Patients with psoriasis resistant to multiple biological therapies: characteristics and definition of a difficult‐to‐treat population. (24th May 2022) - Mastorino, Luca; Roccuzzo, Gabriele; Dapavo, Paolo; Siliquini, Niccolò; Avallone, Gianluca; Rubatto, Marco; Merli, Martina; Agostini, Andrea; Ribero, Simone; Quaglino, Pietro