This study is for patients with untreated Chronic Lymphocytic Leukemia (CLL) or Small Lymphocytic Lymphoma (SLL). The trial uses a combination of medicines to see how well they work together. **Venetoclax** blocks a protein that helps cancer cells survive. **Obinutuzumab** is a special protein that stops cancer cells from growing. **Epcoritamab** helps the immune system kill cancer cells. Patients take these medicines over several cycles lasting 28 days each.

Key Points:

• Study involves 12 treatment cycles, with follow-up visits up to 5 years.
• Blood tests, CT or MRI scans, and possibly bone marrow tests are required.
• Participants must be adults and meet certain health criteria.

This study aims to see if adding epcoritamab makes the treatment more effective. There are safety checks to ensure participants' well-being. Patients should consider the time commitment and their ability to attend regular medical visits when deciding to participate.