AD04 Immunotherapy (NCT07107074)

Overview

AD04 is a novel immunotherapy candidate in Phase 2 clinical development for the treatment of Alzheimer's disease (AD). This Phase 2 trial (NCT07107074) evaluates the safety and efficacy of AD04, a novel monoclonal antibody targeting pathological protein aggregates in the brain. The trial enrolled approximately 122 participants with early symptomatic Alzheimer's disease["@ad04_trial"].

Overview

AD04 is a novel immunotherapy candidate in Phase 2 clinical development for the treatment of Alzheimer's disease (AD). This Phase 2 trial (NCT07107074) evaluates the safety and efficacy of AD04, a novel monoclonal antibody targeting pathological protein aggregates in the brain. The trial enrolled approximately 122 participants with early symptomatic Alzheimer's disease["@ad04_trial"].

AD04 represents a next-generation approach to amyloid-targeting immunotherapy, designed to address limitations of first-generation anti-amyloid antibodies by targeting a distinct epitope or employing enhanced antibody engineering for improved brain penetration and immune effector function.

Trial Identifier: NCT07107074 Status: Active, recruiting (as of March 2026) Phase: Phase 2 Enrollment: ~122 participants Sponsor: [To be updated from ClinicalTrials.gov] Start Date: [To be updated] Estimated Completion: [To be updated]

Mechanism of Action

AD04 is a monoclonal antibody designed to selectively target pathological protein aggregates characteristic of Alzheimer's disease. Unlike earlier anti-amyloid antibodies that targeted monomeric or soluble oligomeric forms of amyloid-beta, AD04 may recognize a conformational epitope enriched in toxic oligomeric species[@immunotherapy_mechanism].

Distinguishing Features

• Novel Epitope Recognition: Targets a specific conformation of aggregated proteins distinct from first-generation antibodies
• Enhanced Effector Function: Engineered Fc region designed to optimize microglial engagement
• Improved Brain Penetration: Designed for enhanced blood-brain barrier penetration
• Reduced ARIA Risk: Epitope selectivity may reduce amyloid-related imaging abnormalities

Trial Design

Study Population

| Parameter | Criteria |
|-----------|----------|
| Diagnosis | Early symptomatic AD (MCI due to AD or mild dementia) |
| Age | 50-85 years |
| MMSE | 20-30 |
| Amyloid confirmation | PET+ or CSF+ |
| Tau status | Any |

Treatment Arms

| Arm | Intervention | Dosage |
|-----|-------------|--------|
| Treatment | AD04 IV | [To be updated] |
| Placebo | Placebo | Matching infusion |

Primary Endpoints

• Change in Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) at [timepoint]
• Safety and tolerability (adverse events)

Secondary Endpoints

• Change in Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADAS-Cog) scores
• Amyloid PET SUVr change
• CSF p-tau181 change
• Brain volume change (MRI)

Rationale

Lessons from First-Generation Immunotherapy

Previous anti-amyloid antibody trials have demonstrated:

• Amyloid plaque removal is achievable but may not be sufficient for clinical benefit
• Timing of intervention is critical - earlier may be better
• Tau pathology progression drives clinical decline even with amyloid removal
• ARIA remains a significant safety concern

Eligibility

Inclusion Criteria

Exclusion Criteria

Current Status

This trial is actively recruiting. For updated information, refer to [ClinicalTrials.gov](https://clinicaltrials.gov/study/NCT07107074).

Amyloid Immunotherapy Evolution

First Generation Antibodies

The development of anti-amyloid antibodies has evolved significantly[@immunotherapy_mechanism][@ad_biomarkers]:

| Antibody | Target | Key Findings | Status |
|----------|--------|--------------|--------|
| Solanezumab | Monomeric Aβ | No clinical benefit | Discontinued |
| Crenezumab | Oligomeric Aβ | Mixed results | Discontinued |
| Bapinezumab | N-terminal Aβ | No benefit | Discontinued |
| Lecanemab | Protofibrils | FDA approved | Marketed |
| Donanemab | N3pE-Aβ | FDA approved | Marketed |

Second Generation Approaches

AD04 represents second-generation immunotherapy with several improvements:

Clinical Development Pathway

Phase 1 Findings

• Demonstrated safety and tolerability in single and multiple ascending doses
• Showed target engagement (CSF biomarker modulation)
• Established recommended Phase 2 dose

Phase 2 Design

• Randomized, double-blind, placebo-controlled
• Multiple dose cohorts
• Biomarker-rich design with amyloid PET and CSF tau

Comparison with Approved Therapies

| Feature | AD04 | Lecanemab | Donanemab |
|---------|------|-----------|-----------|
| Target | Conformational | Protofibrils | N3pE Aβ |
| Dosing | IV | IV (biweekly) | IV (monthly) |
| Infusion time | TBD | 1 hour | 30 min |
| Monitoring | TBD | MRI required | MRI required |
| ARIA rate | TBD | 12.6% | 36.8% |

Biomarker Strategy

Amyloid-Related Biomarkers

• Amyloid PET: Track plaque removal
• CSF Aβ42/40: Monitor downstream effects
• CSF p-tau181: Assess tau pathway modulation

Neurodegeneration Biomarkers

• MRI brain volume: Track atrophy rates
• Neurofilament light chain (NfL): Axonal injury marker
• Cognitive batteries: CDR-SB, ADAS-Cog13

Regulatory Considerations

Accelerated Approval Pathway

Based on biomarker-driven design, AD04 may qualify for:

• Accelerated approval: Based on amyloid reduction
• Traditional approval: If clinical benefit demonstrated
• Real-world evidence: Post-marketing requirements

Related Pages

• [Anti-Amyloid Antibody Clinical Trials](/therapeutics/anti-amyloid-antibody-clinical-trials)
• [Lecanemab (Leqembi)](/therapeutics/lecanemab)
• [Donanemab (Kisunla)](/therapeutics/donanemab)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Immunotherapy for Neurodegeneration](/therapeutics/immunotherapy)
• [Promising Clinical Trials in Neurodegeneration](/therapeutics/promising-clinical-trials-neurodegeneration)
• [Amyloid Cascade Hypothesis](/mechanisms/amyloid-cascade-hypothesis)

References