Parkinson’s disease destroys the nerve cells that make dopamine, a key player in nerve cell communication and involved in movement control, cognition, memory, learning, attention, and sleep.
Parkinson’s main affected brain area is the substantia nigra, which controls movement, but as the disease progresses and spreads in the brain, it can affect the areas responsible for mental functions, memory, and judgment.
About 50 percent of Parkinson’s patients will experience some form of cognitive impairment, which is diagnosed as Parkinson’s disease dementia when it affects more than one area of cognition and is severe enough to impair social or work functioning.
Symptoms of PDD can include attention difficulties, forgetfulness, and slow thought processes. This can make communication difficult, as remembering words and names and following conversations can be challenging.
Eli Lilly is developing LY3154207, an orally administered enhancer of dopamine receptor D1 — a type of dopamine receptor involved in cognition — for the treatment of PDD.
Previous preclinical studies have shown that enhancing dopamine receptor D1 can improve cognitive function, including attention.
In March 2017, a Phase 1 study (NCT02562768) evaluating LY3154207’s safety, tolerability, and how the body processes the therapy, was completed in healthy volunteers and Parkinson’s patients.
Now, a randomized placebo-controlled Phase 2 study called PRESENCE (NCT03305809) will evaluate the safety and effectiveness of three doses of LY3154207 in patients with mild-to-moderate Parkinson’s disease dementia.
Ely Lilly seeks to enroll 340 individuals, 46-85 years old, in centers from four countries: U.S., Canada, China, and Puerto Rico. Participants must have Parkinson’s disease with at least two years of symptoms, have PDD with a decline in cognitive function leading to functional impairment, have no history of a stroke in the past six months, and no signs/diagnosis of psychotic diseases.
Participants will be chosen randomly to receive daily either one of the three doses of LY3154207, or a placebo, for 12 weeks.
The study’s main goal is improvement in the ability to sustain concentration for a period of time without error — assessed through the Continuity of Attention (CoA) Composite Score of the Cognitive Drug Research Computerized Cognition Battery (CDR-CCB).
Secondary goals include improvements in cognitive function and attention, daytime sleepiness, dementia-related behavioral symptoms, activities of daily life, and motor function.
The PRESENCE study is estimated to conclude by July 2019.