A Placebo- and Active Controlled Study of Preladenant in Subjects With Moderate to Severe Parkinson's Disease (P04938)
Status:
Completed
Trial end date:
2012-12-20
Target enrollment:
Participant gender:
Summary
When a patient with Parkinson's disease (PD) is initially treated with L-dopa or dopamine
agonists, the symptoms of PD improve or disappear. After several years of taking L dopa or
dopamine agonists, patients notice that their PD medications wear off sooner than when they
first started taking them. This "wearing off" is characterized by the return of symptoms
(i.e., tremor, slowness, and rigidity) and may occur over the course of a few minutes to an
hour. When a patient's PD symptoms have returned, the patient is said to be in the "off"
state. When the patient takes another dose of medication, and his/her PD symptoms improve or
resolve, the patient is said to be in the "on" state. Antagonism of adenosine Type 2a
receptors (A2a) may provide relief of PD symptoms. This trial will test the hypothesis that
A2a receptor antagonism can lead to improvement in the function of PD participants taking a
stable dose of L-dopa, as measured by a reduction in "off" time.