The protocol of a clinical effectiveness trial comparing standard step-up care, early combination DMARD therapy and early use of TNF inhibitors for the treatment of moderate to severe psoriatic arthritis: the 3-arm parallel group SPEED randomized controlled trial.

Objectives: The aim of the Severe Psoriatic arthritis - Early intervEntion to control Disease trial is to compare outcomes in psoriatic arthritis (PsA) patients with poor prognostic factors treated with standard step-up conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), combination csDMARDs or a course of early biologics. Design: This multicentre UK trial was embedded within the MONITOR-PsA cohort, which uses a trial within cohort design. Methods and analysis: Patients with newly diagnosed PsA and at least one poor prognostic factor (polyarthritis, C-reactive protein >5 mg/dL, health assessment questionnaire >1, radiographic erosions) were randomized equally and open-label to either standard care with 'step-up' csDMARD therapy, initial therapy with combination csDMARDs (methotrexate with either sulfasalazine or leflunomide) or to early biologics induction therapy (adalimumab plus methotrexate). The primary outcome is the PsA disease activity score at week 24. Ethics: Ethical approval for the study was granted by the South Central Research Ethics Committee (ref 18/SC/0107). Discussion: Treatment recommendations for PsA suggest more intensive therapy for those with poor prognostic factors but there are no studies that have previously used prognostic factors to guide therapy. Applying initial intensive therapy has shown improved outcomes in other inflammatory arthritides but has never been tried in PsA. Combination csDMARDs have shown some superiority over single therapies but there are limited data and concerns about side effects. Early use of biologics has also been shown to be superior to methotrexate but these drugs are costly and not usually funded first line. However, if a short course of biologics can rapidly suppress inflammation allowing treatment to be withdrawn and response maintained on methotrexate, this may be a cost-effective model for early use. Trial registration: ClinicalTrials.gov (NCT03739853) and EudraCT (2017-004542-24).