Psoriasis is a chronic immune-mediated disease with significant clinical and immunological heterogeneity. Although methotrexate and cyclosporine are widely used in moderate to severe psoriasis, their comparative effects on IL-33 - a key pro-inflammatory cytokine - have not been adequately evaluated. In this randomized controlled trial involving 118 Egyptian psoriatic patients, we directly compared the therapeutic efficacy of methotrexate versus cyclosporine and analyzed their impact on serum IL-33 levels in relation to Psoriasis Area and Severity Index (PASI).
Our findings demonstrated that while both drugs significantly reduced PASI scores and IL-33 serum levels, cyclosporine showed superior efficacy and achieved a greater reduction in both clinical severity and IL-33. A strong positive correlation was observed between IL-33 levels and PASI scores, supporting IL-33 as a reliable biomarker of disease activity and therapeutic response.
This is one of the few clinical studies in Egypt and the region evaluating IL-33 modulation in psoriasis therapy. Our results may guide clinicians in selecting optimal systemic treatment and highlight IL-33 as a potential therapeutic target.