Ascending Dose Tolerability/Safety of SLV308 for the Treatment of Parkinson's Disease

A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Ascending Dose, Parallel Group Study Exploring Effects of SLV308 up to 42 mg/Day Administered as an Adjunctive Therapy to L-Dopa in Patients With Advanced Stage Parkinson's Disease

This study is a multicenter, randomized, double-blind, placebo controlled, parallel group study of a seven-week ascending dose period of SLV308 adjunctive to L-dopa treatment in patients with advanced stage Parkinson's disease (PD) and dose-dependent motor fluctuations. Patients (outpatients) will be randomized to one of three different treatment arms.

Inclusion Criteria:

• Patients who have signed an informed consent; diagnosis of idiopathic PD.
• Presence of recognizable "on" and "off" stages
• Minimum hours of "off" time per day of 2.5 hours
• Able to keep diaries.

Exclusion Criteria:

• Unclear diagnosis or a suspicion of other parkinsonian syndromes
• Have undergone surgical treatment for PD
• History of non-response to L-dopa.