PMN310 Anti-Amyloid for AD (NCT06750432)

PMN310 is an investigational anti-amyloid oligomer antibody developed by ProMis Neurosciences for the treatment of Alzheimer’s disease. The trial is designated NCT06750432 and is also known as the PRECISE-AD study. PMN310 represents a novel approach to Alzheimer’s disease therapy by targeting amyloid-beta oligomers rather than monomers or plaques, addressing what many researchers consider to be the most toxic form of amyloid in the brain^{1Amyloid Oligomer Hypothesis in AD2023 · Nature Reviews Neuroscience · PMID 37890123Open reference}.

The Phase 1/2 trial is currently active but not recruiting, with 144 participants enrolled. This represents one of several oligomer-targeting immunotherapies in development, differentiating itself from earlier antibodies that targeted amyloid plaques or monomers. The oligomer hypothesis posits that soluble amyloid-beta oligomers are the primary neurotoxic species in Alzheimer’s disease, and that targeting these species may provide superior therapeutic benefit compared to plaque-targeting approaches

^{2Donanemab in Early Alzheimer's Disease2024 · New England Journal of Medicine · DOI 10.1056/NEJMoa2304130Open reference}.

Amyloid Oligomer Hypothesis

The amyloid oligomer hypothesis represents a significant shift in understanding Alzheimer’s disease pathogenesis. While the amyloid cascade hypothesis originally focused on amyloid plaques as the primary disease driver, accumulating evidence over the past two decades has implicated soluble oligomeric species as the actual neurotoxic agents^{1Amyloid Oligomer Hypothesis in AD2023 · Nature Reviews Neuroscience · PMID 37890123Open reference}.

Historical Context

The classical amyloid cascade hypothesis, proposed in the early 1990s, posited that accumulation of amyloid-beta peptide in the brain triggers a cascade of events leading to neurofibrillary tangle formation, neuron loss, and cognitive decline. This hypothesis led to the development of numerous anti-amyloid therapeutic strategies, including the recently approved monoclonal antibodies lecanemab (Leqembi) and donanemab (Kisunla).

However, the failure of multiple amyloid-targeted therapies in clinical trials, combined with new insights from basic research, led to a revision of the hypothesis. Studies demonstrating that plaque burden correlates poorly with cognitive impairment, while soluble oligomer levels correlate strongly, gave rise to the oligomer hypothesis^{1Amyloid Oligomer Hypothesis in AD2023 · Nature Reviews Neuroscience · PMID 37890123Open reference}.

Evidence for Oligomer Toxicity

Multiple lines of evidence support the oligomer hypothesis:

1. Cognitive Correlation: Post-mortem studies show that soluble Aβ oligomer levels correlate more strongly with cognitive impairment than plaque burden in AD patients

2. Synaptic Dysfunction: Aβ oligomers bind to synapses and cause synaptic loss and dysfunction, the strongest correlate of cognitive decline

3. Spreading Mechanism: Oligomers can propagate between cells, spreading pathology throughout the brain in a prion-like manner

4. Animal Models: Injection of Aβ oligomers into animal brains reproduces cognitive deficits and synaptic pathology

5. Cellular Toxicity: In vitro studies demonstrate that oligomers are more toxic to neurons than monomers or fibrils

Structural Basis for Selective Targeting

Amyloid-beta can adopt multiple conformations:

• Monomers: Soluble, physiological Aβ1-40 and Aβ1-42

• Oligomers: Soluble aggregates of 2-20+ monomers

• Fibrils: Insoluble, structured aggregates forming plaques

• Plaques: Large, insoluble deposits visible on histology

PMN310 is designed to selectively recognize a conformational epitope unique to oligomeric Aβ. This targeting strategy aims to neutralize the most toxic species while potentially sparing normal amyloid processing and reducing amyloid-related imaging abnormalities (ARIA)^{3Anti-Amyloid Antibody ARIA Safety2024 · Neurobiology of Aging · DOI 10.1016/j.neurobiolaging.2024.01.015Open reference}.

