Supplementary Material for: The Implications of Recent Recommendations for Managing Patients with Psoriasis Treated with Fumaric Acid Esters

<i>Background/Aims:</i> Fumaric acid esters (FAEs) are a well-established efficacious systemic treatment for psoriasis. Recent recommendations from the European Medicines Agency suggest monitoring of full blood count every 4 weeks for the duration of therapy for psoriasis. The aim of our study was to assess the incidence of lymphopenia in patients taking FAEs and the impact of recent recommendations for our practice. <i>Methods:</i> We reviewed 151 patients treated with FAEs for psoriasis between December 2013 and 2015. <i>Results:</i> Lymphopenia <700 × 109/L was detected within the last 12 months in 36/151 (24%) and lymphopenia <500 × 109/L in 10/151 (7%). Of 39 patients no longer on treatment, 7 (18%) stopped because of persistent lymphopenia. <i>Conclusion:</i> The implementation of these recommendations would have significant resource implications and also likely influence the acceptability of FAEs to patients. Cessation of FAEs necessitates the need for alternative therapy, commonly biologic therapy.