Phase I Study to Evaluate KP405 in Healthy and Parkinson's Disease Patients

This Phase I study tests a new drug called KP405 in two groups: healthy volunteers (to assess safety) and people with Parkinson's disease (to assess both safety and early signs of effectiveness). This is an early-stage study focused on understanding how the drug behaves in the body. **You may be eligible if...** - You are a healthy adult with no significant medical conditions (for the healthy volunteer group), OR - You have been clinically diagnosed with Parkinson's disease meeting UK Brain Bank criteria (for the Parkinson's group) - You are willing to undergo medical evaluations including ECG, blood tests, and cardiac monitoring **You may NOT be eligible if...** - You have significant health conditions that a doctor determines make participation unsafe - You are pregnant or breastfeeding - You are currently taking medications that could interact with the study drug - You have a history of serious cardiac arrhythmias Talk to your doctor to see if this trial is right for you.