Severe recalcitrant cutaneous manifestations in systemic lupus erythematosus successfully treated with fumaric acid esters

Summary Fumaric acid esters (FAEs) have proven efficacy in the treatment of psoriasis and have been in use for decades. More recently, as their mechanism of action and abundant immunomodulatory effects become clearer, the potential benefits of treating other inflammatory skin conditions using FAEs are increasingly being recognized. The use of FAEs as combination systemic therapy has not been well studied and data are lacking regarding the safety and efficacy of this type of therapy. In this case report, three patients with severe, extensive and recalcitrant cutaneous manifestations of systemic lupus erythematosus (SLE) (one case of disseminated discoid lesions and two with severe chilblain lesions) were treated with Fumaderm® (containing the FAE dimethylfumarate and monoethylhydrogen fumarate salts), after failing to respond to a multitude of other monotherapies and combination therapies. All patients showed a substantial clinical response when FAEs were added to their treatment, with concurrent improvements in quality‐of‐life instrument scores. The treatment was well tolerated in the context of systemic organ involvement and as combination therapy with other agents, such as hydroxychloroquine and mycophenolate mofetil. These cases of SLE illustrate the potential use of FAEs in severe, disfiguring and otherwise therapy‐resistant skin lesions, including, to our knowledge, the first two reported cases of FAE‐treated chilblain lupus erythematosus. What's already known about this topic? Fumaric acid esters (FAEs) exert a variety of immunomodulatory, anti‐inflammatory and antioxidant effects. FAEs are an effective treatment for moderate‐to‐severe psoriasis and have been reported to be effective in treating other inflammatory and granulomatous skin diseases. What does this study add? We report the efficacious and well‐tolerated use of FAEs in the treatment of severe, extensive and recalcitrant cutaneous manifestations of systemic lupus erythematosus (SLE), previously treated unsuccessfully with several monotherapies and combination therapies. These cases demonstrate the safe use of FAEs with concurrent immunomodulatory and immunosuppressive therapies in the context of treating SLE. We report the first cases of chilblain lupus erythematosus treated with FAEs. Linked Comment: Kuhn et al. Br J Dermatol 2017; 176:301–302.