Long-term outcome of anti-tumor necrosis factor alpha blockade in the treatment of juvenile spondyloarthritis.

ABSTRACT

OBJECTIVES: A significant proportion of patients with juvenile spondyloarthritis (JSpA) are refractory to treatment with established medications. The objective of this study was to assess long-term efficacy of treatment with anti-TNF agents in patients with JSpA. METHODS: An observational study of 16 patients with JSpA from 3 centres treated with infliximab (n=10) and etanercept (n=6) was performed, with a median follow-up period of 7.2 years. Prospective data was collected according to a standardized protocol. Outcomes examined were TEC, TAJC, markers of inflammation (ESR, CRP), functional assessments (C-HAQ, BASDAI, BASFI), and ongoing requirement for anti-TNF treatment. RESULTS: 13/16 patients (83%) had achieved clinical remission 6 months into the treatment. Improvement was sustained over time, with a median TAJC and TEC of 0 at any time point after 6 weeks. 6/16 patients (38%) showed a flare of arthritis after a median of 3.5 years. Two patients with hip disease prior to treatment required an arthroplasty 3 and 8 years post anti-TNF initiation. Patients showed progression of sacroiliitis with median modified New York score of 1 (range 0-3) at time of diagnosis and 3 (range 0-4) at last follow-up (p=0.002). Median BASDAI at last follow up was 1.6, median BASFI 3.1. Two patients developed transient reactions (one generalised, one local); no patient developed other adverse effects during the study. CONCLUSIONS: Anti-TNF treatment in JSpA refractory to standard treatment results in good long-term disease control except for pre-existing hip disease. However, radiographic evidence suggests inferior efficacy for control of sacroiliac joint disease.