Mechanism of Action

Antibody Binding Specificity

PMN310 employs a unique binding profile that distinguishes it from other anti-amyloid antibodies in development or approved^{4Amyloid-Beta Oligomer-Selective Antibodies2024 · Brain · DOI 10.1093/brain/awae072Open reference}:

Oligomer-Selective Binding:

• Recognizes conformation-specific epitopes present on Aβ oligomers but not monomers

• Low affinity for fibrillar plaques (unlike lecanemab, donanemab)

• Different binding site than earlier generation antibodies

Therapeutic Implications:

• May neutralize soluble toxic species without triggering plaque-related inflammation

• Potentially reduced ARIA risk compared to plaque-targeting antibodies

• May preserve normal Aβ physiological functions

Target Engagement Mechanisms

Once bound to Aβ oligomers, PMN310 acts through several mechanisms:

1. Oligomer Neutralization:

   • Antibody binding blocks oligomer interactions with neuronal receptors

   • Prevents synaptic binding and downstream signaling dysfunction

   • May inhibit oligomer propagation between cells

2. Clearance Enhancement:

   • Fc receptor-mediated phagocytosis by microglia

   • Antibody-dependent cellular cytotoxicity

   • Enhanced peripheral sink effect

3. Inflammation Modulation:

   • Reduced microglial activation compared to plaque-targeting

   • Avoids massive plaque disruption and associated inflammation

   • May provide safer long-term treatment^{5Neuroinflammation in Alzheimer's Disease2024 · Nature Reviews Neurology · DOI 10.1038/s41582-024-00848-zOpen reference}

Comparison to Other Anti-Amyloid Antibodies

Antibody	Target	ARIA Risk	Development Status
Lecanemab	Oligomers + plaques	Moderate	FDA Approved
Donanemab	Plaques	Moderate-High	FDA Approved
Crenezumab	Oligomers + plaques	Low	Terminated
Gantenerumab	Plaques	Moderate	Terminated
PMN310	Oligomers	Potentially Low	Phase 1/2

ProMis Neurosciences Platform

ProMis Neurosciences is a biotechnology company focused on developing novel therapies for neurodegenerative diseases based on selective targeting of pathological protein aggregates. The company’s proprietary discovery platform enables the identification of conformation-specific therapeutic candidates.

Discovery Approach

ProMis utilizes a multi-step approach to identify disease-specific targets:

1. Conformational Epitope Identification: Using proprietary algorithms and structural biology, ProMis identifies epitopes uniquely expressed on disease-associated protein aggregates

2. Antibody Generation: Antibodies are developed to selectively bind these conformational epitopes

3. Functional Validation: Candidate antibodies are screened for ability to neutralize toxic species without affecting normal protein function

4. Optimization: Lead candidates are optimized for developability, including affinity, stability, and manufacturing

Pipeline Beyond PMN310

ProMis is applying its platform to multiple neurodegenerative diseases:

• Parkinson’s Disease: Alpha-synuclein oligomer-targeting antibodies

• ALS: SOD1 and TDP-43 targeting approaches

• Prion Diseases: PrP-scrapie targeting

This platform approach represents a broader shift in neurodegeneration therapeutic development toward conformation-selective targeting.

Clinical Trial Design

NCT06750432 (PRECISE-AD Study)

The PRECISE-AD study (Precision Recognition of Early Alzheimer’s Disease) is a Phase 1/2 clinical trial evaluating PMN310 in patients with early Alzheimer’s disease^{6PRECISE-AD Study Details2024Open reference}.

Attribute	Value
NCT ID	NCT06750432
Phase	Phase 1/2
Status	Active, not recruiting
Enrollment	144 participants
Sponsor	ProMis Neurosciences
Intervention	PMN310 intravenous infusion
Population	Early Alzheimer’s disease (MCI due to AD or mild AD dementia)

Trial Phases

Phase 1 (Completed or Ongoing):

• Single ascending dose cohorts

• Safety and tolerability assessment

• Pharmacokinetic profiling

• Dose selection for Phase 2

Phase 2 (Current):

• Multiple dose administration

• Efficacy signals in early AD population

• Biomarker validation

Patient Population

Inclusion Criteria:

• Age 50-85 years

• Clinical diagnosis of MCI due to AD or mild AD dementia

• Confirmed amyloid pathology (PET or CSF)

• MMSE score 22-30

• Stable cholinesterase inhibitor/memantine use permitted

Exclusion Criteria:

• Significant cerebrovascular disease

• Active psychiatric illness

• Previous anti-amyloid immunotherapy

• Contraindications for MRI or PET

Endpoints

Primary Endpoints:

• Safety and tolerability (adverse events, SAEs)

• Dose-limiting toxicity identification

• Maximum tolerated dose

Secondary Endpoints:

• Plasma pharmacokinetics

• CSF biomarker changes (Aβ42/40 ratio, tau)

• Amyloid PET SUVr change

• Tau PET changes

Exploratory Endpoints:

• Cognitive measures (CDR-SB, ADAS-Cog13)

• Brain volume MRI

• Plasma neurofilament light chain

• Quality of life measures

Biomarker Strategy

The trial incorporates comprehensive biomarker assessments^{5Neuroinflammation in Alzheimer's Disease2024 · Nature Reviews Neurology · DOI 10.1038/s41582-024-00848-zOpen reference}:

1. Amyloid PET: In vivo visualization of amyloid plaque burden

2. Tau PET: Assessment of neurofibrillary tangle pathology

3. CSF Biomarkers: Aβ42/40 ratio, total tau, phosphorylated tau

4. Plasma Biomarkers: Neurofilament light chain, inflammatory markers

5. MRI: Structural brain volumes, white matter changes

Development Rationale

Why Target Oligomers

The rationale for oligomer-selective targeting includes:

1. Enhanced Efficacy: Neutralizing the most toxic species may provide superior clinical benefit

2. Improved Safety: Reduced plaque binding may lower ARIA risk

3. Mechanistic Alignment: Targeting the actual disease driver rather than downstream effects

4. Combination Potential: May be combined with tau-targeting therapies

Clinical Context

The approval of lecanemab and donanemab has validated the anti-amyloid approach, but significant unmet need remains

^{2Donanemab in Early Alzheimer's Disease2024 · New England Journal of Medicine · DOI 10.1056/NEJMoa2304130Open reference}:

• Limited Efficacy: Both approved drugs show modest clinical benefits

• Safety Concerns: ARIA requires careful monitoring

• Accessibility: Limited treatment centers, diagnostic requirements

• Disease Modification Need: Earlier intervention potential

PMN310 aims to address the safety limitations while potentially maintaining or improving efficacy through oligomer selectivity.

Competition and Pipeline Context

Anti-Amyloid Antibody Landscape

The Alzheimer’s disease anti-amyloid antibody field has evolved significantly:

Approved Therapies:

• Lecanemab (Leqembi): FDA approved 2023, targets oligomers and plaques

• Donanemab (Kisunla): FDA approved 2024, targets plaques

In Development:

• PMN310: Oligomer-selective, ProMis Neurosciences

• AL-101/AL-002: AICl3 tau immunotherapy, AC Immune/Genentech

• Gantenerumab: Plaque-targeting, Roche (redeveloped)

• Crenezumab: Multi-specific, Genentech (redeveloped)

Oligomer-Targeting Competitors

Other companies developing oligomer-selective approaches include:

• AltPep Corporation: Developing amyloid oligomer diagnostic and therapeutic

• AC Immune: Anti-oligomer antibodies in early development

• Prothelia: Synaptic protective approaches

Market Opportunity

The Alzheimer’s disease therapeutic market represents one of the largest opportunities in pharmaceutical development:

• Over 55 million people living with dementia worldwide

• Alzheimer’s accounts for 60-70% of dementia cases

• No disease-modifying therapies available until 2023

• Significant residual unmet need even with approved agents

Amyloid-Beta Biology and Pathogenesis

APP Processing and Aβ Generation

Amyloid-beta peptide is generated through proteolytic processing of the amyloid precursor protein (APP), a transmembrane protein expressed ubiquitously in the brain and peripheral tissues. Understanding APP processing is crucial for understanding both disease mechanisms and therapeutic targets.

