This study is testing the safety and effectiveness of a drug called MK-6194 for adults with a disease called Systemic Lupus Erythematosus (SLE). SLE is an illness where the immune system attacks the body's own tissues. The study will compare MK-6194 to a placebo (a pill with no medicine) to see if it helps more people respond positively by Week 28.

To join, you must have had SLE for at least 6 months and be on certain medications for it. You need to have specific symptoms like a rash or swollen joints and certain blood test results. You cannot join if you have serious health problems like heart failure, some lung diseases, or certain infections. Also, you can't be in the study if you've had recent major surgery or if you're on too many other medications.

• The study lasts 28 weeks with several visits to the clinic.
• Participants will receive either MK-6194 or a placebo.
• There are risks like no improvement or potential side effects.