**K0706 for Patients Diagnosed With Dementia With Lewy Bodies** This study is looking at a new medicine, K0706, to see if it is safe and if it works for people with Dementia with Lewy Bodies (DLB). DLB is a condition where people have problems with memory and movement, like Parkinson's and Alzheimer's. We want 45 people to join, and they will be split into 3 groups. Each group will take either a low dose or high dose of K0706, or a fake medicine called a placebo, for 12 weeks. After that, there will be a 4-week break. - **Length**: The study lasts for 16 weeks in total. - **Visits**: Participants need to agree to some tests, like a lumbar puncture, at the start and after 3 months. - **Risks**: The study will check for any side effects or risks from taking K0706. To join, participants need to be between 25-90 years old and have a diagnosis of DLB. They should not have other serious health problems or be pregnant. If interested, participants must sign a consent form.