Efficacy and safety of TNFα antagonist therapy in patients with juvenile spondyloarthropathies

Abstract

Objectives To evaluate the efficacy and safety of TNFα antagonist therapy in patients with juvenile spondyloarthropathies refractory to nonsteroidal anti-inflammatory drugs (NSAIDs). Methods Retrospective review of the medical charts of 20 patients (16 males and 4 females) with a mean age of 11.6 years at diagnosis. Median time from diagnosis to initiation of TNFα antagonist therapy was 41 months. Escape phenomenon developed in 3 patients, who were switched to another TNFα antagonist. Etanercept was used for 19/23 treatments, infliximab for 3/23 treatments, and adalimumab for 1 treatment. The efficacy criteria were morning stiffness duration; nocturnal awakenings; tender and swollen joint counts; entheseal count; back, buttock, and hip pain; percentage of patients on NSAIDs and/or glucocorticoid therapy; and mean and median values of the erythrocyte sedimentation rate, C-reactive protein level, and hemoglobin level. A remission was defined as resolution of the axial and peripheral pain, joint swelling, and laboratory evidence of inflammation, with or without continued NSAID therapy. Results TNFα antagonist therapy was associated with clinical and laboratory improvements after 3 months, and the benefits were sustained after 1 year. Axial pain required 6 months to improve. A remission was achieved in 59% of patients after 3 months and 70% after 6 and 12 months. Median time to remission under treatment was 3 months. The interval between the TNFα antagonist injections was increased for 12/18 treatments and the treatment was stopped in 7 cases. However, treatment discontinuation was consistently followed by a relapse, after a median time of 2.5 months. Two serious adverse events occurred, namely, acute bacterial pneumonia and recurrent impetigo; in both cases the outcome was promptly favorable after a brief interruption of the TNFα antagonist. Conclusion TNFα antagonist therapy seems safe and rapidly effective in patients with juvenile spondyloarthropathies refractory to NSAIDs, in keeping with data from adults. However, prospective studies in larger patient populations are needed.