This is a phase I study to assess the tolerability and safety of 4 injections of two different doses of AFFITOPE® PD01A formulated with an adjuvant to patients with early Parkinson's disease in male and female patients aged 45 to 65 years (or age between 40 and 45 years if there is no evidence for genetic forms of the disease and the diagnosis of idiopathic Parkinson's disease was confirmed, after approval by Sponsor). One study site in Vienna (Austria) will be involved. Each patient's participation will last 1 year.

In addition, up to 8 patients will be offered participation within an untreated control group.

Inclusion Criteria:

• Informed consent capability
• Early PD (≤ 4 years), Hoehn&Yahr Stages I/II and fulfill the UK Parkinson's Disease Society Brain Bank Criteria
• Brain magnetic resonance imaging (MRI) scan and DAT-SPECT scan are consistent with the diagnosis of PD
• Age between 45 and 65 years or age between 40 and 45 years if there is no evidence for genetic forms of the disease and the diagnosis of idiopathic PD was confirmed, after approval by Sponsor
• Caregiver able to attend all visits with patient
• Stable doses of medications (levodopa (+/- benserazide, carbidopa), COMT inhibitors (entacapone, tolcapone), non-ergot dopamine agonists (pramipexol, ropinirol, rotigotine), the MAO-B inhibitor rasagiline and amantadine are allowed)

Exclusion Criteria:

• Women of childbearing potential without birth control or pregnant women
• Participation in another clinical trial
• Autoimmune disease or allergy to components of the vaccine
• Contraindications for MRI, DAT-SPECT, colonoscopy including biopsy or lumbar puncture
• Dementia
• History of cancer (Exceptions: basal cell carcinoma, intraepithelial cervical neoplasia)
• Active infectious disease
• Immunodeficiency
• Significant systemic illness or psychiatric illness
• Parkinson-like disease secondary to drug therapy side effects
• Parkinson-plus syndromes
• Heredodegenerative disorders
• Alcoholism or substance abuse
• Prior treatment with experimental immunotherapeutics for PD including IVIG, with immunosuppressive drugs or treatment with deep brain stimulation
• Venous status rendering it impossible to place an i.v. access