Impact of Concomitant MTX on Efficacy, Safety and Adherence of Ustekinumab-treatment in Patients With Active PsA

Methotrexate (MTX) co-medication can improve the therapeutic effect of biological therapies (e.g. Tumor necrosis factor (TNF) -inhibitors) in rheumatoid arthritis (RA), but its role in Psoriatic Arthritis (PsA) remains unclear. No data from Randomized Clinical Trials (RCTs) are available to address the questions whether add-on of MTX to UST monotherapy, or a withdrawal of continuous MTX therapy in patients with newly initiated Ustekinumab (UST) treatment or simultaneously induction of MTX with UST in naive active PsA-patients will influence outcome measurements. So, the purpose of the study is to analyse the effects of blinded MTX-co-medication on outcome in patients treated with UST: Non-inferiority at week 24 of UST monotherapy compared to add-on to MTX in patients with active PsA and at least 12 weeks of MTX treatment prior to screening or who are actually not treated with MTX and do not have prior inadequate response to MTX-treatment for PsA will be demonstrated.