Prescriptive Infusion Algorithm (PIA)

Participants will receive a one-time infusion of AB-1005 directly into the putamen on each side of the brain. This is done during a surgical procedure under general anesthesia. The drug is delivered using a special technique called convection-enhanced delivery (CED), which helps spread the drug evenly in the target brain tissue. The delivery method will use either MRI or CT scans to guide and check the placement of the infusion needle (cannula, which is a thin tube). The study has three main stages, the initial group of 6 participants and the other 2 stages with two small groups (sub-stages) of 3 participants. Each group will receive the same treatment, and results will be reviewed before moving to the next group. All participants will receive AB-1005. The study is open-label, meaning both participants and doctors know what treatment is given. After the follow-up period, all participants will continue into a long-term follow-up (LTFU) study. In the LTFU study, participants' health will be monitored for up to 10 years after their surgery.