Off-label use of fumarate therapy for granulomatous and inflammatory skin diseases other than psoriasis vulgaris: a retrospective study.

Background Fumarates are approved for the systemic treatment of moderate and severe psoriasis vulgaris in Germany. However, a number of studies and case reports indicate their efficacy in the treatment of further inflammatory skin disorders or granulomatous skin diseases. Objectives To examine the efficacy and safety of fumarates for the treatment of granulomatous and inflammatory skin diseases other than psoriasis vulgaris. Patients and methods The therapeutic efficacy and side-effects of fumarate therapy were analysed retrospectively in patients with granuloma annulare (GA, n = 4), cutaneous sarcoidosis (SA, n = 1), lichen planus (LP, n = 3), pityriasis rubra pilaris (PRP, n = 1) or chronic discoid lupus erythematosus (CDLE, n = 1). Results Six patients (GA: 3/4; LP: 2/3; PRP: 1/1) showed complete clearance and two patients (GA: 1/3; SA: 1/1) had a partial response, and the CDLE patient showed stable disease under a combination therapy with hydroxychloroquine. Side-effects associated with fumarate therapy were seen in seven of ten patients and resolved spontaneously upon dose reduction or discontinuation of the therapy. Conclusion According to this data, fumarates may represent a new approach in the treatment of granulomatous and inflammatory skin diseases other than psoriasis vulgaris. For the first time, the successful treatment of LP and CDLE with fumarates is reported. Side-effects are not limiting in most cases, but can hamper a dose escalation.