Multiple Myeloma is a type of cancer that affects the blood. This study is testing two different drug combinations to see which works better for patients whose cancer has returned after treatment. One combination is called MeziVd, which includes mezigdomide, bortezomib, and dexamethasone. The other is PVd, which includes pomalidomide, bortezomib, and dexamethasone.

For this study, you need to have tried 1 to 3 other treatments for multiple myeloma before and received lenalidomide. You should also have a certain level of a protein called M-protein in your blood or urine, which helps confirm the diagnosis.

• **Study Length:** Participation involves multiple visits over a period of time.
• **Eligibility:** Check if you have had the right number of treatments before and can meet other health criteria.
• **Safety:** The study compares the safety of the drug combinations, but there might be risks, so discuss with your doctor.

If you're interested in participating, make sure you meet the criteria and discuss the potential risks and benefits with your healthcare provider. Always consult your doctor before joining any clinical study.