Dynamics of concomitant therapy in children with juvenile idiopathic arthritis treated with etanercept and methotrexate

Background: Both the steroid- and NSAID-sparing effects of biologics in juvenile idiopathic arthritis (JIA) treatment are key aspects of the dynamics of patient's condition. The proper selection of biologics enables maximum treatment effectiveness and reduction of the dosage of concomitant therapy. Our aim was to study the dynamics of concomitant therapy during etanercept (ETA) and methotrexate (MTX) treatment in patients with JIA.

Methods: This analysis included 215 JIA patients (63.3% females) showing sufficient response to main therapy. One hundred patients received MTX as main therapy, 24 received ETA monotherapy, and 91 received ETA þ MTX combination therapy. The dynamics of concomitant therapy were analyzed after 1 month, every 3 months during the first year, and every 6 months during the long-term follow-up (up to 5 years).

Results: At the baseline, 24 (11.2%) patients received concomitant oral glucocorticoids (orGCs) and NSAIDs; the remaining 191 (88.8%) patients were treated with concomitant NSAIDs only. Within 1-year treatment, NSAIDs were discontinued in 162 (75.3%) patients. There were no significant differences in the dynamics of withdrawal of NSAIDs in patients who received and did not receive concomitant MTX. However, the percentage of treatment discontinuation in the MTX group was significantly lower compared to the other two groups (p < 0.001). Oral GCs were discontinued completely in 4 children (16.7%), and the dose of oral GCs was reduced in another 4 patients (16.7%). By the end of the follow-up period, 44 of 115 patients (38.3%) treated with ETA in combination with any concomitant therapy could switch to ETA monotherapy.

Conclusion: Therapy with ETA makes it possible to reduce the dosage or completely discontinue most concomitant medications (orGCs, NSAIDs, MTX) in a significant percentage of patients. This reduces the risk of development of NSAID- and GC-induced pathological conditions, while the effectiveness of therapy of the underlying condition remains high.