Roflumilast is a phosphodiesterase-4 (PDE-4) inhibitor, which is approved in its oral form
for chronic obstructive pulmonary disease, and in its topical form in the treatment of plaque
psoriasis. Methotrexate is one of the conventional systemic treatments of psoriasis, so the
aim of this study is to compare the efficacy and safety of roflumilast and methotrexate in
the treatment of psoriasis