This clinical trial is focused on studying Parkinson’s Disease, a condition that affects movement and can cause symptoms like tremors, stiffness, and difficulty with balance and coordination. The trial is testing a new treatment called BIIB122, which is a tablet taken orally. The purpose of the study is to evaluate how effective and safe BIIB122 is compared to a placebo, which looks like the real medication but does not contain any active ingredients.

Participants in the study will be randomly assigned to receive either BIIB122 or the placebo. The study is designed to be “double-blind,” meaning neither the participants nor the researchers will know who is receiving the actual medication or the placebo. This helps ensure that the results are not influenced by expectations about the treatment. The study will take place over a period of time, during which participants will be monitored for any changes in their symptoms and any side effects they might experience.

The main goal is to see if BIIB122 can slow down the worsening of symptoms associated with Parkinson’s Disease. Researchers will use a specific scale called the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) to measure changes in symptoms. They will also track any adverse events or serious adverse events that occur during the study. The study aims to provide valuable information about the potential benefits and risks of BIIB122 for people living with Parkinson’s Disease.