Manglende effekt i tidligere systemiske terapier defineres med utilstrækkelig respons (PASI < 50 eller PGA mindre end god), eller forværring af sygdommen hos patienter, der var i behandling og som fik en passende dosis af en tilstrækkelig lang varighed, således at respons kunne måles hos mindst 3 af de største systemiske terapier, der var tilgængelig.
Failure on prior systemic therapies is defined as insufficient response (PASI < 50 or PGA less than good), or worsening of disease in patients while on treatment, and who were adequately dosed for a sufficiently long duration to assess response with at least each of the 3 major systemic therapies as available.