The objective of this Phase 2, open-label, single group, one-time, fixed-dose study is to assess the safety and efficacy of bilateral intraputaminal infusion of AB-1005 (AAV2-GDNF gene therapy) in Japanese patients with moderate Parkinson's Disease (PD).

Inclusion Criteria:

• Male and female adults 45-75 years of age inclusive, at the time of signing of informed consent

• Diagnosed with Parkinson's disease in the past 4-10 years (inclusive) and currently meeting all the following criteria:

  1. Presence of bradykinesia PLUS any of the following: rigidity, rest tremor, postural instability
  2. Presence of motor fluctuations as measured by the PD Motor Diary
  3. Stable anti-parkinsonian medication regimen for 4 weeks or more, prior to screening
  4. Responsiveness to levodopa therapy

Exclusion Criteria:

• Known history or current evidence of medical, genetic, or neurological conditions that may provide an alternative to idiopathic PD diagnosis
• Presence or history of significant vascular and/or cardiovascular disease
• Presence of clinically significant cognitive impairment
• Presence or history of psychosis or impulse control disorder
• History of malignancy other than treated cutaneous squamous or basal cell carcinomas
• Presence of clinically relevant conditions that could compromise surgical suitability and/or subject safety
• Contraindication to magnetic resonance imaging and/or use gadolinium-based contrast agents
• Prior history of brain surgery including, but no limited: DBS, pallidotomy focused ultrasound thalamotomy, or other experimental neurosurgical procedure
• Chronic immunosuppressive therapy

Currently, there is no established plan for the sharing of Individual Patient Data (IPD) from this study. The availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA 'Principles for responsible clinical trial data sharing.' This pertains to the scope, timepoint, and process of data access.

As such, Bayer commits to considering requests from qualified researchers for patient- / study-level clinical trial data, and documents from clinical trials involving medicines and indications approved in the US and EU. However, this commitment does not reflect an active IPD sharing plan. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014.

Researchers can use www.vivli.org to request access to IPD and documents from clinical studies to conduct research. Information on Bayer's criteria for listing studies is provided in the member section of the portal.