LRRK2 Inhibitors for Parkinson's Disease

LRRK2 Inhibitors for Parkinson's Disease

Introduction

<table class="infobox infobox-therapeutic">
<tr>
<th class="infobox-header" colspan="2">LRRK2 Inhibitors for Parkinson's Disease</th>
</tr>
<tr>
<td class="label">Category</td>
<td>Disease-Modifying Therapy</td>
</tr>
<tr>
<td class="label">Target</td>
<td>LRRK2 (Leucine-Rich Repeat Kinase 2)</td>
</tr>
<tr>
<td class="label">Diseases</td>
<td>Parkinson's Disease</td>
</tr>
<tr>
<td class="label">Development Stage</td>
<td>Phase I-II Clinical Trials</td>
</tr>
<tr>
<td class="label">Route</td>
<td>Oral</td>
</tr>
<tr>
<td class="label">Drug</td>
<td>Company</td>
</tr>
<tr>
<td class="label">G007-LK</td>
<td>Genentech</td>
</tr>
<tr>
<td class="label">LRRK2-IN-1</td>
<td>Various</td>
</tr>
<tr>
<td class="label">Mutation</td>
<td>Domain</td>
</tr>
<tr>
<td class="label">G2019S</td>
<td>Kinase</td>
</tr>
<tr>
<td class="label">R1441C/G/H</td>
<td>ROC</td>
</tr>
<tr>
<td class="label">Y1699C</td>
<td>COR</td>
</tr>
<tr>
<td class="label">I2020T</td>
<td>Kinase</td>
</tr>
<tr>
<td class="label">Company</td>
<td>Drug</td>
</tr>
<tr>
<td class="label">Denali/Dietsmann</td>
<td>DNL151/Lunagrelpar</td>
</tr>
<tr>
<td class="label">Biogen</td>
<td>BIIB122</td>
</tr>
<tr>
<td class="label">Genentech</td>
<td>G008-LK</td>
</tr>
<tr>
<td class="label">Bristol Myers</td>
<td>BMS-986202</td>
</tr>
</table>

LRRK2 Inhibitors for Parkinson's Disease

Introduction

<table class="infobox infobox-therapeutic">
<tr>
<th class="infobox-header" colspan="2">LRRK2 Inhibitors for Parkinson's Disease</th>
</tr>
<tr>
<td class="label">Category</td>
<td>Disease-Modifying Therapy</td>
</tr>
<tr>
<td class="label">Target</td>
<td>LRRK2 (Leucine-Rich Repeat Kinase 2)</td>
</tr>
<tr>
<td class="label">Diseases</td>
<td>Parkinson's Disease</td>
</tr>
<tr>
<td class="label">Development Stage</td>
<td>Phase I-II Clinical Trials</td>
</tr>
<tr>
<td class="label">Route</td>
<td>Oral</td>
</tr>
<tr>
<td class="label">Drug</td>
<td>Company</td>
</tr>
<tr>
<td class="label">G007-LK</td>
<td>Genentech</td>
</tr>
<tr>
<td class="label">LRRK2-IN-1</td>
<td>Various</td>
</tr>
<tr>
<td class="label">Mutation</td>
<td>Domain</td>
</tr>
<tr>
<td class="label">G2019S</td>
<td>Kinase</td>
</tr>
<tr>
<td class="label">R1441C/G/H</td>
<td>ROC</td>
</tr>
<tr>
<td class="label">Y1699C</td>
<td>COR</td>
</tr>
<tr>
<td class="label">I2020T</td>
<td>Kinase</td>
</tr>
<tr>
<td class="label">Company</td>
<td>Drug</td>
</tr>
<tr>
<td class="label">Denali/Dietsmann</td>
<td>DNL151/Lunagrelpar</td>
</tr>
<tr>
<td class="label">Biogen</td>
<td>BIIB122</td>
</tr>
<tr>
<td class="label">Genentech</td>
<td>G008-LK</td>
</tr>
<tr>
<td class="label">Bristol Myers</td>
<td>BMS-986202</td>
</tr>
</table>

Overview

Mechanism of Action

LRRK2 (leucine-rich repeat kinase 2) is the most common genetic cause of Parkinson's disease, with mutations in the LRRK2 gene (particularly G2019S) causing approximately 5-10% of familial PD and 1-2% of sporadic PD cases. LRRK2 is a large multi-domain protein with GTPase and kinase activities that regulates various cellular processes including: [@taymans2016]

