detect 50% slowing of cognitive decline
- Multiple comparison adjustments: Primary analysis uses Hochberg procedure
- Missing data handling: Multiple imputation under MAR assumption
The statistical analysis plan defines rigorous methods:
- Intent-to-treat (ITT) population: All randomized participants
- Modified ITT (mITT): Participants receiving at least one dose
- Per-protocol: Participants completing planned treatment
- Safety population: All participants with safety data
Given multiple treatment arms and endpoints:
- Primary analysis: Hochberg procedure for multiple comparisons
- Control of family-wise error rate: ≤0.05 (two-sided)
- Secondary confirmatory: Graphical approach for gatekeeping
Pre-specified sensitivity analyses include:
- Per-protocol analysis: Excluding major protocol deviations
- Completer analysis: Participants completing full treatment
- Imputation methods: Multiple approaches for missing data
- Subgroup analyses: Pre-specified effect modification
| Biomarker |
Fluid |
Imaging |
Readout |
| CSF Aβ42 |
✓ |
- |
Concentration |
| CSF Aβ40 |
✓ |
- |
Concentration |
| PET PiB |
- |
✓ |
SUVr |
| PET Florbetapir |
- |
✓ |
SUVr |
| Biomarker |
Fluid |
Imaging |
Readout |
| CSF t-tau |
✓ |
- |
Concentration |
| CSF p-tau181 |
✓ |
- |
Concentration |
| CSF p-tau217 |
✓ |
- |
Concentration |
| Tau PET |
- |
✓ |
SUVr |
| Biomarker |
Fluid |
Imaging |
Readout |
| MRI volumetrics |
- |
✓ |
Volume change |
| FDG-PET |
- |
✓ |
Metabolism |
| CSF NfL |
✓ |
- |
Concentration |
| CSF NfH |
✓ |
- |
Concentration |
The trial employs biomarker enrichment:
- CSF biomarker positivity: Required for full analysis population
- Genetic confirmation: Documented mutation carrier status
- Age at symptom onset estimation: Based on family history
The amyloid cascade hypothesis is directly testable in ADAD:
Aβ Production:
- Pathogenic mutations increase Aβ production
- PSEN mutations enhance Aβ42/Aβ40 ratio
- APP duplications increase total Aβ
- 100% of mutation carriers develop Aβ deposits
Aβ Deposition Timeline:
- 20-25 years before symptoms: Aβ PET positive
- 15-20 years before symptoms: CSF Aβ42 reduced
- 10-15 years before symptoms: tau changes begin
- Symptom onset: neurodegeneration established
Therapeutic Implications:
- Early intervention possible before symptoms
- Amyloid clearance may prevent downstream effects
- Optimal treatment before tau spread
- Window for disease modification
The trial uses amyloid PET as a key biomarker:
Imaging Agent:
- 11C-PiB (Pittsburgh compound B)
- 18F-florbetapir (Amyvid)
- 18F-florbetaben (Neuraceq)
Interpretation:
- SUVr ≥1.2 = amyloid positive
- Cortical binding pattern
- Gray matter specificity
Clinical Correlation:
- Strong correlation with CSF Aβ42
- Predicts cognitive decline
- Therapeutic target engagement
DIAN-TU pioneered adaptive platform trials in AD:
Platform Advantages:
- Multiple drugs, single placebo arm
- Shared infrastructure
- Efficient patient enrollment
- Accelerated development
Drug Selection Criteria:
- Biological rationale
- Safety profile
- Manufacturing feasibility
- Regulatory alignment
Adaptations:
- Dose adjustments
- Population enrichment
- Endpoint modifications (pre-specified)
Sample Size Calculations:
- Based on expected effect size
- Assumes 50% slowing
- Accounts for dropout
- Power: 80%
Multiple Comparisons:
- Hochberg procedure
- Control family-wise error rate
- Pre-specified hierarchies
- Secondary endpoints exploratory
Missing Data:
- Multiple imputation
- Last observation carry forward
- Sensitivity analyses
Recruitment in rare populations requires:
Family-Based Approaches:
- Extended family screening
- At-risk relative identification
- Genetic counseling services
- Multi-generational enrollment
International Coordination:
- Global site distribution
- Local recruitment
- Cultural adaptation
- Regulatory harmonization
Retention Strategies:
- Long-term engagement
- Transportation support
- Compensation
- Caregiver support
Preventive trials require extended observation:
Timeframe Considerations:
- Decades needed for primary endpoints
- Ethical considerations
- Drug supply challenges
- Participant burden
Approaches:
- Open-label extensions
- Registry follow-up
- Natural history studies
- Deferred treatment
The DIAN-TU model is informing sporadic AD prevention:
A4 Study (Anti-Amyloid in Asymptomatic AD):
- Cognitively normal
- Amyloid PET positive
- Solanezumab treatment
- Primary prevention trial
DIAN-TU for Scientists:
- Similar design
- Broader population
- Multiple biomarkers
- Prevention focus
DIAN-TU expanded beyond amyloid:
Tau-Targeting:
- Anti-tau antibodies
- Tau aggregation inhibitors
- Tau PET ligands
Synaptic Protection:
- Synaptic functional recovery
- Synaptic density PET
- Neuroprotective agents
Neuroinflammation:
- Microglial modulators
- Anti-inflammatory approaches
- TREM2 targeting
DIAN-TU has influenced the broader AD research field:
- Pre-symptomatic treatment paradigm: Established feasibility of preventive trials
- Genetic stratification: Demonstrated utility of enrichment biomarkers
- Biomarker-driven trials: ATN framework adoption in sporadic AD trials
- Platform trial infrastructure: Informed design of similar programs
- Family-based recruitment through DIAN network
- Centralized biomarker core facilities
- Standardized cognitive assessment training
- International site coordination
- Slow enrollment due to rarity of ADAD
- Drug supply interruptions
- COVID-19 pandemic impacts
- Regulatory complexities of multi-national platform
Comparing features of DIAN-TU to typical sporadic AD trials:
| Feature |
DIAN-TU |
Sporadic AD Trials |
| Enrollment |
Family-based |
Individual |
| Age range |
Variable |
Generally older |
| Biomarkers |
Required |
Optional |
| Timing |
Pre-symptomatic |
Symptomatic |
| Outcome |
Delay onset |
Slow progression |
Key insights from this comparison:
- Genetics enable enrichment: Single biomarker (mutation status)
- Predictable timeline: Known age at onset from family data
- Target population: Specific for prevention
- Regulatory path: May differ from symptomatic trials
Different PSEN1 mutations show phenotypic variation:
| Mutation |
Age of Onset |
Cognitive Profile |
Progression |
| A431E |
33-35 |
Rapid |
Fast |
| L286P |
38-42 |
Typical |
Variable |
| H163R |
45-50 |
Behavioral |
Moderate |
| M146L |
48-55 |
Typical |
Slow |
Global distribution of ADAD mutations:
- North America: PSEN1 dominant
- Europe: Mixed distribution
- Asia: PSEN1 and APP more common
- Colombia: PSEN1 E280A founder effect
¶ Anti-Amyloid Antibody Development
Gantenerumab (RO4904986) has undergone extensive development:
- Early development: First tested in mild-moderate AD
- Grade Phase 3: Failed to meet endpoints in sporadic AD
- Re-formulation: Higher doses for DIAN-TU
- GRADUATE: New Phase 3 in sporadic AD
- DIAN-TU: Primary trial in ADAD
Solanezumab (LY2062430) has complementary history:
- Original indication: Mild-moderate AD
- EXPEDITION trials: Failed in Phase 3
- Mechanistic insight: Soluble Aβ targeting
- DIAN-TU: Different mechanism, ADAD focus
- Cognition effects: Subgroup signals observed
The DIAN-TU program has engaged with FDA:
- INDClearance: Multiple INDs for each agent
- Special protocol assessments: Protocol guidance
- Accelerated approval: Based on biomarker endpoints
- Real-time oncology: Not applicable
International regulatory considerations:
- FDA: US registration
- EMA: European submission
- PMDA: Japanese collaboration
- Health Canada: Canadian sites
The DIAN-TU network includes:
| Region |
Sites |
Countries |
| North America |
15 |
US, Canada |
| Europe |
12 |
UK, Germany, Sweden |
| Asia-Pacific |
5 |
Japan, Australia |
Core facilities support the trial:
- Biomarker core: CSF and imaging
- Genetic core: Mutation confirmation
