This study is about finding out how well a drug called iberdomide works alone or with another drug, dexamethasone, for people with a condition called smoldering multiple myeloma (SMM). SMM is when abnormal cells are in the bone marrow but not causing serious problems yet. Iberdomide is a type of medicine that helps the immune system fight cancer, while dexamethasone is a synthetic steroid that helps stop cancer cells from growing.

In this study, one group will receive both drugs, while another group will only receive iberdomide. The study checks how well these treatments work and if they have any side effects. Patients are monitored during treatment and followed up for 4 weeks, then every 6 months.

• Study involves taking pills daily and might last multiple months.
• Participants are checked regularly to see how their condition is responding.
• Women must take pregnancy tests and everyone must agree to use birth control.