• Lysosomal function
• [Autophagy](/entities/autophagy)
• Neuronal morphology
• Synaptic plasticity
• Cytoskeletal dynamics

Clinical Development

DNL151 (Denali Therapeutics)

• Type: Brain-penetrant LRRK2 inhibitor
• Status: Phase I completed, Phase II ready
• Key findings: Good safety profile, target engagement in CNS
• ClinicalTrials.gov: NCT02983392

BIIB122 (Biogen/Denali)

• Type: LRRK2 inhibitor
• Status: Phase I-II
• Notes: Formerly known as DNL151

Other LRRK2 Inhibitors in Development

Therapeutic Implications

Potential Benefits

• Disease modification by targeting underlying genetic cause
• Oral bioavailability for chronic treatment
• May slow disease progression
• Potential for combination with dopaminergic therapies

Challenges

• [Blood-brain barrier](/entities/blood-brain-barrier) penetration
• Long-term safety profile
• Identifying responsive patient populations (LRRK2 carriers)
• Biomarker development for patient selection

LRRK2 Biology in Parkinson's Disease

Normal Function

LRRK2 (Leucine-Rich Repeat Kinase 2) is a large 2527-amino acid protein with multiple functional domains:

• Ankyrin repeat domain: Protein-protein interactions
• LRR domain: Leucine-rich repeats for substrate recognition
• ROC domain: GTPase activity (Ras of complex proteins)
• COR domain: C-terminal of ROC
• Kinase domain: Ser/Thr kinase activity

• Lysosomal function and autophagy regulation
• Cytoskeletal dynamics
• Synaptic vesicle trafficking
• Neuronal morphogenesis
• Immune system regulation

Pathogenic Mutations

Over 50 LRRK2 mutations cause familial Parkinson's disease:

The G2019S mutation (most common) increases kinase activity by ~40%, leading to:

• Enhanced phosphorylation of LRRK2 substrates
• Impaired autophagy-lysosomal function
• Increased neuronal vulnerability
• Microglial activation and neuroinflammation

Clinical Trial Design

Patient Selection

Key considerations for LRRK2 inhibitor trials:

• Genetic testing: Confirmation of LRRK2 mutation carriers
• Disease stage: Early-to-mid stage PD (Hoehn & Yahr 1-3)
• Motor symptoms: Stable dopaminergic therapy
• Biomarkers: Use of target engagement biomarkers

Outcome Measures

Primary endpoints

• Change in MDS-UPDRS motor score
• Target engagement (pSer935 LRRK2 in blood)
• PET imaging of dopaminergic function

• Cognitive assessments
• Quality of life measures (PDQ-39)
• Non-motor symptom scales
• Biomarker changes in CSF

Competitive Landscape

Pipeline Overview

Challenges and Future Directions

Technical Challenges

Research Priorities

• Understanding LRRK2 function in different cell types
• Identifying optimal patient populations
• Combination therapy approaches
• Disease modification vs. symptom relief

Background

The study of Lrrk2 Inhibitors For Parkinson'S Disease has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.

Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.

Allen Brain Atlas Resources

• [Allen Brain Atlas - Gene Expression](https://human.brain-map.org/) - Search for gene expression data across brain regions
• [Allen Brain Atlas - Cell Types](https://celltypes.brain-map.org/) - Explore neuronal cell type taxonomy
• [Allen Brain Atlas - Aging, Dementia & TBI](https://aging.brain-map.org/) - Data on aging and traumatic brain injury

Allen Brain Atlas Resources

• [Allen Brain Atlas - Gene Expression](https://human.brain-map.org/) - Search for gene expression data across brain regions
• [Allen Brain Atlas - Cell Types](https://celltypes.brain-map.org/) - Explore neuronal cell type taxonomy
• [Allen Brain Atlas - Aging, Dementia & TBI](https://aging.brain-map.org/) - Data on aging and traumatic brain injury

References

See Also

• [Parkinson's Disease](/diseases/parkinsons-disease)
• [LRRK2 Gene](/genes/lrrk2)
• [Dopaminergic Vulnerability Pathway](/entities/dopamine)
• [Alpha-Synuclein Aggregati- Mitochondrial Dysfunction Pathway](/proteins/alpha-synuclein)
• [Autophag](/companies/ad-autophagy-modulation-companies)