- Statistical core: Analysis coordination
- Pharmacovigilance: Safety monitoring
Participants completing DIAN-TU may:
- Join DIAN-O: Continued observation
- Open-label extension: Active treatment access
- Natural history: Continue in registry
- Family studies: Extended participation
DIAN data enables research:
- Qualified researchers: Access applications
- Publication policies: Authorship guidelines
- External science platform: Data access
DIAN provides genetic counseling:
- Pre-symptomatic testing: Optional, with support
- Family planning: Reproductive options
- Psychological support: Available for participants
- Long-term follow-up: Continued care
Participants join for various reasons:
- Family benefit: Contribute to research
- Advance knowledge: Scientific contribution
- Potential treatment: Access to therapies
- Legacy: Help future generations
DIAN-TU informs future trials:
- DIAN-TU-002: Next platform trial
- Combination approaches: Multiple mechanisms
- Earlier intervention: Prevention in children
- Genetic therapies: CRISPR approaches
Future biomarker needs:
- Response prediction: Which patients benefit
- Dosing optimization: PK/PD relationships
- Disease staging: Individualized treatment timing
- Safety monitoring: Early detection
The amyloid cascade hypothesis in ADAD context proposes:
flowchart LR
A["APP Processing"] --> B["Amyloid Beta"]
B --> C["Aβ Monomers"]
C --> D["Aβ Oligomers"]
D --> E["Aβ Plaques"]
E --> F["Tau Pathology"]
F --> G["Synaptic Loss"]
G --> H["Cognitive Decline"]
Key implications for therapy:
- Early intervention: Before plaque formation
- Multi-target approaches: Beyond Aβ reduction
- Genetic targeting: Mutation-specific effects
- Combination strategies: Synergistic approaches
The cognitive assessments used in DIAN-TU include:
Primary Cognitive Composite (DIAN-MCC)
| Component |
Test |
Domain |
| Memory |
RAVLT |
Verbal learning |
| Attention |
DSST |
Processing speed |
| Language |
Category fluency |
Semantic memory |
| Executive |
Trail Making A |
Psychomotor speed |
Secondary Measures
| Measure |
Domain |
Administration |
| MMSE |
Global cognition |
Annual |
| CDR |
Clinical staging |
Annual |
| FCSRT |
Episodic memory |
Annual |
| Trail Making B |
Executive function |
Annual |
DIAN-TU employs comprehensive imaging:
MRI Protocol
- T1-weighted: Volumetric analysis
- T2/FLAIR: White matter lesions
- Diffusion tensor: White matter integrity
- Resting state fMRI: Functional connectivity
PET Protocol
- Amyloid PET: Florbetapir/florbetaben
- Tau PET: MK-6240 or FTP
- FDG-PET: Glucose metabolism
DIAN-TU collects multiple biospecimens:
| Specimen |
Collection |
Processing |
| CSF |
Lumbar puncture |
Aliquoted, frozen |
| Blood |
Venipuncture |
Plasma, serum, DNA |
| Urine |
Spot collection |
Aliquoted, frozen |
Sites must meet quality standards:
- GCP compliance: International standards
- Laboratory certification: CAP/CLIA
- Imaging certification: Blinded reads
- Regulatory compliance: FDA/EMA
Maintaining participant engagement:
- Regular contact: Phone and email updates
- Flexible scheduling: Accommodating travel
- Compensation: Reasonable financial support
- Appreciation: Thank you communications
Data sharing and publication:
- Primary results: First publication reserved
- Secondary analyses: Approved access
- Collaboration: Encouraged research
- Open science: Data sharing initiatives
The DIAN-TU adaptive platform design offers several advantages:
- Efficiency: Shared placebo group
- Flexibility: Add new agents
- Statistical power: Larger control group
- Participant access: Multiple treatment options
- Rapid evaluation: Earlier go/no-go decisions
¶ Limitations and Mitigation
Acknowledged limitations with mitigation strategies:
| Limitation |
Mitigation |
| Small population |
International network |
| Variable onset age |
Biomarker enrichment |
| Long timecourse |
Surrogate endpoints |
| Multiple mutations |
Genetic stratification |
¶ Funding and Support
DIAN-TU is funded through:
- National Institute on Aging: Primary funder
- Foundation grants: Alzheimer's Association
- Industry partnerships: Roche, Lilly
- International contributions: Multiple sources
¶ Education and Training
¶ Standardized Training
Sites receive comprehensive training:
- Cognitive assessment: Certification required
- Imaging acquisition: Scanner-specific protocols
- Biospecimen collection: GCP compliance
- Safety reporting: Adverse event classification
Comprehensive safety oversight:
- Data Safety Monitoring Board: Independent review
- Site monitoring: Source data verification
- Adverse event reporting: Real-time tracking
- Medical monitoring: 24-hour coverage
- First Prevention Trial: Tests whether treating before symptoms can delay or prevent cognitive decline
- Genetic Enrichment: Uses known mutation carriers for predictable disease course
- Biomarker Framework: Establishes ATN classification for AD diagnosis and staging
- Platform Design: Pioneers efficient testing of multiple therapies
- Field Impact: Informs sporadic AD prevention trials
The implications extend beyond this trial:
For Patients:
- Family members can be screened and potentially enrolled
- Early identification enables planning
- Research participation provides access to new therapies
- Hope for future prevention
For Families:
- Genetic counseling services
- Family screening programs
- Intergenerational research opportunities
- Support for rare disease communities
For Researchers:
- Trial design model
- Biomarker validation data
- Natural history information
- Collaborative infrastructure
For the Field:
- Prevention paradigm validation
- Platform trial design
- Regulatory precedent
- Funding models
- Enrollment: Complete (490 participants)
- Primary Endpoint: Expected 2027
- Drug Effects: Gantenerumab shows amyloid reduction; cognitive data pending
- Future: Next-generation trials expanding to sporadic AD
If preventive treatment succeeds:
- Treatment could begin decades before symptoms
- Biomarker screening enables early identification
- Combination approaches may provide additional benefit
- Could transform AD from inevitable to preventable
Trial participants and families have shared important perspectives:
Motivation for Participation:
- Family history motivates action
- Desire to help future generations
- Access to expert care
- Contributing to science
Challenges:
- Frequent visits over extended period
- Invasive procedures (lumbar punctures)
- Uncertainty about drug assignment
- Long-term commitment
Rewards:
- Contributing to breakthrough
- Advanced monitoring
- Access to treatments
- Community connection
DIAN-TU established important infrastructure:
Data Sharing:
- Centralized database
- Standardized protocols
- Open science policies
- Collaborative analyses
Biological Samples:
- CSF repository
- DNA repository
- Brain bank linkage
- Long-term storage
Imaging Repository:
- MRI archives
- PET archives
- Standardized processing
- Multi-center validation
The trial has generated numerous publications:
Trial Design:
- Rationale and design papers
- Statistical analysis plans
- Regulatory interactions
- Methodological papers
Biomarker Studies:
- ATN validation
- Baseline characteristics
- Correlation studies
- Method development
Clinical Outcomes:
- Primary results
- Secondary analyses
- Subgroup studies
- Long-term follow-up
AD represents a major global health challenge:
Epidemiology:
- 55 million people with dementia worldwide
- AD is 60-70% of cases
- 10 million new cases annually
- Projected doubling by 2050
Economic Impact:
- Annual cost: $1.3 trillion (2023)
- Direct and indirect costs
- Caregiver burden
- Healthcare system strain
Research Investment:
- Growing but insufficient
- Need for preventive approaches
- Platform trials efficiency
- International collaboration