Patient characteristics associated with use of TNF vs interleukin inhibitors as first-line biologic treatment for psoriatic arthritis

Abstract

BACKGROUND: Previous studies have examined treatment patterns among patients who use tumor necrosis factor (TNF) inhibitors for psoriatic arthritis (PsA). However, little data exist for a comparison between the TNF inhibitor treatment pattern and that of newly available biologics such as interleukin (IL)-12/23 or 17 inhibitors in the United States. OBJECTIVES: To (a) examine patient characteristics and their association with initiation of TNF inhibitors vs IL-12/23 or 17 inhibitors among PsA patients and (2) compare treatment persistence of PsA patients who initiated TNF inhibitors vs IL-12/23 or 17 inhibitors as first-line biologic treatment in a real-world setting in the United States. METHODS: Using claims data from MarketScan (2013-2017), we identified a cohort of PsA patients who initiated TNF inhibitors or IL-12/23 or 17 inhibitors. The primary outcome was treatment persistence, defined as continuous use of the index drug at 1 year, regardless of refill gaps. The secondary outcome was treatment persistence with high adherence at 1 year (ie, refill gaps ≤30 days). Multivariable logistic regression was used to assess the association between patient characteristics and treatment initiation and persistent use of TNF inhibitors vs IL-12/23 or 17 inhibitors. RESULTS: We identified 3,180 TNF inhibitor initiators and 214 IL-12/23 or 17 inhibitor initiators. Initiators of IL-12/23 or 17 inhibitors had more comorbidities than TNF inhibitor initiators. The proportion of patients with treatment persistence was 53.0% in TNF inhibitor initiators and 53.7% in IL-12/23 or 17 inhibitor initiators; 37.1% of TNF inhibitor users and 24.8% of IL-12/23 or 17 inhibitor users were treatment persistent with high adherence. There was no difference in 1-year treatment persistence between the 2 groups after adjusting for baseline characteristics (adjusted odds ratio [aOR] for TNF inhibitors vs IL-12/23 or 17 inhibitors: 0.86, 95% CI=0.63-1.15). However, use of TNF inhibitors was associated with a greater treatment persistence with high adherence compared with use of IL-12/23 or 17 inhibitors (aOR=1.61, 95% CI=1.15-2.26). CONCLUSIONS: PsA patients who initiated an IL 12/23 or 17 inhibitor had a greater comorbidity burden compared with those who initiated TNF inhibitors. Treatment persistence was similar between the 2 groups, whereas medication adherence was higher with TNF inhibitors than with IL 12/23 or 17 inhibitors during the first year of treatment.