Testing Experimental Parkinson's Disease Medication

Eligibility Details: Inclusion criteria: Healthy subjects: - Men and women ≥18 and ≤55 years of age with a body mass index (BMI) ≥18 and ≤32 kg/m2 (non-Japanese subjects) and ≥18 and ≤28 kg/m2 (Japanese subjects) Patients with Parkinson's disease: - Men and women with a clinical diagnosis of idiopathic Parkinson's disease, Hoehn and Yahn (H&Y, stage 1-3) - For a minimum of three months prior to enrolment, Parkinson's disease symptoms have been stable and is anticipated to be stable during the study duration as judged by the PI - If on Parkinson's disease treatment the dose must be stable for a minimum of three months prior to enrolment and is anticipated to be stable during the study duration as judged by the PI - ≥40 and ≤80 years of age - BMI ≥18 and ≤35 kg/m2 Exclusion criteria: - Atypical Parkinsonism - Clinically relevant structural brain abnormality, as assessed using MRI - Mild cognitive impairment, measured as a Montreal cognitive assessment (MoCA) score =<21 - Any past or current treatment with an active vaccine targeting alpha-synuclein - Any past or current treatment with a monoclonal antibody within the last 12 months Other in- and exclusion criteria may apply.