**Study Purpose:** This study aims to test if a new drug called BHV-8000 works well, is safe, and is easy to handle for people with early Parkinson's disease (PD). Parkinson's disease is a brain disorder that causes shaking, stiffness, and difficulty with walking and balance. **Study Design:** Participants will be part of a 96-week study. The first half (48 weeks) is "double-blind," meaning neither the participants nor the researchers know who gets the real drug or a placebo (a fake treatment). The second half (another 48 weeks) is "open-label," where everyone gets BHV-8000, and both participants and researchers know this. **Key Points:** - **Duration:** The study lasts for 96 weeks in total. - **Visits Needed:** Participants will need to attend multiple visits to check how they are doing. - **Eligibility:** Only adults aged 40 to 80 with early PD can join. You cannot join if you have other serious brain disorders or are a smoker. This study helps ensure that BHV-8000 is a good option for treating early PD symptoms. If you're interested, consider the time commitment and eligibility requirements.