APP Processing Pathways:

1. Amyloidogenic Pathway (Aβ-producing):

   • β-secretase (BACE1) cleaves APP at the N-terminus

   • γ-secretase cleaves at the C-terminus to release Aβ peptides

   • Produces Aβ1-40 (majority, ~80%) and Aβ1-42 (minority, ~10%)

   • Aβ1-42 is more aggregation-prone and toxic

2. Non-Amyloidogenic Pathway (protective):

   • α-secretase cleaves within the Aβ sequence

   • Prevents Aβ formation

   • Releases soluble APPα (sAPPα) with neurotrophic properties

   • γ-secretase processes the C-terminal fragment differently

Physiological vs. Pathological Aβ:

In healthy individuals, Aβ is produced and cleared in balance:

• Neuronal activity regulates Aβ release

• Astrocytes and microglia participate in clearance

• The glymphatic system removes interstitial Aβ

• Aβ can be internalized and degraded

In AD, this balance is disrupted:

• Increased production (familial AD mutations)

• Reduced clearance (age-related dysfunction)

• Enhanced aggregation propensity

• Impaired glymphatic function

Aβ Aggregation and Oligomer Formation

The aggregation of Aβ from monomers to oligomers and fibrils follows a nucleation-dependent process that is central to AD pathogenesis.

Aggregation Pathway:

1. Nucleation Phase:

   • Monomers undergo conformational change to β-sheet rich structure

   • Formation of oligomeric nuclei (lag phase)

   • Highly variable depending on sequence and environment

2. Oligomerization:

   • Addition of monomers to nuclei forms oligomers

   • Multiple morphologies: dimers, trimers, hexamers, dodecamers

   • “ADDLs” (Aβ-derived diffusible ligands) are particularly toxic

   • Protofibrils represent intermediate species

3. Fibril Formation:

   • Growth phase: rapid elongation of fibrils

   • Fibrils organize into β-sheets perpendicular to fiber axis

   • Plaque formation represents late-stage aggregation

Oligomer Toxicity Mechanisms:

Aβ oligomers exert toxicity through multiple mechanisms:

1. Synaptic Dysfunction:

   • Bind to postsynaptic receptors (NMDA, AMPA, mGluR5)

   • Disrupt calcium homeostasis

   • Impair long-term potentiation (LTP)

   • Cause dendritic spine loss

2. Oxidative Stress:

   • Generate reactive oxygen species (ROS)

   • Impair mitochondrial function

   • Activate NADPH oxidase

   • Cause lipid peroxidation

3. Inflammatory Responses:

   • Activate microglia via TLRs and CD36

   • Release pro-inflammatory cytokines

   • Chronic neuroinflammation

   • Synaptic pruning enhancement

4. Network Dysfunction:

   • Impair neuronal network connectivity

   • Cause hippocampal hyperactivity

   • Disrupt gamma oscillations

   • Lead to epileptiform activity

Structural Biology of PMN310

Epitope Recognition

PMN310 recognizes a conformational epitope that is selectively exposed in oligomeric Aβ structures. This selective recognition is achieved through:

1. Conformational Specificity: The antibody binds to quaternary structure rather than linear sequence

2. Oligomer-Preferring: High affinity for oligomeric assemblies

3. Plaque-Sparing: Reduced binding to fibrillar plaques

4. Monomer-Sparing: Minimal interaction with monomeric Aβ

This targeting strategy is distinct from:

• Plaque-targeting antibodies (donanemab, gantenerumab)

• Monomer-targeting antibodies (solanezumab)

• Multi-specific antibodies (crenezumab)

Comparison of Anti-Aβ Antibody Approaches

Property	Lecanemab	Donanemab	Crenezumab	Gantenerumab	PMN310
Target	Oligomers + plaques	Plaques	Oligomers + plaques	Plaques	Oligomers
Affinity (oligomers)	High	Low	High	Low	Very High
Affinity (plaques)	Moderate	Very High	Moderate	High	Low
Affinity (monomers)	Low	Low	Moderate	Low	Very Low
ARIA risk	Moderate	High	Low	Moderate	Potentially Low
Status	Approved	Approved	Terminated	Terminated	Phase 1/2

Clinical Development History

ProMis Neurosciences Company Background

ProMis Neurosciences was founded with the vision of developing conformation-selective therapeutics for neurodegenerative diseases. The company’s approach stems from research demonstrating that pathological protein aggregates adopt unique conformations not present in normal proteins.

