This study is testing a medicine called **felzartamab** for people with **Lupus Nephritis (LN)**, a kidney problem caused by **Systemic Lupus Erythematosus (SLE)**, which is an immune system disease. The trial checks if felzartamab is safe and works well when used with regular care. To join, you need a lupus diagnosis based on specific guidelines and a recent kidney test showing certain conditions. You should have tried other treatments for at least three months without success. You can't join if you have very fast kidney damage, too much kidney scarring, need kidney machines (dialysis), or have had a kidney transplant.

• **Duration:** The study lasts until the treatment and evaluations are completed.
• **Participation:** You’ll need visits for testing and treatment.
• **Risks:** There may be side effects, and it's important to discuss these with your doctor.

If you have questions or want to join, talk to your doctor. They can help see if this study is a good fit for you.