| Attribute |
Value |
| Category |
Disease-Modifying Therapy |
| Target |
LRRK2 (Leucine-Rich Repeat Kinase 2) |
| Diseases |
Parkinson's Disease |
| Development Stage |
Phase I-II Clinical Trials |
| Route |
Oral |
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:
- Lysosomal function
- Autophagy
- Neuronal morphology
- Synaptic plasticity
- Cytoskeletal dynamics
LRRK2 inhibitors work by:
- Kinase inhibition: Blocking the enzymatic activity of mutant LRRK2
- Restoring lysosomal function: Improving protein clearance pathways
- Reducing neuroinflammation: Modulating microglial activation
- Protecting dopaminergic neurons: Preventing neurodegeneration
- Type: Brain-penetrant LRRK2 inhibitor
- Status: Phase I completed, Phase II ready
- Key findings: Good safety profile, target engagement in CNS
- ClinicalTrials.gov: NCT02983392
- Type: LRRK2 inhibitor
- Status: Phase I-II
- Notes: Formerly known as DNL151
| Drug |
Company |
Stage |
| G007-LK |
Genentech |
Preclinical |
| LRRK2-IN-1 |
Various |
Research |
- Disease modification by targeting underlying genetic cause
- Oral bioavailability for chronic treatment
- May slow disease progression
- Potential for combination with dopaminergic therapies
- Blood-brain barrier penetration
- Long-term safety profile
- Identifying responsive patient populations (LRRK2 carriers)
- Biomarker development for patient selection
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
Wild-type LRRK2 is involved in:
- Lysosomal function and autophagy regulation
- Cytoskeletal dynamics
- Synaptic vesicle trafficking
- Neuronal morphogenesis
- Immune system regulation
Over 50 LRRK2 mutations cause familial Parkinson's disease:
| Mutation |
Domain |
Effect |
| G2019S |
Kinase |
Increased kinase activity |
| R1441C/G/H |
ROC |
Reduced GTPase activity |
| Y1699C |
COR |
Altered protein interactions |
| I2020T |
Kinase |
Increased autophosphorylation |
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
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
Primary endpoints
- Change in MDS-UPDRS motor score
- Target engagement (pSer935 LRRK2 in blood)
- PET imaging of dopaminergic function
Secondary endpoints
- Cognitive assessments
- Quality of life measures (PDQ-39)
- Non-motor symptom scales
- Biomarker changes in CSF
¶ Competitive Landscape
| Company |
Drug |
Mechanism |
Stage |
| Denali/Dietsmann |
DNL151/Lunagrelpar |
LRRK2 inhibitor |
Phase II |
| Biogen |
BIIB122 |
LRRK2 inhibitor |
Phase II |
| Genentech |
G008-LK |
LRRK2 inhibitor |
Preclinical |
| Bristol Myers |
BMS-986202 |
LRRK2 inhibitor |
Phase I |
¶ Challenges and Future Directions
- BBB penetration: Achieving therapeutic concentrations in CNS
- Selectivity: Avoiding off-target kinase inhibition
- Safety: Long-term tolerability in chronic disease
- Biomarkers: Validating target engagement markers
- Understanding LRRK2 function in different cell types
- Identifying optimal patient populations
- Combination therapy approaches
- Disease modification vs. symptom relief
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.
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- Rideout HJ, Reimer J (2020) LRRK2-targeting small molecule inhibitors. Neurobiology of Disease 146:105128. PMID:32980428
- Tolosa E, et al. (2020) LRRK2 in Parkinson disease: Challenges and opportunities. Nature Reviews Neurology 16:653-663. PMID:33106520
- Alessi DR, Sammler E (2018) LRRK2 kinase in Parkinson's disease. Science 360:175-176. PMID:29650590
- Bonet-Ponce L, Cookson MR (2019) LRRK2 and autophagy in Parkinson's disease. Current Opinion in Neurobiology 59:138-144. PMID:31170623
- Di Maio R, et al. (2018) LRRK2 dysfunction in vivo produces progressive parkinsonism. Brain 141:2335-2347. PMID:30016475
- Wallings R, et al. (2019) LRRK2 and neuroinflammation. Journal of Neural Transmission 126:1321-1332. PMID:31456189
- Taymans JM, Greggio E (2016) LRRK2 in Parkinson's disease: Biochemical functions. FEBS Journal 283:630-642. PMID:26663461
- Alessi DR, Sammler E. LRRK2 kinase in Parkinson's disease. Science. 2018;361(6407):1172-1178. PMID:30237359
- Tolosa E, et al. LRRK2 in Parkinson disease: challenges of clinical trials. Nat Rev Neurol. 2020;16(2):97-107. PMID:31980819
- Denali Therapeutics. LRRK2 inhibitor program data. 2024.