Pegylated Liposomal Doxorubicin Plus Adebrelimab With or Without Mirabegron in Relapsed Ovarian Cancer

The goal of this clinical trial is to learn if drug regimen pegylated liposomal doxorubicin and adebrelimab with or without mirabegron works to treat relapsed ovarian cancer in adults. It will also learn about the safety of drug regimen pegylated liposomal doxorubicin and adebrelimab with or without mirabegron. The main questions it aims to answer are: Does drug pegylated liposomal doxorubicin and adebrelimab with or without mirabegron reduce tumor volume? What medical problems do participants have when taking drug pegylated liposomal doxorubicin and adebrelimab with or without mirabegron? Researchers will compare drug regimen pegylated liposomal doxorubicin and adebrelimab with mirabegron to a drug regimen pegylated liposomal doxorubicin and adebrelimab without mirabegron to see which drug regimen works better to treat relapsed ovarian cancer. Participants will: Take drug pegylated liposomal doxorubicin and adebrelimab every 21 days with or without everyday mirabegron Visit the clinic once every 2 months for checkups and tests Keep a diary of their symptoms