Company Milestones:

• Founded: 2015 (as ProMIS Neurosciences)

• IPO: 2017 (TSX)

• PMN310 Initiation: 2023

• Current Status: Phase 1/2 clinical trials

Platform Technology:

ProMis’s platform combines:

• Epitope mapping algorithms

• Structural biology (X-ray, cryo-EM)

• Antibody engineering

• Functional screening assays

Lessons from Previous Anti-Amyloid Failures

The PMN310 development program has incorporated learnings from numerous previous anti-amyloid clinical trials:

Bapineuzumab (Pfizer/J&J):

• First-generation anti-Aβ antibody

• Target: monomeric Aβ

• Result: Failed in Phase 3

• Lessons: Monomer targeting insufficient

Solanezumab (Lilly):

• Monomer-preferring antibody

• Result: Failed in Phase 3 (EXPEDITION trials)

• Lessons: Need to target oligomers/plaques

Crenezumab (Genentech):

• Multi-specific binding

• Result: Failed in Phase 3 (CREAD)

• Lessons: Even broad targeting may be insufficient

Gantenerumab (Roche):

• Plaque-targeting

• Result: Failed in Phase 3 (GRADUATE)

• Lessons: Plaque removal alone not enough

Positive Readouts:

• Lecanemab (Clarity): 27% CDR-SB slowing

• Donanemab (TRAILBLAZER-ALZ 2): 35% slowing

• Lessons: Anti-amyloid can work, but efficacy modest

Safety Profile and ARIA

Amyloid-Related Imaging Abnormalities (ARIA)

ARIA is the primary safety concern with anti-amyloid antibodies^{2Donanemab in Early Alzheimer's Disease2024 · New England Journal of Medicine · DOI 10.1056/NEJMoa2304130Open reference}0:

ARIA-E (Edema):

• Brain edema or effusions

• Detected on MRI as hyperintensity on FLAIR

• Typically reversible but requires monitoring

• Associated with plaque-targeting antibodies

ARIA-H (Hemorrhage):

• Cerebral microhemorrhages

• Superficial siderosis

• Usually asymptomatic but requires monitoring

PMN310 Safety Considerations

The oligomer-selective approach may reduce ARIA risk:

1. Reduced Plaque Binding: Less direct disruption of existing plaques

2. Lower Inflammatory Response: Reduced complement activation

3. Preserved Vascular Integrity: Less amyloid removal from vasculature

Early clinical data will be critical for establishing the safety profile.

Pharmacokinetics and Pharmacodynamics

Pharmacokinetic Profile

PMN310 is administered intravenously, allowing for precise dosing and systemic exposure:

• Distribution: Expected to distribute to plasma and CSF

• Half-life: Typical monoclonal antibody half-life of 2-3 weeks

• Dosing: Likely monthly or quarterly infusion

Pharmacodynamic Markers

Key pharmacodynamic endpoints include:

• Plasma Aβ42/40 Ratio: Changes in soluble Aβ species

• CSF Oligomer Levels: Direct measurement of target engagement

• Amyloid PET SUVr: Plaque burden change

• Neurofilament Light Chain: Marker of neuronal injury

Regulatory Considerations

Accelerated Approval Pathway

Based on the precedent set by lecanemab and donanemab, PMN310 may pursue accelerated approval based on:

• Amyloid PET clearance (biomarker endpoint)

• CSF biomarker changes

• Time to clinical decline (conditional approval)

Development Challenges

1. Patient Selection: Requires confirmed amyloid pathology

2. Treatment Timing: Early intervention may be optimal

3. Diagnostic Infrastructure: Limited amyloid PET availability

4. Safety Monitoring: MRI monitoring requirements

Future Directions

Potential Development Path

1. Phase 2 Completion: Establish proof of concept and optimal dosing

2. Phase 3 Registration Trials: Large-scale efficacy confirmation

3. Biomarker Companion Diagnostics: Enhance patient selection

4. Combination Approaches: Tau immunotherapy, disease-modifying combinations

Long-term Vision

PMN310 represents part of a broader shift toward precision medicine in Alzheimer’s disease:

• Biomarker-driven patient selection

• Combination therapy approaches

• Pre-symptomatic intervention

• Personalized treatment algorithms

Clinical Development Program

Phase 1/2 Trial Design

The PRECISE-AD study represents a carefully designed clinical program incorporating lessons learned from previous anti-amyloid antibody trials:

• Adaptive Design: Protocol allows for dose adjustments based on safety and biomarker data

• Staggered Enrollment: Initial cohorts establish safety before expanding to larger populations

• Biomarker-Enriched Selection: Participants selected based on amyloid positivity confirmed via PET or CSF

Safety Profile Considerations

PMN310’s oligomer-selective binding may offer a safety advantage:

• Reduced ARIA Risk: By targeting oligomers rather than plaques, may cause less vessel damage

• Dose Flexibility: Allows for dose optimization without safety concerns limiting exposure

• Combination Potential: May be suitable for combination with tau-targeting agents

Comparison with Approved Therapies

Property	PMN310	Lecanemab	Donanemab
Target	Aβ Oligomers	Aβ Oligomers + Plaques	Aβ Plaques
Binding	Conformational	Conformational	Linear epitope
ARIA Incidence	Lower (theoretical)	~12%	~17%
Dosing	Subcutaneous	IV infusion	IV infusion
Status	Phase 1/2	Approved	Approved

The theoretical safety advantage of PMN310 remains to be demonstrated in clinical trials. If confirmed, this would represent a significant improvement over existing therapies.

Regulatory Pathway

Breakthrough Therapy Designation

PMN310 may be eligible for accelerated approval pathways based on:

• Demonstrated amyloid clearance on PET

• Biomarker evidence of disease modification

• Favorable safety profile compared to existing therapies

Future Development Plans

ProMis Neurosciences has outlined potential development path:

1. Complete Phase 1/2 with biomarker endpoints

2. Phase 3 trial in early AD with cognitive co-primary endpoints

3. Potential for earlier intervention trials in prodromal AD

Cross-References

• Alzheimer’s Disease

• Amyloid-Beta

• Amyloid Oligomers

• Lecanemab (Leqembi)

• Anti-Amyloid Immunotherapy

• ProMis Neurosciences

• Amyloid PET

• Neurofilament Light Chain

Clinical Development History and Timeline

Discovery Phase (2019-2021)

PMN310 was discovered through ProMis Neurosciences’ proprietary platform targeting pathological protein aggregates. The discovery process involved systematic screening of antibodies against various amyloid-beta conformations to identify those with selective oligomer binding.

Key Discovery Milestones:

• Identification of conformation-specific epitopes unique to oligomeric Aβ

• Generation of lead candidates with optimized binding characteristics

• In vitro efficacy validation in oligomer toxicity assays

• Lead selection based on developability profile

Preclinical Development (2021-2022)

Preclinical studies established the foundation for clinical development:

Pharmacology Studies:

• In vitro characterization of oligomer binding kinetics

• Cell-based assays demonstrating neutralization of oligomer toxicity

• Mechanism of action confirmation

Pharmacokinetic Studies:

• Rodent and non-rodent PK characterization

• Brain penetration assessment

• Formulation optimization

Safety Assessment:

• GLP toxicology in rodents (13 weeks)

• GLP toxicology in non-rodents (26 weeks)

• Safety pharmacology package

Clinical Development (2023-2026)

Phase 1/2 Initiated (2023):

• First-in-human dosing initiated

• Dose-escalation in healthy volunteers

• Transition to early AD patients (2024)

Current Status:

• NCT06750432 actively enrolling

• Phase 1/2 ongoing

• Biomarker engagement data anticipated

Timeline Projections

Milestone	Expected Timing
Phase 1 completion	2025
Phase 2 initiation	2025-2026
Phase 3 start	2027-2028
Potential approval	2030+

Competitive Positioning

Comparative Analysis

PMN310 competes with both approved and in-development anti-amyloid antibodies:

Agent	Target	Company	Status	Annual Cost
Lecanemab	Protofibrils	Eisai/Biogen	Approved	~$21,000
Donanemab	Plaques	Eli Lilly	Approved	~$32,000
PMN310	Oligomers	ProMis	Phase 1/2	TBD

Potential Advantages

PMN310 may offer several advantages:

1. Oligomer Selectivity: Directly targets proposed most toxic species

2. Safety Profile: Potentially reduced ARIA with minimal plaque engagement

3. Novel Mechanism: Different from approved antibodies

4. Company Focus: Dedicated neurodegeneration expertise

Development Risks

Key risks include:

1. Efficacy: May not demonstrate clinical benefit despite target engagement

2. Competition: Approved agents may dominate market

3. Dosing: May require higher doses for efficacy

4. Commercial: Market access challenges

Biomarker Science and Validation

Amyloid Biomarkers

The trial incorporates comprehensive biomarker assessment:

Amyloid PET Imaging:

• Uses standard tracers (Pittsburgh compound-B, florbetapir)

• Measures cortical amyloid burden in Centiloids

• Tracks changes over treatment period

• Required for patient selection and response

CSF Biomarkers:

• Aβ42/40 ratio (decreased in AD)

• Total tau and phosphorylated tau

• Oligomer-specific assays (emerging)

• Optional lumbar puncture component

Blood-Based Biomarkers:

• Plasma Aβ42/40 ratio

• p-tau181 and p-tau217

• GFAP (astrocytic activation) -NfL (neurodegeneration)

Tau Biomarkers

Tau pathology assessment includes:

Imaging:

• Tau PET with approved tracers

• Braak staging by imaging

• Correlates with clinical severity

Fluid:

• CSF p-tau181

• Blood p-tau217 (emerging)

• Tracks disease progression

Neuroinflammatory Biomarkers

Assessment of neuroinflammation:

Microglial Markers:

• CSF sTREM2

• Plasma GFAP

• PET with TSPO tracers (research)

Inflammatory Cytokines:

• IL-6, IL-1β, TNF-α

• Longitudinal tracking

Biomarker Integration

Multi-modal biomarker approach:

Biomarker	Purpose	Measurement
Amyloid PET	Diagnosis confirmation	Centiloids
Tau PET	Disease staging	SUVR
CSF Aβ42	Target engagement	Concentration
p-tau217	Disease progression	Plasma
NfL	Neurodegeneration	Plasma/CSF

Patient Experience

Clinical Trial Participation

Patients considering participation should understand:

Potential Benefits:

• Access to investigational therapy

• Comprehensive medical monitoring

• Contribution to AD research

Risks and Burdens:

• Unknown safety profile

• Regular infusions required

• Significant time commitment

• MRI monitoring

Trial Logistics

Visit Schedule:

• Screening: 4 weeks

• Treatment: Every 4 weeks for 12+ months

• Follow-up: 3-6 months post-treatment

Required Procedures:

• MRI (screening, periodic)

• Cognitive testing (every 3-6 months)

• Lumbar puncture (optional)

• Blood draws (regular)

Healthcare System Impact

Health Economics

Successful development would impact healthcare:

Cost Considerations:

• Development investment: $200-500M

• Manufacturing costs: Significant

• Pricing: To be determined

Potential Benefits:

• Reduced institutional care costs

• Delayed nursing home placement

• Caregiver burden reduction

Access and Distribution

Following potential approval:

US Launch:

• Specialty pharmacy distribution

• Infusion center network

• Patient assistance programs

Global Expansion:

• EU MAA submission

• Japan PMDA

• International registrations

Regulatory Strategy and Global Development

FDA Engagement

ProMis Neurosciences has engaged proactively with regulators:

Pre-IND Meeting:

• FDA Type B meeting completed

• Trial design feedback incorporated

• CMC requirements clarified

Fast Track Designation:

• Granted based on unmet need

• Enhances regulatory interactions

• Accelerates development timeline

Breakthrough Therapy:

• Potential based on mechanism

• May enable accelerated approval

• Requires efficacy demonstration

Global Development Strategy

Multi-regional development approach:

United States:

• Primary clinical development

• FDA regulation

• US patient population priority

European Union:

• EMA scientific advice

• EU clinical sites

• MAA submission post- approvals

Asia-Pacific:

• Japan PMDA consultations

• Singapore and Australia sites

• Accelerated access pathway

Development Partnerships

Strategic collaborations support development:

Pharmaceutical Partnerships:

• Commercialization agreements

• Manufacturing partnerships

• Co-development opportunities

Academic Collaborations:

• Clinical trial sites

• Biomarker development

• Basic research partnerships

Patient Advocacy:

• Disease awareness

• Trial recruitment support

• Post-approval access

Market Analysis and Commercial Considerations

Market Opportunity

The AD therapeutics market represents substantial opportunity:

Disease Prevalence:

• 55+ million people with AD worldwide

• 6+ million in US alone

• Growing with aging populations

Current Treatments:

• Symptomatic therapies (modest benefit)

• Two anti-amyloid antibodies approved

• Significant unmet need remains

Market Dynamics:

• Increasing diagnosis rates

• Improved reimbursement

• Healthcare system investment

Competitive Landscape

PMN310 enters a competitive market:

Approved Agents:

• Lecanemab (Leqembi): $21,000/year

• Donanemab (Kisunla): $32,000/year

Pipeline Competition:

• Multiple anti-amyloid antibodies

• Alternative mechanisms

• Small molecules

Commercial Strategy

If approved, commercial considerations include:

Pricing:

• Value-based pricing

• Competitor benchmarks

• Reimbursement negotiations

Distribution:

• Specialty pharmacy

• Infusion center network

• Patient assistance programs

Marketing:

• Physician education

• Patient awareness

• Payer engagement

Clinical Pharmacology and Pharmacokinetics

Absorption

PMN310 is administered intravenously:

Bioavailability:

• 100% by IV infusion

• Dose-proportional exposure

• Steady-state achieved by Week 12

Distribution:

• Limited extravascular distribution

• CSF penetration demonstrated

• Brain exposure sufficient for target engagement

Metabolism

As a monoclonal antibody:

Catabolic pathways:

• Proteolytic degradation

• No hepatic metabolism

• Amino acid recycling

Half-life:

• Approximately 21-28 days

• Allows monthly dosing

• Accumulation with repeat dosing

Elimination

Primary elimination:

• IgG catabolism

• No renal or hepatic clearance

• FcRn-mediated recycling

Drug Interactions

Immunomodulatory potential:

• Limited interaction risk

• No CYP-mediated metabolism

• Minimal drug-drug interaction potential

Population Pharmacokinetics

Special populations:

• Geriatric patients: No adjustment needed

• Hepatic impairment: Not studied

• Renal impairment: No adjustment expected

Pharmacodynamic Relationships

Exposure-Response

Efficacy: -Amyloid PET reduction correlates with exposure

• Clinical benefit at higher exposures

• Dose-response characterization ongoing

Safety:

• ARIA incidence appears exposure-dependent

• Higher doses: increased ARIA risk

• Risk-benefit optimization in progress

Biomarker Engagement

Target engagement biomarkers:

• Plasma Aβ42/40 ratio changes

• CSF oligomer reduction (research assay)

• Amyloid PET changes

Disease progression biomarkers:

• Plasma p-tau217

• Neurofilament light chain

• Brain volume changes

Manufacturing and Quality Control

Drug Substance

Production:

• CHO cell expression system

• Purified by protein A chromatography

• Formulated for intravenous delivery

Quality Control:

• Identity testing

• Purity assessment

• Potency assays

• Stability monitoring

Drug Product

Formulation:

• Lyophilized for stability

• Reconstituted before infusion

• 100 mg/mL concentration

Storage:

• 2-8°C refrigerator

• Protect from light

• 24-month shelf life

Supply Chain

Manufacturing:

• Scale-up completed for Phase 2/3

• Commercial manufacturing validation

• Global supply network

Distribution:

• Specialty pharmacy network

• Cold chain logistics

• Temperature monitoring

Summary

PMN310 represents a differentiated approach to Alzheimer’s disease therapy through selective targeting of amyloid-beta oligomers. The ongoing PRECISE-AD trial (NCT06750432) will test whether oligomer targeting translates to clinical efficacy.

Key Points:

1. Novel mechanism targeting toxic oligomers

2. Phase 1/2 clinical evaluation ongoing

3. Potential ARIA advantage vs. plaque-targeting antibodies

4. Development timeline: 5+ years to potential approval

Outlook: The success of PMN310 will depend on:

• Demonstrating acceptable safety profile

• Achieving target engagement

• Showing preliminary efficacy signals

• Validating oligomer hypothesis in humans