This study is about a new medicine called litifilimab for people with Systemic Lupus Erythematosus (SLE). SLE is a condition where the body's defense system attacks its own cells, causing pain and swelling. In this study, researchers want to see if litifilimab can help improve symptoms and if it is safe. People in the study will continue to take their usual medicines, such as antimalarials or steroids. Participants will get either litifilimab or a placebo (a fake treatment) through injections under the skin every 4 weeks. The study will last for 52 weeks, but the total time, including follow-ups, is up to 80 weeks.

Key Points:

• The study involves up to 22 visits over 80 weeks.
• Participants are randomly assigned to receive litifilimab or a placebo.
• Researchers will not know which treatment participants receive.

Participants must meet certain health criteria and should not have conditions like HIV or severe kidney disease. The goal is to find out if litifilimab can make SLE symptoms better and if it is safe for use.