Secukinumab Provides Significant and Sustained Inhibition of Joint Structural Damage in a Phase III Study of Active Psoriatic Arthritis

In this phase III, double-blind, placebo-controlled study, 606 patients with psoriatic arthritis were randomised to intravenous (IV) secukinumab 10 mg/kg (weeks 0, 2, 4) followed by subcutaneous secukinumab 150 mg (IV→150 mg) or 75 mg (IV→75 mg), or placebo. Patients were stratified by prior anti-TNF (tumour necrosis factor) exposure (71% anti-TNF-naïve). At week 16, placebo-treated patients who had ≥20% reduction in tender and swollen joint count (responders) remained on placebo until week 24; non-responders were re-randomised to secukinumab 150 or 75 mg. The van der Heijde modified total Sharp score (mTSS) was determined at baseline, week 16/24 and week 52.In the overall population, radiographic progression was inhibited through 52 weeks; efficacy was demonstrated for both erosion and joint space narrowing scores and in patients who switched from placebo to secukinumab at week 24. Subgroup analyses showed secukinumab reduced progression at week 24, regardless of prior anti-TNF use; mean change from baseline to week 24 in mTSS in the secukinumab pooled and placebo groups was 0.05 and 0.57, respectively for anti-TNF-naïve patients and 0.16 and 0.58, respectively in anti-TNF-IR patients. Anti-TNF-naïve patients showed negligible progression through week 52. Inhibition of structural damage was observed through week 52, irrespective of concomitant methotrexate use. A high proportion of patients showed no progression (≤0.5) with secukinumab from baseline to week 24 (IV→150 mg, 82.3%; IV→75 mg, 92.3%) and from week 24 to week 52 (IV→150 mg, 85.7%; IV→75 mg, 85.8%).Secukinumab inhibited radiographic progression in patients with active psoriatic arthritis through 52 weeks of therapy.