This study is testing a new medicine called JNJ-79635322 to see if it helps people with a type of blood cancer called Multiple Myeloma. Multiple Myeloma affects cells in your blood that help fight infections. Relapsed means the cancer returned after treatment, and refractory means it didn't improve with treatment.

To join, you must have tried at least three different treatments before, including a PI (proteasome inhibitor), an IMiD (immunomodulatory drug), and an anti-CD38 mAb (monoclonal antibody). You should also not have any other active cancers that might affect the study results.

• Participants need to stop other cancer treatments before joining.
• Major surgeries are not allowed two weeks before starting or during the study.
• The study is for people who are generally healthy enough to participate, with an ECOG PS (Eastern Cooperative Oncology Group Performance Status) of 0 to 2.