If you join this study, you will first go through screening to make sure the study is a good fit for you. After that, you will receive treatment and be followed over time. People are placed into treatment groups by chance and will get either a study medicine or a usual cancer treatment. The study has two parts. One part is for people whose cancer does not respond to platinum medicine, and the other part is for people whose cancer still responds to platinum medicine. Treatments are given through a vein, usually once every three weeks. During the study, you will go to regular clinic visits for checkups, blood tests, scans, and safety checks. Treatment will continue as long as it helps and the side effects stay manageable.