Efficacy and Safety of Amantadine Hydrochloride (HCl) ER Tablets to Treat Parkinson's Disease Patients With LID.

This study was terminated early due to slow enrollment with 87 of 162 planned subjects enrolled. Amantadine has been used for many years as a treatment for Parkinson's disease. It has been reported in the literature to effectively treat the motor complications of levodopa, especially dyskinesia, but it must be given 2 to 4 times a day. The purpose of this multi-center, randomized, double-blind, parallel-group, 16 week study is to compare the efficacy and safety of two different dose levels of Amantadine Extended Release Tablets to placebo for the treatment of levodopa induced dyskinesia in patients with Parkinson's disease. The dose will be given once a day in the morning so that amantadine concentrations are maintained throughout the day for treating the levodopa induced dyskinesia, but will be lower during the night, potentially reducing the negative impact of amantadine on sleep.