**Study Summary** This study focuses on people with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL), which are blood cancers. These diseases can cause symptoms like enlarged lymph nodes, night sweats, weight loss, and fever. The study compares a new treatment, BGB-16673, to other existing options chosen by doctors. Treatments include idelalisib plus rituximab, bendamustine plus rituximab, or venetoclax plus rituximab. The goal is to see if BGB-16673 helps patients live longer without their disease worsening. **Key Points:** - About 250 participants worldwide will join, and treatment is assigned randomly. - Participants must have had previous treatments with both BTK and BCL2 inhibitors. - The study involves regular check-ups, and participants should be in good health overall. To join, participants need a confirmed diagnosis of CLL/SLL and meet health criteria. However, those with other specific health issues or treatments cannot participate. The study is sponsored by BeOne Medicines, previously known as BeiGene.

Remember to discuss with your doctor if you’re interested in participating.