Long-term Follow-up of Glutamic Acid Decarboxylase (GAD) Gene Transfer in Parkinson's Disease

Long-term Follow-up of Glutamic Acid Decarboxylase Gene Transfer to the Subthalamic Nuclei in Participants With Parkinson's Disease

The objective of this study is to evaluate the long-term safety of AAV-GAD delivered bilaterally to the subthalamic nuclei (STN) in participants with Parkinson's disease.

The duration of individual participation in this study will be approximately 54 months for participants who received AAV-GAD in Study MGT-GAD-025 and approximately 60 months for participants who received sham surgery in Study MGT-GAD-025.

Inclusion Criteria:

• Previously enrolled in Study MGT-GAD-025.

Exclusion Criteria:

• None