Stober C, et al. - An exploratory analysis was pursued of the tumour necrosis factor alpha (TNF-α) inhibitor (TNFi) persistence when used as first- or second-line biologic therapy for the management of psoriatic arthritis (PsA). It also sought to identify the baseline clinical and laboratory parameters related to TNFi persistence. A lower TNFi persistence was reported among patients with PsA, who were female and presented with metabolic syndrome-related co-morbidities. Despite the lower persistence in patients who had switched to a second TNFi, a significant ratio of these cases responded. This, in turn, advocated the shift to a second TNFi, as a valid therapeutic strategy.

Methods

• The scheme of this research was a retrospective single-centre cohort study.
• It included all patients with PsA initiated on TNFi therapy between 2003 and 2015.
• A comparison was performed of the demographic, clinical and laboratory characteristics with TNFi persistence, via Kaplan-Meier survival and Cox proportional hazards models.

Results

• TNFi therapy was prescribed for 188 patients with PsA, as a first-line biologic therapy over a period of 635 person-years [46% male, mean (S.D.) age 47.3 (11.4) years; median (interquartile range) disease duration 11 (7-16) years].
• At 12 months of follow-up 79% of patients persisted with TNFi therapy, and 73% at 24 months.
• Amongst those discontinuing TNFi, 35% stopped as a result of primary inefficacy, 22% secondary inefficacy and 43% adverse events.
• Female sex (hazard ratio (HR) 2.57; 95% CI: 1.26, 5.24; P=0.01) and the presence of metabolic syndrome-related co-morbidities (HR=2.65, 95% CI: 1.24, 5.69; P=0.01) were identified as predictors of lower persistence.
• Persistence at 12 months appeared to be 56%, among the 32 cases treated with a second TNFi.
• TNFi persistence displayed 2-fold lesser likelihood in these 32 cases compared with first-line TNFi users (HR=2.02, 95% CI: 1.20, 3.42; P=0.01).