Buspirone, in Combination With Amantadine, for the Treatment of Levodopa-induced Dyskinesia

Plan: We will perform a randomized, placebo-controlled, double-blind, two-period cross-over
study to evaluate the safety, tolerability, and efficacy of a novel treatment combination for
LID in PD.

Methods: Eligible subjects who consent to participate in this study will be randomized to one
of two sequences of treatment interventions during the baseline visit. Each treatment
sequence includes placebo and buspirone interventions. After randomization, each participant
will titrate up on study drug for two weeks ending in 30 mg/day. At the end of each two week
study drug period, the participant will then have a study visit at the VA Portland Health
Care System that includes safety monitoring, adverse event monitoring, drug compliance, and
several measurements of LID.

Inclusion Criteria:

- Parkinson's disease diagnosis

- Currently taking a levodopa containing medication for Parkinson's disease

- Mild to Severe dyskinesia

- Currently taking between 200-500 mg of amantadine daily for treatment of
levodopa-induced dyskinesia with insufficient suppression levodopa-induced dyskinesia.

- Stable medication regimen for at least 4 weeks prior to study.

Exclusion Criteria:

- Currently receiving any other treatment for levodopa-induced dyskinesia, including but
not exclusive to deep brain stimulation.

- Not able to follow verbal commands

- Not able to stand unsupported for at least 60 seconds

- Not able to answer a patient questionnaire about their symptoms of Parkinson's disease
and dyskinesia.

- Have proprioceptive deficits.

- Have a history of hepatic impairment

- Currently have severe renal impairment

- Currently have any other medical or psychiatric diagnosis that would preclude their
ability to safely participate in the study.

- Significant cognitive impairment

- Pregnancy

- Breast-Feeding

- Unable to swallow study drug (capsule)