A Study of Tolerability and Efficacy of Cannabidiol on Tremor in Parkinson's Disease

The major purpose of the Stage 1 is to study the safety and tolerability of the proposed dosage regimen of the study drug. The form of cannabidiol (CBD) used in this study is GWP42003, supplied by GW Pharmaceuticals. The dosage regime is based on their experience. This is an open label study in 10 subjects, during which the dose is gradually increased to the manufacturers recommended target dose, with tolerability being evaluated at each dose level. Based on the response of subjects in the Stage 1, a target dose is determined for the next stage. Standardized tools will be administered to study both tolerability and efficacy. Efficacy assessments are simply explorative, and are done to look for an effect that warrants specific or different evaluation in the next stage.