The planned length of participation in the study for each participant will be approximately 7 months. This includes a screening period of up to 40 days, randomization and surgery, and a follow-up period of 26 weeks.
The objective of this clinical trial is to evaluate the safety and tolerability of adeno-associated virus (AAV)-mediated delivery of glutamic acid decarboxylase (GAD) gene transfer into the subthalamic nuclei (STN) of participants with Parkinson's Disease.