Comparative effectiveness and persistence of TNFi and non-TNFi in juvenile idiopathic arthritis: a large paediatric rheumatology centre in the USA.

ABSTRACT

OBJECTIVE: To evaluate the persistence and effectiveness of TNF inhibitors (TNFi) vs non-TNFi among newly diagnosed JIA patients after initiation of biologic DMARD (bDMARD). METHODS: Using longitudinal patient-level data extracted from electronic medical records in a large Midwestern paediatric hospital from 2009 to 2018, we identified JIA patients initiating TNFi and non-TNFi treatment. Treatment effectiveness was assessed based on disease activity. Inverse probability of treatment weighting of propensity score was used to estimate the treatment effectiveness and Kaplan-Meier analyses were conducted to assess persistence. RESULTS: Of 667 JIA patients, most (92.0%) were prescribed one of the class of TNFi as their initial biologic treatment. Etanercept was the most frequently prescribed (67.1%) treatment, followed by adalimumab (27.5%). Only around 5% of patients were prescribed off-label bDMARDs as their first-course treatment; however, >20% were prescribed off-label biologics as their second-course therapy. Some 7.2% of patients received four or more bDMARDs. The median persistence of the first-course bDMARD is 320 days, with TNFi being significantly longer than the non-TNFi (395 vs 320 days, P = 0.010). The clinical Juvenile Disease Activity Score (cJADAS) reduction of TNFi users (6.6, 95% CI 5.7, 7.5) was significant greater compared with non-TNFi users (3.0, 95% CI 1.5, 4.6, P < 0.0001) at 6-month follow-up visit. CONCLUSION: Persistence was significantly longer among patients initiating TNFi as their first biologic therapy than those receiving non-TNFi. Patients receiving TNF therapy had significant greater reduction of cJADAS at the 6-month follow-up visit compared with patients in the non-TNF cohort.