Apremilast in Persistent Mucocutaneous Erythema Multiforme: A Case Report - Expanding the Therapeutic Evidence

Persistent erythema multiforme (EM) is a rare and poorly defined variant of EM characterized by prolonged mucocutaneous involv ent and limited therapeutic options. Evidence regarding its management is scarce. Apremilast has shown efficacy in isolated reports of other EM subtypes, suggesting a potential role in refractory cases.

We present the case of a 45-year-old woman with recurrent EM who subsequently developed prolonged, continuously active mucocutaneous disease lasting 6 years. The disease was refractory or intolerant to multiple therapies, including antivirals, corticosteroids, colchicine, dapsone, hydroxychloroquine, azathioprine, and biologic agents. Extensive clinical, histopathological, immunological, and systemic evaluation supported the diagnosis of EM and did not identify an underlying condition. Apremilast (30 mg twice daily) was initiated resulting in progressive improvement, with complete resolution of oral involvement within 3 months. After 1 year of follow-up, the patient remains in sustained clinical remission with good tolerability and no significant adverse effects.

This case adds to the limited evidence supporting the potential use of apremilast in difficult-to-treat EM with prolonged mucocutaneous activity. Although the rapid and sustained response observed in this patient is encouraging, further studies are needed to determine the efficacy, optimal treatment duration, and long-term safety of apremilast in this setting.