This clinical trial is focused on studying a condition known as Relapsed/Refractory Multiple Myeloma, which is a type of blood cancer that affects plasma cells in the bone marrow. The study is investigating the effects of a treatment called Cevostamab, which is given as a solution through an infusion into the vein. The purpose of the study is to evaluate how effective and safe Cevostamab is for patients who have previously been treated with therapies targeting a specific protein called B Cell Maturation Antigen (BCMA) and have experienced a return or worsening of their disease.

During the study, participants will receive Cevostamab and will be monitored for their response to the treatment and any side effects they may experience. The study will also involve the use of another medication called Tocilizumab, which may be administered to manage certain side effects related to the immune system. The trial will take place over several years, with regular assessments to track the progress of the disease and the overall health of the participants.

The study aims to gather information on how well Cevostamab works in controlling the disease and improving the quality of life for patients. It will also look at how long the treatment effects last and how it impacts survival rates. By participating in this study, researchers hope to find better ways to treat Relapsed/Refractory Multiple Myeloma and improve outcomes for patients facing this challenging condition.