Additional Study Information: The purpose of this study is to determine if Acthar gel is a safe and effective therapy for patients with membranous (Class V) lupus nephritis. Class V lupus nephritis is associated with the development of chronic kidney disease and end-stage renal (kidney) disease, and there is no clear therapy for treatment. Currently used therapies arent completely effective in causing a decrease in symptoms of Class V lupus nephritis. In this study the safety of two different doses of Acthar gel and its ability to decrease the symptoms of Class V lupus nephritis will be assessed with the goal of determining whether Acthar gel is an effective and safe treatment for Class V lupus nephritis.