The purpose of the study is to evaluate the safety and tolerability of BBM-P002 for stereotactic injection to treat participants with idiopathic Parkinson's Disease (PD) during the dose-limiting toxicity (DLT) observation period.

This is a single-arm, open-label study to evaluate the safety, tolerability, efficacy, pharmacokinetic, pharmacodynamic, and immune response of BBM-P002 within 52 weeks after into the bilateral putamen in Parkinson's disease, as well as the long-term safety and efficacy of BBM-P002 for up to 5 years post injection.

BBM-P002 is an AAV-based gene therapy that delivers a therapeutic gene cassette into putamen for the treatment of Parkinson's Disease.

Inclusion Criteria:

1. Participants with a diagnosis of Parkinson's disease for ≥ 5 years.
2. The Hoehn-Yahr staging meets the requirements during the OFF periods.
3. The MDS-UPDRS Part III score met the requirements during the OFF periods. the levodopa challenge test was positive
4. During the screening period, participants were required to take the same stable dose of dopamine-releasing drugs (such as levodopa) regularly
5. The participants agreed to postpone the neurosurgical procedures related to the indication treatment during the main study phase
6. The participants agreed not to participate in any other therapeutic intervention studies during the trial period
7. The participants agreed not to receive the vaccine during the main study phase
8. From the screening period until at least 52 weeks after dosing, use a reliable contraceptive method
9. The participants had good compliance and were able to undergo regular follow-ups. During the follow-up period, they were able to accurately complete the diary cards. Family members, guardians or caregivers could assist the subjects in filling out the diary cards
10. Voluntarilyvoluntarily participated in the study and signed the informed consent form

Exclusion Criteria:

1. Atypical or secondary Parkinsonism
2. Have contraindications for surgery or have previously undergone brain surgery
3. The participants has an abnormal brain MRI suggestive of brain pathology other than Parkinson's disease
4. Those with severe cognitive impairments
5. Those with severe depression or severe anxiety
6. Abnormal liver function
7. Abnormal coagulation function
8. Abnormalities in infectious disease screening
9. Currently undergoing antiviral treatment for hepatitis
10. Suffering from unstable or severe diseases in the cardiovascular, respiratory, digestive, nervous, hematological, immune and other systems
11. Suffering from malignant tumors or having a history of tumors
12. Previous history of severe allergies
13. Exclude those who have participated in other clinical trials within the past three months
14. Had received gene therapy during the screening period
15. Select those who have received stem cell treatment within the past 12 months
16. Exclude those who have used other investigational drugs within the past 4 weeks
17. During the screening period, if the individual had received live vaccines within the previous 2 months, or had a history of vaccination within the last 30 days, they would be excluded.
18. Having a history of alcohol dependence or drug addiction
19. Pregnant or lactating female participants
20. The situations that were determined by the investigator to be unsuitable for inclusion in the study