Fumaric acid esters (FAEs), particularly dimethyl fumarate (DMF), have a well-established role in the treatment of moderate-to-severe plaque psoriasis. Their use is scientifically validated, with a history dating back to the 1950s in Germany. The most commonly used FAE formulation is a mixture including DMF, which is licensed for psoriasis treatment in several European countries. The therapeutic effect is believed to arise from immunomodulatory and anti-inflammatory actions, such as inhibition of pro-inflammatory cytokines and modulation of T cell activity.

Multiple randomized controlled trials (RCTs) and real-world studies have demonstrated the clinical efficacy of FAEs in reducing Psoriasis Area and Severity Index (PASI) scores compared to placebo. A systematic review and meta-analysis published in the Journal of the American Academy of Dermatology (2017) confirmed their efficacy and safety profile. Common side effects include gastrointestinal symptoms and flushing, but serious adverse events are rare with appropriate monitoring.

Due to the robust clinical data and longstanding use in clinical practice, FAEs are recommended in several national and international psoriasis treatment guidelines. However, they are less commonly used outside Europe, in part because other systemic therapies (e.g., methotrexate, biologics) are preferred in some regions.