Denali Therapeutics has announced positive results from its first-in-human LRRK2 inhibitor clinical trial. The trial concluded that the experimental treatment is safe, and showed a greater than 90 percent inhibition of LRRK2 activity at peak drug levels while lowered the LRRK2 protein activity in human body cells. This is a meaningful milestone in the clinical development of a drug with the potential to slow or stop Parkinson’s progression.

Denali also announced that it has commenced dosing of its second small molecule inhibitor of LRRK2, DNL151, in healthy volunteers in the Netherlands. Denali now has two distinct small molecules targeting LRRK2 inhibition in human clinical testing for Parkinson’s disease.

Denali plans to select either DNL201 or DNL151 to move into studies in Parkinson’s disease patients carrying a LRRK2 mutation after completion of Phase 1 healthy volunteer studies for both molecules. In the ongoing studies in healthy volunteers, Denali is investigating safety and tolerability, PK and PD in blood and CSF, and characterizing a biomarker to estimate target engagement in the brain.

“Mutations in LRRK2 are a major risk factor for Parkinson’s disease. Targeting this degenogene represents a promising approach to develop disease modifying medicines for patients suffering from this terrible disease,” said Ryan Watts, Ph.D., CEO. “By restoring LRRK2 activity to normal levels, we believe we can reverse lysosomal dysfunction, which could potentially benefit both patients with LRRK2 mutations, as well as idiopathic Parkinson’s disease patients who exhibit lysosomal dysfunction,” said Dr. Watts.