Prothena Corporation plc

Prothena Corporation

Overview

Prothena Corporation

Overview

Prothena Corporation is an American biotechnology company headquartered in South San Francisco, California, focused on the development of novel protein immunotherapy for the treatment of various diseases, including [Alzheimer's disease](/diseases/alzheimers-disease), [Parkinson's disease](/diseases/parkinsons-disease), and amyloidosis. [@prothena]

Company Overview

| Attribute | Details | [@prasinezumab2022]
|-----------|---------| [@roche]
| Ticker | NASDAQ: PRTA | [@prx2023]
| Headquarters | South San Francisco, California, USA |
| Founded | 2005 (as a spinout from Elan) |
| CEO | Hideki (Gene) |
| Employees | ~100 |
| Market Cap | ~$600 million (2024) |

Alzheimer's Disease Pipeline

Lead Program: Prasinezumab

| Drug | Mechanism | Phase | Indication |
|------|-----------|-------|------------|
| Prasinezumab | Anti-[alpha-synuclein](/proteins/alpha-synuclein) mAb | Phase 2 | Parkinson's disease (with AD) |
| PRX012 | Anti-amyloid beta mAb | Phase 1 | Alzheimer's disease |
| PRX031 | - | Discovery | Alzheimer's disease |

Prasinezumab (PRX002)

• Mechanism: Monoclonal antibody targeting alpha-synuclein
• Target: Alpha-synuclein (precursor protein)
• Phase: Phase 2 (PASADENA study completed, SPARK)
• Partner: Roche (global development and commercialization)
• Clinical Trials: [PASADENA](https://clinicaltrials.gov/show/NCT03100149), [SPARK](https://clinicaltrials.gov/show/NCT03744390)
• Results: Did not meet primary endpoint in PASADENA but showed slowing of motor progression

PRX012

• Mechanism: Anti-amyloid beta monoclonal antibody
• Target: [Amyloid-beta](/proteins/amyloid-beta) plaques
• Phase: Phase 1 (completed)
• Status: Advanced to Phase 2 planning

Parkinson's Disease Pipeline

| Drug | Mechanism | Phase | Indication |
|------|-----------|-------|------------|
| Prasinezumab | Anti-alpha-synuclein mAb | Phase 2 | PD |
| PRX005 | Anti-tau mAb | Phase 1 | PD |
| Degrasppoon Program | CDR-based protein degrader | Discovery | PD |

Degrasppoon Platform (Emerging)

Prothena is developing a novel protein degradation platform based on CDR-derived degrasppoons. These are designed to selectively recruit disease-causing proteins to the proteasome for degradation. This approach offers potential advantages over traditional antibodies by intracellularly degrading targets rather than just neutralizing them[@prothena].

Approach:

• Uses complementarity-determining regions (CDRs) from antibodies as targeting modules
• Fuses CDRs to E3 ligase recruitment domains
• Achieves targeted protein degradation of pathological species
• Potential for tau, alpha-synuclein, and other targets

Prasinezumab for Parkinson's

• Rationale: Alpha-synuclein is a key protein in PD pathogenesis; antibodies may prevent spreading of pathological forms
• Key Trials: SPARK (Phase 2, ongoing)

PRX005

• Mechanism: Anti-tau monoclonal antibody
• Target: [Tau protein](/proteins/tau)
• Phase: Phase 1
• Rationale: Target tau pathology in Parkinson's disease

Amyloidosis Pipeline

| Drug | Mechanism | Phase | Indication |
|------|-----------|-------|------------|
| BIRZRA | Anti-amyloid mAb | Phase 1 | AL amyloidosis |

BIRZRA (Prothena-developed)

• Mechanism: Monoclonal antibody targeting amyloid deposits
• Target: Amyloid fibrils
• Phase: Phase 1

Strategic Partnerships

Roche Partnership

• Scope: Global development and commercialization of prasinezumab
• Structure: Roche leads clinical development and commercialization; Prothena receives milestones and royalties
• Deal Value: $600M+ in milestones

Bristol Myers Squibb Partnership

• Scope: Protein degradation platform (formerly)
• Status: Terminated (2023)

Financial Highlights

| Year | Revenue | Cash | Key Programs |
|------|---------|------|--------------|
| 2023 | $45M | $400M | Prasinezumab, PRX012 |
| 2022 | $30M | $420M | Prasinezumab |
| 2021 | $25M | $450M | Prasinezumab |

Key Leadership

• Hideki (Gene) - CEO
• Wagner - Chief Medical Officer
• Diskin - Co-founder

Related Companies

• [Biogen](/companies/biogen) - Major player in AD/PD
• [Eli Lilly](/companies/eli-lilly) - AD pipeline competitor
• [Roche](/companies/roche) - Neuroscience pipeline
• [Eisai](/companies/eisai) - AD partnership with Biogen
• [Denali Therapeutics](/companies/denali) - Neurodegeneration focus

Funding and Financial History

Initial Public Offering

• IPO: December 2012 (NASDAQ: PRTA)
• Raised approximately $60 million in initial public offering
• Originally spun out from Elan Corporation

Major Financial Events

• 2013: Entered into collaboration with Roche for prasinezumab (PRX002)
• 2018: Bristol-Myers Squibb acquired Elan's stake in Prothena
• 2019: Sold remaining amyloid programs to Novo Nordisk ($50 million)
• 2020: Acquired certain assets from Onclave Therapeutics

Key Partnerships

• Roche: Global development and commercialization agreement for prasinezumab
• Deal value: $60 million upfront + $600 million in milestones
• Elan/Proteon: Original founding partnership and continued R&D support

Market Position

• Focused on protein immunotherapy for neurodegenerative diseases and amyloidosis
• Novel antibody platforms (RAP and TAB) for targeting misfolded proteins
• Pipeline spans AD, PD, and ATTR amyloidosis
• [Alzheimer's Disease](/diseases/alzheimers-disease) — Alzheimer's drug development
• [Parkinson's Disease](/diseases/parkinsons-disease) — Parkinson's drug development
• [Amyloid](/mechanisms/amyloid-aggregation) Cascade Hypothesis — Amyloid-targeting therapies
• [Tau](/proteins/tau) Pathology — Tau-targeting therapies
• Clinical Trials Overview — Clinical trial portfolio

External Links

• [ClinicalTrials.gov Search](https://clinicaltrials.gov/search?spons=Prothena)

References

Pathway Diagram

The following diagram shows the key molecular relationships involving Prothena Corporation plc discovered through SciDEX knowledge graph analysis: